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21.
The immunological response of the Ln subiliacus (externus) in cattle bearing ethmoid carcinoma was studied. The lymph node was stimulated in vivo by I/D administration of tumour antigen and Bacillus Calmette-Guerin and the changes in the lymph node were studied at 3-day intervals up to 15 days. The histological changes in the lymph node were assessed and the functional activity of the activated macrophages in the lymph node impression smears was evaluated using Nitroblue tetrazolium salt reduction test. Similar studies were also undertaken in age-matched healthy nontumour bearing cattle. On stimulation with BCG and tumour antigen there was stimulation of the T cell dependent area. However, the response to the tumour antigen was quicker but shorter in duration compared with that to BCG. The response in healthy animals was proportionately much less. The studies indicated that tumour-bearing animals which were mostly in stage II were immunocompetent. 相似文献
22.
Ramakrishnappa Archana Kunnummal Kurungara Vinod Subbaiyan Gopala Krishnan Elangovan Devi Chandra Vadhana Prolay Kumar Bhowmick Vikram Jeet Singh Ranjith Kumar Ellur Lekshmy Sathee Pranab Kumar Mandal Haritha Bollinedi Shekharappa Nanda Kumar Sonu Mariappan Nagarajan Ashok Kumar Singh 《Plant Breeding》2023,142(3):312-326
Functional stay-green (FSG) is characterized by delayed senescence during the reproductive stage in rice. A recombinant inbred line (RIL) population derived from ‘Pusa 677’/‘PSG16’ was used to study the genetics of FSG in a rice mutant, ‘PSG16’. The RILs exhibited significant variation under two N regimes for agro-morphological traits, leaf chlorophyll content, flowering time, yield components and nitrogen (N) use. Using a genome wide linkage map spanning 1910.8 cM with 104 polymorphic markers, we have mapped six major quantitative trait loci (QTLs). One robust QTL on chromosome 1 was associated consistently across different N regimes with chlorophyll content and flowering time. The QTL on chromosome 7 was associated with grain number, whereas the QTL on chromosome 6 was found related to N harvest index and spikelet fertility. Although ‘PSG16’ showed a clear advantage in grain yield as well as having better N assimilation, we could not establish a direct genetic relationship SG trait and N use. Based on the QTL information, FSG trait of ‘PSG16’ could be useful in deciphering multiple stress responses in rice. 相似文献
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Shivakumar Shidenur Vikram Jeet Singh Kunnummal Kurungara Vinod S Gopala Krishnan Surendra Kumar Ghritlahre Haritha Bollinedi Brijesh Kumar Dixit Ranjith Kumar Ellur Mariappan Nagarajan Ashok Kumar Singh Prolay Kumar Bhowmick 《Plant Breeding》2020,139(4):743-753
Thirty-one tropical japonica derived Rf gene carrying rice hybrids were classified into three classes as Rf3, Rf4 and Rf3 + Rf4 hybrids. These hybrids were tested under three different mega-environments. Between Rf3 class and both the classes of hybrids possessing Rf4 genes, significant variation for spikelet and pollen fertility and grain yield was found. The pollen fertility was five times higher among Rf4 hybrids than that of hybrids carrying Rf3 alone. Likewise, spikelet fertility among Rf4 hybrids was two times higher than that of Rf3 hybrids. Parallel grain yield increase in Rf4 hybrids was 2.4 times than in Rf3 hybrids. However, Rf3 gene was found complementing Rf4 to truncate the range of pollen and spikelet fertility. Hybrids possessing Rf3 alone exhibited partial pollen and spikelet sterility, and significant negative standard heterosis for grain yield. The high yielding hybrid, “HYB36” carrying both the Rf genes was found to be widely adapted. The present study established that Rf4 gene is essential either alone or in combination with Rf3 for fertility restoration to achieve enhanced grain yield in WA-CMS based hybrids. 相似文献
24.
Shivakumar Shidenur Vikram Jeet Singh Kunnummal Kurungara Vinod Subbaiyan Gopala Krishnan Surendra Kumar Ghritlahre Haritha Bollinedi Ranjith K. Ellur Brijesh Kumar Dixit Binder Singh Mariappan Nagarajan Ashok Kumar Singh Prolay Kumar Bhowmick 《Plant Breeding》2019,138(5):553-567
Hybrid rice based on wild‐abortive cytoplasmic male sterility (WA‐CMS) is important in boosting rice production, which requires diverse parents to harness heterosis. For this, exploiting the diversity of japonica through tropical japonica (TRJ) lines is an excellent route. In this study, 310 TRJ‐based new plant type (NPT) lines were developed and evaluated for Rf3 and Rf4 genes. Gene‐based (DRRM‐Rf3‐5 and DRRM‐Rf3‐10) and functional marker (RMS‐SF21‐5) targeted Rf3 locus, while gene‐linked (RM6100) and functional marker (RMS‐PPR9‐1) targeted the Rf4 locus. The frequency of the restorer allele of Rf3 gene was lower when compared to that of Rf4. Combined phenotypic and molecular screening using gene‐based and functional markers identified 42 lines that carried Rf3 and/or Rf4 genes. All the selected lines produced fertile F1s when crossed to a WA‐CMS line, “Pusa 6A”, but with varying levels of spikelet fertility. This is the first report of a marker‐cum‐phenotype‐based restorer selection using TRJ‐derived lines. Multilocation evaluation of these lines at three locations indicated better adaptation for grain yield in some of the lines. 相似文献
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26.
Sandeep Kumar U. N. Joshi Vikram Singh J. V. Singh M. L. Saini 《Genetic Resources and Crop Evolution》2013,60(7):2017-2032
Twenty-three released and elite genotypes of guar [Cyamopsis tetragonoloba (L.) Taub.] from different parts of India were subjected to morphological, biochemical and molecular characterization. The major objective was to study the extent of genetic variability amongst different genotypes of guar, their grouping and identification using combination of phenotypic, biochemical and molecular markers. Phenotypic characters revealed the presence of ample amount of variation in cotyledon size, root length, hypocotyl length, epicotyl length, pubescence, plant height, leaf margin, branching habit, growth habit, days to 50 % flowering, days to maturity, flower colour, pod size, number of pods per cluster and number of clusters per plant for all the 23 genotypes. Biochemical studies including peroxidase activity along with phenol, potassium hydroxide and gibberellic acid tests also produced significant variability among the genotypes. A total of 180 amplified bands were detected using 21 RAPD primers, out of which 178 were polymorphic. The genotypes revealed high genetic divergence with similarity indices ranged from 0.59 to 0.85. A clear relationship between genetic diversity and geographical location was not observed. Fingerprints generated in the present study, using morphological, biochemical and molecular markers, successfully categorize the different guar genotypes into various groups and also establish relatedness among them based on the genetic diversity. This work will help the breeders working in the country for crop improvement of guar in characterization, identification, determination of seed purity and parental selection. 相似文献
27.
Volatile metabolite profiling to detect and discriminate stem-end rot and anthracnose diseases of mango fruits 总被引：2，自引：0，他引：2
The volatile metabolites from the headspace gas of containerised mango ( Mangifera indica ) cv. Tommy Atkins fruits, surface wounded and inoculated with the two fungal anamorphic pathogens Colletotrichum gloeosporioides and Lasiodiplodia theobromae , or non-inoculated (controls), were profiled using a portable gas chromatograph/mass spectrometer to discriminate diseases of mango. Thirty-four compounds were detected relatively consistently among replicates. Several of these were disease/inoculation-discriminatory and were classified into three groups: (i) compounds unique to only one treatment; (ii) compounds common to two or more treatments, but not to all; and (iii) compounds common to all treatments, but varying in their abundance. Two compounds, 1-pentanol and ethyl boronate, were detected in L. theobromae- inoculated mangoes alone, while thujol was observed only in C. gloeosporioides- inoculated mangoes. Discriminant analysis models based on the abundance of significant mass ions and consistent compounds correctly classified diseases/inoculations in up to 100% of cases. The disease-discriminatory compounds and discriminant analysis models developed here have the potential to be used in the early detection of postharvest diseases of mango fruits after validation under commercial conditions. 相似文献
28.
Magnetic resonance imaging (MRI) can elucidate the interior structure of an optically opaque object in unparalleled detail but is ultimately limited by the need to enclose the object within a detection coil; acquiring the image with increasingly smaller pixels reduces the sensitivity, because each pixel occupies a proportionately smaller fraction of the detector's volume. We developed a technique that overcomes this limitation by means of remotely detected MRI. Images of fluids flowing in channel assemblies are encoded into the phase and intensity of the constituent molecules' nuclear magnetic resonance signals and then decoded by a volume-matched detector after the fluids flow out of the sample. In combination with compressive sampling, we thus obtain microscopic images of flow and velocity distributions ~10(6) times faster than is possible with conventional MRI on this hardware. Our results illustrate the facile integration of MRI with microfluidic assays and suggest generalizations to other systems involving microscopic flow. 相似文献
29.
Vikram S. Bisht Piara S. Bains James R. Letal 《American Journal of Potato Research》1993,70(8):611-616
Limited development of blackleg resistant potato cultivars has been ascribed to the lack of an effective and reliable test for large scale blackleg resistance screening. A method using leaf petioles was developed for assessing susceptibility of potato stems to blackleg pathogens (Erwinia carotovora subspeciesatroseptica andE. c. subspeciescarotovora). Fifty grams of sterile autoclaved silica sand in Magenta jars (GA-7 vessel, Magenta Corp., Chicago, Illinois) was drenched with bacterial suspension, (17 ml, 2.6 × 10 to 2.6 × 107 cfu/ml) and freshly cut petioles from 5 to 6 week-old plants were inserted to about 5 mm into the sand. The Magenta jars with lids closed were kept on a laboratory bench (20 ±2 C, 16 hours light). The arrangement provided near ideal post-inoculation incubation environment of high humidity for pathogen multiplication and rot development in the petioles. Length of rot was recorded 72 hours after inoculation. Linear regression of rot development on inoculum concentration had R2 ≥ 0.80. The petioles inoculated and incubated by this method produced measurable rot lesions with a bacterial concentration as low as 2.6 × 104 cfu/ml and differentiated between the resistant cultivar Russet Burbank and the susceptible cultivar Sangre at all the inoculum concentrations used. Furthermore, susceptibility ranking of five cultivars obtained by this method agreed in general with their reported field reactions. The method is simple and sensitive, and could be used for large scale screening for stem rot resistance in wildSolanum species and early generation breeding populations. 相似文献