100 research outputs found
A QTL study on late leaf spot and rust revealed one major QTL for molecular breeding for rust resistance in groundnut (Arachis hypogaea L.)
Late leaf spot (LLS) and rust are two major foliar diseases of groundnut (Arachis hypogaea L.) that often occur together leading to 50–70% yield loss in the crop. A total of 268 recombinant inbred lines of a mapping population TAG 24 × GPBD 4 segregating for LLS and rust were used to undertake quantitative trait locus (QTL) analysis. Phenotyping of the population was carried out under artificial disease epiphytotics. Positive correlations between different stages, high to very high heritability and independent nature of inheritance between both the diseases were observed. Parental genotypes were screened with 1,089 simple sequence repeat (SSR) markers, of which 67 (6.15%) were found polymorphic. Segregation data obtained for these markers facilitated development of partial linkage map (14 linkage groups) with 56 SSR loci. Composite interval mapping (CIM) undertaken on genotyping and phenotyping data yielded 11 QTLs for LLS (explaining 1.70–6.50% phenotypic variation) in three environments and 12 QTLs for rust (explaining 1.70–55.20% phenotypic variation). Interestingly a major QTL associated with rust (QTLrust01), contributing 6.90–55.20% variation, was identified by both CIM and single marker analysis (SMA). A candidate SSR marker (IPAHM 103) linked with this QTL was validated using a wide range of resistant/susceptible breeding lines as well as progeny lines of another mapping population (TG 26 × GPBD 4). Therefore, this marker should be useful for introgressing the major QTL for rust in desired lines/varieties of groundnut through marker-assisted backcrossing
Identification of several small main-effect QTLs and a large number of epistatic QTLs for drought tolerance related traits in groundnut (Arachishypogaea L.)
Cultivated groundnut or peanut (Arachis hypogaea L.), an allotetraploid (2n = 4x = 40), is a self pollinated and widely grown crop in the semi-arid regions of the world. Improvement of drought tolerance is an important area of research for groundnut breeding programmes. Therefore, for the identification of candidate QTLs for drought tolerance, a comprehensive and refined genetic map containing 191 SSR loci based on a single mapping population (TAG 24 × ICGV 86031), segregating for drought and surrogate traits was developed. Genotyping data and phenotyping data collected for more than ten drought related traits in 2–3 seasons were analyzed in detail for identification of main effect QTLs (M-QTLs) and epistatic QTLs (E-QTLs) using QTL Cartographer, QTLNetwork and Genotype Matrix Mapping (GMM) programmes. A total of 105 M-QTLs with 3.48–33.36% phenotypic variation explained (PVE) were identified using QTL Cartographer, while only 65 M-QTLs with 1.3–15.01% PVE were identified using QTLNetwork. A total of 53 M-QTLs were such which were identified using both programmes. On the other hand, GMM identified 186 (8.54–44.72% PVE) and 63 (7.11–21.13% PVE), three and two loci interactions, whereas only 8 E-QTL interactions with 1.7–8.34% PVE were identified through QTLNetwork. Interestingly a number of co-localized QTLs controlling 2–9 traits were also identified. The identification of few major, many minor M-QTLs and QTL × QTL interactions during the present study confirmed the complex and quantitative nature of drought tolerance in groundnut. This study suggests deployment of modern approaches like marker-assisted recurrent selection or genomic selection instead of marker-assisted backcrossing approach for breeding for drought tolerance in groundnut
Micro-algae come of age as a platform for recombinant protein production
A complete set of genetic tools is still being developed for the micro-alga Chlamydomonas reinhardtii. Yet even with this incomplete set, this photosynthetic single-celled plant has demonstrated significant promise as a platform for recombinant protein expression. In recent years, techniques have been developed that allow for robust expression of genes from both the nuclear and plastid genome. With these advances, many research groups have examined the pliability of this and other micro-algae as biological machines capable of producing recombinant peptides and proteins. This review describes recent successes in recombinant protein production in Chlamydomonas, including production of complex mammalian therapeutic proteins and monoclonal antibodies at levels sufficient for production at economic parity with existing production platforms. These advances have also shed light on the details of algal protein production at the molecular level, and provide insight into the next steps for optimizing micro-algae as a useful platform for the production of therapeutic and industrially relevant recombinant proteins
New early-maturing germplasm lines for utilization in chickpea improvement
Early-maturity helps chickpea to avoid terminal heat and drought and increases its adaptation especially in the sub-tropics. Breeding for early-maturing, high-yielding and broad-based cultivars requires diverse sources of early-maturity. Twenty-eight early-maturing chickpea germplasm lines representing wide geographical diversity were identified using core collection approach and evaluated with four control cultivars in five environments for 7 qualitative and 16 quantitative traits at ICRISAT Centre, Patancheru, India. Significant genotypic variance was observed for days to flowering and maturity in all the environments indicating scope for selection. Genotypes × environment interactions were significant for days to flowering and maturity and eight other agronomic traits. ICC 16641, ICC 16644, ICC 11040, ICC 11180, and ICC 12424 were very early-maturing, similar to or earlier than control cultivars Harigantars and ICCV 2. The early-maturing accessions produced on average 22.8% more seed yield than the mean of four control cultivars in the test environments. ICC 14648, ICC 16641 and ICC 16644 had higher 100-seed weight than control cultivars, Annigeri and ICCV 2. Cluster analysis delineated three clusters, which differed significantly for all the traits. First cluster comprised three controls, ICCV 96029, Harigantars, ICCV 2 and two germplasm lines, ICC 16644 and ICC 16641, second cluster comprised 13 germplasm lines and control cultivar Annigeri, and third cluster comprised 13 germplasm lines. Maturity was main basis of delineation of the first cluster from others. Plot yield and its associated traits were the main basis for delineation of the second cluster
Standardizing the experimental conditions for using urine in NMR-based metabolomic studies with a particular focus on diagnostic studies: a review
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Not AvailableTo assess the effect of inclusion of sun-dried sugarcane press residue (SPR) at different levels on the growth performance and carcass characteristics of broilers, day-old straight-run commercial broiler chicks (n=360) were assigned to twelve dietary treatments. Three iso-nitorgenous and iso-caloric experimental diets containing 0, 5 and 10 per cent SPR replacing the relevant organic nutrients and mineral sources were formulated. Further, each diet was fortified with supplements viz., lipid utilizing agents (lipase 0.2 g + soy lecithin @ 2g/kg) or NSP degrading enzymes @ 0.4g /kg or together to result in another 8 test diets. Each diet prepared for starter (0-14 days), grower (15-28 days) and finisher (29-42days) phases was offered to triplicate groups of 10 chicks each. The results revealed a significantly (P<0.01) lower body weight gain during all the phases and cumulatively, less feed consumption during starter phase and poor feed conversion ratio during starter and finisher phase with the incremental level of SPR. The net returns, performance index and economic index scores were significantly (P<0.05) lower at higher level of SPR inclusion. The main factor, SPR level (0, 5 and 10%), showed significant (P < 0.01) differences for all the growth performance parameters while the biotechnological supplements showed non-significant differences among different groups. The inclusion of SPR beyond 5 per cent in broiler diets is not economically feasible and none of the biotechnological approaches used in this study proved to be effective in improving the nutritive value of SPR.Not Availabl
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Not AvailableBackground: Maize (Zea mays) grain sprouts (MGS) can be a potential source of green fodder for ruminants, especially when there is scarcity of land and water. Nutritional value of MGS grown with hydroponic technique was assessed for nutrient utilization, blood biochemical profile, immunity and growth performance in lambs.
Methods: The MGS were produced in a polyhouse and harvested on 10th day and subjected to rumen in vitro incubation for gas production (RIVIGP) test to predict metabolisable energy (ME) value. The feeding cum growth trial was conducted for 120 days. Eighteen healthy male lambs of 3-4 months age and comparable body weight were randomly allotted in a complete randomized design to three dietary groups of six in each. The control (T1) group lambs were fed conventional green fodder (CGF), finger millet straw (FMS) and compounded feed mixture (CFM) at 50:10:40 ratio on DM basis, In treatment group two (T2), proportion of CGF and CFM was reduced by 50% and substituted with 45% MGS on DM basis (CGF, FMS, CFM and MGS on total DM basis was in 25:10:20:45 ratio, respectively). In treatment group three (T3), CGF was completely replaced with MGS (80%) and CFM was reduced to 25% of control (CGF, FMS, CFM and MGS on total DM basis was in 0:10:10:80 ratio, respectively).
Result: Results indicated that MGS has ME (MJ/kg DM) of 9.70. The average DM intake (g/d/lamb) in T1, T2 and T3 groups was 764, 581 and 398, respectively. The average daily gain (ADG, g) in T1, T2 and T3 groups was 77.3, 48.5 and 20.9, respectively. There was a significant (P<0.05) decrease in DMI and ADG with reduced feed efficiency in lambs fed MGS. However, the per cent digestibility of nutrients, blood biochemical profile, immunity and serum minerals in lambs did not differ among the groups. It is concluded that replacement of compounded feed mixture or conventional green fodder with MGS will limit the dry matter intake, net nutrient availability and negatively affect the growth performance in lambs.Not Availabl
Effect of Fiber Volume on Mechanical Properties of Alkaline Treated Unidirectional Long Kenaf Fiber with Egg Shell Powder Reinforced Polymer Matrix Composite
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