9 research outputs found
Not Available
Not AvailableReniform nematode (Rotylenchulus reniformis) infects castor and makes it vulnerable for vascular wilt and root rot diseases. In this study, a population consisting of 92 recombinant inbred lines (RILs) derived from the cross between reniform nematode resistant line JC-12 and susceptible line 48-1 was used to identify the genomic regions linked to reniform nematode resistance. The parents, F1 and RILs were screened against reniform nematode in pot culture with artificial inoculation of nematodes. The scoring for nematode resistance was done on the basis of number of nematodes extracted from the soil at 60 days after inoculation. The mean nematode count in 48-1 and JC-12 was 215.0 ± 9.1 and 77.8±4.8 nematodes/ml of soil wash, respectively. The F1 reaction (217.3±13.2 nematodes/ml of soil wash) was similar to the susceptible parent indicating that nematode resistance in JC-12 is recessive in nature. The nematode count in RILs ranged from 43.8 to 327.3. QTL mapping using a linkage map consisting of 1,090 SNP markers resulted in the identification one QTL each on chromosome-6 and chromosome-8, linked to resistance. This is the first report on mapping of genomic regions linked to reniform nematode resistance in castor, which form the basis for furthering the research on genetic and molecular biology of nematode resistance in castor.ICA
Not Available
Not AvailableCastor is an industrially important oilseed crop, which provides raw material to many industries. Despite its industrial importance, the genomic resources available for molecular breeding applications are limited. In the present study, a set of 135 SNP loci polymorphic between two castor inbred lines namely, JC-12 and RG-1963 were targeted to develop competitive allele specific PCR assays for genotyping purposes. The assays were validated in the F2 population of JC-12 × RG-1963 cross. Out of 135 assays designed, 124 were found to be successful in discriminating three expected genotypes in the F2 population. Using the SNP genotyping data, a genetic linkage map representing 10 haploid chromosomes of castor was constructed, which corresponded very well with the physical map. This set of validated SNP markers is a useful resource for application in molecular breeding of castor.ICA
Not Available
Not AvailableCastor is a prime industrial crop belonging to a monotypic genus and its genetic improvement
depends on creating desired variability in the primary gene pool. This study reports the development
of tetraploid castor plants through colchicine treatment. Seeds of three castor genotypes
were soaked in aqueous solutions of colchicine with variable concentrations, and the LD50 value
was determined. Of 1010 treated field-raised plants, three were identified as potential polyploids
based on increases in a guard cell size and reductions in the number of stomata. The putative
polyploid plants were selfed and the progeny were subjected to meiotic analysis. All the progeny
were found to be tetraploid. The pairing of chromosomes was abnormal with univalent to octavalent
configurations during meiosis-I, but the later parts of meiosis were normal. Seasonal variations in
pollen fertility indicated the possible role of temperature-sensitive male sterility in causing the
sterility in tetraploid plants. The tetraploid plants were phenotypically comparable with their diploid
counterparts, but produced substantially bigger seeds. Thus, these tetraploid plants are valuable
resources for basic and applied research in castor.ICA
Response surface based optimization of system variables for liquid chromatographic analysis of candesartan cilexetil
A statistical optimization method was successfully employed to study the effect of system variables on the chromatographic analysis of candesartan cilexetil. The effect of simultaneously varying the flow rate, temperature and concentration of acetonitrile in the mobile phase in water (0.05% O-phosphoric acid (0.05% OPA)) was studied to optimize the method to obtain excellent chromatographic responses. The optimum conditions were determined with the help of response surface methodology (RSM) using Plackett–Burman designs. From the response surface graphs, the optimum regions were selected to be −1, +1 and +1 for flow rate (0.8 ml/min), temperature (25 °C) and concentration of acetonitrile in water (0.05% OPA) (80%, v/v), respectively. Pareto ranking indicated that the most important variable affecting the selected responses was temperature. Linearity was found in the range of 10 of 50 μg/ml, with a significantly high correlation coefficient (r2 = 0.9989). The limits of detection and quantitation were 0.12 and 0.33 μg/ml, respectively. The developed method was validated for accuracy, precision, linearity, range, and specificity. The method was successfully used to analyze a tablet formulation to assess the chromatographic performance, and it was found to be 99.03%, with a standard deviation of ±0.04
Not Available
Not AvailableSafflower is grown primarily for edible oil rich in unsaturated fatty acids. Due to higher stability and longer shelf
life, the oil with high oleic acid content is preferred for food and other industrial applications. Safflower cultivars
with high oleic acid content (>70%) have been developed and commercially successful. Incorporation of the high
oleic trait through conventional breeding techniques has been a slow process due to recessive inheritance and
difficulties associated with phenotyping by biochemical methods. DNA based marker-assisted selection (MAS) for
high oleic trait would help speed up the breeding efforts in safflower. In this study, a set of high oleic varieties
were found to carry the same mutation in the fatty acid desaturase 2-1 gene, CtFAD2-1, which is presumed to be
the ‘ol’ allele associated with high oleic acid content in safflower. Genotypic assays namely Kompetitive Allele
Specific PCR (KASP®) and the Amplifluor™ SNPs Genotyping System (Amplifluor®) were designed for the
prediction of high oleic trait based on the mutation in the CtFAD2-1. The assays were thoroughly validated in
segregating populations derived from crosses between low and high oleic parents. Through marker-assisted
backcrossing scheme, the high oleic allele, ‘ol’ from the exotic variety, Montola-2000 was incorporated into
the background of popular Indian linoleic type variety, Bhima and a set of promising high oleic lines (75.2%–
81.8%) were developed. The MAS-derived lines showed consistent expression of high oleic acid content over
seasons and comparable seed/oil yield performance with the local check varieties. The genotypic assays reported
in this study were robust, non-destructive, co-dominant and accurately predicted high oleic trait in segregating
populations; thus, recommended for fast-track breeding of high oleic cultivars in safflowerNot Availabl