Exploiting genomic resources for efficient conservation and utilization of chickpea, groundnut, and pigeonpea collections for crop improvement

Both chickpea and pigeonpea are important dietary source of protein, while groundnut is one of the major oil crops. Globally, ~1.1 million grain legume accessions are conserved in genebanks, of which, ICRISAT genebank holds ~50,000 accessions of cultivated species and wild relatives of chickpea, pigeonpea, and groundnut from 133 countries. These genetic resources are reservoirs of many useful genes for the present and future crop improvement programs. Representative subsets in the form of core and mini core collections have been used to identify trait-specific genetically diverse germplasm for use in breeding and genomic studies in these crops. Chickpea, groundnut and pigeonpea have moved from ‘orphan’ to ‘genomic resources rich crops’. The chickpea and pigeonpea genomes have been decoded, and the sequences of groundnut genome will soon be available. With the availability of these genomic resources, the germplasm curators, breeders and molecular biologists will have abundant opportunities to enhance the efficiency of genebank operations, mine allelic variations in germplasm collection, identify genetically diverse germplasm with beneficial traits, broaden the cultigen’s genepool, and accelerate the cultivar development to address new challenges to production, particularly with respect to climate change and variability. Marker-assisted breeding approaches have already been initiated for some traits in chickpea and groundnut, which should lead to enhanced efficiency and efficacy of crop improvement. Resistance to some pests and diseases has been successfully transferred from wild relatives to cultivated species

Diversidade morfológica de frutos e sementes de baru (Dipteryx alata Vog.) Morphological diversity of fruits and seeds of baru (Dipteryx alata Vog.)

O objetivo deste estudo foi identificar caracteres morfológicos distintos que possibilitem agrupar plantas semelhantes pertencentes a populações de baru (Dipteryx alata Vog.). Foram marcadas 63 plantas nos estados de Goiás e Minas Gerais. Avaliaram-se 20 frutos e sementes por planta, coletados no chão em 1994 e 1995. Mediram-se os parâmetros: peso, comprimento, largura e espessura dos frutos e das respectivas sementes, e cor do tegumento das sementes. Realizaram-se análises de componentes principais e de agrupamento. Observou-se variabilidade entre plantas nos frutos e nas sementes de baru. A análise dos componentes principais mostrou que a distribuição espacial dos dados é da forma contínua. Os dois primeiros componentes explicaram 75% e 80% da variação total das características morfológicas em 1994 e 1995, respectivamente. Todas as variáveis foram importantes na discriminação dos grupos. As configurações de quatro a seis grupos foram consistentes nos dois anos. Menos da metade das plantas permaneceu no mesmo grupo nos dois anos. Isto evidencia que os frutos e sementes possuem variação anual quanto às suas características morfológicas, embora existam exceções. A obtenção de grupos distintos indica presença de variabilidade genética no material coletado.<br>The aim of this study was to identify distinct morphological characters that may group similar plants in populations of "baru" (Dipteryx alata Vog.). Sixty three plants were marked in Goiás and Minas Gerais States, of which 20 fruits and seeds were evaluated, collected from the ground in 1994 and 1995. The following measurements were taken: weight, length, width and dimension of fruits and its respective seeds, and color of seed tegument. Analysis of principal components and cluster analysis were performed. Variances between plants were observed but not within plants. The analysis of principal components showed continuous spatial distribution of the data. The first two components explained 75% and 80% of total variance of morphological characters in 1994 and 1995, respectively. All variables were important for discrimination of groups. The configurations of four to six groups were consistent for both years. Less than half of trees remained in the same group in both years. This shows that fruit and seeds may have annual variation for morphological characters, though exceptions were observed. Distinct grouping indicates presence of genetic variability within material collected