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Study of genetic variability and correlation in interspecific derivatives of Pigeonpea [Cajanus cajan (L.) Millsp.]
S.S. Linge , H.V. Kalpande, S.L. Sawargaonkar, B.V. Hudge and H.P. Thanki
Electronic Journal of Plant Breeding , 2010,
Abstract: Forty interspecific derivatives (ISD) of Pigeonpea along with five national checks derived from ICRISAT, Patancheru,Hyderabad and one local check were screened to study the extent of genetic variability for yield and yield contributingcharacter and their interrelationship. The observations were recorded on nineteen different characters. The highest GCV wasrecorded for trichome-A followed by trichome-B. The high heritability estimates coupled with high expected geneticadvance were observed for trichome type-A, B, number of secondary branches, trichome type D, number of pods per plant,grain yield per plant, trichome type C, per cent pod setting, per cent pollen sterility, 100 seed weight, number of primarybranches, height of first primary branch from ground level and seeds per pod indicating the presence of additive gene actionand phenotypic selection may be effective. Grain yield was found to be positively and significantly correlated with allcharacters except for percent pod damage where the association was negative and significant. It indicated that thesecharacters are useful for taking them as the basis of selection for high yield.
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.
Introgression of Helicoverpa armigera Resistance from Cajanus acutifolius-a Wild Relative from Secondary Gene Pool of Pigeon Pea (Cajanus cajan)  [cached]
Deepak R. Jadhav,Nalini Mallikarjuna,Hari C. Sharma,Kulbhushan B. Saxena
Asian Journal of Agricultural Sciences , 2012,
Abstract: The aim of the study was to introgress Helicoverpa armigera resistance from wild relative Cajanus acutifolius into pigeonpea, (Cajanus cajan L.), an important grain legume in South Asia, East Africa and the West Indies. Pigeonpea grain yields on farmer’s fields are quite low, largely because of damage by insect pests, of which legume pod borer Helicoverpa armigera (Hübner) (Lepidoptera: Noctuidae) is the important pest worldwide. Pod borer has developed high levels of resistance to chemical insecticides. Currently, there are no cultivars of pigeonpea with high levels of resistance to H. armigera. Therefore, there is a need to identify and introgress resistance genes from the wild relatives of this crop. Wild relative of pigeonpea, Cajanus acutifolius (ICPW 15613) and the interspecific derivatives C. acutifolius x C. cajan have shown resistance to H. armigera. The results showed that all the test lines and C. acutifolius had high levels of flavonoids such as chlorogenic acid, quercetin and rutin in the flowers and buds, which may have resulted in less damage due to H. armigera larvae. Most of the test lines had more than 15.00 g of seed weight (100 seed weight) and beige seed color. These lines can be used for pigeonpea improvement for resistance to H. armigera.
Anatomy of the Root of Pigeonpea (Cajanus cajan)  [PDF]
Shahanara Begum,A.K.M. Azad-ud-doula Prodhan
Pakistan Journal of Biological Sciences , 2003,
Abstract: Anatomical investigation has been made on the root of pigeonpea (Cajanus cajan (L.) Millsp.) at different stages of growth following the standard paraffin method of microtechnique. The root of pigeonpea is tetrarch with 4 strands of xylem and 4 strands of phloem. One strand of xylem alternates with one strand of phloem. The four opposite strands of primary xylem meet at the centre. Subsequently metaxylem forms near the centre on either side of the xylem strand. Ultimately the centre is filled up with big metaxylem vessels. The epidermis is single layered with root hairs and glandular trichomes. There are 8-13 layers of cortical cells in the root of pigeonpea. The cambium appears in the basal part of the root of 3-4 days old plant. Gradually it extends towards the root apex. The activity of cambium is similar to that of woody dicotyledonous herb. In the mature root, most of the vessels in the secondary xylem are solitary while the others are paired or multiple. The fibre cells in the phloem are arranged in groups. The fibre groups are radially arranged in such a way that the structure seems to be a pyramid. The epidermis is ruptured here and there, and the epidermal cells are disorganized due to the stress of secondary growth. Periderm is formed in the root one after another as the root increases in diameter.
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
Anatomy of the Stem of Pigeonpea (Cajanus cajan)  [PDF]
Shahanara Begum,Md. Azharul Islam,A.K.M. Azad-ud-doula Prodhan
Asian Journal of Plant Sciences , 2007,
Abstract: Anatomical investigation has been made on the stem of pigeonpea (Cajanas cajan (L.) Millsp.) at different stages of growth following the standard paraffin method of microtechnique. The vascular bundle of the stem are collateral and arranged in a ring. The cambium initiates in the primary vascular bundle between xylem and phloem at the basal part of the stem of 3 days old plant. After the formation of fascicular cambium it gives rise to secondary xylem adaxially and secondary phloem abaxially. Most of the vessel members are solitary and few are paired while others are multiple. The solitary vessel members are more in mature stem as compared to that of the younger stem. The well developed periderm was found in mature stem. The pith resembles a typical dicotyledonous stem.
Antimicrobial Activities of Cajanus cajan, Garcinia kola and Xylopia aethiopica on Pathogenic Microorganisms
G.O. Ezeifeka,M.U. Orji,T.I. Mbata,A.O. Patrick
Biotechnology , 2004,
Abstract: The antimicrobial effect of the ethanol and aqueous extracts of locally available plants, Cajanus cajan, Garcinia kola and Xylopia aethiopica on Staphylococcus aureus, Pseudomonas aeruginosa, Escherichia coli and Candida albicans were evaluated. The agar gel diffusion and paper disk diffusion method were used to determine the inhibitory effects of both the leaves and seeds extract of the test plants on the test microorganisms. The plant extracts produced inhibition zones ranging from 3 to 22 mm against the test microorganisms. The ethanol extracts of the test plants were more effective in producing inhibition zones against the micro-organisms than water extracts. The extracts of Cajanus cajan produced wider zones of inhibition against Candida albicans than the other plants extracts.
Shrikant Jain and Sashima Kumari
Bioscience Discovery , 2012,
Abstract: Modern agricultural practices have introduced numerous pesticides, bactericides, insecticides, fungicides, biocides, fertilizers and manures resulting in severe biological and chemical contamination of land. Gradual absorptions of remnants of these pesticides into the soil which may contaminate root crops grown in the soil results in the disruption of the balance of natural cycles and food chains within natural ecosystem. The present study shows the effects of various concentrations of glyphosate, a weedicide widely used by the farmers retard the seed germination percentage and growth of the seedlings in Cajanus cajan(L.). Similarly as the concentration of weedicide increases the gradual decrease in the amylase activity and gibberellin level was observedin C. cajan.
Interspecific hybridization in Pleurotus species  [cached]
Indian Phytopathology , 2012,
Abstract: Interspecific hybridization studies were carried out between P/eurotus sajor-caju, P. sapidus and P. cornucopiae for obtaining better quality strains. The resultant hybrids were categorised on phenotypic basis into two categories. In first group, hybrids obtained were similar in appearance, yield and colour etc. with either of their parents. The second group hybrids had blending of characters of their parents and possessing the yield potential more or less similar to them. A specific hybrid (hybrid no. 3) obtained with mating between P. sajor-caju and P. cornucopiae, in which the shape and size of the sporophore was similar to P. sajor-caju and white colour was resembling with P. cornucopiae. The total average yield of this hybrid was found to be 23.3 per cent more than the parent.
Adaobi C. Ezike,Peter A. Akah,Charles C. Okoli,Chinwe B. Okpala
Journal of Basic and Clinical Pharmacy , 2010,
Abstract: The antidiabetic activity of methanol leaves extract of Cajanus cajan (L.) Millsp.(Fabaceae) was studied in alloxan-diabetic and in oral glucose loaded rats. The acute toxicity and lethality (LD50) and the phytochemical analysis of the extract were also evaluated. The results showed that the extract (400 and 600 mg/kg) significantly (P<0.05) reduced fasting blood sugar of alloxan diabetic rats in a dose-related manner, with maximum hypoglycemic effect at 4 – 6 h. The extract (400 and 600 mg/kg) also significantly (P<0.05) suppressed the peak postprandial rise in blood glucose of normal rats by 101.8 and 57.40 % respectively. Acute toxicity and lethality test of the extract in rats gave an oral LD50 greater than 5 g/kg. The findings indicate that the leaves of C. cajan may be beneficial as an antidiabetic therapy.
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