Water use in bean and cowpea: efficiency or effective use of water?

Water stress is one of the major abiotic stress limitations for grain legume production in smallholder agricultural systems. Phenotypic characterization of water consumption by different species of legumes and genotypes within them plays a key role in adaptation to drought. Dynamics of water use may differ depending on the origin and evolution of the species of legume and the agro-climatic conditions faced by the legumes. The supply of nitrogen from symbiotic fixation is also critical for filling seeds and is even more limiting than water in bean, but not in cowpea

Heat tolerance in common bean derived from interspecific crosses

Many Countries could experience unprecedented heat stress because of global climate change (Battisti and Naylor,2009). Heat sensitivity in common bean is a major limiting factor that can reduce yield, quality, and lead to restricted geographic adaptation (Beebeetal.,2011). Interspecific lines developed with crosses between P.vulgaris and P. acutifolius were evaluated for their tolerance to heat stress. Results from field and greenhouse evaluation confirmed that Phaseolus acutifolius is an important and useful genetic resource for improving heat tolerance in common bean. Results from genomic analysis indicated the introgression of P. acutifolious genes into interspecific INB line that was used as apparent for developing heat tolerant SEF lines

Phenotypic evaluation and QTL analysis of yield and symbiotic nitrogen fixation in a common bean population grown with two levels of phosphorus supply

Peer Revie

Quality characteristics of snap beans in the developing world

Pod quality requirements in snap beans vary from region to region. Characteristics related to pod shape, length, color and fiber content, among others, determine the degree to which snap beans are accepted by consumers and processors. The snap bean program at CIAT screens accessions from the germplasm collection and breeding lines for these characteristics, as well as adaptation and disease susceptibility. Information about the quality requirements of some Latin American countries is provided. Research on environmental and agronomic factors affecting snap bean pod quality is also discussed. (AS

Inheritance of temperature sensitivity of the photoperiod response in common bean (Phaseolus vulgaris L.)

Photoperiod response of flowering in common bean (Phaseolus vulgaris L.) is thought to be controlled by the genes Ppd and Hr. However, cultivars also vary in the degree that cooler temperatures reduces their sensitivity to photoperiod. To examine the inheritance of this temperature sensitivity, crosses of cvs. Gordo x de Celaya and Flor de Mayo × Rojo 70 were evaluated at two sites differing in mean temperature and using 12.5-h natural photoperiod or 18-h artificially extended photoperiod. Under 18-h photoperiod at the warmer site, Palmira, no plants of the parents or of the F2 populations flowered, confirming that the parents were sensitive to photoperiod. Under 12.5-h photoperiod at the cooler site, Popayan, the parents for each cross flowered at similar dates and no segregation for days to flower was observed. However, under 18-h photoperiod, de Celaya and Rojo 70 and the F1 populations did not flower within 100 days after planting, while the F2 and F3 populations showed segregation that was consistent with single gene inheritance, late flowering being dominant. Late flowering at Popayan under 18-h photoperiod indicates a lack of temperature sensitivity, so temperature insensitivity of the photoperiod response was dominant to sensitivity. The name Tip, for “temperature insensitivity of photoperiod response”, is proposed for this gene, with the recessive form of this gene conditioning earlier flowering at cooler temperatures with long daylengths. It is recognized that the observed segregation patterns could represent the effect of multiple alleles at the Ppd or Hr loci, and studies are proposed to test this possibility with molecular markers and recombinant inbred lines