Research Notes : India : Intra-plant variation in mutation frequency and spectrum in soybean

Upadhyaya (1976) observed that the number of mutant plants was exceedingly low in segregating M2 progenies in soybean. In M3 progenies of normal M2 plants, the number of segregating progenies was also not very high as compared with nonsegregating progenies. But, all the segregating progenies in MJ generation showed an excellent fit to the 3 normal:l mutant ratio, indicating mutant as a monogenic recessive trait. Such a situation was encountered in many cases of albino, yellow leaf, crinkled leaf, and sterile mutants

Geotechnical Problems Encountered During the Excavation of Underground Cavities for Varahi Hydro Electric Project

Varahi river in Karnataka State, India originates on the Western Ghats and is harnessed for power generation by constructing three dams. The water is conveyed through two inclined pressure shaft to the underground power house below the Ghats. The underground power house of the Varahi Hydro Electric Project executed by the Karnataka Power Corporation has 2 units of 135 MW each in the first stage with a provision to add two more identical units. Three underground cavities are excavated parallel to one another for housing the rotary valves, generators and the transformers respectively and are at a gee-static head of about 230 m. The paper deals with a case history of the excavation practice and the stabilisation measures adopted during the excavation of the cavities for housing the underground power house complex of the Varahi Hydro Electric Project in Karnataka, India

Genetic resources of pulse crops - present status and future plans

Plant genetic resources (PGR) are essential for a sound and successful crop improvement programme and insurance against nature's vagaries. India has been considered a p~imary centre of diversity for urdbean, mothbean and pige~pea; a secondary centre of diversity for cowpea, and regional (Asiatic) centre of diversity for crops like chickpea and mungbean. Several exploration missions have been undertaken for collection of available indigenous diversity in different legume crops especially in chickpea, pigeon pea, urdbean, mungbean, cowpea, peas, lentil, lathyrus, mothbean, horsegram and cowpea. About 42,425 accessions representing 26 pulse crops are stored at -20°C in long-term repository of. National Gene Bank of NBPGR. Evaluation of germplasm has led to the release of more than 60% of total pulse varieties as direct selection from the germplasm in India. PGRs are also being used in hybridization programmes for genetic upgradation of cultivars as well as creation of new varieties. So far, 434 varieties have been developed in different pulse crops following this approach. However, due to rapid agro-ecological changes, many species, old and primitive cultivars, land raceS and their wild relatives are being eroded. Hence, concerted and systematic efforts for collection, conservation, evaluation, and utilization of germpJasm need to be undertaken

Multiple resistant and nutritionally dense germplasm identified from mini core collection in peanut

Peanut (Arachis hypogaea L.) is extensively grown by resource-poor farmers in the semiarid tropics where many abiotic and biotic stresses limit the crop's productivity and seed quality. Peanut cultivars with enhanced host-plant resistance, adaptation to abiotic stress, input-use efficiency, and yield potential will maximize yield gains and minimize inputs to sustain production. The peanut mini core collection was evaluated for agronomic traits in multienvironment trials at Patancheru, India. The published information on 184 mini core accessions revealed 28 accessions resistant to abiotic stress, 30 resistant to biotic stress, and 18 that were agronomically desirable but susceptible to stresses, while 16 were seed nutrient dense. The mini core is part of the composite collection, which was previously genotyped using SSRs. The agronomic evaluation, stress response, and nutritional information together with genotyping data were used to identify genetically diverse germplasm with agronomically beneficial traits: ICG 12625 (resistance to drought, low temperature, late leaf spot [LLS], Aspergillus flavus Link, bacterial wilt; high oil and good oil quality) and ICG 442 (resistance to drought, salinity, P deficiency); ICG 12625 and ICG 2381 (resistance to rust, A. flavus; good oil quality); ICG 12697 (resistance to LLS, rust, A. flavus) and ICG 6022 (resistance to early leaf spot [ELS], LLS); ICG 14710 (high oil, Fe, Zn) and ICG 7963 (high protein, Fe, Zn); ICG 11426 (resistance to ELS, LLS, rust) and ICG 5221 (high Fe and Zn and good oil quality). Accessions with adaptation to rainy and/or post-rainy environments were ICG# 434, 5745, 8285, 10036, 11088, 11651, 12625, 15042, and 15419. These accessions are ideal genetic resources that may be used to develop agronomically superior and nutritionally enhanced peanut cultivars with multiple resistances to abiotic and biotic stresses

Fission of a multiphase membrane tube

A common mechanism for intracellular transport is the use of controlled deformations of the membrane to create spherical or tubular buds. While the basic physical properties of homogeneous membranes are relatively well-known, the effects of inhomogeneities within membranes are very much an active field of study. Membrane domains enriched in certain lipids in particular are attracting much attention, and in this Letter we investigate the effect of such domains on the shape and fate of membrane tubes. Recent experiments have demonstrated that forced lipid phase separation can trigger tube fission, and we demonstrate how this can be understood purely from the difference in elastic constants between the domains. Moreover, the proposed model predicts timescales for fission that agree well with experimental findings

Grand canonical ensemble in generalized thermostatistics

We study the grand-canonical ensemble with a fluctuating number of degrees of freedom in the context of generalized thermostatistics. Several choices of grand-canonical entropy functional are considered. The ideal gas is taken as an example.Comment: 14 pages, no figure

Development of cost-effective SNP assays for chickpea genome analysis and breeding

A total of 1499 ESTs generated from 26 different Cicer species, available in the public domain at the time of analysis, were used for in silico identification of SNPs using the bioinformatic tools developed at the International Crops Research Institute for the Semi-Arid Tropics (ICRISAT) (http://hpc.icrisat.org/PBSWeb). Cluster analysis provided a total of 118 clusters, of which 11 clusters contained sequences from more than one Cicer species. Further, these clusters were assembled into 19 contigs and 184 putative SNPs were identified in 15 contigs. However, only 73 SNPs involved restriction enzyme sites for development of the CAPS assays as identified through the SNP2CAPs program. Primer pairs were designed for only 8 contigs (CL3a, CL3c, CL3d, CL3e, CL4a, CL10, CL20 and CL99) which had SNPs, resulting in putative recognition sites to commonly used restriction enzymes. Results of the demonstrates the utility of Cicer EST resources and the availability of bioinformatics analysis pipelines for the large-scale identification of SNPs on the HPC (High Performance Computer) at ICRISAT and the development of costeffective CAPS assay for SNP genotyping. It is anticipated that the availability of large number of ESTs from more than one genotype of cultivated chickpea (C. arietinum) in the near future will make it possible to develop larger number of SNPs in cultivated chickpea germplasm for genome analysis and breeding application