This document summarizes a credit seminar given by Zahid Abass Wazir on ecological engineering as a new direction for agricultural pest management. The seminar discusses ecological engineering as a habitat manipulation technique that focuses on reducing mortality of natural enemies to provide resources like nectar and pollen. It presents the advisory committee for Wazir's PhD, then introduces ecological engineering and its advantages over chemical pesticides. Mechanisms of top-down and bottom-up control are described, as well as ways to enhance natural diversity and design pest-stable agroecosystems through practices like increasing species and genetic diversity. Case studies demonstrating habitat manipulation techniques are also summarized.

1. CREDIT SEMINAR
TOPIC :
Ecological Engineering, a new
direction for agricultural pest
management
Name : Zahid Abass Wazir
Regd. No.: J-18-D-331-A
(PhD Scholar)

2. ADVISORY COMMITTEE
1. Dr. Uma Shankar (Major advisor)
Associate Professor, Division of Entomology.
2. Dr. Amit Kumar Singh (Member from Major subject)
Associate Professor, Division of Entomology.
3. Dr. Ranbir Singh (Member from Minor subject)
Associate Professor,Division of Plant Pathology.
4. Dr. Satesh Kumar (Member from Supporting subject)
Associate Professor,Division of Veg. science & Floriculture.
5. Dr. Sachin Gupta (Dean Nominee)
Associate Professor, Division of Plant Pathology

3. INTRODUCTION
 Agriculture pests are one of the major threats in the declining of global
agricultural food grain production that led to food security.
 Annual yield loss due to insect pests in major crops : 18 percent in the
absence of control measures (Oerke,2006).
 Application of chemical pesticides to control agricultural pests has been
effective but at same time led to several problems like pest resurgence, pest
outbreak , environmental pollution , human and animal health hazards,
killing of non target organism or beneficial organism.
 Ecological engineering is one latest emerging tool which can be used to
redress the problems of insect pest and management of agricultural pests.
 Ecological engineering is also referred to as Habitat manipulation which
focuses on reducing mortality of natural enemies .

4. What is Ecological Engineering ?
• Term was first coined by Odum (1962).
• Use of cultural techniques to effect habitat
manipulation and enhance biological control is the
philosophy of ecological engineering. (Gurr et al 2004).
• Ecological engineering refers to manipulation of habitat
that focuses on reducing mortality of natural enemies,
providing the supplementary resources and
manipulating host plant attributes for the benefit of
natural bio-agents.
• It aims to provide the natural enemies of pests with
resources such as nectar (Baggen and Gurr 1998),
pollen (Hickmen and Wratten 1996), physical refugia
(Halaji et al. 2000) alternative hosts (Viggiani 2003) .

5. Characteristic Ecological Engineering
Units engineered
Tools for engineering
Principles
Biotic diversity
Maintenance and
development costs
Public acceptability
Level of current use in
agriculture
Species
Ecosystems
Ecology
Maintained/enhanced
Moderate
High
Limited uptake in developed
countries, though reflected in
many traditional agricultural
systems.

6. Advantages of Ecological Engineering:
1. Reduces the dependance on chemical pesticides.
2. Makes cultivation profitable by reducing cost of
production.
3. Reduce environmental and health hazards.
4. Effective management of target pests.
5. Conservation of natural enemies and beneficial
organism.
6. Maintenance of biodiversity.

7. MECHANISMS
Habitat manipulation approaches :
1. Top down control
Here herbivores (second trophic level) are suppressed by the
natural bio-agents (third trophic level) and this type of approach is
seen in ‘Augmentive biological control’.
2. Bottom up control
In this approach, manipulation within crop, such as green
mulches and cover crop (first trophic level) will act on pests directly.
This type of approach is seen in habitat manipulation of ‘Conservation
biological control’.

9. Ways to enhance natural diversity
1. Structural and cultural diversity
 Trees and other tall vegetation can provide the vertical structure needed by spiders and
birds.
 Flowering shrubs, herbs and annual and perennial forbs can provide for parasitic
ichneumonids and syrphids that feed on flower, nectar and pollen.
2. Overwintering sites
 Windbreaks can be used by arthropod predators as overwintering sites if appropriate
vegetation is available.
 In South Carolina, certain species of coccinellids that feed on insect pests of field and
orchard crops overwinter at field edges in herbaceous vegetation, grass, and tree litter
(Roach and Thomas, 1991).
 Woody field edges can provide habitat for birds or small mammals that feed on insect
pests during the winter (Black et al., 1970; Johnson and Beck, 1988).

10. 3. Cultural Practices
 Cultural practices can radically alter the abundance of predators such as
spiders, birds, and small mammals.
 Clean cultivation of a field or around trees may increase crop survival but also
can decrease survival of birds, small mammals, spiders, or carabids that use the
vegetation for shelter.
For example, crop stubble left in fields might contain overwintering parasitic
wasps or may provide cover for predators such as birds, overwintering spiders,
or beetles.
4. Windbreak design
 It is another method of manipulating natural enemy abundance, and diversity.
 In North Dakota, carabids and staphylinids (Coleoptera) that feed on crop pests were
more abundant at the edge of multi-row wind breaks than in the interior of the
windbreak (Katayama, 1980).
 Insectivorous birds establish large territories and prefer larger, wider windbreaks
5. Pesticides
 Minimizing the use of pesticides.
 proper selection and application of pesticides on need based.

12. Designing pest-stable agroecosystems
Key agroecological guidelines for restoring agricultural
diversity:
 increase species diversity in time and space
through multiple cropping and agroforestry designs.
 increase genetic diversity through variety
mixtures,multi-lines and use of local germplasm.
 include and improve fallow through legume-based
rotations, use of green manures, cover crops and/or
livestock integration.
 enhance landscape diversity with biological
corridors and vegetationally diverse cropfield.

13. Ecological Engineering for pest management-Below Ground
• Crop rotation with leguminous plants which enhance nitrogen
content
• Keep soils covered year round with living vegetation or crop
residue
• Add organic matter in the form of FYM, vermicompost, crop
residue which enhance below ground biodiversity of beneficial
microbes and insects.
• Application of biofertilizers with special focus on mycorrhiza
and Plant growth promoting rhizobia (PGPR)
• Application of balanced dose of nutrients using biofertilizer
based on soil test report

14. Ecological Engineering for pest management-Above Ground
The main aim is to increase natural enemy diversity above ground which contributes
significantly to the management of insect pests both below and above.
To attract natural enemies following activities should be practised :
• Raise flowering plants/ compatible cash crops along the field border by arranging
shorter plants towards main crop and taller plants towards the border to attract natural
enemies as well as to avoid immigrating pest population
• Grow flowering plants on internal bunds inside the field
• Don’t uproot weed plants those growing naturally such as Ageratum sp which act as
nectar source for natural enemies
• Don’t apply broad spectrum chemical pesticides.
• Reduce tillage intensity so that hibernating natural enemies can be saved
• Select and plant appropriate companion plants which could be trap crops and pest
repellent crops.

15. Mustard Chrysanthemum spp.
Alfalfa
Buckwheat
Sunflower
Carrot
Plants Suitable for Ecological Engineering for Pest Management
Attractant plants

16. Crotalaria spp.
Berseem clover
Coriander
Repellant plants
Ocimum sp Spearmint

17. Trap plants
Marigold Castor
Border plants
Ryegrass Bajra
Barrier/guard plants
Maize Sorghum
Note : selection of flowering plants is be based on availability, agro-
climatic conditions and soil types

18. Agroforestry’s role on the ecology
and management of insect pest populations
Agroforestry ?
 It is an intensive land-management system that
combines trees and/or shrubs with crops and/or
livestock on a landscape level to achieve optimum
benefits from biological interactions.
 Few reviews on pest management in agroforestry
showed that the high plant diversity associated with
agroforestry systems provide some level of protection
from pest and disease outbreaks. (Rao et al. 2000;
Schroth et al. 2000)

19. Effects of trees in agroforestry on insect pests and
associated natural enemies :
1. Shade effects
 Shade from trees help to reduce pest density in understorey
intercrops.
 Hedgerows or windbreaks of trees have a dramatic influence on
microclimate.
 Tall intercrops or thick groundcovers can also alter the
reflectivity, temperature and evapotranspiration of shaded plants
or at the soil surface, which in turn could affect insects that
colonise according to ‘background’ colour or that are adapted to
specific microclimatological ranges (Cromartie 1991).
Examples :
• In coffee, the leafminer(Leucoptera meyricki) is reduced by shade,
whereas the coffee berry borer (Hypothenemus hampei) may increase
under shade.

20. 2. Alternate Host
 Trees can also provide alternate hosts to natural enemies.
Example : planting of prune trees adjacent to grape vineyards to support
overwintering populations of the parasitoid Anagrus epos (Murphy et al. 1996).
3. Nutritional and cover effects
 A number of entomological studies conducted indicate that plantations with rich
floral undergrowth exhibit a significantly lower incidence of insect pests than clean
cultivated orchards, mainly because of an increased abundance and efficiency of
predators and parasitoids, or other effects related to habitat changes.
 In the Solomon Islands, O’Connor (1950) recommended the use of a cover crop in
coconut groves to improve the biological control of coreid pests by the ant
Oecophylla smaragdina subnitida.
 Wood (1971) reported that in Malaysian oil palm (Elaeis guineensis) plantations,
heavy groundcover, irrespective of type, reduced damage to young trees caused by
rhinoceros beetle (Oryctes rhinoceros).

21. 4. Plant diversity and natural enemies
 Agroforestry holds a great promise for increasing insect diversity and reducing pest
problems because the combination of trees and crops provides greater niche diversity and
complexity in both time and space than does polyculture of annual crops. (Stamps and
Linit ,1997).
Examples :
• Maize associated with hedgerows experienced significantly lower stalk borer (Busseola
fusca and Chilo spp.) and aphid (Rhophalosiphum maidis) infestations than did pure maize,
the margin of difference being 13% and 11% respectively for the two pests.
• In one of the studies, Peng et al. (1993) confirmed the increase in insect diversity and
improved natural enemy abundance in an alley-cropping system over that of a monoculture-
crop system.

22. Entomophage Parks.
• Entomophage parks : Plays imp role in ecological engineering.
• Entomophage parks can be defined as areas free of pesticide
applications set aside for the purpose of protecting populations of
natural enemies. Such areas can be of immense utility in conserving
and improving natural enemy fitness in areas intensively dominated
by agriculture.
• provide them with resources such as nectar, pollen, physical
refuge, alternative prey, alternative hosts and mating sites.

23. Entomophage park Case at Skuast jammu in 2007 :
Outcome :
1. Both entomophage diversity and abundance in the park were much
higher than in the adjacent agricultural fields of vegetables and cereals.
2. A total of 61 species of natural enemies were recovered from the
entomophage park, as compared to 22 and 20 species in cereal and
vegetable fields, respectively.
3. The abundance of parasitoids (ichneumonids, braconids, scelionids and
chalcidoids) was significantly higher in the park as compared to
surveyed agricultural fields, as was egg parasitism by scelionids
(Telenomus spp.) and trichogrammatids, and parasitisation by the larval
parasitoid Campoletis chlorideae on Helicoverpa armigera.
( Gupta et el. 2012)

24. Practical case studies of Habitat
Manipulation / Ecological
engineering :
1. Flowering plants(Phacelia tanacetifolia )strips have been used in
wheat, sugar beets and cabbage, leading to greater abundance of
aphidophagous predators (especially syrphid flies) which resulted in
reduced aphid populations.
2. In England, to provide suitable overwintering habitat within fields
for aphid predators, researchers created ‘beetle banks’ sown with
perennial grasses such as Dactylis glomerata and Holcus
lanatus.When these banks run parallel with the crop rows, great
enhancement of predators (up to 1500 beetles per square metre) can be
achieved in only two years (Landis et al. 2000).

25. 3. Organic farmers maintained floral diversity throughout the growing
season in California vineyards, in the form of summer cover crops of
buckwheat (Fagopyrum esculentum) and sunflower (Helianthus
annus). During two consecutive years, vineyard systems with
flowering cover crops were characterised by lower densities of
leafhoppers and thrips, and larger populations and more species
of general predators, including spiders. (Nicholls et al. 2001).
4. In a two-year study, researchers found higher parasitism of Ostrinia
nubilalis larvae by the parasitoid Eriborus terebrans in edges of maize
fields adjacent to wooded areas, than in field interiors. The study
shows that the abundance and diversity of natural enemies is more on
field exteriors. (Marino and Landis 1996).

26. Examples of ecological engineering for pest management
(a) buckwheat strip in the margin of an Australian
potato crop providing nectar to the potato moth
parasitoid, Copidosoma koehleri (Hymenoptera:
Encyrtidae) (Photograph: G.M. Gurr)
(b) ‘beetle bank’ in British arable field providing shelter to
predators of cereal pests (Photograph: G.M. Gurr)
(c) strip cutting of a lucerne hay stand in Australia
provides shelter to within-field community of
natural enemies (Photograph: Z. Hossain)
(d) New Zealand vineyard with buckwheat ground cover for
enhancement of leaf roller parasitoids (Photograph: Connie
Schratz).

27. FUTURE REMARK
• Undoubtedly , there is broad potential for the application of
Ecological engineering in pest control, mainly if combined
into IPM strategies.
• Dependace on chemical pesticides could be lower and thus
reduce production cost.
• There is need to strengthen the research on defining the role
of the tritrophic interactions and other practices in
improving the efficiency of the natural enemies.
• A concerted research effort between different disciplines
such as Plant Breeders, Agronomist, Soil Scientists, and
Entomologists is necessary to develop viable technologies
with consideration to the conserving of the natural enemies.

28. CONCLUSION
• Ecological engineering is a potential eco friendly
tool for effective management of insect pests.
• It involves human activity that modifies the
environment according to ecological principles and
accordingly manipulates habitat for pest
management .
• A better and comprehensive understanding of
ecological principles is needed that would allow the
researchers to work effectively and efficiently in this
field and manage various insect-pests and diseases
of crop plants.

29. THANKYOU