Mapping QTL associated with yield and yield components and Ascochyta blight in chickpea

Non-Peer ReviewedChickpea (Cicer arietinum L.) is the third important legume crop in production among the world pulse crops. A better understanding of the genetic basis of yield and disease traits and their association with flowering time could contribute to their use in the breeding strategies of the crop in the Canadian Prairies. The objective of this study was to evaluate a set of Recombinant Inbred Lines (RILs) of chickpea for yield and disease traits and to locate Quantitative Trait Loci (QTL) associated with these traits. This study used a RIL population derived from across between ICCV 96029 (a desi market class, an extra early maturing, highly susceptible to ascochyta blight and CDC Frontier (a kabuli market class, late maturing, moderately resistant to ascochyta blight. A population consisting of 92 RILs together with the 2 parents were grown in a field at Elrose, Saskatchewan in 2011 in a micro plot with 2 replications. Measurements on agronomic traits were made on an individual plant basis and the means of five plants were used for analysis. Plants were air-dried at 35°C for 48 h before measuring the above-ground biomass. Traits measured were grain yield (in gm /plant), above ground biomass (in g/ plant), number of grains /plant, number of pods/ plant, and 1000 seed weight. Harvest index (HI) = grain weight/total above ground dry weight. The result indicated that, there was significant difference in plant height (in cm), number of seeds /plant, number of seeds/pod, 1000 seeds weight (in gm/plant) and Harvest Index (%). The same lines were evaluated in the greenhouse for Ascochyta blight reaction and in the growth chambers for their flowering responses to different photoperiod. Mapping of QTL will be performed on the line mean data for single years of the field observation and for different photoperiod treatments in the growth chamber

Iron biofortification of chickpea (Cicer arietinum L.): a tale of addressing Fe deficiency problem in less fed population

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Implementation of marker-assisted selection for lodging resistance in pea breeding

Non-Peer ReviewedLodging resistance is a key criterion in pea breeding programs. In traditional breeding, a large number of lines are discarded in F3 or later generations, because of susceptibility to lodging and much labor and other costs are wasted. Implementation of selection using molecular markers for lodging resistance at earlier generations will significantly enhance the efficiency of the pea breeding process. Ten F2 populations consisting of a total of 869 plants were grown in the field in Saskatoon in the summer of 2002. These 10 populations were derived from crosses between the lodging susceptible variety Carrera, crossed with ten other lodging resistant lines. DNA samples were extracted from each individual plant. Each plant was scored for the presence of coupling phase linked SCAR markers A001 and A002, as well as a repulsion phase linked SCAR marker A004. The results showed that the frequency of marker presence is similar to the estimated frequency, obeying the rule of independent single gene segregation. Chi-Square analysis showed that the combination of A001 and A004 markers also followed a two gene model (P>0.05) in 8 populations. Due to linkage between A001 and A002 markers, population No. 3 and No. 4 did not follow the two or three independent gene segregation model. F3 populations will be planted in the field in 2003 to evaluate the effectiveness of Marker Assist Selection for lodging resistance in pea

Moving pulse crop breeding into the 21st century

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Rapid introgression of common bacterial blight resistance genes into dry bean elite varieties by marker-assisted backcrossing

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Pulse crop breeding update

Non-Peer ReviewedThe pulse crop breeders at the Crop Development Centre (CDC)/Department of Plant Sciences are developing improved cultivars of lentil, field pea, chickpea, dry bean and faba bean for producers in western Canada. General objectives include improvement of yield, disease resistance, earliness, and quality for diverse markets

RAPD and AFLP markers linked to anthracnose resistance gene in PI 320937 lentil (Lens culinaris Medik.)

Non-Peer ReviewedColletotrichum truncatum (Schwein.) Andrus & W.D. Moore is the causal fungus for anthracnose disease in lentils. A germplasm accession, ‘PI 320937’, is among the lines used as a resistance source to develop cultivars in the breeding program. A cross of Eston (susceptible) and PI 320937 (resistant) was used to develop 147 recombinant inbred lines (RILs) to study the genetics of resistance and identify markers associated to the resistance gene. The F5:6 RILs were inoculated with C. truncatum isolate 95B36 at 105 conidia ml-1 and scored for anthracnose reactions over 2 replications in the greenhouse. About 600 RAPD and 10 AFLP primers were screened. We used bulk segregant analysis to construct contrasting DNA bulks, one containing only resistant and the other only susceptible plants based on the greenhouse tests. These polymorphic markers between parental lines were used to genotype RILs and make linkage analysis. Segregation data indicated that a single major gene (LCt-2) confers resistance. Minor genes also modified the level of resistance. Two RAPD markers; namely, OPE O61250 and UBC 704700 were linked in repulsion and coupling at 6.4 and 10.8 cM, respectively, to the resistance gene. Also, 3 AFLP markers were identified within 30 cM distance from the resistance locus. These markers will be useful in lentil breeding via marker-assisted selection towards developing cultivars with anthracnose resistance

Genetic study of Ascochyta blight resistance in chickpea and lentil

Non-Peer ReviewedAscochyta blight is responsible for severe crop losses in most chickpea and lentil production areas around the world. The research was conducted to study the genetic basis for Ascochyta blight resistance in chickpea and lentil by means of QTL analysis, and PCR-based approaches to identify resistance gene analogues (RGA) sequences in the lentil genome. An AFLP and three SSR markers were linked to the gene(s) for Ascochyta resistance in a chickpea population derived from a cross between CDC Chico and CDC Marengo. Two QTL that explained 36 % and 29 % of the disease reaction variability were identified in a lentil RI population derived from a cross between ILL5588 and L692-16-1. These markers were converted into SCAR markers to simplify their use for marker-assisted selection

Genetic improvement of chickpea for western Canada

Non-Peer ReviewedThe chickpea crop has experienced a roller-coaster ride over the past decade in western Canada. Production rose rapidly in the late 1990’s, followed by dramatic declines in the past two years. Instability can be attributed to many factors including commodity prices, erratic weather patterns, Ascochyta blight and late maturity. This paper summarizes current research on genetic improvement of chickpea at the University of Saskatchewan, with particular emphasis on efforts to improve Ascochyta blight resistance and to develop varieties with earlier maturity. Under ‘average’ weather conditions, chickpea remains an excellent nitrogen-fixing crop for the Brown and Dark Brown soil zones

Revisiting strategies for breeding anthracnose resistance in lentil: the case with wild species

Non-Peer ReviewedBreeders at the Crop Development Centre (CDC) have up to now only used germplasm resources available in the cultivated lentil to develop new varieties with resistance to diseases. Based on recent studies, the available cultivated germplasm does not offer sufficient genetic variation for resistance to anthracnose and ascochyta diseases. Lentil crop is attacked by two major diseases (anthracnose and ascochyta) that can cause 100% loss in the worst scenarios. Since anthracnose is only a major lentil disease in North America, no work has been done to improve resistance to this disease elsewhere. Wild species of many crops are known to carry many disease resistance genes lacking in the cultivated crop. We began the search for anthracnose resistance in the six wild species of lentil (world collection), of which two can be easily crossed with the cultivated type. Two strains of anthracnose (race 1 and race 2) with varying degrees of virulence were reported. The 2002 field data suggested that some of the Lens ervoides and Lens lamottei accessions exhibited no lesions at all when exposed to the combination of the two anthracnose strains. The cultivated types that show resistance to the less virulent strain were severely affected by anthracnose. In the greenhouse study the wild species were inoculated with the two strains separately and results indicate that no accession is immune to the more virulent type. However, some of the L. ervoides and L. lamottei accessions had good resistance compared to their cultivated counterparts. As a long term strategy, the lentil breeding program at CDC, University of Saskatchewan has a goal of fully utilizing the available resistance sources. However, these two species cannot be easily crossed with the cultivated types using the conventional/manual crossing techniques. A tissue culture procedure involving embryo rescue is used to facilitate crossing. We have been able to successfully rescue some embryos from crosses with Lens ervoides. The hybrid plants produce some fertile seeds which will be evaluated for resistance to both anthracnose and ascochyta. The selected resistant lines will then be backcrossed to the adopted backgrounds in order to deploy resistance genes