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21.
Nirmala Sehrawat Mukesh Yadav Anil Kumar Sharma Vikas Kumar Kangila Venkataraman Bhat 《Archives of Agronomy and Soil Science》2019,65(9):1287-1301
Mungbean is an important food grain legume with high economic status. It has an excellent source of dietary protein and nutritional health benefits, particularly for the vegetarians. It increases soil fertility and also plays an imperative role in major cropping systems due to its short life span. Production of mungbean is still decreasing due to its susceptibility towards various environmental stress factors. Salt stress is one of the most prevailing abiotic stress imposing threats for agriculture food crops along with increasing world population and limited natural resources. Fewer efforts have been made to develop an improved variety of mungbean. The present review summarizes the adverse effects of salt stress and mungbean response at the physiological and molecular level. It covers recent studies on introgression of useful traits in mungbean for its better adaptability and survival under stressed conditions. Modern biotechnological approaches and traditional breeding methods may assist the development of salt-tolerant cultivars of mungbean for salinity-affected area in arid and semi-arid regions. Researchers involved in this area should keep this goal on priority for sustainable mungbean production. Availability of protein-rich food may help to reduce the problem of malnutrition in poor families and national food security issue for a continuous rising population. 相似文献
22.
Julie Bitz-Thorsen Katja Häkli Shripathi Bhat Kim Præbel 《Ecology of Freshwater Fish》2020,29(1):40-49
In northern Fennoscandian lakes, monophylogenetic lineages of postglacial fishes are radiating into several adaptive forms, but the speciation process is still at an incipient stage. The speciation process has received increased attention over the years, but the underlying mechanisms and drivers are still debated and poorly understood. European whitefish (Coregonus lavaretus [L.]) is the most abundant fish species in these lakes and has evolved into several ecomorphs adapted to different trophic niches and habitats. Genetic divergence has been observed among these ecomorphs, but the mechanism(s) responsible for the ongoing build-up of reproductive isolation has still to be revealed. As these systems are young in evolutionary time (<10 kyr), prezygotic and postzygotic extrinsic isolation mechanisms are thought to be more likely to contribute to the reproductive isolation than intrinsic isolation mechanisms. We determined the gonadosomatic index (GSI) of three ecomorphs in two replicated lake systems and used GSI as a proxy to investigate the prezygotic isolation mechanism, allochrony, as a driving factor of divergence in this adaptive radiation of whitefish. We found that the three ecomorphs differed in GSI values within and between lakes, suggesting different spawning times of the ecomorphs. We also show that males of one ecomorph had equal onset of maturity as another ecomorph, giving novel insights into the ongoing gene flow observed between ecomorphs. The result supports allochrony as a driver for the divergence process of whitefish ecomorphs, but more evidence is still needed to rule out that the three ecomorphs make use of different spawning grounds. 相似文献
23.
Mohd. Iqbal Yatoo Oveas Raffiq Parray Shah Tauseef Bashir Muheet Riyaz Ahmed Bhat Arumugam Gopalakrishnan 《The Veterinary quarterly》2019,39(1):1-25
Contagious caprine pleuropneumonia (CCPP) is a serious disease of goats, occasionally sheep and wild ruminants, caused by Mycoplasma capricolum subspecies capripneumoniae (Mccp). The disease is characterized by severe serofibrinous pleuropneumonia, very high morbidity (~100%), and mortality (80–100%). CCPP affects goats in more than 40 countries of the world thereby posing a serious threat to goat farming around the globe. The characteristic clinical signs of CCPP are severe respiratory distress associated with sero-mucoid nasal discharge, coughing, dyspnea, pyrexia, pleurodynia, and general malaise. In later stages, severe lobar fibrinous pleuropneumonia, profuse fluid accumulation in pleural cavity, severe congestion of lungs and adhesion formation is observed. Mycoplasmal antigen interactions with host immune system and its role in CCPP pathogenesis are not clearly understood. CCPP is not a zoonotic disease. Diagnosis has overcome cumbersome and lengthy conventional tests involving culture, isolation, and identification by advanced serological (LAT, cELISA) or gene-based amplification of DNA (PCR, RFLP, and hybridization) and sequencing. The latex agglutination test (LAT) is rapid, simple, and better test for field and real-time diagnosis applicable to whole blood or serum and is more sensitive than the CFT and easier than the cELISA. Moreover, the studies on antibiotic sensitivity and exploration of novel antibiotics (fluoroquinolones, macrolides) can help in better therapeutic management besides preventing menace of antibiotic resistance. Re-visiting conventional prophylactic measures focussing on developing novel strain-based or recombinant vaccines using specific antigens (capsular or cellular) should be the most important strategy for controlling the disease worldwide. 相似文献
24.
Yatoo Mohd. Iqbal Parray Oveas Raffiq Mir Muheet Bhat Riyaz Ahmed Malik Hamid Ullah Fazili Mujeeb ur Rehman Qureshi Sabia Mir Masood Salim Yousuf Raja Wasim Tufani Noor Alam Dhama Kuldeep Bashir Shah Tauseef 《Tropical animal health and production》2019,51(8):2127-2137
Tropical Animal Health and Production - Therapeutic management of contagious caprine pleuroneumonia (CCPP) involves mostly the use of oxytetracycline followed by enrofloxacin and rarely tylosin. In... 相似文献
25.
Vipin Kumar Shailendra Sharma Shubham Kero Shiveta Sharma Amit K. Sharma Mukesh Kumar K. Venkataramana Bhat 《Scientia Horticulturae》2008
AFLP technique was applied to assess genetic diversity among 44 common bean accessions that included 6 exotic accessions, 15 Indian land races and 23 released varieties. Eight AFLP primer pairs were used that produced 820 products of which 698 were polymorphic (85.12%). Wide variations were observed among all the accessions for the number of amplification products, percent polymorphism and average polymorphism information content (PIC). The Jaccard's similarity indices (J) based on the AFLP profiles were subjected to UPGMA cluster analysis. The dendrogram generated revealed seven major groups. Seventeen out of 23 released varieties were restricted to clusters VI and VII. The value of r = 0.934 in Mantel's test for cophenetic corrlelation applied to the cluster analysis indicated the high fitness of the accessions to a group. The germplasm used in the present study had narrow genetic base, although moderate to high genetic diversity was observed. The details of diversity analysis and the potential use of Indian common bean accessions in common bean breeding programme are provided in the present study. 相似文献
26.
Study of genetic diversity in Indian and exotic sesame (Sesamum indicum L.) germplasm using random amplified polymorphic DNA (RAPD) markers 总被引:1,自引:0,他引:1
Fifty-eight accessions of sesame (Sesamum indicum L.), an important oil seed crop of the tropics and subtropics were analysed using random amplified polymorphic DNA (RAPD)
technique. The material analysed comprised 36 collections from 18 different states of India and four adjoining countries of
the Indian subcontinent, and 22 exotic accessions from 21 sesame growing countries around the world. The results from PCR
amplifications with the selected 24 random 10-mer primers were statistically analysed. The value of Jaccard’s similarity coefficients
ranged from 0.19 to 0.89. The results indicated the presence of high level of genetic diversity. However, the extent of genetic
diversity was greater in the collections from Indian subcontinent as compared to the exotics. Among the Indian accessions,
the collections from Rajasthan and North-eastern states were highly diverse. The phenetic analysis grouped 48 out of 58 accessions
in six clusters and the remaining highly diverse accessions were placed outside these close-knit clusters. The Bootstrap estimates
obtained by Wagner parsimony analysis were significant for seven out of 49 nodes in the majority-rule consensus tree (<95%
occurrence). The results of both the analyses were, however, broadly comparable when the constitution of the individual clusters
were considered. The principal components analysis indicated that the first two components accounted for only 21% of the total
variations and in order to explain <75% of variations 18 components were required. The high level of genetic diversity prevalent
among the Indian collections is probably indicative of the nativity of this crop species. Similarly, the relatively lower
level of polymorphism in exotic germplasm could be ascribed to the comparatively recent introductions of limited germplasm
of this crop into some of the non-traditional sesame growing countries.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
27.
Murali Haran K. Sham Bhat Julio Molineros Erick De Wolf 《Journal of Agricultural, Biological & Environmental Statistics》2010,15(2):158-175
Fusarium Head Blight (FHB), or “scab,” is a very destructive disease that affects wheat crops. Recent research has resulted
in accurate weather-driven models that estimate the probability of an FHB epidemic based on experiments. However, these predictions
ignore two crucial aspects of FHB epidemics: (1) An epidemic is very unlikely to occur unless the plants are flowering, and
(2) FHB spreads by its spores, resulting in spatial and temporal dependence in risk. We develop a new approach that combines
existing weather-based probabilities with information on flowering dates from survey data, while simultaneously accounting
for spatial and temporal dependence. Our model combines two space-time processes, one associated with pure weather-based FHB
risks and the other associated with flowering date probabilities. To allow for scalability, we model spatiotemporal dependence
via a process convolutions approach. Our sample-based approach produces a realistic assessment of areas that are persistently
at high risk (where the probability of an epidemic is elevated for extended time periods), along with associated estimates
of uncertainty. We conclude with the application of our approach to a case study from North Dakota. 相似文献
28.
Log Characteristics and Sawn Timber Recovery of Home-Garden Teak from Wet and Dry Localities of Kerala, India 总被引:1,自引:1,他引:0
There is a widely held view among smallholders that teak timber produced from small-scale agroforestry systems, especially
home-garden forestry, fetches a lower price than that from conventional plantation forestry. To examine the veracity of this
view, the wood quality attributes of teak from two home gardens in the district of Ernakulam (wet site) and Palakkad (dry
site) in India were compared to those of forest plantation in Nilambur. The logs were graded using standard timber trade practices
into high, medium and low quality as determined by the potential sawn timber grade-yield recovery pattern. Of 96 home garden
teak logs (aged 35 years) from wet and dry sites, 59% belonged to timber Grade II–IV and the rest were classified as poles.
Grade I logs (export quality) with a girth above 150 cm were not available from either of the homesteads. Faster-grown teak
in the wet site produced large diameter logs (dbh 1.37 m) with average diameter of 39.6 cm, which is comparable to that of
best site quality in India. In contrast, the average dbh for teak grown in the dry site was 24 cm as compared to the average
dbh of 31 cm recorded from the same aged forest plantation in Nilambur. It was found that only 10% of logs belonged to Grade
II timber and the rest fell under grades III and IV with more frequent visual defects. The sawn timber recovery percentage
was lower for the dry site (66.8%), whereas there was no significant difference in grade from the wet and forest plantation
sites, with recovery rates of 76.5% and 78.8%, respectively. The general notion that home garden teak has a large proportion
of sapwood seems to be baseless, no significant difference being found between the heartwood-sapwood ratio of home-garden
and forest plantation teak. Lack of appropriate silvicultural practices in home-garden forestry caused the production of more
defective logs, adversely affecting the market price of timber.
相似文献
Puthenpurayil Kumaran ThulasidasEmail: |
29.
Vipin Kumar Shailendra Sharma Amit Kumar Sharma Shiveta Sharma K. Venkataramana Bhat 《Euphytica》2009,170(3):249-262
Morpho-agronomic traits and microsatellite markers were used to survey genetic diversity in 115 common bean genotypes that
included 70 Indian landraces, 24 released varieties and 21 exotic accessions. Twelve morpho-agronomic traits, namely, days
to 50% flowering, leaflet length, leaflet width, pod length, pod width, number of pods per plant, days to maturity, seed length,
seed width, number of seeds per pod, 100 seed weight and seed yield per plant were studied. Field data of two consecutive
years were subjected to multivariate analysis as proposed by Mahalanobis’s D2-statistics, Tochers method of clustering and combined analysis of variance. Seventeen microsatellite markers were also used
to examine genetic diversity at molecular level that showed polymorphic information content (PIC) in the range of 0.00–0.684.
Dendrograms based on Euclidean distances and UPGMA analysis showed the presence of majority of released varieties into single
cluster, which pointed toward their low genetic base in comparison to indigenous landraces and exotic germplasm. Significant
correlation existed between morphological genetic distance and microsatellite genetic distance tested by Mantel test (r = 0.876). 相似文献
30.
Validated protocols for DNA purification and PCR amplification are reported for detection of Phytophthora cactorum in diseased strawberry plants. To remove PCR inhibitors, necrotic strawberry tissues were soaked in 5% alconox solution for >12 h before DNA extraction, and the extracted genomic DNA was embedded in an agarose gel chamber and subjected to electrophoresis. The purified DNA was amplified reliably by PCR. Nested PCR was used to detect a portion of the rRNA gene of P. cactorum in samples. In the first round of PCR, primers ITS1 and ITS4 amplified fragments of varying sizes from total genomic DNA from diseased strawberry plants. In the second round of PCR, a 1:25 dilution of the first-round PCR products was used as template with two P. cactorum- specific primer pairs (BPhycacL87FRG and BPhycacR87RRG, which amplified a 340-bp fragment and a 480-bp fragment from the rRNA gene; and BPhycacL89FRG and BPhycacR176RRG, which amplified a 431-bp fragment). Validation tests using culture-based isolations as a standard for comparison indicated that the DNA purification and PCR primers and amplification protocols were reliable and specifically amplified a portion of the rRNA gene of P. cactorum from necrotic root, crown and petiole tissues of strawberry naturally infected by the pathogen. 相似文献