Strategies for pigeonpea improvement

In order to feed an ever-increasing population, it is essential to deal yield reducing factors. Climate smart crop varieties that yield more with fewer inputs will be required to achieve the success. In this scenario pigeonpea plays an important role as it can stand in relatively harsh environmental conditions. Hybrid breeding along with the pure line breeding, genetic resources and genomics advances are enriching this crop. However, the pigeonpea improvement program must be re-oriented in order to deal with the yield-reducing factors and to break the yield plateau

EFFICACY OF BRODIFACOUM (TALON) BAIT AGAINST THREE RODENT SPECIES

Brodifacoum was fed to three rodent species, viz., M. hurrianae, R. rattus and F. pennanti, using a no-choice feeding trial for 7 days at various concentrations--0.005%, 0.0025% and 0.00125%. The compound was found effective, palatable, developed no sign of poison bait-shyness but indicated a slight aversion of poison. The death of the animals was due to pulmonary distress and hemorrhage

On Generalized Fractional Kinetic Equations

In a recent paper, Saxena et al. [1] developed the solutions of three generalized fractional kinetic equations in terms of Mittag-Leffler functions. The object of the present paper is to further derive the solution of further generalized fractional kinetic equations. The results are obtained in a compact form in terms of generalized Mittag-Leffler functions. Their relation to fundamental laws of physics is briefly discussed.Comment: 10 pages, LaTe

Some generating functions for the Jacobi polynomials

AbstractA certain family of generating functions for the classical Jacobi polynomials, given earlier by R.K. Saxena and Z. Hussain [1], are observed here to be derivable directly from some known (and readily available) results in the literature. An interesting generalization of the aforementioned generating functions emerges naturally in the process. Some relevant connections of these results with various known generating functions are also pointed out

PRIL_A, PRIL_B and PRIL_C: Pigeonpea Recombinant Inbred Line Mapping Populations Segregating for Resistance to Fusarium Wilt and Sterility Mosaic Disease

Pigeonpea [Cajanus cajan (L) Millsp] bi-parental populations segregating for various traits of interest are being developed. The three most advanced populations, named PRIL_A, PRIL_B and PRIL_C (Pigeonpea Recombinant Inbred Line, population A, B and C) have reached F6 generation. PRIL_A: derived from the cross ICPB 2049 x ICPL 99050 segregates for fusarium wilt (FW), 329 lines. PRIL_B: derived from the cross ICPL 20096 x ICPL 332 segregates for FW and sterility mosaic disease (SMD), 342 lines. PRIL_C: derived from the cross ICPL 20097 × ICP 8863 segregates for SMD, 366 lines. Marker genotyping of the parental lines, however, showed low level of genetic variation. After screening over 4,616 (3,000 simple sequence repeats (SSRs) and 1,616 single nucleotide polymorphism (SNPs)) markers on parental genotypes of each mapping population, a total of 159 (104 SSRs and 55 SNPs), 80 (52 SSRs and 28 SNPs) and 157 (143 SSRs and 14 SNPs) markers were found polymorphic for ICPB 2049 vs ICPL 99050, ICPL 20096 vs ICPL 332 and ICPL 20097 vs ICP 8863, respectively. The polymorphic markers will be used for constructing genetic linkage maps. The populations will be screened for FW and SMD in 2012-13, while marker-trait association analysis will also be conducted to understand the genetic basis of resistance to these diseases. Further selection from the above indicated mapping populations during 2011-12, on an effort initiated in 2010, resulted in 28 lines with high yield (up to 2.4 t/ha) and disease resistanc

Reaction-diffusion systems and nonlinear waves

The authors investigate the solution of a nonlinear reaction-diffusion equation connected with nonlinear waves. The equation discussed is more general than the one discussed recently by Manne, Hurd, and Kenkre (2000). The results are presented in a compact and elegant form in terms of Mittag-Leffler functions and generalized Mittag-Leffler functions, which are suitable for numerical computation. The importance of the derived results lies in the fact that numerous results on fractional reaction, fractional diffusion, anomalous diffusion problems, and fractional telegraph equations scattered in the literature can be derived, as special cases, of the results investigated in this article.Comment: LaTeX, 16 pages, corrected typo

Toward the sequence-based breeding in legumes in the post-genome sequencing era

Efficiency of breeding programs of legume crops such as chickpea, pigeonpea and groundnut has been considerably improved over the past decade through deployment of modern genomic tools and technologies. For instance, next-generation sequencing technologies have facilitated availability of genome sequence assemblies, re-sequencing of several hundred lines, development of HapMaps, high-density genetic maps, a range of marker genotyping platforms and identification of markers associated with a number of agronomic traits in these legume crops. Although marker-assisted backcrossing and marker-assisted selection approaches have been used to develop superior lines in several cases, it is the need of the hour for continuous population improvement after every breeding cycle to accelerate genetic gain in the breeding programs. In this context, we propose a sequence-based breeding approach which includes use of independent or combination of parental selection, enhancing genetic diversity of breeding programs, forward breeding for early generation selection, and genomic selection using sequencing/genotyping technologies. Also, adoption of speed breeding technology by generating 4–6 generations per year will be contributing to accelerate genetic gain. While we see a huge potential of the sequence-based breeding to revolutionize crop improvement programs in these legumes, we anticipate several challenges especially associated with high-quality and precise phenotyping at affordable costs, data analysis and management related to improving breeding operation efficiency. Finally, integration of improved seed systems and better agronomic packages with the development of improved varieties by using sequence-based breeding will ensure higher genetic gains in farmers’ fields

Genetic diversity and demographic history of Cajanus spp. illustrated from genome-wide SNPs

Understanding genetic structure of Cajanus spp. is essential for achieving genetic improvement by quantitative trait loci (QTL) mapping or association studies and use of selected markers through genomic assisted breeding and genomic selection. After developing a comprehensive set of 1,616 single nucleotide polymorphism (SNPs) and their conversion into cost effective KASPar assays for pigeonpea (Cajanus cajan), we studied levels of genetic variability both within and between diverse set of Cajanus lines including 56 breeding lines, 21 landraces and 107 accessions from 18 wild species. These results revealed a high frequency of polymorphic SNPs and relatively high level of cross-species transferability. Indeed, 75.8% of successful SNP assays revealed polymorphism, and more than 95% of these assays could be successfully transferred to related wild species. To show regional patterns of variation, we used STRUCTURE and Analysis of Molecular Variance (AMOVA) to partition variance among hierarchical sets of landraces and wild species at either the continental scale or within India. STRUCTURE separated most of the domesticated germplasm from wild ecotypes, and separates Australian and Asian wild species as has been found previously. Among Indian regions and states within regions, we found 36% of the variation between regions, and 64% within landraces or wilds within states. The highest level of polymorphism in wild relatives and landraces was found in Madhya Pradesh and Andhra Pradesh provinces of India representing the centre of origin and domestication of pigeonpea respectively. © 2014 Saxena et al

Solution of generalized fractional reaction-diffusion equations

This paper deals with the investigation of a closed form solution of a generalized fractional reaction-diffusion equation. The solution of the proposed problem is developed in a compact form in terms of the H-function by the application of direct and inverse Laplace and Fourier transforms. Fractional order moments and the asymptotic expansion of the solution are also obtained.Comment: LaTeX, 18 pages, corrected typo

Pigeonpea seed systems in Asia

Pigeonpea seed systems consist of the formal and informal seed sector. However, the informal seed sector dominates the seed production system. Majority of rainfed farmers who grow pigeonpea (about 80% - 90%) save a part of their produce as seed requirement. In the formal seed sector, government agencies and private companies are involved in production and distribution of quality seeds of improved varieties and hybrids. Role of private sector diffusion in pigeonpea market is not encouraging owing to lack of commercial perspective in the crop and other factors. The integrated approach that takes into cognizance the formal and informal seed sector in breeding, seed production and distribution has shown to have promising potential for improving seed supply to smallholder farmers. Moreover, any seed system, for that matter, requires a regulatory framework as well as a seed policy that considers regulations of an expanding and diversifying seed sector for the benefit of the farmers engaged in the seed production system