Mini Core collection of Chickpea.

A core collection is a chosen subset of large germplasm collection that generally contains about 10% of the total accessions and represents the genetic variability of entire germplasm collection. The purpose of a core collection is to improve the use of genetic resources in crop.......

Genotyping of composite collection of foxtail millet [Setaria italica (L). P. Beauv.]

Not much information is available about the usefulness of foxtail millet germplasm in breeding programmes. A composite collection of 500 accessions has been developed and molecularly profiled using 19 SSRs (Xia et al. 2007; Dida et al. 2007; ICRISAT unpublished data) in high throughput assay (ABI3700)

Phenotypic diversity in groundnut (Arachis hypogaea L.) core collection assessed by morphological and agronomical evaluations

The groundnut (Arachis hypogaea L.) core collection consists of 1704 accessions of which 910 belong to subsp. fastigiata (var. fastigiata, vulgaris, aequatoriana, peruviana) and 794 to subsp. hypogaea (var. hypogaea, hirsuta). This core collection was evaluated for 16 morphological descriptors and for 32 agronomic characteristics, 15 in the 1999 rainy season and 17 in the 1999/2000 postrainy season, to estimate phenotypic diversity and determine importance of different descriptor traits. The two groups differed significantly for all the traits except leaflet surface and oil content. The hypogaea group showed significantly greater mean pod length, pod width, seed length, seed width, yield per plant, and 100-seed weight than the fastigiata group in both seasons whereas it is opposite for plant height, leaflet length, leaflet width and shelling percentage. There were significant phenotypic correlations among the various characteristics. Four of these, days to 50% flowering (r=0.752), leaflet length (r=0.743), pod length (r=0.758), and seed length (r=0.759) in the rainy explained more than 50% variation in the postrainy season. Principal coordinate and principal component analyses showed that 12 morphological descriptors and 15 agronomic traits, respectively, were important in explaining multivariate polymorphism. Leaflet shape and surface, colour of standard petal markings, seed colour pattern, seed width, and protein content did not significantly account for variation in the first five principal coordinates or components of fastigiata and hypogaea types as well as for the entire core collection. This indicates their relatively low importance as groundnut descriptors. The average phenotypic diversity index was similar in both subspecies groups. The Shannon-Weaver diversity index varied among traits between the two groups, and the diversity within a group depended upon the season and traits recorded

Variability for drought resistance related traits in the mini core collection of peanut

Peanut (Arachis hypogaea L.) productivity is low in the semiarid tropics mainly because of drought caused by low and erratic rainfall. Identification of genotypes that have a greater ability to use limited available water is important to enhance productivity of the crop. Water-use efficiency (WUE) is correlated with specific leaf area (SLA) and soil plant analysis development (SPAD) chlorophyll meter reading (SCMR) and both have been suggested as surrogate traits for selecting for WUE in peanut. The present study was conducted to: (i) identify genotypes with high WUE using SLA or SCMR and (ii) evaluate relationship between and relative stability of SCMR and SLA in these genotypes. The 184 mini core entries, consisting of 37 fastigiata, 58 vulgaris, 85 hypogaea, two peruviana, and one each of aequitoriana and hirsuta and four control cultivars, M 13, Gangapuri, ICGS 44 and ICGS 76 were evaluated for SLA, SCMR, and 19 vegetative, reproductive, and quality traits in the 2001 rainy and 2001–2002 postrainy seasons at ICRISAT Center. Data were analyzed by REML analysis. Seasons were significant for all traits. Variances due to genotypes were significant for SCMR and SLA at 60 and 80 d after sowing (DAS) and other traits except pods per plant, yield per plant, haulm yield per plot, and protein and oil contents. The genotype x season interactions were significant for both SCMR and SLA at 80 DAS only and for all other quantitative traits except number of primary branches, and pod width. The SCMR values at different stages and seasons were more positively correlated with each other than the correlation of SLA values together. SCMR and SLA were negatively correlated. SCMR values were more strongly correlated with pod yield and other economic traits such as 100-seed weight at both 60 and 80 DAS than SLA. On the basis of higher heritability and lower proportion of genotype x season interaction variance to phenotypic variance, SCMR appeared to be more stable than SLA. On the basis of SLA and SCMR values compared with the control cultivar, five vulgaris and 13 hypogaea accessions were selected. These accessions and control cultivars were grouped by scores of the first 15 principal components (PCs). The clustering by UPGMA method indicated that the selected accessions were diverse from the control cultivars and can be used in the peanut improvement programs to develop cultivars with a broad genetic base

Wet or dry? Impact of conditioning seed in germplasm conservation strategies

Seed deterioration is a continuous process and we need techniques that prolong longevity. A combination of 3-7% seed moisture content (mc) and a storage temperature below 0°C is suitable for long-term preservation of germplasm samples. When crop seeds are dried to low moisture levels, they decrease in weight and volume, and might develop seed coat cracks if dried too rapidly. Dried seeds are susceptible to mechanical injuries, especially when they absorb water too quickly, and suffer what is called imbibition injury

Molecular characterisation of groundnut (Arachis hypogaea L.) composite collection

ICRISAT and EMBRAPA jointly developed a global composite collection, consisting of 1000 diverse groundnut accessions, which included 184 groundnut mini core subset (Upadhyaya et al. 2002), another 184 mini core comparator, 110 accessions from Asia core and mini core, 408 elite germplasm/cultivars and trait-specific (resistance to biotic and abiotic stresses, early maturity and/or fresh seed dormancy, large-seed, high shelling percentage, high oil and/or protein content, and interspecific derivatives) accessions, and 114 wild Arachis accessions. This composite collection has been molecularly profiled using 21 SSRs in high throughput assay (ABI3700)

Genotyping pigeonpea composite collection using SSR markers

Pigeonpea (Cajanus cajan (L.) Millspaugh) is the sixth most important food legume grown as a field and/or backyard crop in over 82 countries across the globe. However, as a regular annual crop it is grown only in 19 countries on 4.4 million ha producing 3 million t of grains. • About 92% of the area is in developing countries.India (3.2 million ha), Myanmar (0.48 million ha), Kenya (0.15 million ha) and Malawi (0.12 million ha) are the major pigeonpea growing countries. • Primarily grown as dry seeds, and green vegetable. • Pigeonpea is a good source of vegetarian protein, soil enricher, fodder, fuel wood, and is also good for arresting soil erosion...........

Mini Core collection of Sorghum.

Global Sorghum [Sorghum bicolor (L.) Moench] germplasm collections at ICRISAT genebank Mini Core Collections exceeds 37,000. A core collection (2247 accessions) was developed in 2001 to enable Reference Set researchers to have access to smaller set of germplasm. ...................

Composite collection of Finger Millet.

Finger millet (Eleusine coracana (L.) Gaertn), belongs to genus Eleusine in the tribe Eragrostideae family Poaceae (Gramineae), and subfamily Chloridoideae, self pollinating, ranks fourth in importance among millets in the world after sorghum, pearl millet, and foxtail millet. It is a tetraploid species with 2n=36, and self pollinating...............