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The study examined the vegetation composition and phenotypic traits at five sites, differing in degree of disturbance, in a tropical dry deciduous forest of India. A total of 49 species and 4033 individuals (≯= 9.6 cm dbh) were enumerated in the cumulative 15-ha permanently protected area. The study revealed that the five sites represented five more or less different communities (species combinations with different dominants). On the basis of phenotypic traits, these communities or sites could not be discriminated, either by proportion of species belonging to different trait categories or by the cumulative importance value of the trait categories. As a result, disturbance did not affect the predominant traits. Evidently, all the communities shared the major phenotypic traits of the dry deciduous forest. Small leaf size, medium leaf texture, rough bark texture and medium deciduousness characterized the dry deciduous forest vegetation. Both the percent of species and importance values were larger for medium or less deciduous trait categories than for highly deciduous trait, representing a trade-off between water loss and the period of dry matter synthesis.

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The study examined the vegetation composition and phenotypic traits at five sites, differing in degree of disturbance, in a tropical dry deciduous forest of India. A total of 49 species and 4033 individuals (≯= 9.6 cm dbh) were enumerated in the cumulative 15-ha permanently protected area. The study revealed that the five sites represented five more or less different communities (species combinations with different dominants). On the basis of phenotypic traits, these communities or sites could not be discriminated, either by proportion of species belonging to different trait categories or by the cumulative importance value of the trait categories. As a result, disturbance did not affect the predominant traits. Evidently, all the communities shared the major phenotypic traits of the dry deciduous forest. Small leaf size, medium leaf texture, rough bark texture and medium deciduousness characterized the dry deciduous forest vegetation. Both the percent of species and importance values were larger for medium or less deciduous trait categories than for highly deciduous trait, representing a trade-off between water loss and the period of dry matter synthesis.

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One thousand four hundred and eighty three spring wheat germplasm (Triticum aestivum L.) lines comprising Indian as well as exotic lines were screened for resistance to spot blotch disease during winter 2014-15 at hot spot locations i.e., Banaras Hindu University, Varanasi and Uttar Banga Krishi Vishwavidyalaya, Cooch Behar. Severity of the disease at different stages beginning from tillering to dough stage was recorded. Location Severity Index (LSI) of Varanasi was higher than Cooch Behar. Twenty eight accessions were resistant or highly resistant at both locations. These 28 accessions were validated during the winter season (2015–2016). These germplasm were also evaluated at four environments for agronomic traits. Out of 28 accessions, seven (IC564121, IC529684, IC443669, IC443652, IC529962, IC548325 and EC178071-331) were highly resistant across the locations and over the years of study. These accessions comprised one exotic and six indigenous accessions belonging to Uttarakhand and Haryana. Two lines (IC529962 and IC443652) had higher yield than the best check at all the locations. These lines showing highly resistant reaction alongwith wider adaptability can be expedited for direct cultivation or for the development of high yielding and disease resistant cultivars. These lines can also be used for identification of novel resistance gene using allele mining tools and their deployment for the development of spot blotch resistant cultivars.

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Cereal Research Communications
Authors: S. Sareen, R. Munjal, N. Singh, B. Singh, R. Verma, B. Meena, J. Shoran, A. Sarial, and S. Singh

Terminal heat, which is referred as increase in temperature during grain filling, is one of the important stress factors for wheat production. Current estimates indicate that wheat crop grown on around 13.5mha in India is affected by heat stress. In order to meet the challenges of high temperature ahead of global warming, concerted efforts are needed to evaluate germplasm for heat tolerance and identify and develop genotypes suitable for such stressed environments. The advanced wheat genotypes developed for stress and normal environments by different research centers were evaluated across 7 locations representing varied agroclimatic zones during 2007–08 and 2008–09 to study their adaptability for heat stress and non-stress environments. The additive main effects and multiplicative interaction analysis for G × E interactions revealed differences amongst locations to phenology and grain yield. Genotype RAJ 4083 developed for cultivation under late sown conditions in peninsular zone was also found adaptable to timely sown conditions. Similarly, HD 2733 a cultivar of NEPZ timely sown conditions and PBW 574 an advanced breeding line of NWPZ late sown conditions was found adapted to Peninsular zone. The cultivar RAJ 3765 showed specific adaptability to Pantnagar in NWPZ. Genotype NW 3069 developed for NEPZ timely sown conditions have shown adaptability to number of locations; timely sown conditions at Karnal and Hisar in NWPZ and Niphad in PZ. Likewise, WH 1022 developed for NEPZ late sown conditions exhibited specific adaptability to all timely sown locations in NWPZ.

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In order to study the inheritance pattern of morpho-physiological traits in bread wheat, a 10×10 diallel cross, excluding reciprocals was made and grown in a randomized complete block design (RCBD) with three replications. Observations were recorded on Days to 75% flowering (DF), Days to maturity (DM), Duration of reproductive phase (DRP), Plant height (cm) (PH), Effective tiller/plant (TLS), No. of spikelets per spike (SLS), No. of grains per spike (GS), Grain weight per spike (g) (GW), Spike length (cm) (SL), Biological yield per plant (g) (BY), Harvest index (%) (HI), 1000-Grain weight (g) (TGW), Spike density (SD), Canopy temperature depression (°C) (CTD), Chlorophyll intensity (%) (CI), Chlorophyll fluorescence (Fv/Fm) (CF), Protein content (%) (PC), Grain yield per plant (g) (GY). Highly significant differences were observed among the genotypes for all traits. The resulted 45 F1s and their F2s used for study the nature of gene for grain yield and its contributing traits in bread wheat. The result indicated that considerable gene action and average degree of dominance respond to achieving significant result for grain yield and its component traits. In both the generations F1s and F2s, grain yield per plant (g) was governed by non-additive gene action based on combining ability analysis, (σ2 g/σ2 s)0.5 [GCA and SCA variance ratio] and (H1/D)0.5 [Degree of dominance] were exhibited over dominance type average degree of dominance for grain yield and its component traits in both generations. Genetic analyses of the traits confirm the involvement of both additive and non-additive gene effects in governing the inheritance.

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Diploid wheat T. monococcum L. is a model plant for wheat functional genomics. A soft glume mutant was identified during manual screening of EMS-treated M2 progenies of a T. monococcum accession pau14087. The seeds in the mature spike of the mutant could be easily threshed manually. The soft glume mutant with high sterility, tapering and broader spikes had also tougher rachis than the wild type parent. Genetic analysis of crosses of the mutant with wild type indicated that the mutant was monogenic recessive. To map the soft glume mutant, a mapping population was developed by crossing the soft glume mutant with wild Triticum boeoticum acc. pau 5088, having tough glumes and hard threshing. The soft glume mutant was mapped between SSR markers Xgwm473 and Xbarc69 on 7AmL chromosome of T. monococcum, with a genetic distance of 1.8 cM and 8.3 cM, respectively. The soft glum mutant mapped on 7AmL, being distinct from a previously mapped soft glume mutant in wheat, has been designated as sog2. The work on fine mapping of sog2 gene is in progress.

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Wheat cultivation is of great significance in North-western plains of India and the crop was hitherto considered as almost free from serious insect attack. Recently, Pink stem borer (PSB), Sesamia inferens Walker (Lepidoptera: Noctuidae) has emerged as a new pest and is likely to pose serious threat to the successful cultivation of wheat in the North-western plains of India under largely adopted rice-wheat cropping system. Because of the paucity of data on the developmental biology of PSB on wheat crop regarding this emerging problem of insect damage, studies were initiated on biology of PSB under field as well as screenhouse conditions during seasons of 2010–2011 and 2011–2012. This is the first report on biology of PSB on wheat which indicated that the pest was able to survive well/build up populations on wheat and able to complete its life cycle. It laid eggs either at the base of wheat plant near to soil level or on soil-surface or in the left over stubble of rice plants. Eggs hatched within 7.40±0.08 days and the mean larval duration was 68.52±1.55 days. In the course of development, it passed through 8 larval instars and pupation took place near or within the left over rice stubble. Pupal period was 36.05±0.36 days in male while 37.78±0.17 days in female. The survival of adult moths was 5.31±0.26 days in male while 6.61±0.26 days in female. The mean fecundity was 118.38±11.93 eggs and 89.15 per cent of eggs hatched. The total life cycle took 116.92±2.17 and 119.95±2.05 days in males and females, respectively.

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Primary photochemical reactions and the activities of the antioxidant enzymes chloroplastic superoxide dismutase (SOD), glutathione reductase (GR) and glutathione-S-transferase (GST) were determined in water-stressed pearl millet ( Pennisetum glaucum L. cv. HHB-67) plants sprayed with the thiol compounds dithiothreitol (DTT), thioglycolic acid (TGA) and thiourea (TU) and the thiol modifiers 5,5′-dithio-bis-2-nitrobenzoic acid (DTNB) and N-ethylmaleimide (NEM) at the earhead emergence stage (47 days after sowing, DAS), together with a control. Sampling was done at 54 and 67 days after sowing. Photosystem I and II (PS I and II) activities (ferricyanide site) were found to increase in plants sprayed with TU, TGA and DTT at both stages (54 and 67 DAS), but a reduction in PS II activity (DCQ Site) compared with the control was caused by NEM (66.66%) and DTNB (27.77%) at 54 DAS. A similar decrease in the activity of PS II (ferricyanide site) was found at 67 DAS for DTNB (55.55%). The chloroplastic SOD activity increased in chloroplasts isolated from leaves sprayed with thiol compounds at both sampling stages, except for NEM at 54 and 67 DAS. The activities of GR and GST in the leaves were higher in thiol-treated plants than in the control at 54 and 67 DAS, while the lowest GR activity was seen for the sulphydryl modifiers (DTNB and NEM) in leaves at 54 DAS. The experimental data suggest an enhancement in the primary photochemistry and antioxidant enzyme activities of water-stressed pearl millet in response to foliar spraying with thiol compounds.

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Cereal Research Communications
Authors: B. Kumar, K.S. Hooda, R. Gogoi, V. Kumar, S. Kumar, A. Abhishek, P. Bhati, J.C. Sekhar, K.R. Yathish, V. Singh, A. Das, G. Mukri, E. Varghese, H. Kaur, V. Malik, and O.P. Yadav

Maydis leaf blight (MLB), a serious foliar fungal disease of maize, may cause up to 40% losses in yield. The present studies were undertaken to identify the stable sources of MLB resistance, its inheritance study, and testing of MLB resistance linked markers from diverse background in the Indian adapted tropical maize genotypes. A set of 112 inbred lines were screened under artificially created epiphytotics conditions at three hotspot locations. Analysis across multi-locations revealed significant effects of genotypes and environments, and non-significant effects due to genotypes × environment interaction on disease incidence. A total of 25 inbred lines with stable resistance were identified across multi-locations. Inheritance of resistance was studied in six F1s and two F2s of resistant and susceptible parents. The null hypothesis of segregation of resistance and susceptible for mono and digenic ratios in two F2 populations was rejected by Chi-square test. The non-significant differences among the reciprocal crosses depicted the complete control of nuclear genome for MLB resistance. Partial dominance in F1s and normal distribution pattern in F2s of resistant and susceptible parents suggested polygenic nature of MLB resistance. Correlation studies in F2 populations exhibited significant negative correlation between disease score and days to flowering. Five simple sequence repeats (SSRs) markers, found associated to MLB resistance in different studies were unable to differentiate amongst MLB resistance and susceptible parents in our study. This emphasizes the need of fine mapping for MLB resistance in Indian germplasm. The identified stable sources of resistance and information on inheritance study can be used further in strengthening of resistance breeding against MLB.

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