Sustainable diets and biodiversity

followed green revolution strategies, subsequent

adoption of IPM approaches coupled with the re-

moval of insecticide subsidies, reduced insecticide

use nationally by 50–75 percent, while rice produc-

tion continued to increase annually. The ecosystem

service delivered by natural predation replaced most

chemical control, allowing other inputs and adap-

tive ecosystem management by farmers to secure

and increase rice yields.

Reduced insecticide use in rice

Most tropical rice crops require no insecticide

use under intensification (May, 1994). Yields have

increased from 3 tonnes per ha to 6 tonnes through

the use of improved varieties, fertilizer and irrigation.

Indonesia drastically reduced spending on pesticides

in rice production between 1988 and 2005 [Gallagher

et al., 2005]. However, in the past five years, the

availability of low-cost pesticides, and shrinking

support for farmers’ education and field-based eco-

logical research, have led to renewed high levels of

use of pesticides with consequent large-scale pest

outbreaks, particularly in Southeast Asia (Catindig

et al., 2009; FAO, 2011).

4.2.5 Water management

There are efficiency and productivity gains in crop

water use that can be captured both “within” and

“outside” the crop water system. For example, agri-

cultural practice that reduces the soil evaporation

reduces non-productive water consumption. In

cropping systems adapted to seasonal or low

evaporative demand of the atmosphere, it may be

other types of agricultural practice (fertilizer,

improved varieties, weed and pest management)

that result in more productive consumption of water

available in the root zone.

Deficit irrigation for high yield and maximum net

profits

One way of improving water productivity is deficit

irrigation, whereby water supply is less than full

requirements and mild stress is allowed during

specific growth stages that are less sensitive to

moisture deficiency. The expectation is that any

yield reduction will be limited and additional benefits

are gained through diverting the saved water to

irrigate other crops.

A six-year study of winter wheat production on the

North China Plain showed water savings of 2 5 percent

or more through application of deficit irrigation at

various growth stages. In normal years, two irrigations

of 60 mm (instead of the usual four) were enough to

achieve acceptably high yields and maximize net

profits. In studies carried out in India on irrigated

groundnuts, production and water productivity were

increased by imposing transient soil moisture-deficit

stress during the vegetative phase, 20 to 45 days

after sowing. Water stress applied during the vege-

tative growth phase may have had a favourable effect

on root growth, contributing to more effective water

use from deeper soil horizons. However, use of

deficit irrigation requires a clear understanding of

the soil-water (and salt) budgeting and an intimate

knowledge of crop behaviour, as crop response to

water stress varies considerably (FAO, 2002; FAO,

2011 ).

5. Enabling environment and policy framework
   In preparing programmes, policy-makers need
   to consider issues that affect both SCPI and the
   development of the agricultural sector as a whole.
   National policies that seek to achieve economies of
   scale through value chain development and consol-
   idation of land holdings may inadvertently exclude
   smallholders from the process, or reduce their
   access to productive resources. Improving transport
   infrastructure will facilitate farmers’ access to
   supplies of fertilizer and seed, both critical for SCPI,
   and to markets. Given the high rate of losses in the
   food chain – in the order of 30 percent in both
   developing and developed countries – investment in
   processing, storage and cold chain facilities will en-

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