Managing Ecosystems using Low-cost Protected Cultivation with Agroforestry Leaf Biomass Transfer: Fruit and Vegetable Production in Malawi

1. Simon Mng'omba
World Agroforestry Centre (ICRAF), Lilongwe
8th November 2016
Chitedze, Lilongwe
Managing Ecosystems using Low-cost Protected
Cultivation with Agroforestry Leaf Biomass Transfer:
Fruit and Vegetable Production in Malawi

2. PRESENTATION OUTLINE
Introduction
• global fruit & vegetable production
• open vs protected cultivation
• negative impacts of open cultivation
Production technologies
• Keyhole gardens
• Hydroponics
Evidence of fertiliser tree biomass on fruit yield
• Effect of organic fertilizer on paprika yield
• Protected cutivation of tomato yield
Conclusions

3. World Fruit and Vegetable Production
Fruit production
• 640 million tons of fruits produced in 2011
• High increases have been tropical fruits (e.g. banana, mango etc. )
Vegetable production
• 1.811 billion tons of vegetables (2009)
Production
• fruit & vegetable production: >2.4 billion tons (FAO, 2009)
• Global export trade exceeds US$ 17 billion annually*
• Subsistence micro-gardens (villages) to huge commercial
enterprises (greenhouses & field crops/orchard)
• Involves application of fertilizer, water, pesticides etc.
FAOSTAT, 2009; *Scripta Horticulturae 14 (2012)

4. Benefits of Fruits and Vegetables
Food, Nutrition and Health
• rich in micronutrients, vitamins, water etc. (about 1.7 million deaths
worldwide are due to low fruit & vegetable consumption)
Income generation
Vegetables/fruits have high returns per
unit of land
Employment opportunities
• rural & urban areas: more consumption of vegetables/fruits creates
a market
Mind provoking thoughts (Scripta Horticulturae No. 14)
• Production shift: from countries with high energy inputs and labour costs to those
with lower energy and labour costs (tropical countries, southern Africa???)
• Population growth by 2045 is estimated at 9 billion hence increase in fruit &
vegetables to 3.1 billion tons. Where will this increased production come from?
source: www.fao.org/giews/english/fo/index.htm

5. Vegetable production: A case in Malawi
Cultivation is on open field & fragile
lands e.g.
• riverbanks
• wetlands (damboland)
• water catchment areas
• flood plains (fertile soils &water)
>80% of total vegetable
production is by smallholder
farmers in rural /peri-urban
areas (Mwandira 2003)
Ecosystems heavily disturbed
• high soil erosion: siltation
• floods rampart
• water shortage
• water body pollution due to
• pesticide residues
• fertilizer drift
• high weed growth
consequently, in Malawi
By Simon Mng’omba
By Chris Katema

6. Effects of unsustainable land cultivation
By Simon Mng’omba
Total cost of :
• weed management at Liwonde Barrage:
US$ 366,328.57 per year (revenue lost)
• Remedial costs (dredging & diving) incurred
by ESCOM (Nkula, Tedzani & Kapichira
power stations) is about US$ 959, 615
each year
Source: UNDP, PIMS 2085, (2010) PPP in SLM in the SRB in Malawi; GoM 2014
Between 1967 – 2003
18 floods occurred in Malawi affecting 1.8 million people resulting in:
• loss of life
• infrastructure destruction (roads, rail, homes etc.)
• crop loss and food insecurity
• health impacts (diarrhoea, cholera and malaria).

7. Crops grown in wetlands
Crop type HHs who
cultivated
(%) *
All
Male Female
Vegetables 56 42 52
Maize 53 38 49
Rice 21 9 17
S. potato 10 11 10
Beans 9 7 8
Cassava 6 0 4
Others 14 16 15
Source: Tracy et al. 2009
• *Multiple responses
• Dominance of vegetables
Solutions suggested
Respondent
s (%) *
Plant trees along river
banks 74
Avoid cultivating crops
along river banks 25
Avoid cutting trees/reeds
along river bank 18
Close barrages
11
Promote irrigation
11
Why are farmers still cultivating fragile lands?
agriculture accounts for > 80 % of employment

8. Knowledge, practices & challenges in the SRB
Technology
Households (%) who Constraints using
the technologyKnows the
technology
Currently use
the technology
Used it before
but stopped
Inorganic
fertilizer
100 73 11 no extension services
fertilizer trees 72 15 6 lack of seed & training
fruit trees 95 71 6
pest & diseases; lack of
seed & training
woodlot 86 31 2
lack of seed & training,
small land area
soil/water
conservation
85 70 0
lack of information &
training
farmyard
manure &
compost
89 47 0
lack of training & too
much labour
Source: Ajayi et al. 2010

9. Unsustainable cultivation in the Shire River Basin
Investing in enterprises (e.g. bee-keeping,
juice & livestock production, tree planting &
agroforestry technologies) can
• provide incentives to adoptions of
SLM approaches (soil & water
conservation) as IGAs
• discourage growing vegetables
along the river banks for income
• investing in juice making & AF
means many trees will be planted
and hence protecting soil loss
Source: GoM, Ministry of Water Development & Irrigation (2011)

10. Production methods with limited Ecosystem disturbance
1. Protected cultivation - uses structures such as:
- shade houses
- row covers
- net tunnels
- plastic tunnels (plasticulture)
2. Micro-gardens – e.g.
- sack farms (recycled sacks)
3. Key hole gardens
4. Hydroponics - gardening without soil & uses 70-90% less water.
Aeroponics are a form of hydroponic
by Simon Mng’omba

12. Low-cost protected cultivation structures
Bamboo & plastic
Plastic rolled up & down
Ideal for:-
• smallholder farmers- simple & affordable
• hotspot areas (protection) e.g. flood plains
• profitable
• low water utilization
• high quality vegetables produced
• no blemishes due to limited pest &
disease attack hence higher prices
Low-cost protected cultivation structures:-
• an alternative & sustainable fruit &
vegetable production
• Fertilizer tree biomass incorporation
improves crop yield

13. Evidence of improved yield due to biomass application
Treatment Fruit yield (mg/ 9 m2)
2007
Fruit yield (mg/ 9m2)
2008
Control 89.7 202.2
Inorganic fertilizer 97.4 221.7
Gliricidia (8 t/ha) 124.7 289.7
Gliricidia + fertilizer 96.3 372.1
Source: Sileshi et al. 2007
Recommendations:
• Gliricidia biomass integrated with half recommended dose of
inorganic fertilizer improved paprika fruit yield
• Gliricidia biomass alone also improved paprika fruit yield
Table 1: Effect of organic/inorganic fertilizer on Paprika fruit yield

14. Table 2: cabbage yield kg/ha (with inorganic fertilizer: 0, 75 & 150 CAN kg/ha)
Treatment Yield range (kg/ha) Mean yield (kg/ha)
Control 9.02 – 21.96 15.54
Gliricidia (8 t DM/ha) 16.5 – 33.95 25.62
Tephrosia (6 t DM/ha) 21.62 – 35.7 28.94
Source: Makumba and Phiri, 2008
Conclusions:
• Application of AF leaf biomass improved yield
• AF leaf biomass integrated with half recommended dose of
inorganic fertilizer improved yield
Treatment Yield range (kg/ha) Mean yield (kg/ha)
Control 5.25 – 13.87 9.57
Gliricidia (8 t DM/ha) 6.86 – 15.76 11.04
Tephrosia (6 t DM/ha) 9.82 – 17.87 13.81
Table 3: tomato yield t/ha (with inorganic fertilizer: 0, 75 & 150 CAN kg/ha)

15. Evidence for increased production and quality
Production
under
Marketable /40 m2
Number Kg
Non-market./40 m2
Number Kg
Total yield
(t/ha)
Protected 10,769 401 79 1.9 100.79
Open field 4,145 133 371 6.8 34.88
Conclusions
• Higher yields from low-cost protected structures than from open
field
• Higher quality fruit & vegetables low-cost protected structures than
from open field
Table 4: tomato yield under open & protected structure
Source: Gonzaga et al. 2012

16. Protected cultivation structures
• High-cost - permanent structures such as greenhouse / glasshouse
covered with UV treated plastic. Can be house type: ideal for
tall/climbing vegetables (melons)
• Low-cost structures
e.g. low tunnels:
Low tunnel covered (top) & uncovered (bottom)
Source: Gonzaga et al. 2012

17. Benefits of Protected Cultivation
• Vegetables & fruits mature faster (30%) than field-grown crops
• Carrots – when grown under greenhouse they are sweeter & tender
than grown outdoors (phenols)
• Cucumbers - when grown under greenhouse they are less bitter
than when grown outdoors (phenols)
• Better pest & disease management - reduces pesticide usage
• Reduction in water use: plastic sheets reduce evapotranspiration
• All year-round production & predictable yields and quality
Source: Gonzaga et al. 2012; Mangmang 2002

18. Why low-cost protected cultivation structure?
• low investments in structures
• easy construction (local artisans can construct)
• materials are available
• simple maintenance
• crop yields are not different from high cost-protected cultivation
Selection protected cultivation structure
depends on:
• crops to be grown (a g/house may not be
needed)
• A simple structure can economically
extend growing season. E.g. low tunnels

19. Low-cost protected cultivation with biomass transfer
We need
• Expertise in protected cultivation (to train artisans)
• Focus on Hotspot areas (flood plains, river banks, wetland etc.) need to:
• assess level of horticultural crop production
• assess impact on environment (soil erosion)
• assess market for vegetables considering different seasons
• Design of protected cultivation structures consider:
• site (hot areas may require rolling up sheet)
• crop management under g/house conditions
Low-cost protected cultivation structures and AF leaf biomass
transfer have a great potential to sustainably produce fruits and
vegetables in hotspot areas

20. Conclusions
Low-cost protected cultivation with AF tree biomass transfer can:
• Improve income levels – poverty reduction
• Reduced heavy fertilizer & pesticide application
• Protect ecosystems
• High crop yield and good quality crop
• Increase urban supply of high quality fresh produce
• All year round supply
• Enables early production

21. THANK YOU !!!