Simon Mng'omba

World Agroforestry Centre (ICRAF), Lilongwe8th November 2016Chitedze, Lilongwe

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

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

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)

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 perunit of landEmployment opportunities • rural & urban areas: more consumption of vegetables/fruits creates

a marketMind 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

Vegetable production: A case in MalawiCultivation 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

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 – 200318 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).

Crops grown in wetlands

Crop type HHs who cultivated (%) *

All

Male FemaleVegetables 56 42 52Maize 53 38 49Rice 21 9 17S. potato 10 11 10Beans 9 7 8Cassava 6 0 4Others 14 16 15

Source: Tracy et al. 2009

• *Multiple responses• Dominance of vegetables

Solutions suggested Respondents (%) *

Plant trees along river banks 74

Avoid cultivating crops along river banks 25Avoid cutting trees/reeds along river bank 18Close barrages

11Promote irrigation

11

Why are farmers still cultivating fragile lands?agriculture accounts for > 80 % of employment

Knowledge, practices & challenges in the SRB

TechnologyHouseholds (%) 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 6pest & diseases; lack of seed & training

woodlot 86 31 2lack of seed & training, small land area

soil/water conservation 85 70 0

lack of information & training

farmyard manure & compost

89 47 0lack of training & too much labour

Source: Ajayi et al. 2010

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)

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

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

Evidence of improved yield due to biomass application

Treatment Fruit yield (mg/ 9 m2) 2007

Fruit yield (mg/ 9m2) 2008

Control 89.7 202.2Inorganic fertilizer 97.4 221.7Gliricidia (8 t/ha) 124.7 289.7Gliricidia + 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

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 15.54Gliricidia (8 t DM/ha) 16.5 – 33.95 25.62Tephrosia (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 9.57Gliricidia (8 t DM/ha) 6.86 – 15.76 11.04Tephrosia (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)

Evidence for increased production and quality

Production under

Marketable /40 m2

Number KgNon-market./40 m2

Number KgTotal yield (t/ha)

Protected 10,769 401 79 1.9 100.79Open 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

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

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 bitt er 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

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

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

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

THANK YOU !!!