Breeding for resistance to extremes of temperature and moisture in cool season food legumes is limited by the lack of adequate screening techniques . The success of each technique depends upon the representativeness and reproducibility of the type of stress created . Descriptions of successful techniques are presented for frost and terminal drought . Development of new screening tests designed to select for specific adaptive traits require a better knowledge of the mechanisms of resistance in these crops, especially to drought . Rooting depth, early vigor, reduced branching, and osmotic adjustment are discussed . Other mechanisms of resistance to drought, heat, freezing, or chilling have been proposed but need to be studied jointly by crop physiologists and plant breeders .

S U M M A R YInadequate soil moisture is one of the main constraints on the productivity of chickpea in the rainfed farming systems of the dry areas in West Asia and North Africa. The response to irrigation at flowering and pod filling of winter-and spring-sown kabuli chickpea was studied in 1983-86 at ICARDA's main research station at Tel Hadya in northern Syria. In 1983/84 when the cultivar ILC3279 was sown in winter, irrigation increased yield by 105% over a crop receiving 229 mm of precipitation. In 1984/85, ILC3279 was sown in winter and spring. Advancing the date of sowing to winter increased yield by 65% and irrigation increased seed yield by 73% in winter and 143% in spring sowings compared with crops grown receiving 373 mm rainfall.In 1985/86, six cultivars (ILC482, ILC3279, FLIP81-57W, FLIP81-293C, FLIP84-19C and FLIP84-80C) were compared, but differences in their response to irrigation were negligible. Advancing sowing from spring to winter increased seed yield by an average of 66%. Irrigation increased seed yield in winter and spring sowings by 56% and 72%, respectively, over those receiving 316 mm annual precipitation. Irrigation is, therefore, a way of increasing the productivity and yield stability of chickpea in northern Syria but the improvement in yield depends on the total rainfall and its distribution over the growing season.

Rising food and nutritional insecurity threatens the livelihoods of millions of poor people, particularly in sub‐Saharan Africa. Vegetable and legume production and consumption are a potent mechanism for small‐scale, disadvantaged farmers to obtain the required nutrients in their diets and to generate much‐needed income through trade. Vegetables and legumes are key sources of nutrients and health‐promoting phytochemicals, providing higher micronutrient contents and a wider spectrum of essential compounds to meet nutritional and health needs than other food sources. Diversifying diets with vegetables and legumes is a cheaper, surer, and more sustainable way to supply a range of nutrients to the body and combat malnutrition and associated health problems than other approaches that target only a single or a few nutritional factors. Furthermore, vegetables and legumes often accompany staple crops in meals, and most staple crops are less palatable without vegetable or legume accompaniments. As a growing world population demands more and higher quality foods, and as environmental problems such as soil degradation, water scarcity, biodiversity loss, and climate change become more acute, the need for innovative vegetable and legume research solutions to improve food and nutritional security cannot be overemphasized.

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Improved varieties of legumes adapted to nutrient deficiency have the potential to improve food security for the poorest farmers. Tolerant varieties could be an inexpensive and biologically smart technology that improves soils while minimizing fertilizer costs. Yet other technologies that improve productivity and appear to be biologically sound have been rejected by farmers. To translate benefits to smallholder farmers, research on low-nutrient tolerant genes and crop improvement must keep farmer preferences and belief systems in the forefront. We review farmer participatory research on legume-intensification and soil fertility management options for smallholder farmers in Africa, including recent results from our work in Malawi and Kenya. We suggest that indeterminate, longduration legumes are the best bet for producing high quality residues, compared to short-duration and determinate genotypes. This may be due to a long period of time to biologically fix nitrogen, acquire nutrients, photosynthesize and grain fill. Also, the indeterminate nature of long-duration varieties facilitates recovery from intermittent stresses such as drought or pest pressure. However, indeterminate growth habit is also associated with late maturity, moderate yield potential and high labour demand. These traits are not necessarily compatible with smallholder criteria for acceptable varieties. Malawi women farmers, for example, prioritized early maturity and low-labour requirement, as well as yield potential. To address complex farmer requirements, we suggest the purposeful combination of species with different growth habits; e.g. deep-rooted indeterminate long-duration pigeonpea interplanted with short-duration soyabean and groudnut varieties. On-farm trials in Malawi indicate that calorie production can be increased by 30% through pigeonpea-intensified systems. Farmers consistently indicate strong interest in these systems. In Kenya, a 55% yield increase was observed for a doubled-up pigeonpea system (a double row of pigeonpea intercropped with three maize rows) compared to traditional, low density intercrops. However, the need for improved pigeonpea varieties with high intercrop suitability, including reduced early branching, was highlighted by a farmer preference study in the same area. These examples illustrate the potential for participatory research methodologies to drive biophysical research in farmer-acceptable directions.