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Fusarium wilt caused by F. oxysporum f. sp. ciceris causes extensive damage to chickpea (Cicer arietinum L.) in many parts of the world. In the central part of India, pathogen race 2 (Foc 2) causes severe yield losses. We initiated molecular marker-assisted backcrossing (MABC) using desi cultivar, Vijay, as a donor to introgress resistance to this race (Foc2) in Pusa 256, another elite desi cultivar of chickpea. To confirm introgression of resistance for this race, foreground selection was undertaken using two SSR markers (TA 37 and TA110), with background selection to observe the recovery of recurrent parent genome using 45 SSRs accommodated in 8 multiplexes. F 1 plants were confirmed with molecular markers and backcrossed with Pusa 256, followed by cycles of foreground and background selection at each stage to generate 161 plants in BC 3 F 2 during the period 2009-2013. Similarly, 46 BC 3 F 1 plants were also generated in another set during the same period. On the basis of foreground selection, 46 plants were found homozygotes in BC 3 F 2 . Among them, 17 plants recorded >91% background recovery with the highest recovery percentage of 96%. In BC 3 F 1 also, 14 hybrid plants recorded a background recovery of >85% with the highest background recovery percentage of >94%. The identified plants were selfed to obtain 1341 BC 3 F 3 and 2198 BC 3 F 2 seeds which were screened phenotypically for resistance to fusarium wilt (race 2) besides doing marker analysis. Finally, 17 BC 3 F 4 and 11 BC 3 F 3 lines were obtained which led to identification of 5 highly resistant lines of Pusa 256 with Foc 2 gene introgressed in them. Development of these lines will help in horizontal as well as vertical expansion of chickpea in central part of India.

Chickpea (Cicer arietinum L.) is the third most important cool season food legume, cultivated in arid and semi-arid regions of the world. The goal of this study was to develop novel molecular markers such as microsatellite or simple sequence repeat (SSR) markers from bacterial artificial chromosome (BAC)-end sequences (BESs) and diversity arrays technology (DArT) markers, and to construct a high-density genetic map based on recombinant inbred line (RIL) population ICC 4958 (C. arietinum)×PI 489777 (C. reticulatum). A BAC-library comprising 55,680 clones was constructed and 46,270 BESs were generated. Mining of these BESs provided 6,845 SSRs, and primer pairs were designed for 1,344 SSRs. In parallel, DArT arrays with ca. 15,000 clones were developed, and 5,397 clones were found polymorphic among 94 genotypes tested. Screening of newly developed BES-SSR markers and DArT arrays on the parental genotypes of the RIL mapping population showed polymorphism with 253 BES-SSR markers and 675 DArT markers. Segregation data obtained for these polymorphic markers and 494 markers data compiled from published reports or collaborators were used for constructing the genetic map. As a result, a comprehensive genetic map comprising 1,291 markers on eight linkage groups (LGs) spanning a total of 845.56 cM distance was developed (http://cmap.icrisat.ac.in/cmap/sm/cp/thudi/). The number of markers per linkage group ranged from 68 (LG 8) to 218 (LG 3) with an average inter-marker distance of 0.65 cM. While the developed resource of molecular markers will be useful for genetic diversity, genetic mapping and molecular breeding applications, the comprehensive genetic map with integrated BES-SSR markers will facilitate its anchoring to the physical map (under construction) to accelerate map-based cloning of genes in chickpea and comparative genome evolution studies in legumes.

Chickpea ( Cicer arietinum L.) is the second most important cool season food legume cultivated in arid and semiarid regions of the world. The objective of the present study was to study variation for protein content in chickpea germplasm, and to find markers associated with it. A set of 187 genotypes comprising both international and exotic collections, and representing both desi and kabuli types with protein content ranging from 13.25% to 26.77% was used. Twenty-three SSR markers representing all eight linkage groups (LG) amplifying 153 loci were used for the analysis. Population structure analysis identified three subpopulations, and corresponding Q values of principal components were used to take care of population structure in the analysis which was performed using general linear and mixed linear models. Marker-trait association (MTA) analysis identified nine significant associations representing four QTLs in the entire population. Subpopulation analyses identified ten significant MTAs representing five QTLs, four of which were common with that of the entire population. Two most significant QTLs linked with markers TR26.205 and CaM1068.195 were present on LG3 and LG5. Gene ontology search identified 29 candidate genes in the region of significant MTAs on LG3. The present study will be helpful in concentrating on LG3 and LG5 for identification of closely linked markers for protein content in chickpea and for their use in molecular breeding programme for nutritional quality improvement. [ABSTRACT FROM AUTHOR]

Fusarium wilt ( Fusarium udum Butler) is a soil borne disease of pigeonpea which causes substantial yield losses. The disease can occur at any stage of plant development, from the young seedling to the pod filling stage. Though resistance is simply inherited, transfer to locally adapted cultivars has been difficult due to linkage drag and difficulty in accurate phenotyping, except in sick plots. An attempt was made to identify RAPD markers associated with wilt phenotype by using F2 populations derived from contrasting parents; GSl (susceptible) ‘ICPL87119 (resistant) and GS1’ ICP8863 (resistant). Parents and F2s were grown in a national Fusarium sick-plot at Gulbarga, India and phenotyped as resistant or susceptible during the entire crop growth period. In both the crosses, resistance to wilt segregated as a monogenic dominant character. DNA samples extracted from sick plot grown, early seedling stage plants of parents and 254 F2 plants of GS1 × ICPL87119 were held separately for marker identification. PCR reactions using 340 random decamer primers with genomic DNA of parents resulted in detection of 45 polymorphic amplicons from 39 primers. PCR testing of bulked DNA from subsets of resistant and susceptible plants revealed the presence of two amplicons at 704 bp and 500 bp (OPM03704 and OPAC11500) with susceptibility. Analysis of individual F2 plants showed a segregation ratio of 3: 1 for the presence: absence of the amplicon in both crosses. Considering the wilt reaction and susceptibility-linked RAPD marker, it was possible to deduce genotype of every F2 plant and the genotypic ratio for wilt reaction was 1RR: 2Rr: 1rr, as expected. [ABSTRACT FROM AUTHOR]