Search Results: 1 - 10 of 100 matches for " "
All listed articles are free for downloading (OA Articles)
Page 1 /100
Display every page Item
New microsatellite markers for pigeonpea (cajanus cajan (L.) millsp.)
DA Odeny, Jayashree B, C Gebhardt, J Crouch
BMC Research Notes , 2009, DOI: 10.1186/1756-0500-2-35
Abstract: Primers were designed for 113 pigeonpea genomic SSRs, 73 of which amplified interpretable bands. Thirty-five of the primers revealed polymorphism among 24 pigeonpea breeding lines. The number of alleles detected ranged from 2 to 6 with a total of 110 alleles and an average of 3.1 alleles per locus. GT/CA and GAA class of repeats were the most abundant di-nucleotide and tri-nucleotide repeats respectively. Additionally, 220 soybean primers were tested in pigeonpea, 39 of which amplified interpretable bands.Despite the observed morphological diversity, there is little genetic diversity within cultivated pigeonpea as revealed by the developed microsatellites. Although some of the tested soybean microsatellites may be transferable to pigeonpea, lack of useful polymorphism may hinder their full use. A robust set of markers will still have to be developed for pigeonpea genome if molecular breeding is to be achieved.The increasing concern of the effect of global climate change and its likely impact on agriculture has stimulated scientists to search for crops that can withstand extreme environmental conditions. Among legumes, pigeonpea {Cajanus cajan (L.) Millspaugh} (2n = 22) has attracted attention as being both drought-tolerant [1] and highly nutritious [2]. Extensive morphological variation within the genus Cajanus as a whole and in cultivated species in particular has always led to the assumption that there exists abundant genetic diversity within the cultivated species. To the contrary, molecular studies have reported extremely low levels of polymorphism within the cultivated species compared to its wild relatives [3,4]. Such findings suggest that efforts towards the development of a linkage map of pigeonpea should focus on the use of an interspecific cross, and the development of a substantially high number of markers. We report the development of new 36 polymorphic simple sequence repeat (SSR) markers that will be an asset in characterising and understanding the nat
Evaluation of the shoot regeneration response in tissue culture of pigeonpea (Cajanus cajan [L.] Millsp.) varieties adapted to eastern and southern Africa
S de Villiers, Q Emongor, R Njeri, E Gwata, D Hoisington, I Njagi, S Silim, K Sharma
African Journal of Biotechnology , 2008,
Abstract: Seven varieties of pigeonpea (Cajanus cajan [L.] Millsp.) of varying growth durations and adapted to a wide range of environments across eastern and southern Africa were evaluated for their shoot regeneration response in tissue culture. On a standardized shoot regeneration medium, the short duration varieties (ICPV 88091 and ICPV 86012) generally responded faster and better than the medium duration (ICEAP 00554 and ICEAP 00557) and long duration (ICEAP 00020, ICEAP 00040 and ICEAP 00053) varieties. However, all the tested varieties produced healthy rooted plants in vitro that could be transferred to the greenhouse where they exhibited normal growth, flowering and viable seed set. This study established the basis for genetic engineering of African pigeonpea varieties.
Inheritance of sterility mosaic disease resistance to Bangalore and Patancheru isolates in pigeonpea (Cajanus cajan (L.) Millsp.)
B.N. Gnanesh,, K.N. Ganapathy, B.C. Ajay, M. Byre Gowda
Electronic Journal of Plant Breeding , 2011,
Abstract: Sterility mosaic disease (SMD), is an important biotic constraint in pigeonpea (Cajanus cajan (L.) Millsp.) in Indiansubcontinent. It is caused by a virus and transmitted by eriophyid mites, Aceria cajani Channabasavanna. A comprehensive studyof variability in the sterility mosaic pathogen revealed the occurrence of five different isolates in India. Amongst them, threedistinct isolates have been characterised, viz., Bangalore, Patancheru and Coimbatore. Studies were conducted at Bangalore andPatancheru to determine the inheritance of resistance to Bangalore and Patancheru isolates of the SMD involving a resistant (ICP7035) and susceptible (TTB 7) genotypes. Observations in parents, F1 indicated dominance of susceptibility over resistance. Thedisease reaction of the individual F2 plant derived F3 families for Patancheru isolate was controlled by two genes with dominanceepistasis and for Bangalore isolate, absence of resistant plants indicate action of two or more genes in controlling resistance toSMD.
Growth and Yield Potentials of Various Pigeonpea (Cajanus cajan L. Millsp) Cultivars
N.M. Soomro,F.C. Oad,G.N. Sohu,N.L. Oad
Journal of Applied Sciences , 2001,
Abstract: The experiment was conducted at Z.A. Bhutto Agricultural College, Dokri Larkana, Sindh, Pakistan in experimental design of RCBD, replicated four times in net plot size of 3m x 5m, where 74078-1, ICPL-4, Local check, ICPL-2, ICPL-6, ICPL-84, T-21, ICPL-150 pigeonpea varieties/lines were planted for growth and yield potentials. Among the tested cultivars ICPL-6 was observed as dwarf and appeared to be superior one by recording maximum branches, having early maturity, and attempted maximum number of pods and seed index. ICPL-6 also proved itself as high yielding pigeonpea cultivar by recording 2166.70kg grain yield-ha. Thus, it is recommended the ICPL-6 pigeonpea cultivar should be grown for early maturity and high potential yield.
Antioxidant Activities of Extracts and Main Components of Pigeonpea [Cajanus cajan (L.) Millsp.] Leaves  [PDF]
Nan Wu,Kuang Fu,Yu-Jie Fu,Yuan-Gang Zu,Fang-Rong Chang,Yung-Husan Chen,Xiao-Lei Liu,Yu Kong,Wei Liu,Cheng-Bo Gu
Molecules , 2009, DOI: 10.3390/molecules14031032
Abstract: Antioxidant activities of the aqueous and ethanol extracts of pigeonpea [Cajanus cajan (L.) Millsp.] leaves, as well as petroleum ether, ethyl acetate, n-butanol and water fractions and the four main compounds separated from the ethanol extract, i.e. cajaninstilbene acid (3-hydroxy-4-prenylmethoxystilbene-2-carboxylic acid), pinostrobin, vitexin and orientin, were examined by a DPPH radical-scavenging assay and a β-carotene-linoleic acid test. In the DPPH system, the antioxidant activity of the ethanol extracts was superior to that of the aqueous extracts, with IC50 values were 242.01 and 404.91 μg/mL, respectively. Among the four fractions, the ethyl acetate one showed the highest scavenging activity, with an IC50 value of 194.98 μg/mL. Cajaninstilbene acid (302.12 μg/mL) and orientin (316.21 μg/mL) showed more efficient radical-scavenging abilities than pinostrobin and vitexin. In the β-carotene-linoleic acid test, the inhibition ratio (%) of the ethyl acetate fraction (94.13%±3.41%) was found to be the highest, being almost equal to the inhibition capacity of the positive control BHT (93.89%±1.45%) at 4 mg/mL. Pinostrobin (>500 μg/mL) and vitexin (>500 μg/mL) showed insignificant antioxidant activities compared with cajaninstilbene (321.53 μg/mL) and orientin (444.61 μg/mL). In general, the ethyl acetate fraction of the ethanol extract showed greater activity than the main compounds in both systems, such results might be attributed to the synergistic effects of the components. The antioxidant activities of all the tested samples were concentration-dependent. Based on the results obtained, we can conclude that the pigeonpea leaf extracts may be valuable natural antioxidant sources and are potentially applicable in both medicine and the healthy food industry.
Genetic Patterns of Domestication in Pigeonpea (Cajanus cajan (L.) Millsp.) and Wild Cajanus Relatives  [PDF]
Mulualem T. Kassa, R. Varma Penmetsa, Noelia Carrasquilla-Garcia, Birinchi K. Sarma, Subhojit Datta, Hari D. Upadhyaya, Rajeev K. Varshney, Eric J. B. von Wettberg, Douglas R. Cook
PLOS ONE , 2012, DOI: 10.1371/journal.pone.0039563
Abstract: Pigeonpea (Cajanus cajan) is an annual or short-lived perennial food legume of acute regional importance, providing significant protein to the human diet in less developed regions of Asia and Africa. Due to its narrow genetic base, pigeonpea improvement is increasingly reliant on introgression of valuable traits from wild forms, a practice that would benefit from knowledge of its domestication history and relationships to wild species. Here we use 752 single nucleotide polymorphisms (SNPs) derived from 670 low copy orthologous genes to clarify the evolutionary history of pigeonpea (79 accessions) and its wild relatives (31 accessions). We identified three well-supported lineages that are geographically clustered and congruent with previous nuclear and plastid sequence-based phylogenies. Among all species analyzed Cajanus cajanifolius is the most probable progenitor of cultivated pigeonpea. Multiple lines of evidence suggest recent gene flow between cultivated and non-cultivated forms, as well as historical gene flow between diverged but sympatric species. Evidence supports that primary domestication occurred in India, with a second and more recent nested population bottleneck focused in tropical regions that is the likely consequence of pigeonpea breeding. We find abundant allelic variation and genetic diversity among the wild relatives, with the exception of wild species from Australia for which we report a third bottleneck unrelated to domestication within India. Domesticated C. cajan possess 75% less allelic diversity than the progenitor clade of wild Indian species, indicating a severe “domestication bottleneck” during pigeonpea domestication.
Molecular mapping of QTLs for plant type and earliness traits in pigeonpea (Cajanus cajan L. Millsp.)
Kumawat Giriraj,Raje Ranjeet S,Bhutani Shefali,Pal Jitendra K
BMC Genetics , 2012, DOI: 10.1186/1471-2156-13-84
Abstract: Background Pigeonpea is an important grain legume of the semi-arid tropics and sub-tropical regions where it plays a crucial role in the food and nutritional security of the people. The average productivity of pigeonpea has remained very low and stagnant for over five decades due to lack of genomic information and intensive breeding efforts. Previous SSR-based linkage maps of pigeonpea used inter-specific crosses due to low inter-varietal polymorphism. Here our aim was to construct a high density intra-specific linkage map using genic-SNP markers for mapping of major quantitative trait loci (QTLs) for key agronomic traits, including plant height, number of primary and secondary branches, number of pods, days to flowering and days to maturity in pigeonpea. Results A population of 186 F2:3 lines derived from an intra-specific cross between inbred lines ‘Pusa Dwarf’ and ‘HDM04-1’ was used to construct a dense molecular linkage map of 296 genic SNP and SSR markers covering a total adjusted map length of 1520.22 cM for the 11 chromosomes of the pigeonpea genome. This is the first dense intra-specific linkage map of pigeonpea with the highest genome length coverage. Phenotypic data from the F2:3 families were used to identify thirteen QTLs for the six agronomic traits. The proportion of phenotypic variance explained by the individual QTLs ranged from 3.18% to 51.4%. Ten of these QTLs were clustered in just two genomic regions, indicating pleiotropic effects or close genetic linkage. In addition to the main effects, significant epistatic interaction effects were detected between the QTLs for number of pods per plant. Conclusions A large amount of information on transcript sequences, SSR markers and draft genome sequence is now available for pigeonpea. However, there is need to develop high density linkage maps and identify genes/QTLs for important agronomic traits for practical breeding applications. This is the first report on identification of QTLs for plant type and maturity traits in pigeonpea. The QTLs identified in this study provide a strong foundation for further validation and fine mapping for utilization in the pigeonpea improvement.
Genotype x environment interaction for biometrical traits in pigeonpea (Cajanus cajan L. Millsp.) under varying spacings
H.P. Thanki, S.L. Sawargaonkar and B.V. Hudge
Electronic Journal of Plant Breeding , 2010,
Abstract: Twenty eight genotypes of pigeonpea, which includes promising lines as well as randomly selected varietieswere studied for their G X E interaction. The genotypes were sown in a three different environments were madeavailable by three spacings at 60, 90 and 120 cm. .Pigeonpea genotypes BDN 2001-6, Phule T 11-39, JJ 65, GT 1,BSMR 736 and LRG 41 are considered to be more desirable ones, as they satisfied the criteria suggested by Eberhart andRussell (1966) for stability over three different spacings.
Genetic diversity in pigeonpea [Cajanus cajan (L.) Millsp.] Landraces as revealed by simple sequence repeat markers
S Songok, M Ferguson, AW Muigai, S Silim
African Journal of Biotechnology , 2010,
Abstract: Genetic relationships among 88 pigeonpea accessions from a presumed centre of origin and diversity, India and a presumed secondary centre of diversity in East Africa were evaluated using six microsatellite markers. Forty-seven (47) alleles were detected in the populations studied, with a mean of eight alleles per locus. Populations were defined by region (India and East Africa) and sub-populations by country in the case of East Africa and State in the case of India. Substantial differentiation among regions was evident from Roger’s modified distance and Wright’s F statistic. Greatest genetic diversity in terms of number of alleles, number of rare alleles and Nei’s unbiased estimate of gene diversity (H) was found in India as opposed to East Africa. This supports the hypothesis that India is the centre of diversity and East Africa is a secondary centre of diversity. Within East Africa, germplasm from Tanzania had the highest diversity according to Nei’s unbiased estimate of gene diversity, followed by Kenya and Uganda. Germplasm from Kenya and Tanzania were more closely related than that of Uganda according to Roger’s modified distance. Within India, results did not indicate a clear centre of diversity. Values of genetic distance indicated that genetic relationships followed geographical proximity.
Genetic Diversity of Pigeonpea (Cajanus cajan (L.) Millsp.) Cultivars and Its Wild Relatives Using Randomly Amplified Polymorphic DNA (RAPD) Markers  [PDF]
Kusum Yadav, Sanjay Kumar Yadav, Anurag Yadav, Veda Prakash Pandey, Upendra Nath Dwivedi
American Journal of Plant Sciences (AJPS) , 2012, DOI: 10.4236/ajps.2012.33038
Abstract: Genetic diversity among and between 16 cultivars of pigeonpea (Cajanus cajan (L) Millsp.) and its wild relatives (C. albicans and C. lineatus) analysed using RAPD. Twenty two random primers with an average of 71.2% polymorphism produced 151 polymorphic bands. Cluster analysis based on these 151 RAPD markers revealed relatively low level (0.434 - 0.714) of genetic diversity among cultivars and high level of diversity between cultivars and wild relatives. C. albicans and C. lineatus showed only 0.231 similarity with each other and C. albicans showed relatively higher similarity with C. cajan cultivars than that showed by C. lineatus. In dendrogram the 16 cultivars grouped into two distinct clusters comprising of seven and nine genotypes each while the wild species form out groups. Bootstrap analysis of the dendrogram was performed and resulted in significant bootstrap values. Principal components analysis (PCA) also revealed the similar results that of unweighted pair group method with arithmetic mean (UPGMA). The first, second and third PCs contributed 55.9%, 5.9%, and 5.6% of the variation, respectively, with cumulative variation of the first three PCs was 67.4%.
Page 1 /100
Display every page Item

Copyright © 2008-2017 Open Access Library. All rights reserved.