Chapter 9              THE FIELD DEVELOPMENT PROCESS    This chapter covers some of the important technical aspects of the...
2                                                 Murray Hunter‘green revolution’ of the 1960s improved genetic materials,...
Enterprise Viability and New Crop Potential                                                                3              ...
4                                        Murray Hunter              Table 9.1. Major Eco-Systems, Production Systems and O...
Enterprise Viability and New Crop Potential                          5failed to sign the Kyoto Protocol, claiming the econ...
6                                       Murray Hunter          denigrating the environment for others. Some pests will bec...
Enterprise Viability and New Crop Potential                         7Thus efforts to uplift yield and quality may have lit...
8                                          Murray Hunterso temperature is a major factor in adaptability. Plant adaptation...
9                                                                                                                         ...
10                                      Murray Hunter     •   The C3 plants incorporate CO2 into 3-carbon compounds. The s...
Enterprise Viability and New Crop Potential                           11    However the above analysis can be misleading a...
12                                    Murray Hunteressential oil and a mapping of the metabolic pathways that produce the ...
Enterprise Viability and New Crop Potential                             13  Carbon dioxide                Glycolysis    Gl...
14                                          Murray Hunter     IPP          DMPP                   Isomerization     Gerany...
Enterprise Viability and New Crop Potential                           15          SELECTION AND ACQUISITION OF GENETIC MAT...
16                                    Murray Hunter     Table 9.6. A Summary List of Australian Species with Chemotype Var...
Enterprise Viability and New Crop Potential                       17                             No. 3             Germacr...
18                                       Murray Hunterindicate that abrupt changes in climate can be correlated with chemi...
Enterprise Viability and New Crop Potential                          19         c) Distillation time taken, the part of pl...
20                                      Murray Huntergroup of trees, before seeds fully mature. However there are numerous...
Enterprise Viability and New Crop Potential                                   21                                          ...
22                                     Murray Huntersafety, environment protection, water management, building and fire re...
Enterprise Viability and New Crop Potential                          23        g) Degradation (salinity, acidity, erosion)...
24                                       Murray Hunterfrom the point of view of gaining local cooperation and goodwill ver...
Enterprise Viability and New Crop Potential                           25    a.   The suitability of land slopes, effective...
26                                         Murray Hunterclimate and topography assessment provide an understanding of what...
Enterprise Viability and New Crop Potential                       27Altitude     The existence of mountainous regions in P...
28                                       Murray HunterAlthough other mountainous regions will have their own specific spec...
Enterprise Viability and New Crop Potential                              29          Rainfall (Moisture Source)           ...
Essential oils: Art, Science, Agriculture, Industry & Entrepreneurship: A focus on the Asia-Pacific Region Sample Chapter ...
Essential oils: Art, Science, Agriculture, Industry & Entrepreneurship: A focus on the Asia-Pacific Region Sample Chapter ...
Essential oils: Art, Science, Agriculture, Industry & Entrepreneurship: A focus on the Asia-Pacific Region Sample Chapter ...
Essential oils: Art, Science, Agriculture, Industry & Entrepreneurship: A focus on the Asia-Pacific Region Sample Chapter ...
Essential oils: Art, Science, Agriculture, Industry & Entrepreneurship: A focus on the Asia-Pacific Region Sample Chapter ...
Essential oils: Art, Science, Agriculture, Industry & Entrepreneurship: A focus on the Asia-Pacific Region Sample Chapter ...
Essential oils: Art, Science, Agriculture, Industry & Entrepreneurship: A focus on the Asia-Pacific Region Sample Chapter ...
Essential oils: Art, Science, Agriculture, Industry & Entrepreneurship: A focus on the Asia-Pacific Region Sample Chapter ...
Essential oils: Art, Science, Agriculture, Industry & Entrepreneurship: A focus on the Asia-Pacific Region Sample Chapter ...
Essential oils: Art, Science, Agriculture, Industry & Entrepreneurship: A focus on the Asia-Pacific Region Sample Chapter ...
Essential oils: Art, Science, Agriculture, Industry & Entrepreneurship: A focus on the Asia-Pacific Region Sample Chapter ...
Essential oils: Art, Science, Agriculture, Industry & Entrepreneurship: A focus on the Asia-Pacific Region Sample Chapter ...
Essential oils: Art, Science, Agriculture, Industry & Entrepreneurship: A focus on the Asia-Pacific Region Sample Chapter ...
Essential oils: Art, Science, Agriculture, Industry & Entrepreneurship: A focus on the Asia-Pacific Region Sample Chapter ...
Essential oils: Art, Science, Agriculture, Industry & Entrepreneurship: A focus on the Asia-Pacific Region Sample Chapter ...
Essential oils: Art, Science, Agriculture, Industry & Entrepreneurship: A focus on the Asia-Pacific Region Sample Chapter ...
Essential oils: Art, Science, Agriculture, Industry & Entrepreneurship: A focus on the Asia-Pacific Region Sample Chapter ...
Essential oils: Art, Science, Agriculture, Industry & Entrepreneurship: A focus on the Asia-Pacific Region Sample Chapter ...
Essential oils: Art, Science, Agriculture, Industry & Entrepreneurship: A focus on the Asia-Pacific Region Sample Chapter ...
Essential oils: Art, Science, Agriculture, Industry & Entrepreneurship: A focus on the Asia-Pacific Region Sample Chapter ...
Essential oils: Art, Science, Agriculture, Industry & Entrepreneurship: A focus on the Asia-Pacific Region Sample Chapter ...
Essential oils: Art, Science, Agriculture, Industry & Entrepreneurship: A focus on the Asia-Pacific Region Sample Chapter ...
Essential oils: Art, Science, Agriculture, Industry & Entrepreneurship: A focus on the Asia-Pacific Region Sample Chapter ...
Essential oils: Art, Science, Agriculture, Industry & Entrepreneurship: A focus on the Asia-Pacific Region Sample Chapter ...
Essential oils: Art, Science, Agriculture, Industry & Entrepreneurship: A focus on the Asia-Pacific Region Sample Chapter ...
Essential oils: Art, Science, Agriculture, Industry & Entrepreneurship: A focus on the Asia-Pacific Region Sample Chapter ...
Essential oils: Art, Science, Agriculture, Industry & Entrepreneurship: A focus on the Asia-Pacific Region Sample Chapter ...
Essential oils: Art, Science, Agriculture, Industry & Entrepreneurship: A focus on the Asia-Pacific Region Sample Chapter ...
Essential oils: Art, Science, Agriculture, Industry & Entrepreneurship: A focus on the Asia-Pacific Region Sample Chapter ...
Essential oils: Art, Science, Agriculture, Industry & Entrepreneurship: A focus on the Asia-Pacific Region Sample Chapter ...
Essential oils: Art, Science, Agriculture, Industry & Entrepreneurship: A focus on the Asia-Pacific Region Sample Chapter ...
Essential oils: Art, Science, Agriculture, Industry & Entrepreneurship: A focus on the Asia-Pacific Region Sample Chapter ...
Essential oils: Art, Science, Agriculture, Industry & Entrepreneurship: A focus on the Asia-Pacific Region Sample Chapter ...
Essential oils: Art, Science, Agriculture, Industry & Entrepreneurship: A focus on the Asia-Pacific Region Sample Chapter ...
Essential oils: Art, Science, Agriculture, Industry & Entrepreneurship: A focus on the Asia-Pacific Region Sample Chapter ...
Essential oils: Art, Science, Agriculture, Industry & Entrepreneurship: A focus on the Asia-Pacific Region Sample Chapter ...
Essential oils: Art, Science, Agriculture, Industry & Entrepreneurship: A focus on the Asia-Pacific Region Sample Chapter ...
Essential oils: Art, Science, Agriculture, Industry & Entrepreneurship: A focus on the Asia-Pacific Region Sample Chapter ...
Essential oils: Art, Science, Agriculture, Industry & Entrepreneurship: A focus on the Asia-Pacific Region Sample Chapter ...
Essential oils: Art, Science, Agriculture, Industry & Entrepreneurship: A focus on the Asia-Pacific Region Sample Chapter ...
Essential oils: Art, Science, Agriculture, Industry & Entrepreneurship: A focus on the Asia-Pacific Region Sample Chapter ...
Essential oils: Art, Science, Agriculture, Industry & Entrepreneurship: A focus on the Asia-Pacific Region Sample Chapter ...
Essential oils: Art, Science, Agriculture, Industry & Entrepreneurship: A focus on the Asia-Pacific Region Sample Chapter ...
Essential oils: Art, Science, Agriculture, Industry & Entrepreneurship: A focus on the Asia-Pacific Region Sample Chapter ...
Essential oils: Art, Science, Agriculture, Industry & Entrepreneurship: A focus on the Asia-Pacific Region Sample Chapter ...
Essential oils: Art, Science, Agriculture, Industry & Entrepreneurship: A focus on the Asia-Pacific Region Sample Chapter ...
Essential oils: Art, Science, Agriculture, Industry & Entrepreneurship: A focus on the Asia-Pacific Region Sample Chapter ...
Essential oils: Art, Science, Agriculture, Industry & Entrepreneurship: A focus on the Asia-Pacific Region Sample Chapter ...
Essential oils: Art, Science, Agriculture, Industry & Entrepreneurship: A focus on the Asia-Pacific Region Sample Chapter ...
Essential oils: Art, Science, Agriculture, Industry & Entrepreneurship: A focus on the Asia-Pacific Region Sample Chapter ...
Essential oils: Art, Science, Agriculture, Industry & Entrepreneurship: A focus on the Asia-Pacific Region Sample Chapter ...
Essential oils: Art, Science, Agriculture, Industry & Entrepreneurship: A focus on the Asia-Pacific Region Sample Chapter ...
Essential oils: Art, Science, Agriculture, Industry & Entrepreneurship: A focus on the Asia-Pacific Region Sample Chapter ...
Essential oils: Art, Science, Agriculture, Industry & Entrepreneurship: A focus on the Asia-Pacific Region Sample Chapter ...
Essential oils: Art, Science, Agriculture, Industry & Entrepreneurship: A focus on the Asia-Pacific Region Sample Chapter ...
Essential oils: Art, Science, Agriculture, Industry & Entrepreneurship: A focus on the Asia-Pacific Region Sample Chapter ...
Essential oils: Art, Science, Agriculture, Industry & Entrepreneurship: A focus on the Asia-Pacific Region Sample Chapter ...
Essential oils: Art, Science, Agriculture, Industry & Entrepreneurship: A focus on the Asia-Pacific Region Sample Chapter ...
Essential oils: Art, Science, Agriculture, Industry & Entrepreneurship: A focus on the Asia-Pacific Region Sample Chapter ...
Essential oils: Art, Science, Agriculture, Industry & Entrepreneurship: A focus on the Asia-Pacific Region Sample Chapter ...
Essential oils: Art, Science, Agriculture, Industry & Entrepreneurship: A focus on the Asia-Pacific Region Sample Chapter ...
Essential oils: Art, Science, Agriculture, Industry & Entrepreneurship: A focus on the Asia-Pacific Region Sample Chapter ...
Essential oils: Art, Science, Agriculture, Industry & Entrepreneurship: A focus on the Asia-Pacific Region Sample Chapter ...
Essential oils: Art, Science, Agriculture, Industry & Entrepreneurship: A focus on the Asia-Pacific Region Sample Chapter ...
Essential oils: Art, Science, Agriculture, Industry & Entrepreneurship: A focus on the Asia-Pacific Region Sample Chapter ...
Essential oils: Art, Science, Agriculture, Industry & Entrepreneurship: A focus on the Asia-Pacific Region Sample Chapter ...
Essential oils: Art, Science, Agriculture, Industry & Entrepreneurship: A focus on the Asia-Pacific Region Sample Chapter ...
Essential oils: Art, Science, Agriculture, Industry & Entrepreneurship: A focus on the Asia-Pacific Region Sample Chapter ...
Essential oils: Art, Science, Agriculture, Industry & Entrepreneurship: A focus on the Asia-Pacific Region Sample Chapter ...
Essential oils: Art, Science, Agriculture, Industry & Entrepreneurship: A focus on the Asia-Pacific Region Sample Chapter ...
Essential oils: Art, Science, Agriculture, Industry & Entrepreneurship: A focus on the Asia-Pacific Region Sample Chapter ...
Essential oils: Art, Science, Agriculture, Industry & Entrepreneurship: A focus on the Asia-Pacific Region Sample Chapter ...
Essential oils: Art, Science, Agriculture, Industry & Entrepreneurship: A focus on the Asia-Pacific Region Sample Chapter ...
Essential oils: Art, Science, Agriculture, Industry & Entrepreneurship: A focus on the Asia-Pacific Region Sample Chapter ...
Essential oils: Art, Science, Agriculture, Industry & Entrepreneurship: A focus on the Asia-Pacific Region Sample Chapter ...
Essential oils: Art, Science, Agriculture, Industry & Entrepreneurship: A focus on the Asia-Pacific Region Sample Chapter ...
Essential oils: Art, Science, Agriculture, Industry & Entrepreneurship: A focus on the Asia-Pacific Region Sample Chapter ...
Essential oils: Art, Science, Agriculture, Industry & Entrepreneurship: A focus on the Asia-Pacific Region Sample Chapter ...
Essential oils: Art, Science, Agriculture, Industry & Entrepreneurship: A focus on the Asia-Pacific Region Sample Chapter ...
Essential oils: Art, Science, Agriculture, Industry & Entrepreneurship: A focus on the Asia-Pacific Region Sample Chapter ...
Essential oils: Art, Science, Agriculture, Industry & Entrepreneurship: A focus on the Asia-Pacific Region Sample Chapter ...
Essential oils: Art, Science, Agriculture, Industry & Entrepreneurship: A focus on the Asia-Pacific Region Sample Chapter ...
Essential oils: Art, Science, Agriculture, Industry & Entrepreneurship: A focus on the Asia-Pacific Region Sample Chapter ...
Essential oils: Art, Science, Agriculture, Industry & Entrepreneurship: A focus on the Asia-Pacific Region Sample Chapter ...
Essential oils: Art, Science, Agriculture, Industry & Entrepreneurship: A focus on the Asia-Pacific Region Sample Chapter ...
Essential oils: Art, Science, Agriculture, Industry & Entrepreneurship: A focus on the Asia-Pacific Region Sample Chapter ...
Essential oils: Art, Science, Agriculture, Industry & Entrepreneurship: A focus on the Asia-Pacific Region Sample Chapter ...
Essential oils: Art, Science, Agriculture, Industry & Entrepreneurship: A focus on the Asia-Pacific Region Sample Chapter ...
Essential oils: Art, Science, Agriculture, Industry & Entrepreneurship: A focus on the Asia-Pacific Region Sample Chapter ...
Essential oils: Art, Science, Agriculture, Industry & Entrepreneurship: A focus on the Asia-Pacific Region Sample Chapter ...
Essential oils: Art, Science, Agriculture, Industry & Entrepreneurship: A focus on the Asia-Pacific Region Sample Chapter ...
Essential oils: Art, Science, Agriculture, Industry & Entrepreneurship: A focus on the Asia-Pacific Region Sample Chapter ...
Essential oils: Art, Science, Agriculture, Industry & Entrepreneurship: A focus on the Asia-Pacific Region Sample Chapter ...
Essential oils: Art, Science, Agriculture, Industry & Entrepreneurship: A focus on the Asia-Pacific Region Sample Chapter ...
Essential oils: Art, Science, Agriculture, Industry & Entrepreneurship: A focus on the Asia-Pacific Region Sample Chapter ...
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Essential oils: Art, Science, Agriculture, Industry & Entrepreneurship: A focus on the Asia-Pacific Region Sample Chapter 9: The field development process

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  1. 1. Chapter 9 THE FIELD DEVELOPMENT PROCESS This chapter covers some of the important technical aspects of the field developmentprocess. The chapter begins with a discussion about the concept of agriculture as a system.The implications of climate change on agriculture are discussed. Plant metabolic pathwaysare reconsidered in reference to their importance to influencing field practices before thechapter commences a discussion on the field development phase proper. This chaptercontinues to describe each step of the development process, including land selection,propagation materials collection, the nursery, land preparation, planting and maintenance,harvesting and distillation. Good Agricultural Practice (GAP) is discussed before themethods of budgeting to determine financial feasibility of a project at the conclusion of thechapter. INTRODUCTION The fieldwork related to developing an essential oil as a commercial crop requires aninterdisciplinary approach. This requires the integration of botany, plant physiology,agronomy, engineering, chemistry and new product development skills, all within a businessorientated framework [1]. The last three chapters were concerned with what to produce andhow to market the potential end product. This chapter concerns itself with Where and how toproduce, while keeping economic viability in mind. Figure 9.1. shows the various stages ofthe field development process that must be considered [2]. AN AGRICULTURAL ENTERPRISE AS A SYSTEM Sustainable agriculture is now a major issue among academics, government, business,community groups and consumers around the world. This is reflected in the growth ofsustainable farming practices, the growth of organic markets, growing community interest inwhere products come from and changing government policies. Emerging markets based onthe ‘natural paradigm’ should embrace sustainability as a major objective. An agricultural enterprise is part of a complex ecological and sociological system, whichis influenced by interrelated sub-systems including, physical, environmental, biological andsocial systems. We have managed these systems through the current state of our collectiveknowledge to exploit economic opportunities within a competitive environment. Through the
  2. 2. 2 Murray Hunter‘green revolution’ of the 1960s improved genetic materials, mono-cropping, syntheticfertilisers, herbicides and pesticides, provided great improvements in productivity. Howeverthis dramatic increase in output led to a number of negative externalities which included soilerosion, loss of soil fertility, reduced biodiversity, pollution of ground water and rivers, whichled to long term environmental consequences and unsustainable production [3]. Thedevelopment of sustainable agriculture practices became popular in the 1970s as a passionateresponse to the above mentioned problems [4]. A new systems paradigm based on the twofollowing principals emerged; • Crops are developed with respect to nutrient and water cycles, energy flows, and the relationship between the target species and pests and competitors, and • The system is managed through strategic and tactical planning, resource allocation and financial and economic considerations, governed by goals, attitudes, knowledge and values of the manager, working within the eco-system [5]. The Field Development of a New Essential Oil Disciplines Basic Required Questions Marketing, Perfumer/flavourist, Screening and Selection Process botany, ethnobotany, (Chaps. 6,7,8) Agronomy, Food Tech. & Cosmetic Chem. What to Produce? Agronomy Botany Plant Physiology Project Preparation and Early Chemistry Work Flavour/Fragrance Cosmetic Science Where to Produce? Agricultural science Land Selection Economic geography Botany Development of Propagation How to Produce? Plant physiology Material Agronomy Biology Agronomy Entomology Development of Planting, Analytical chemistry Cultivation and Harvesting Engineering Techniques Chemical engineering Bio-chemistry Agronomy Development of Oil Extraction Analytical chemistry Techniques Agricultural engineering Market Strategies How to Market?Figure 9.1. The Field Development of a New Essential Oil.
  3. 3. Enterprise Viability and New Crop Potential 3 Infrastructure Government Regulation Positive Inputs Taxes & Conducive weather Water Negative Outputs subsidies Climate Or Sunshine Trade Floods, droughts, etc Nitrogen Runoffs, wastes, environment Agricultural inputs carbon Research Weather Fertilizers etc Rainfall Knowledge Wind Labour Sunshine UV radiation Temperature Some Humidity Resource inputs, Production Processes fertilizers, herbicides, recycling insecticides, machinery, back to Human research capabilities Farm size & layout system Habitisation Organisation & methods Knowledge Suitability of conditions Suppliers & contractors Pollution (air, land & water) Propagation Pollution Labour sources Attitudes and concerns Water resources Cultivation Positive Outputs (create hinterland where Products farm part of) Processing Physical Environment Customers Financing & Marketing Revenue flow various kinds of back to Soil capital Topography system Atmosphere Natural flora & Negative Inputs fauna habitat Business Urbanisation Adverse physical Environment Competition conditions Low prices Pests & diseases Markets Changing demand Pollution Finance patterns Heavy metals Trade environment An Agricultural Enterprise as a SystemFigure 9.2. An Agricultural Enterprise as a System. An illustration of the farm within an entire eco and human system is shown in Figure 9.2. This farming paradigm shifted from just trying to treat the symptoms through alleviationor suppression to treating and curing the actual sources of problems in agriculture. Thus undera systems context [6] the major tools of management became; 1. Enhancing the re-cycle potential of biomasses to optimise nutrient availability and balance, 2. Securing favourable soil conditions for crop growth through managing organic materials and biotic activity, 3. Minimising losses due to solar radiation, air and water through microclimate management, water harvesting and soil management, 4. Developing genetic and species diversification, and 5. Enhancing beneficial biological interactions through maximising agro-biodiversity to promote beneficial ecological processes [7]. These principals and strategies have to be tactically applied in different ways to variousfarming models, differentiated due to climate, geographic, social and organisational diversity,as Table 9.1. demonstrates [8]. However the aim of each type of system is the same; to reducethe dependency on nitrogen fertilisers, reduce the levels of residual phosphorous fertilisers,reduce dependency on herbicides, find ways to manage weeds, break pest and disease cycles,increase total system water use and protect against soil erosion, in a way that maintains goodcrop yields and quality [9].
  4. 4. 4 Murray Hunter Table 9.1. Major Eco-Systems, Production Systems and Organisation Major Eco- Production Organisational Form(s) System Type Systems 1. Arid Agro- Agro- a) small subsistence Ecosystem Horticulture- b) semi-subsistence, partly commercial farms pastoral c) Large family commercial farms along estate lines activities d) Commercial estates, mono-crop with hired management 2. Coastal Livestock, a) small subsistence Agro- fish, b) semi-subsistence, partly commercial farms Ecosystem agriculture and c) small commercial specialised family farms horticulture c) Large family commercial farms along estate lines d) Commercial estates, mono-crop with hired management 3. Hill and Agriculture, a) small subsistence Mountain horticulture b) semi-subsistence, partly commercial farms and livestock c) small commercial specialised family farms 4. Irrigated Rice-wheat, a) small subsistence Agro- sugar cane, b) semi-subsistence, partly commercial farms Ecosystem cotton, soy, c) small commercial specialised family farms dairy and fish c) Large family commercial farms along estate lines d) Commercial estates, mono-crop with hired management 5. Rainfed Arable a) small subsistence Agro- farming, agro- b)semi-subsistence, partly commercial farms Ecosystem forestry and c) small commercial specialised family farms livestock c) Large family commercial farms along estate lines d) Commercial estates, mono-crop with hired management The concepts contained within systems agriculture provide an appreciation of theinterrelationships between crops and farming variables. The objective of experimentation andresearch is to correlate productivity and sustainability during the field development process.In effect, the result of the field development process is to create a set of theories (oroperational practices) that will develop a sustainable farming system. Sustainability in theagricultural production process has commercial implications. It is becoming an importantissue on the minds of users, especially in regards to pesticide residuals [10], and is being usedby some producers as a point of product differentiation. CLIMATE CHANGE Global warming and climate change is full of academic and political controversy, wherefact and conjecture is fiercely debated [11]. Although evidence exists and is sometimesdramatically portrayed as signs of an impending global disaster, there are still scientists whoare disputing that the current temperature trends are within the bounds of natural changebased on historical data [12]. Conservative US politicians also dispute the issue where the USGovernment with Australia (until the election of a Labor Government in November 2007)
  5. 5. Enterprise Viability and New Crop Potential 5failed to sign the Kyoto Protocol, claiming the economic costs of achieving 1990 CO2emissions are too high. At the end of 2006, a film featuring the former Vice President of the United States Mr. AlGore, An Inconvenient Truth dramatically and graphically showed a string of naturaloccurrences which were attributed to climate change, caused primary by carbon dioxideemissions [13]. Mr. Gore in his documentary showed that 10 of the hottest years in historyhad occurred during the last 14 years, the occurrence of much stronger hurricanes/cyclonesand typhoons than ever before, more flooding and droughts across the globe, the permafrostin Siberia and Alaska melting, as well as the melting of the polar ice caps. Mr. Gore alsoshowed evidence that the white house (under the Bush administration) had arbitrarily changedsome of the conclusions of the EPA climate reports [14]. An Inconvenient Truth was releasedat a time which spurred on the arguments for action, but was also not without its criticism andfound to be flawed in some of its factualism [15]. Ironically just 24 hours after the Britishcourt ruling that there were nine factual inaccuracies in An Inconvenient Truth, Mr. Gore wasjointly awarded the Nobel Prize for peace jointly with the United Nations IntergovernmentalPanel on Climate Control (IPCC). It is not disputed that methane and carbon dioxide concentrations are continuing to rise inthe atmosphere and the Earth is currently undergoing a period of high temperatures. There aremany stories in the media about farming regions struggling with their traditional industrieslike the vineyards in Australia, South Africa and California, while at the same time, newregions are quickly developing new agricultural industries, like the wine industry in NovaScotia, due to the decline in frosts [16]. Wide evidence exists of loss of soil moisture due todehydration, rising land salinity levels in many dry land regions, increasing carbolic acid inthe rain changing pH levels in the soil, increased growth of algae, and the increasingincidence and threat of bush or wildfires around the world. An Australian CSIRO report put the above concerns to the Australian Government statingthat “…Australia is one of many global regions experiencing significant climate changes as aresult of global emissions of greenhouse gases (GHGs) from human activities” [17]. Thereport confirms that average temperatures have globally risen over the last 100 years andthere are marked declines in precipitation in some regional areas, while increases in others.The report concludes that even though initially there are some benefits of longer day periodand shorter winters, with increasing crop yields; rising temperatures, droughts and adverseweather conditions will negate these benefits and become a factor threatening the vitality ofagriculture in the future. A more recent report released by the IPCC based on actualmeasurements rather than projections, establishes that greenhouse gases in the atmosphere areincreasing much faster than previously estimated and are already over the threshold that couldbe potentially dangerous to climate change [18]. At the time of writing there are signs that political figures are slowly bringing the issueup more seriously, as is the case of China [19] and the US. However with the global financialcrisis taking most attention of World Governments, it is doubtful that any seriousinternational agreements can be made over the next couple of years. Some of the challenges that climate change may bring to agriculture and should beconsidered are; • Habitat Change: The habitat is already undergoing some changes [20], which is improving environmental conditions for some species, while at the same time
  6. 6. 6 Murray Hunter denigrating the environment for others. Some pests will become more evasive to crops, while others will disappear. There will be increased geographical scope for planting some crops, but a narrower the scope for others. The viability of some existing growing areas will be threatened [21]. For example, a 1.0 C. degree rise in average temperatures will chance core conditions for 25% of eucalypts in Australia. The consequences of this, is not currently known as to whether they will adapt new conditions or become threatened with area extinction [22]. • Loss of Arable Agricultural Land: Decreasing precipitation, increasing salinity and long droughts in areas adjacent to drylands is leading to a loss of arable farming lands in many continents [23]. • Increase in Adverse Weather Conditions: Weather conditions can be expected to be more abnormal in the future bringing floods and droughts to different geographical regions. The decrease of snow in alpine areas will create water management concerns in respect to drought and flood management, and • Increase of External “Natural” Threats: Bush or wild fires will increase bringing threats to farms and crops and require consideration in farm layout planning and management. At the field level crop stress will become a prime agronomic issue. Atmospheric warmingwill expose crops to higher temperatures, which will lead to changes in plant physiology atthe cellular level. Once optimal temperature ranges pass for specific plants, heat stress willdevelop, causing various plant metabolism changes that will slow down cell growthdramatically [24]. The effects of climate change on crops will be profound, not at least uponthe basic plant processes within the plant metabolism [25]. Plants have metabolite and growthresponses to salinity, heat stress, evaluated CO2 and drought (Table 9.2.), which would mostlikely lead to changes in whole plant carbon and nutrient budgeting, leading to changinggrowth patterns. Table 9.2. Summary of Plant Responses to Environmental Change Salinity Heat Stress Elevated CO2 Drought Primary Metabolites Slight Varying Unknown Strong relationship relationships relationship Secondary Metabolites Positive Positive Unknown Strong relationship relationship relationship Growth Strong Strong Unknown Strong relationship relationship relationship PROJECT PREPARATION AND EARLY WORK Project preparation and early work involves the determination of the major factors thatinfluence yield and oil quality. The analysis of the factors that lead to optimum plantproductivity is important in the field development stage. It is important to know how eachfactor interacts. The key to optimum productivity may rest on a single influencing factor.
  7. 7. Enterprise Viability and New Crop Potential 7Thus efforts to uplift yield and quality may have little effect until this single factor isaddressed. In other cases, two of more factors may be either co-limiting or co-synergists. Thefirst step in this investigation involves matching the climate, weather, moisture needs of theproposed crop to the locality available. There is a need to understand the basic paths through which aromatic materials developwithin the plant metabolism. This will assist in the development of nutrient and moistureregimes and the timing of harvest. Paramount to good yields and quality is the quality of thegenetic planting material. The selection of the correct material for cultivation is important. CLIMATE AND MOISTURE Temperature and moisture are two of the most important factors regulating plant growth.Plant adaptability to temperature is the parameter that has most influence upon its growth ratein a new location. Moisture is a factor that greatly influences the vigour and vitality of theplant. Plants originating from various indigenous environments exist with particular sets ofgrowth and behaviour characteristics. The basic plant climatic zones can be describes as; • Tropical Zone where all mean air temperatures are above 18-20°C, where no frosts exist. This area covers the Earth between the Tropic of Capricorn and Tropic of Cancer (23.5°S & 23.5°N). • Tropical Monsoonal Zone where part of the tropical zone which has a distinct dry season of 3-5 months, where the dry seasons usually increase mean temperature two or three degrees above the wet seasons. Dry seasons are usually cloudless or spasmodically clouded days and these zones are coastal along the equatorial region. • Sub-tropical Zone where the coldest month of the year would have a mean temperature above 16°C, where only occasional frosts would occur. This zone occurs between 23.5-30°+ latitudes. • Arid-Dryland Zones where mean temperatures are above 18°C and there is very little precipitation. Arid-dryland zones are sometimes accompanied with soil salinity, which together with high temperatures and salinity make the land marginal for agriculture. • Temperate Zones where temperatures are high enough for around 6-7 months each year for active plant growth. These zones occur above the mid 30°s latitudes and in the mountainous areas of sub-tropical and tropical zones. • Boreal Zones where mean temperatures are around 10°C and may warm up enough only for plants to grow two to three months a year. Boreal zones also exist in high altitude areas of the other zones. Examples of some types of crops that grow in these zones are indicated in Table 9.3. Plants introduced into new areas will exhibit different phyto-synthetic responses (theprocess of bonding CO2 with H2O to make basic sugars and oxygen). This is directly relatedto biomass yields in the field [26]. Plants that have difficulty adapting will become stressed,
  8. 8. 8 Murray Hunterso temperature is a major factor in adaptability. Plant adaptation to higher temperatures isrelated to photosynthesis efficiency. Four basic photosynthesis systems exist in plants [27]; Table 9.3. Examples of Crops Grown in Different Climate Zones Zone Crops Aromatics Comments Tropical Palm oil, Citronella, Ylang The main zone for chill-sensitive rubber, cocoa, Ylang, Vetiver, evergreen perennials. Crops that benefit banana, lemongrass, from chills like apples are not ginger, vanilla commercially successful in this region. Warm season annuls successful, whereas cool-season annuls not commercially successful. Monsoonal Rubber, rice, Patchouli With irrigation this region is similar to some citrus the tropical zone, although crops that fruits, mango need flowering to fruit like mangoes grow successfully in this region. Sub-tropical Sugar, maize, Citrus, petitgrain, Areas around the Mediterranean Sea are sunflower, neroli, tea tree sub-tropical as well as most of the oranges Eastern Seaboard of Australia, above Sydney until the Tropic of Capricorn. A broad range of species grow successfully; evergreens, deciduous trees and warm season annuls. Some tropical and temperate crops are successful, near their respective temperature ranges, i.e, cool season annuls. Arid- Some citrus Eucalyptus High temperatures and salinity make the Dryland fruits in species land marginal for agriculture, unless irrigated areas are irrigated. areas. Hoodia cacti species in Southern Africa. Temperate Potatoes, Most herbaceous Cool season annuls from spring to lettuce, oils, peppermint, autumn. Winter can cause dormancy. carrots, Lavender, etc Some warm season annuls can be apples, pears successful if temperatures are high enough for a sufficient period of time. Deciduous trees that require chills like apples and pears very successful, as well as frost resistant perennials and conifers.
  9. 9. 9 Temperature Table 9.4. Temperature, Rainfall and General Habitat Parameters for Some Plant Botanical Name Habitat Range Rainfall Lat. Altitude Diurnal Optimal Max. Range (mm) Radiation Lavender Lavendula Mediterran 15°C 28°C 7°C 24°C 500mm 1000m 35- <1700m Direct Sunlight Angelica Angelica Temperate 5°C 19°C - - 600mm 1300m 30- 700- - Ylang Ylang Cananga odorata Tropical - - 21°C 32°C 1500m 2000m 10- <400m Direct after maturity Lemon Citrus limon Mediterran 15°C 18°C - - 250mm 1250m 40°S- - Direct exposureEnterprise Viability and New Crop Potential Coriander Coriandrum sativum Versatile 6°C 17°C 4°C 28°C+ 1500m 2500m 40°S- <2200m Direct exposure Lime Citrus aurantifolia Tropical 22°C 28°C 18°C 32°C 1250m 2500m 30°S- <2200m Direct Sunlight Cumin Cuminum cyminum Sub- 17°C 26°C 9°C 26°C 800mm 2700m Along lowlands Direct exposure Galanga Alpinia galanga Tropical 24°C 30°C 18°C 34◦C 1500m 3000m 20° N&S lowlands Partial Shade Aromatic Plants Lemon Balm Melissa officinalis Temperate 14°C 25°C 6°C 30°C 500mm 1300m 30- <1700m Direct exposure Sandalwood Santalum album Arid- 22°C 30°C 10°C 38°C 450mm 3000m 20° N&S <2500m Direct exposure Aloe Aquilaria Tropical 20°C 22°C 18°C 32°C - - 0- <1000m Direct sunlight Dill Anethum graveolens Temperate 15°C 18°C 6°C 26°C 500mm 1700m 28- - Direct sunlight Cardamom Elettaria Temp/Trop - - 10°C 35°C 1500m 1700m 5- <1400m Shaded areas Hyssop Hyssopus officinalis Mediterran 10°C 24°C 7°C 36°C 600mm 1000m 25-66° <2000m Direct sunlight Geranium Pelargonium Temp/Sub- 10°C 32°C 30-50° <1200m Light shade Perilla Perilla frutescens Tropical 0-50°N Light shade Rue Ruta graveolens Mediterran 17°C 26°C 4°C 30°C 500mm 1500m 30-45°N Direct sunshine Vanilla Vanilla planifolia Tropical 21°C 30°C 10°C 33°C 1500m 3000m 20°S- <700m Part shade Artemisia Artemisia vulgaris Tem/tropic 0-60°N Direct sunlight Tea tree Melaleuca Sub- 21°C 30°C 10°C 45°C 800mm 3000m 0- <700m Direct sunlight Caraway Carum carvi Temperate 16°C 20°C 7°C 26°C 600mm 1300m 45-60°N Direct sunlight Lemongrass Cymbopogon Grasslands 24◦C 30°C 18°C 34◦C 1500m 3000m 20° N&S <1400m Direct Sunlight
  10. 10. 10 Murray Hunter • The C3 plants incorporate CO2 into 3-carbon compounds. The stomata (pores in the leaves through which CO2 is consumed and O2 expelled during photosynthesis) is open during daylight hours, the enzyme rubisco directly uptakes CO2. This is the most efficient photosynthesis mechanism within the plant kingdom and works well during cool and moist conditions under normal light as less energy is required. Most plants are C3. • The C4 plants incorporate CO2 into a 4-carbon compound. The stomata are open only during daylight hours. The vehicle for CO2 uptake is PEP carboxylase which transfers it directly to rubisco for processing, which is fast and moisture efficient. There are numerous species with this type of respiratory system, mainly plants with habitats in warmer conditions, including most tropical grasses. • Plants where photosynthesis alternates between the C3/C4 mechanisms, and • Crassulacean Acid Metabolism (CAM) photosynthesis where CO2 is stored as acid before photosynthesis. In this mechanism the stomata opens during darkness where evaporation rates are usually lower. During daylight hours rubisco breaks down the CO2 for photosynthesis. This mechanism is more moisture efficient than C3 plants due to night collection of CO2. When droughts occur the stomata remains closed and the acids are utilised as needed for photosynthesis. Cacti are CAM plants. The phytosynthesis systems of plants will strongly influence plant adaptation to newenvironments. Among the C3 species, the herbaceous annuls, evergreens and non-leguminousplants will adapt better than the perennial woody species, deciduous trees and leguminousplants that fix nitrogen [28]. C4 species should adapt to higher temperature conditions betterthan the other metabolisms. A plant genotype may have a number of phenotype varianceswhich exhibit different tolerances to different climatic conditions [28]. Plants are capable ofadapting to different habitats, however the introduction of new crops from cooler regionswhere the photosynthesis system may be very sensitive to heat, may require breeding toimprove tolerance in hot weather [29]. Potential upper temperature limits will depend on the level of plant stress to thetemperature range in the new environment. Stress is the key issue to monitor. At the lowertemperature levels, below 10°C plant growth becomes severely retarded. Effective growthceases around 7°C for most plants [30]. Thus the most suitable upper and lower temperaturelevels for plants needs to be ascertained before introduction. The mean temperatures, sunlightand day length will define the maximum limits of potential productivity, while the lowtemperatures and moisture levels through precipitations will define the restrictions on plantgrowth. Table 9.4. shows some temperature and other habitat parameters for a selection ofaromatic plants [31]. A basic evaluation of moisture requires the review of effective rainfall. Effective rainfallis the amount of rain necessary to commence and sustain plant growth. However somerainfall is lost in evaporation (evapotranspiration) and run-off. Thus a quick measure ofdetermining the rainfall needed to start and sustain plant growth is to add 50% to necessarymoisture required by a particular plant and compare this figure to the mean rainfall figures ofthe area in question. Historical data for a long period is best to determine the mean and droughts must be takeninto account for drainage and irrigation planning during the land preparation stage.
  11. 11. Enterprise Viability and New Crop Potential 11 However the above analysis can be misleading as it lacks sensitivity, not taking intoaccount the intensity and distribution of rainfall during the year. In arid and monsoonalregions growth after rain can be vigorous, so additional analysis should be undertaken todetermine the annual growing season. Issues such as the number of dry days in succession areimportant for wilting and growth inhibition. Soil moisture absorption ability, infiltration rate,and the topographic features such as slope, ground cover, etc., also influences how muchrainfall actually benefits the crop. These factors also bring up issues of potential for root rot,pathogen development, competitive weed growth and their influences upon growth rates. A process to make an assessment about the suitability of a particular area for a specifiedcrop would involve the following steps: 1. Obtain weather station and climatic data for the area. Obtain daylight and dark hours for the year. Obtain the number of rain/dry days averages for each year. 2. Analyse the data to obtain mean and extreme temperatures on a daylight and nightly basis for each year. Calculate the effective rainfall and the effective growing periods. 3. Compare this data to the plant habitat data available to see if there is a match. 4. If there is a mismatch, make predictions about the potential adaptability of the plant to the new environment (this may require some garden trials to assist and confirm deductions) 5. Look around for similar plant species growing in the area and observe their growth behaviour and growth periods. 6. Make predictions about possible planting, growth and harvest times based on the above information. Some other issues to consider are; • The effect of dry seasons on flora and ground cover as it may have a tendency to put most plants into a dormant state, where annuls without cover crops may become stressed, • Storm activity may cause high winds and lightening strikes, which can initiate wildfires, and • Excess rainfall can cause heavy erosion and loss of top soils with channel run-offs, leading to loss of organic matter in the soil. PLANT AROMATIC MATERIAL COMPOSITION AND PATHWAYS An essential oil or aromatic material within a plant is primarily a substance comprising ofvolatile compounds which are formed through the plant metabolism. The plant metabolism isinfluenced by both intrinsic and extrinsic factors from the field perspective. The chemical,physical and olfactory characteristics of the essential oil are the factors that contribute to theoverall quality of the product. Yield has an important bearing on the overall economics of acrop. The regulatory framework prescribes what is and is not allowable in the composition ofan essential oil. Thus the starting point in physical crop development is a full analysis of the
  12. 12. 12 Murray Hunteressential oil and a mapping of the metabolic pathways that produce the composition theessential oil. The sensitivity and methodology of analytical phytochemistry has improved in leaps andbounds over the last decade to provide an almost complete analysis (80-90%) today,compared to around 40-60% a decade ago for very complex compounds. Table 9.5. shows asummary of the composition of a tansy oil chemotype (Tanacetum vulgare L.) [32]. It isimportant to consider the trace and minor compounds within varying varieties of a genotypeand within the desired chemotype, because of their contribution to odour profile, which maybe desirable or undesirable in the product. This will be discussed shortly. Theoretical production ecology is a method based on a systems approach to agriculture tomanage crop productivity through quantitative modals. This method identifies the variablesand processes related to plant growth and seeks to find the optimum field methods to managethem. A study of the plant physiological and biochemical processes is the foundation uponwhich field management parameters can be developed and set. Thus, the composition analysisof the essential oil should lead to a study of how the important compounds are formedthrough the metabolic pathways specific to the plant as shown in Figure 9.3. Table 9.5. Composition of a Chemotype of Tanacetum vulgare L. (Tansy) a-pinene 5.0% Camphene 1-2% Sabine 1.5% Β-pinene >2.0% Myrcene 0.5% a-terpinene 0.5% Cymene 0.7% 1,8-cineole 16.0% Gamma-terpinene 0.9% Terpinolene 0.1% Camphor 16.0% Borneol 1.8% Terpinene-4-ol 2.4% a-terpineol 1.6% Mytenal 3.0% Mytenol 25.0% Isobornyl acetate 0.5% Trans-Sabinyl acetate 2.5% a-Copeane 0.3% Caryophyllene 0.3% Spathulenol 1.3% Caryophyllene oxide 1.0% Vulgarol 1.0%
  13. 13. Enterprise Viability and New Crop Potential 13 Carbon dioxide Glycolysis Glucose 2 Acetyl CoA Fatty acid Acetoacetyl-CoA thiolase Acetocetyl CoA HMGS-CoA syntesis 3-hydroxy-3-methyl-glutaryl-CoA (HMG-CoA) HMGL-CoA lyase HMGR-CoA reductase Mevalonate Cytokinins Isopentyl adenine Mevalonate pyrophosphate IPP isomerase rubber Isopentenyl pyrophosphate (IPP) DMAPP (C5) Monoterpene synthases and cyclase Geranyl pyrophosphate (C10) Monoterpenes prenyltransferase Farnesyl pyrophosphate (FPP) (C15) Sesquiterpenes Polyprenols Sesquiterpene Farnesylated Synthesis & proteins Cyclase Diterpene synthase & Cyclase Squalene syntase Geranyl geranylpyrophosphate (C20) Squalene (C30) Diterpenes Sterols Carotenoids Saponins Abscisic acid Hormones Chlorophyll Lipoproteins Vitamin KFigure 9.3. The General Plant Metabolic Pathways for Secondary Metabolite Production [33].
  14. 14. 14 Murray Hunter IPP DMPP Isomerization Geranyl-PP (+)-3S-Linayl-PP Monoterpene cyclase (-)-Boynyl-PP (-)-Camphene (+)-Isobornyl acetate (-)-Camphor Dehydrogenase (-)-Bornyl (-)-Camphor Dehydrogenase (+)-cis-sabinol (+)-Sabinone (+)-3-Thujone (a-thujone) (-)-3-Isothujone (ß-thujone)Figure 9.4. The Specific Pathway for the Production of a- and β-Thujone [34]. Investigation of the compounds found in an essential oil can lead to the mapping ofspecific pathways to the formation of important compounds as is shown in the example of a-and β-thujone production within the plant metabolism, as shown in Figure 9.4. Through mapping out the specific pathways, the interrelationships between the variouscompounds in the essential oil are shown, either as products of, or precursors for. Thisspecific pathway map can provide insights into how the various compounds in the essentialoil are formed and perhaps provide some keys as to how to manage optimum quality andyield, through specific nutrition regimes, crop maintenance, harvesting and extraction, whenexamined with the parameters in production ecology. A production ecology model wouldexamine the factors of heat, light, water and soil nutrients upon the plant metabolism andproduction of desired compounds within the plants. Then it is a matter of trying to determinewhat will be the optimal set of practices to produce the most desirable quality/biomass set.
  15. 15. Enterprise Viability and New Crop Potential 15 SELECTION AND ACQUISITION OF GENETIC MATERIAL FOR PLANTING The correct selection of genetic material for planting and cultivation is crucial to theproject. Many projects have failed because the selected material was the wrong chemotype orwas of poor quality, leading to the production of a commercially unsuitable material. Tansy is a perennial herbaceous flowering plant in Europe, the United States and Asia.More than five specific chemotype deviations from the main genotype have been reportedwith a number of sub-chemotypes [35]. Within a small geographical distance, chemo-diversity is large. Figure 9.5. depicts the reported chemical diversity of Tanacetum vulgare inNorthern Europe. Chemotype variation is widespread through the plant kingdom, where many speciescontain chemotypes that are very different in composition from each other as a summary ofAustralian species in Table 9.6. indicates [36]. There are essential oils on the market that are claimed to orginate from the samebotanical species but display very distinct and different characteristics. For example this is thecase with basil oil (Ocimum basilicum L.) where a number of products from different sourcesare on the market with different chemical and olfactory profiles. Table 9.7. shows thedifference in major chemical constituents of basil oil from five different sources with adescription of their olfactory profiles [37].Figure 9.5. Chemotype Variances within the Genotype Tanacetum vulgare L.
  16. 16. 16 Murray Hunter Table 9.6. A Summary List of Australian Species with Chemotype Variations Species Chemotype Major Individual Components of Leaf Oil Eucalyptus nova-anglica No. 1 E-nerodial 77% No. 2 a- & β-eudesmol 42% No. 3 aromadendrene 33% Eucalyptus camphora No. 1 1,8-Cineole, Limonene 70% & 5% No. 2 1,8-Cineole, a-Pinene 84% & 7.8% No. 3 1,8-Cineole, eudesmol 56% & 25% No. 4 Eudesmol, p-Cymene 46% & 15% Eucalyptus cloeziana No. 1 a-Pinene, β-Pinene 78% & 6% No. 2 Tasmanone 96.4% Eucalyptus crebra No. 1 a-Pinene, β-Pinene, 26%, 30%, Limonene, Aromadendrene, 7%, 5% & globulol 12.5% No. 2 1,8-Cineole 65% Eucalyptus dawsonii No. 1 Isobicyclogermacral 44% No. 2 Elemol, Eudesmol 16% & 63% Eucalyptus No. 1 P-Cymene 33% quadrangulata No. 2 a-Pinene, 1,8-Cineole, γ- 10%, 25%, Terpinene, p-Cymene 19% & 17% No. 3 a-Pinene, 1,8-Cineole 25% & 55% Eucalyptus radiata No. 1 a-Pinene, Limonene, 1,8- 14%, 5% & Cineole 71% No. 2 a-phellandrene, p-cymene, 18%, 14% & 1,8-Cineole 13% Melaleuca viridiflora No. 1 E-methyl cinnamate 80% No. 2 1,8-Cineole 48% No. (Var. 2) a-Pinene, 1,8-Cineole, 9%, 0.3% & terpinolene 32% No. 2 (Var. 3) a-Pinene, 1,8-Cineole 29% & 11% Melaleuca citrolens No. 1 Neral, Geranial <40% No. 2 Citronellal, Neral & geranial 20-30% No. 3 1,8-Cineole 40% Melaleuca ericifolia No. 1 d-Linalool <50% No. 2 1,8-Cineole <60% Melaleuca quinquenervia No. 1 1,8-Cineole, viridiflorol No. 2 E-Nerolidol <95% Backhousia anisata No. 1 E-Anethole <95% No. 2 Methyl chavicol <78% Backhousia citriodora No. 1 Neral & Geranial >90% No. 2 (-)-Citronellal 85-90% Leptospermum No. 1 Alpha, beta and gamma >60% myrtifolium eudesmol No. 2 E,E-Farnesol 56% Leptospermum petersonii No. 1 Neral/gernaial and citronellal <80% No. 2 Γ-Terpinene and terpinolene
  17. 17. Enterprise Viability and New Crop Potential 17 No. 3 Germacrene-D, Bicyclogermacrene & Spathulenol Archirhodomyrtus No. 1 E-β-Ocimene 68-88% beckleri No. 2 a-, β and γ-eudesmol No. 3 Geraniol/geranyl acetate 70% Cryptocarya No. 1 Benzyl Benzoate, cunninghamii bicyclogermacrene No. 2 6-nonyl-5,6-dihydro-2H- 78-88% pyran-2-one Neolitsea dealbata No. 1 a-, β and γ-eudesmol <70% No. 2 Germacrone and Furanogermacrone <90% Austromatthea elegans No. 1 Benzyl benzoate <97% No. 2 Benzyl Salicylate 80% Table 9.7. Different Major Chemical and Olfactory Profiles of Five Basil Oils Sample Linalool Methyl Olfactory Profile chavical India 14.2% 77.5% A grassy herbaceous and mildly spicy predominating note, with an herbaceous subsidiary note; back notes slightly fruity. French 55.3% 10.9% A smooth fresh and diffusive herbaceous note with harmonized cool anisic and slightly balsamic subsidiary notes and warm woody back notes. Australian 34.3% 34.7% A clean vegetable type note with a cool herbaceous menthol-like subsidiary note; a green and grassy back note. Seychelles 27.7% 40.2% A sharp diffusive clean grassy herbaceous note, with a fruity anisic subsidiary note and a very slightly camphoraceous back note. Reunion 3.4% 75.7% A sharp, if not somewhat dry, anisic note; the (Australian subsidiary notes were herbaceous with a slight grown) sweet camphoraceous floral back note. Chemical constituent variance through a natural population of plants is thought to be theresult of a number of factors. Morphological and thus chemical variation of a genotype can berelated to soil moisture where differing vegetative environments would be a tell tail sign ofthis condition [28]. The level and type of nutrients in the soil affects the level of variouschemical constituents within plants [39]. Soil topography such as natural drainage [40] andstatus of the land (cleared or natural habitat) would also influence chemistry and oil content[41]. Certain plants may exhibit varying tolerance to different soil pH [42] and tolerance tocold [43]. Climatic factors also influence variation, where Brophy and Dorland found distinctvariances in the main chemical constituents (1,8-Cineole and linalool) of Melaleuca ericifoliaaccording to latitudinal changes [44]. Studies of other trees (Melaleuca quinquenervia)
  18. 18. 18 Murray Hunterindicate that abrupt changes in climate can be correlated with chemical variation in naturalpopulations [45]. Plants with similar chemical properties tend to cluster together in locationsof similar topography [46]. When bio-prospecting for genetic material it is desirable to select plants that can providethe best possible leaf mass with a high oil concentration in the leaves, good coppicing ability(tree crops), resistance to pests and diseases, broad topography and weather adaptability andof a desirable oil quality [47]. A plant variety study is necessary to evaluate differentcultivars. It is best to survey a number of natural stands not only in the immediate vicinity,but in other locations around the country to obtain a wider variety of genetic characteristics.Within a single stand, survey plants at least 50m apart so sampling does not include siblings.Also include sampling of plants in different environments (soils, etc.) and select thedomineering ones within each stand. Seeking plant genetic diversity in seed collection is onemethod of creating a crop that has some protection against pest and diseases and generategood re-growth after harvesting.Seed Collection Seeds undergo a growth cycle within the ovules of the female plant after they have beenfertilized by a male plant or alternatively a plant may fertilize itself from its own pollen.Seeds should only be collected when they reach full maturity and are pollinated. Seeds areripe when the pods turn green to brown or white and are ready to be dispersed from the plant,i.e., the seeds in the flower begin to release themselves from its attachments and havechanged colour from green to brownish white, or the fruit drops from the tree. Flowering andfruiting will occur at various times of the year, so regular visits to natural stands are necessaryto determine the seasons. Genetic planting material includes seeds, roots, rhizomes, bulbs or vegetative cuttings.The basic equipment necessary for seed collection includes a large scissors, raw materialcollection bags, drop cloths or trays to collect seeds falling from the tree, some tin plate witha hammer and nails to mark trees, field distillation equipment, sample bottles, a GPS to take amarking, a camera and a marking pen to mark samples. The general method of collectinggenetic material from the wild would be as follows: 1. A general survey of natural stands over a wide as possible geographic area is necessary to sample as much genetic diversity as possible. This is a time consuming activity, as each site will require a number of sample distillations and analysis at a latter period. Each plant where a sample distillation is made should be marked, photographed and a small voucher sample taken. This process will collect an enormous amount of quantitative data to analyse, for example 10 natural stands taking 20 samples will provide 2000 pieces of data to review. The following information should also be gathered about each site; a) Information about prior land use, any fertiliser or other chemical application to the area, general soil profiles, type of vegetation in the area, surrounding topography and land use, source of upstream water, etc., b) Voucher specimens of each plant sampled taken so it can be botanically identified as to genus, species, and variety, and
  19. 19. Enterprise Viability and New Crop Potential 19 c) Distillation time taken, the part of plant the leaf collected for distillation sampling and yield. 2. Analyse the data collected to identify a number of potential plants for seed collection based on oil analysis, yield, and plant vitality. Ensure that the final selection is a balanced cross section of the natural stands and not too skewered a cluster. 3. Revisit each site to make a final selection of between 50-100 plants to collect seed. Evaluate seeding, flowering and fruiting times for each stand. 4. Seed collection should be undertaken when seeds are mature and there are dry conditions Ensure seeds are taken from the top, sides and bottom of the plant so maximum diversity is obtained. Branches can be cut near seed pods or flowers onto a tray or drop sheet to collect separating seeds during the disturbance. Fruit should only be collected from the ground before rot and decay sets in. Seeds and fruits collected should be packed into separate bags, ensuring there is not cross sample contamination for separation, drying, sorting and storage. 5. Seeds should be separated from the rest of the plant through vibrating the plant material across chicken wire or a strainer on top of paper, a drop mat or a lighted laminate table top (aspirator) in a specifically set up lab. Raw seeds can then be dried in partial shade or air dried. A roller can be used to separate seeds from their fruits, washed to remove any fibrous material which may contain germination inhibitors with water before drying. The drying phase is critical to seed quality and should not be done too quickly, as this will damage or kill the seed. Some moisture should be retained in the seeds. 6. Once seeds have been dried, use a tweezers to remove any foreign matter and bag the seed in paper or a sealed ziplock plastic bag (if air dried) for storage. The most viable seeds are those that are of good size, relative weight, shinny, with somebody around the embryo. Good seed will also exhibit much more strength than dead or overdried seed. Seeds can be graded according the above criteria, separating the most viable seedsfrom undersized, underweight, immature and deformed seeds, further improving the qualityof the seed. Once seeds are sealed and stored, relatively constant temperatures should bemaintained. If stored in paper bags, humidity should be fairly constant around 50%. Freezingshould be avoided as changing moisture state can damage the seeds. Refrigeration in a crisperis the best option to prolong useable life. Some seeds need a cold environment as a primer toreplicate winter periods. To maintain viability, seeds must maintain their dormancy to prevent them from dying.Seed deterioration occurs quickest under high temperatures and high humidity. To maintaindormancy within a seed, there must some moisture remaining. The level of moisture in theseed will have some influence on how long the seed will remain viable and at whattemperatures and humidity it is safe to store it at [48]. For short term use, seeds should bestored with maximum moisture levels. Seed lifespan can vary from a few weeks to hundredsof years. Those with high oil or lipid content will tend to last only a few months [49].Recalcitrant seeds which occur in woody species last only a few weeks unlike orthodox seedsin other species. Recalcitrant seeds tend to be large and fleshy and cannot be dried or cooledwithout being killed. These are mainly tropical species like cocoa and rubber. The advantage of undertaking seed collection is that seed quality and the source isknown. Some commercial or contract seed collectors may collect seeds from a single tree, or
  20. 20. 20 Murray Huntergroup of trees, before seeds fully mature. However there are numerous commercial seedtraders who specialize in particular seeds who can supply seed according to specifications. Bio-prospecting for genetic material has become an ethical and political issue, especiallyconcerning the issues of the rights of indigenous communities. There have been many casesof genetic materials identified from ethnobotanical information, which has been utilized bycompanies for profit without any benefits returning back to the original communities.Moreover, some companies have taken over patent rights on certain indigenous trees withoutany prior arrangement with indigenous peoples, like the W R Grace patent on herbicidalactivity of neem [50]. Many of these activities are now being successfully challenged incourts [51].Improvement of Genetic Material through Recurrent Selection Generally plants propagated by seed are genetically diverse due to the genetic diversity ofparent plants where the seeds have been collected. This should (if plants are of the samechemotype) result in minor variances in yields and oil composition through a field crop. Seedquality can be improved through selecting seeds based on selected genetic characteristics thatare desirable to increase the quality and yields of a crop. The general principal of an index selection program is to select plants from a populationaccording to a selected single or number of characteristics. The process of Index Selectiontaking seeds from natural stands or from diverse commercial cultivars and planted in seedorchards and a selection made each generation. Poor performing trees eliminated according toa statistically analysed set of complex criteria [52]. These plants become the parents of thenext generation, where a further selection is made, thus improving the target characteristic.This process narrows down the seed material to a set of genetically superior trees, wherefaster coppice growth, higher yields and oil quality are sort. The Index Selection process can take many years and require committed resources toundertake the required measurements for statistical analysis. The breeding process can bemore complex through a combined index selection program, weighting various characteristicssuch as composition, yield, coppice and biomass. In developing an index protocol it isnecessary to examine potential correlations between individual traits and weight themaccording to importance and degree of correlation [53]. Quicker results can be obtainedthrough breeding for single, rather than multiple traits as there are often negative correlationsbetween some variables. Genetic gains in individual traits often diminish as more traits areselected [54]. This method was successfully utilized to improve the overall genetic quality ofseed in the Australian tea tree industry over the last decade. Selective plant breeding is a long term process of is an activity that usually continues intandem with an emerging industry. Plant material can also be improved through a number ofvariances of index selection including cross pollination of germplasm, followed by recurrentprogeny selection and evaluation of desired characteristics (i.e., yield, composition, droughtresistance, etc) and DNA marker assisted selection (MAS) of plants with genes that displayspecified characteristics [55]. A simple Index Selection project path is shown in Figure 9.6.
  21. 21. Enterprise Viability and New Crop Potential 21 Propagation Base Population Breeding Population Population Seed Nursery Seed collected Established with a Seed Nursery with from selected number of reduced number natural stands ‘families” of ‘families” Seed release Emphasis on collecting a diverse genetic sampling Trees eliminated according to a complex set of criteria Replanting for including growth parameters, further selection biomass, yield, oil constituent markers, re-growth, etc.Figure 9.6. A Simplified Index Selection Strategy for Genetic Crop Improvement. An Index Selection program whether through seed or vegetative cutting approaches, or amixture of the two, will improve yields over wild plants [56]. This breeding strategy isadvantageous in improving genetic material from natural stands of plants for field cultivation.This would have potential application in the development of essential oil crops currently wildharvested or yet to be domesticated.Land Selection Land has a paramount influence on the whole viability of any project. The land willgreatly define both the opportunities and limitations upon the project. There may be a choicein location, as would be in the case with an estate company land bank or the ability topurchase new land. In other cases the physical location of the land is set, as it is a family or anexisting farm. With community projects, the land maybe a parcel of communitysmallholdings, grouped together by agreement. An individual piece of land has a unique set of characteristics, surrounded by a socio-ecological system. These characteristics will either assist or hinder development and as suchmust be examined in the light of any proposed future project. In addition to the physical andclimatic variables, the cost of land in both financial and opportunity terms represents a largeoutlay of financial and other resources, which creates a large exit barrier should failure occur.In terms of opportunity cost, any activity involves the weighing up of alternative uses, prices,costs, risks and profits. Lands costs, both financially and in terms of opportunities andlimitations vary widely and comparisons are necessary before making any final decisions[57]. This section will briefly outline the issues that should be assessed before any finalcommitment is undertaken. Any agricultural enterprise will be subject to constraints and incentives based on national,regional or provincial and local government philosophies, laws and regulations. These issuescan either add substantially to the cost of a project through taxes, occupational health and
  22. 22. 22 Murray Huntersafety, environment protection, water management, building and fire regulations, or lowercosts through incentives, grants or soft loans to agriculture. Salinity, drought, reforestationissues are putting many governments in the position where they must further regulate andrestrict potential activities, and these implications must be considered in costing andappraisal. Zoning laws may have both a present and future influence upon an enterprise. It isimportant to know the current zoning and how far is the land from or adjacent to a town orcity? Can the land be rezoned for housing or industry in the future? This will influence thevalue (cost) of the land, thus return on assets. Finally, security of tenure is a consideration. Is the land owned, leased, granted throughtime based tenure? Are there any revocation mechanisms in any tenure documents? The factors to consider in land selection are listed below as follows; • Socio-Economic Environment a) General land use and settlement in the immediate region b) Drivers of the local economy c) Patterns of crop specialization d) Townships and rural population e) General economic infrastructure f) Distance to railway/port/airport facilities g) Transport costs h) Available amenities and reliability (electricity, water, etc) i) Agricultural extension in region j) Agricultural research in region • Overall Land Topography-Ecology a) General topography (slopes, rivers, dams, undulation, hills, valleys, etc.) b) Total area available (excluding dams, waterways, throughways, unusable areas) c) Existing land use and vegetation d) Existing fauna and livestock e) Catchment and water storage areas f) Drainage and flood propensity g) Drainage and irrigation infrastructure h) Drought probability i) Internal road grid j) Activities on adjoining properties k) Catchment areas of upstream creeks, rivers and waterways l) Pest and disease assessment m) Altitude n) Previous use of land o) Scenic potential • Soil Type, Texture and Characteristics a) Type b) Texture c) Organic matter content d) pH e) Flow and retention of ground moisture f) Propensity to waterlog
  23. 23. Enterprise Viability and New Crop Potential 23 g) Degradation (salinity, acidity, erosion) • Infrastructure a) Existing buildings, premise, processing facilities b) Road access c) Fencing d) Waste management e) Ease of building required infrastructure f) Fire management • Potential Crop Cycle a) Timing and duration of planting, growth and harvest periods b) Potential rates of growth c) Number of harvests per year • Procurement a) Access to spare parts supply b) Available source of economic fuel for extraction operations • Economics a) Cost/benefit analysis b) Cost of development c) Land tenure • Environmental Assessment • Local Land Governing Laws • Farm DesignThe Socio-Economic Environment The socio-economic environment is the overall backdrop the venture willinterdependently operate within. This not only provides the social surroundings whichinfluence the level of local skills and attitudes where interactions occur through employmentand procurement, but also the potential level of integration the project will have with the restof the local community. General local attitudes will reflect the style of life, education, workethic, assumptions, beliefs and values and commonly utilized agricultural practices within thecommunity. This also shapes the types of businesses and farming that are owned and operatedin the local community and the visions they are based upon. These factors influence the skilllevel of potential local workers, willingness to accept new practices and commitment.Likewise, these factors will also influence the type of local fabricators available, their skillsand engineering sophistication and versatility. Identifying characteristics as the size of farms in the area, the diversity of crops, themethods of production and mechanization used, markets for produce produced, supportbusinesses and the rate of overall economic growth and prosperity will help identify the localdrivers of the economy. This will help assess if there is any potential synergies betweenequipment already being used in the area and essential oil production. It also can be assessedhow the new venture will fit socially and economically into the community. This is important
  24. 24. 24 Murray Hunterfrom the point of view of gaining local cooperation and goodwill verses disinterest,skepticism and even non-cooperation. Labour availability is an issue now common to many areas in the Asia-Pacific region.Rural Australia is now developing acute labour shortages in some rural regions [58], relyingon temporary labour from outside the country. Malaysia also has an ageing small holderpopulation base where the younger generation prefers jobs in other sectors [59]. Much of theestate sector now relies upon workers from Thailand, Indonesia, Bangladesh, Nepal andVietnam [60]. Thailand still has plentiful labour in some parts of the country, but as jobs inthe cities pay higher wages such as the construction industry [61], some regional shortagescan occur. Countries like the Philippines, Vietnam, Laos, Cambodia and Indonesia have largelabour pools, but primarily unskilled. Securing a skilled and reliable rural labour force is nowa major challenge facing agro-businesses throughout the whole region and is an issue that cantake an enormous amount of time and effort. Site distance from major towns, cities, ports, railway yards and airports brings up anumber of logistical issues from sourcing specialist parts and materials, to picking uppotential customers for site visits. Inland freight can be as expensive as international freight toany part of the world. Often local logistics are inefficient where drums may lie around yardsfor days before being transported to their feeder destinations for overseas shipping. Likewise,the availability or non-availability of amenities like electricity will determine whether powersupply is just a simple matter of connecting to the local grid or whether an innovative solutionis needed to secure power requirements for the operation. Nearby research institutions and universities can be identified for potential researchsynergies and potential collaboration. Universities can be invaluable for collaborativeresearch and analysis. This form of collaboration is invaluable for any new projectdevelopment. Research institutions and universities have played key research roles inessential oil development in Australia, New Zealand, Thailand and Vietnam.Overall Land Topography-Ecology Site topography-ecology is a key factor in the successful growth of crops andsustainability. Topography, soil and climate are three important extrinsic variables that havegreat influence upon crop growth [62]. Each potential site has its own unique topographywhich will require site specific practices to manage a crop successfully. Each potential cropwill have an optimal environment set that will lend itself for the optimal growth withmaximum yields and quality. As it is rarely possible to find a perfect environment for a crop,‘trade-offs’ and adjustments can be made to site field preparation and crop managementtechniques to optimize site specific results. Potential problems and opportunities must beidentified at site level so that it can be assessed as, a) a potential site to work with, b) amarginal site, or c) a potential site to be avoided. Individual sites will not have uniformconditions, so within the site areas with the best conditions should be identified for initialdevelopment. Each site should be assessed to its suitability to the requirements of the proposed crop(s)and planned infrastructure development. Some of the factors relevant to the issues include;
  25. 25. Enterprise Viability and New Crop Potential 25 a. The suitability of land slopes, effective field size, general field drainage, drainage paths, and potential aversion to flooding. Is there access for tractors and machinery to enter and exit fields? What potential general field design and layout are possible? b. Looking at existing types and vitality of vegetation and crops across the property to gauge some idea about the overall site quality. c. Assess areas where there is direct exposure to strong winds and other weather phenomena that could be potential damage spots. Look at areas where rainfall can cause potential swampy conditions due to poor drainage. d. Examine the temperature and number of daylight hours to assess for potential growth vitality. e. Look at rivers, dams, creeks and streams running through and beside the property, as well as their upstream catchments to assess water supply and what chemicals and wastes will flow into the hydro-system. f. Examine known pests and diseases in the general area so an assessment of potential threats can be made. Also look at what pests proposed crops are susceptible to and if there is any history of herbivore in the area. g. Assess local wildlife and livestock and property accessibility for them to look at potential damage and threat to existing fauna, h. Look at existing road grid, any irrigation system, fencing, buildings and facilities to assess the amount of capital required for building basic infrastructure. i. Look at activities being undertaken on adjoining properties and the history of activity of the proposed land site, and j. Assess the scenic potential of the land if any agro-tourism is planned. Answering the above questions and issues will provide some idea about whether theproposed land site will meet the requirements of the proposed crop. Further assessmentshould be made about the impact and costs of improving conditions and infrastructure, if thesite is selected. a. What land work would be required to develop the site to a level that it would be suitable for planting the proposed crop (i.e., field gradient for run-off rain, drainage run-off to dams, access roads, processing centre for extraction, workshop and storage area for equipment)? Development can be undertaken in stages, so where would field trials, semi-commercial and commercial production take place? b. What would be the actual available field area after taking into consideration marginal land, boundaries, dams, built up areas, natural habitats, etc? c. What effect would the project have on any free roaming fauna at the site? Would it be compatible to the project or become a pest? d. Can any potential pest and diseases be managed effectively? e. Can the operation be run without contamination from upstream catchment areas and adjoining properties? f. What would be the cost to develop the site? Consultation with local users would be wise to get more insight into the above issues. Asite inspection is only a snapshot of a short visit and local information may assist in filling ininformation about seasonal variation in conditions at the site. The appraisal should through
  26. 26. 26 Murray Hunterclimate and topography assessment provide an understanding of what would be the bestnursery propagation, planting and target harvesting seasons and thus how a work schedulewould be implemented on the site. Figure 9.7. is a pictorial representation of the issues toconsider. Essential oil crops were mostly produced in their traditional geographical regions oforigin until after the Second World War. For example, the production of orris root oil (Irispallida and florentina L.) was restricted to Tuscany, as it was believed very specifictopography, soil and climate was required for production [63]. Now orris root is cultivated inaround the rest of Italy, France, Germany, Morocco and India [64]. Similarly lemongrass,citronella, rose and a host of other oils were subject to disruption caused by post colonialpower struggles, wars and political upheavals, rising costs and other factors which forcedproduction to spread to new regions. This change in production geography brought about achange to the generally accepted belief that essential oils should be cultivated in theirtraditional areas for the best qualities. Now it is believed that differing chemical profiles ofessential oils from different regions tend to be more related to differences in geneticcharacteristics than with topography [65]. Daylight hours UV radiation Atmosphere Wind drift Sun Temperature Humidity Rainfall Nitrogen, gasses, etc Climate & Weather Conducive weather, or floods, droughts, etc Farm/Plantation Fertilisers, herbicides, Economic Propagation insecticides Products Some wastes Cultivation recycled Leaf & organic decompositions Processing Runoffs Surface water Insects Wastes and pests Soil Floor Chemical residuals Genetic Sub-Soil Biodiversity Watershed runoffs onto farm/plantation Other Farms Sub-terrainium water Lakes Rivers Regional Eco-System Canals A Farm/Plantation as a System OceansFigure 9.7. Topography-Ecology Issues to Consider in Land Selection.
  27. 27. Enterprise Viability and New Crop Potential 27Altitude The existence of mountainous regions in Papua New Guinea, Indonesia, Malaysia,Thailand, Laos, Vietnam and the Philippines enables a number of micro climaticenvironments where a number of temperate crops are grown. Various altitudes, together withfactors as the slope of the mountain, prevailing winds, cloud cover and precipitation createfurther diversity in altitudinal climates [66]. Different landforms such as rocks, boulders andstones also play a role, as well as fauna interactions, competition between species and humanintervention [67]. With a 1000 feet rise in altitude there is approximately a 1.5° decrease inmean temperature until around 4,500 feet ASL, where the fall in temperature is more rapid[68]. For every rise in 1,000 feet there is a 30.6 mb drop in air density. The effect of reducedO2 and CO2 pressures on plants is still not fully understood [69]. Depending upon distancefrom oceans and latitude, the diurnal variations in temperature can be very wide. Even withsimilar temperature ranges to temperate areas, adaptation can be difficult because of theseextreme diurnal changes, difference in daylight hours [70] and the inability of some plants togo into dominancy because of little seasonal variation in the tropics [71]. Species Richness Herbs Shrubs Trees 1000 Ft. 2000 Ft. 3000 Ft. 4000 Ft. >5000 Ft. AltitudeFigure 9.8. A General Depiction of Flora Species Richness with Altitude. Plant species introduced from temperate climates can adapt to high altitudes by changingmorphologically where it adapts photosynthesis, particularly C4 types [72]. Plants canundergo slow evolutionary adaptation, or undergo ontogenetic modifications which are nonreversible or through acclimatization adjustment. However these adaptations will have aneffect on biomass [73]. These adaptive plants can be called ecotypes [74], which will displayecotypic differences from their parent species [75]. In a study of biodiversity richness with altitude in the Indian Himalayan region,Kharkwal et. al., listed the number of species of each genus of flora according to altitude.Although many other factors like drought inducing factors influence growth at altitudes [76],this study provides a specific spectrum of flora distribution for the Himalayan area [77].
  28. 28. 28 Murray HunterAlthough other mountainous regions will have their own specific spectra of flora distributiondue to localized factors, this study is a good indication of flora distribution with altitude. Thegeneral species richness spectrum according to altitude is hypothetically depicted in Figure9.8.Soil The soil is a dynamic ecological system which provides moisture and nutrients, a mediumto receive waste products and tissue and as a support foundation for plants. Soils also act as afilter for eliminating toxins in groundwater through filtration. Soil is the most criticalingredient in selecting land suitability for a selected crop. Soil develops primarily through the weathering of the surrounding area where parentmaterial is deposited upon the landscape from local rocks, minerals and flora. As mineralsdissolve into the soil, they undergo change and transform through chemical reactions usingsoil moisture as the medium into different materials. This process is aided by the topography,rainfall and climate. The soil contains a number of compounds like oxygen, iron, calcium,potassium and magnesium. Microorganisms form through decaying plant matter andinteraction of plant root systems within the soil layers, in the form of fungi, filamentous andsingle celled bacteria, algae, small animals and insects like worms, snails and ground boringinsects. These organisms play a role in the formation of other organic matter called humus. Humus, along with other minerals plays a role in the colour of the soil, and along withclay controls water retention and the cohesion of the soil. Mineral compounds come indifferent shapes, structures and sizes and form the texture of the soil. The soil structure isformed through the layering and clustering of these materials. Soil is a three phase structure made up of gasses, moisture and solids. The particularcontent mix determines soil ventilation, water intake, storage and drainage capacity. Wheresoil pores are small, the soil will have good water holding capacity, but when pores are large,rapid drainage and evaporation of the soil surface occurs. The surface pores of the soil are themedium where chemicals are absorbed and reactions and decomposition of organic materialstakes place. Through deeper pores nutrients and moisture is diffused through the soil to plantroot systems for uptake. The root system of the plant is the organ through which plants take moisture and nutrientsand release waste products into the soil. Root interaction with the soil also encouragesmicrobial growth within the soil. Plants obtain the elements they need through soil moistureand the soil itself. Through the soil plants obtain nitrogen, phosphorus, sulfur, potassium,calcium, magnesium, iron, manganese, zinc, molybdenum, nickel, boron and chlorine.Through soil water plants obtain carbon, oxygen and hydrogen [78]. Figure 9.9. shows thenutrient take up through the plant root system which provide precursors for the metabolicsystem discussed in chapter 4. Numerous soil classification systems exist throughout the world [79] and are notnecessarily directly comparable. Most soils are a combination of each classification type. Oneexample is the Australian Soil Classification which describes soils under a hierarchy as order,sub-order, great groups, sub-groups and families [80]. Table 9.8. shows a summary of soilsuseful for agriculture at the order level, where sub-orders are distinguished from the mainorders by colour.
  29. 29. Enterprise Viability and New Crop Potential 29 Rainfall (Moisture Source) Soil Surface Organic Materials Water (H2O) Phosphorous (P) Sulfur (S) Carbon (C) Nitrogen fixing bacteria Oxygen (O2) In root system Hydrogen (H) Through air in Nitrogen (N) pores Potassium (K) Iron (Fe) Calcium (Ca) Magnesium (Mg) Mineral Based Materials (Amphibole & Feldspar)Figure 9.9. The Nutrient Take-up Route Through the Plant Root System. Many other names occur for these soils across different regions and classificationsystems, as well as common and informal names by local populations. Another more generalsystem existed before many classification systems were developed and are still in commonuse today [81]. This system provides a useful comparison of soil morphology on the basis oftextural changes and takes three primary forms; • Uniform Soils (U) have little of any textural changes with increasing depth. If the general texture is sand or sandy loam, the profile is classified as Uc (coarse texture). Uniform loam and clay loam profiles are designated by Um (medium texture) and can be sub-divided into non-cracking clays (Uf) and cracking clays (Ug). • Gradational soils (G) become increasingly finer-textured (more clayey) with depth. The major sub-divisions are calcareous soils (Gc) and non-calcareous profiles (Gn). • Duplex soils (D) have clearly defined texture contrasts between the top and sub-soils. They can be sub-divided into red sub-soils (Dr), yellow sub-soils (Dy), brown sub- soils (Db), dark sub-soils (Dd) and greyed sub-soils (Dg).

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