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.

Pigeonpea (Cajanus cajan (L.) Millsp.) is one of the major grain legumes grown in the tropics and subtropics. The crop is grown rainfed in prone drought areas where day length varies from 11 to 14 h and large differences in temperature are experienced, largely due to variations in altitude and latitude. Field studies were conducted with different pigeonpea [Cajanus cajan (L.) Millsp.] in Kenya to determine the effect of photoperiod and temperature on flowering. Variation in temperature was achieved by planting six genotypes at four locations varying in altitude where temperature decreased with increase in altitude and variation in photoperiod was achieved through artificial lighting (about 12.6 hr-natural day length, 14.5 hr and 16.0 hr). The genotypes used in the study were carefully selected to represent different maturity duration (extra-short-, short-, medium-and long maturity duration) and major piegonpea production regions. Equations that describe the rates of development (1/f) were used to determine rates of progress of each genotype towards flowering as influenced by temperature and photoperiod. For photoperiods below 13 hr, rates of progress towards flowering were influenced by temperature in give genotypes (ICPL 90011, ICPL 87091, ICP 7035, ICP 6927 and ICEAP 00040). The optimum temperature for rapid flowering were 24.7 o C for the extra-short-duration genotype, 23.1 o C for the shortduration genotye, 23.8 and 22.2 o C for medium-duration genotypes and 18.3 o C for the long-duration genotypes, 22.2 o C for medium-duration genotypoes and 18.3 o C for the long-duration genotypes which indicated that the area of origin had a strong influence on adaptation. The effects of photoperiod on rates of progress towards flowering were investigated only under sub-optimal temperatures. The extra-short-duration genotype (ICPL 90011) was the least responsive to variation in photoperiod, while the two long duration genotypes (ICEAP 00040 and T-7) were to most sensitive to photoperiod variation with flowering rate reduced by 0.001 d-1 per hour increase in day length.

Landraces of pigeonpea (Cajanus cajan (L.) Millsp.) were collected from farmer's fields in its major cropping areas in Tanzania. Passport data, including descriptors, information on cultural practices and uses were recorded. Pigeonpea intercropping with maize, sorghum and cassava were found to be the dominating cropping systems, with characteristic differences between regions. In the northern part of the country pigeonpea has been developed into a relatively high yielding cash crop. Also in part of the Coastal Zone and Eastern Plain a market, particularly for green pods, have been developed. It is also in these areas near Dar es Salam that pigeonpea is most frequently found as a garden crop.The study showed that farmers mainly relay on self-saved seed, but seed is also quite often provided from other sources. About one third of the farmers selected sowing seed in the field at harvest. Seed storage was considered a great problem, and a variety of indigenous storage techniques were recorded. Chemical seed dressing was only common in the Northern Highlands, where the crop plays an important role as a cash crop. In all areas pigeonpea was consumed green as well as dry. Dry pigeonpea was most often consumed as whole grains, but dehulling was common especially in the Southern Plain. Most landraces identified were long-duration types, medium-duration types only being common in the Coastal Zone. The recorded plant and seed traits varied considerably, but the frequency of landraces with relatively large white or cream seeds and large pods was high in all regions. A number of accessions with potential resistance to fusarium wilt, bruchids and pod borer were identified.

To develop a preliminary screening procedure for waterlogging resistance, a waterlogging resistant ICP 8379 and a waterlogging susceptible cultivar ICP 7035 were grown in pots using different growth media and subjected to 6 days of waterlogging. Waterlogging caused a significant reduction in root dry mass of both cultivars which was greater in ICP 7035 than tn ICP 8379, The reduction in shoot dry mass was comparatively small. The most conspicuous differences between the two cultivars occurred in terms of plant survival. In different soil treatments, ICP S379 showed 0-38 % mortality and ICP 7035 showed 63-100% mortality. The variation in mortality occurred in response to differences in growth medium. Using the growth medium that gave maximum differences, eight additional cultivars were compared along with ICP 7035 and JCP 8379. Significant differences m plant mortality among different cultivars were observed, A number of cultivars showed similar low mortality as ICP 8379, Therefore, there appears to be a potential to use this method for preliminary screening of a large number of pigeonpea cultivars for waterlogging resistance.