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91.
Ravi Ranjan Rakesh Kumar Singh Thirupathi Yasotha Manish Kumar Kuldeep Kumar Renu Singh Monzamul Houque Vijay Prakash Mourya Gyanendra Singh Mihir Sarkar Bikash Chandra Das Sadhan Bag 《In vitro cellular & developmental biology. Animal》2013,49(7):486-491
The present study was conducted to see the in vivo developmental potency of caprine parthenogenetic embryos generated in a modified way. The good quality caprine oocytes were matured in presence of cytochalasin B (CCB) and then activated by 7% ethanol followed by 2 mM 6-dimethyl amino purine (6-DMAP) and embryo development was recorded. Early stage parthenogenetic embryos (two to four cells) were surgically transferred in recipients (10). The pregnancy diagnosis was done by nonreturn to oestrus, ultrasonography (USG), and progesterone estimation. The levels of progesterone were above normal values (1 ng/ml) of pregnancy and fall below the level of pregnancy just before retuned to oestrus. Progesterone profile revealed that out of ten recipients (G1–G10), four goats (G1, G2, G3, and G5) returned to oestrus after 43?±?7.29 (Mean?±?SE) d of embryo transfer and six goats (G4, G6, G7, G8, G9, and G10) did not return to cycle even after 70 d of embryo transfer. In three recipients (G4, G5, and G6), the USG on day 40 revealed that there was fluid filled uterine body with solid fetus-like structure. These might be dead fetus and had started resorption. The progesterone profile also corroborated the assumption of pregnancy in these animals. Authors believe that this may be the first report on in vivo diploid parthenogenetic embryo development in caprine species. 相似文献
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93.
Litter decay is a significant part of carbon budget. Due to strong environmental control, the changes in the environment may drastically influence the litter decay rates. Litter decomposition of eight dry tropical woody species, viz. Shorea robusta, Buchanania lanzan, Diospyros melanoxylon, Lagerstroemia parviflora, Lannea coromandelica, Terminalia tomentosa, Holarrhena antidysenterica and Lantana camara was studied to document the effect of intra-annual changes in the environment. Litter decomposition was monitored at monthly intervals at five sites using litter bag technique over an annual cycle in a dry tropical deciduous forest of Vindhyan highland, India. Weight loss differed among species and through months, and ranged from 15.38% in L. camara at Kotwa site in January to 30.72% in T. tomentosa at Hathinala site in August. Peak weight loss occurred in August and averaged 46.2% across species and sites. Nitrogen and phosphorus mineralization rates also varied significantly from species to species. T. tomentosa having higher nitrogen content and lower C/N ratio than other species exhibited faster weight loss. Nitrogen and phosphorus contents of litter showed significant positive correlation with weight loss. C/N ratio was negatively related to decay constant, and the weight loss was positively related to the soil surface temperature as well as soil moisture content. 相似文献
94.
Rupesh Kumar Mishra Brajesh Kumar Pandey Vijai Singh Amita John Mathew Neelam Pathak Mohammad Zeeshan 《Journal of microbiology (Seoul, Korea)》2013,51(4):405-412
Twenty one isolates of Fusarium oxysporum f. sp. psidii (Fop), causing a vascular wilt in guava (Psidium guajava L.), were collected from different agro-ecological regions of India. The pathogenicity test was performed in guava seedlings, where the Fop isolates were found to be highly pathogenic. All 21 isolates were confirmed as F. oxysporum f. sp. psidii by a newly developed, species-specific primer against the conserved regions of 28S rDNA and the intergenic spacer region. RAPD and PCR-RFLP were used for genotyping the isolates to determine their genetic relationships. Fifteen RAPD primers were tested, of which five primers produced prominent, polymorphic, and reproducible bands. RAPD yielded an average of 6.5 polymorphic bands per primer, with the amplified DNA fragments ranging from 200–2,000 bp in size. A dendrogram constructed from these data indicated a 22–74% level of homology. In RFLP analysis, two major bands (350 and 220 bp) were commonly present in all isolates of F. oxysporum. These findings provide new insight for rapid, specific, and sensitive disease diagnosis. However, genotyping could be useful in strain-level discrimination of isolates from different agro-ecological regions of India. 相似文献
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96.
The present study was designed to investigate the existence of slow and fast developing individuals and to evaluate their effect on reproductive attributes of Parthenium beetle, Zygogramma bicolorata Pallister (Coleoptera: Chrysomelidae); a biocontrol agent of Parthenium weed. Significantly different rates of development were found in a cohort of the beetle. Under constant rearing conditions, the emergence ratio of slow and fast developers was determined to be 0.47 and 0.53, respectively. Males developed faster than females, and significant differences in development were found among all immature stages and total developmental period. Slow developing females laid higher numbers of eggs with a higher percentage egg viability than fast developing females. This is the first attempt of such a study for the Parthenium beetle, and provides great insight into Parthenium beetle development for evolutionary biologists, improving our understanding of their ecological thresholds. The information could help in the selection of fast developing lines and thus in the mass multiplication of this bioagent. 相似文献
97.
Robert Bagchi Mike Crosby Brian Huntley David G. Hole Stuart H. M. Butchart Yvonne Collingham Mohit Kalra Jagadish Rajkumar Asad Rahmani Mitra Pandey Hum Gurung Le Trong Trai Nguyen Van Quang Stephen G. Willis 《Global Change Biology》2013,19(4):1236-1248
We forecasted potential impacts of climate change on the ability of a network of key sites for bird conservation (Important Bird Areas; IBAs) to provide suitable climate for 370 bird species of current conservation concern in two Asian biodiversity hotspots: the Eastern Himalaya and Lower Mekong. Comparable studies have largely not accounted for uncertainty, which may lead to inappropriate conclusions. We quantified the contribution of four sources of variation (choice of general circulation models, emission scenarios and species distribution modelling methods and variation in species distribution data) to uncertainty in forecasts and tested if our projections were robust to these uncertainties. Declines in the availability of suitable climate within the IBA network by 2100 were forecast as ‘extremely likely’ for 45% of species, whereas increases were projected for only 2%. Thus, we predict almost 24 times as many ‘losers’ as ‘winners’. However, for no species was suitable climate ‘extremely likely’ to be completely lost from the network. Considerable turnover (median = 43%, 95% CI = 35–69%) in species compositions of most IBAs were projected by 2100. Climatic conditions in 47% of IBAs were projected as ‘extremely likely’ to become suitable for fewer priority species. However, no IBA was forecast to become suitable for more species. Variation among General Circulation Models and Species Distribution Models contributed most to uncertainty among forecasts. This uncertainty precluded firm conclusions for 53% of species and IBAs because 95% confidence intervals included projections of no change. Considering this uncertainty, however, allows robust recommendations concerning the remaining species and IBAs. Overall, while the IBA network will continue to sustain bird conservation, climate change will modify which species each site will be suitable for. Thus, adaptive management of the network, including modified site conservation strategies and facilitating species' movement among sites, is critical to ensure effective future conservation. 相似文献
98.
AbstractThe glutathione S-transferase (GSTs) are polymorphic supergene family of detoxification enzymes that are involved in the metabolism of numerous potential carcinogens. Several allelic variants of polymorphic GSTs show impaired enzyme activity and are suspected to increase the susceptibility to various cancers. To find out the association of GST variants with risk of gallbladder cancer, the distribution of polymorphisms in the GST family of genes (GSTT1, GSTM1, GSTP1, and GSTM3) were studied in 106 cancer patients and 201 healthy controls. Genotypes were analysed by polymerase chain reaction (PCR) and PCR-restriction fragment length polymorphism (RFLP). The frequencies of GSTM1 null and GSTM3*BB genotypes did not differ between patients and controls. The overall frequency of GSTT1 null was lower in cases as compared with controls (p=0.003, Odds ratio (OR)?=?0.2, 95% confidence interval (CI), 0.1–0.6). After sex stratification, the GSTT1 null frequency was reduced only in female patients (p=0.008, OR?=?0.2, 95% CI?=?0.1–0.6). However, the GSTP1, ile/val genotype and the val allele were significantly higher in cases than controls (p=0.013, OR?=?1.9, 95% CI?=?1.1–3.1; p=0.027, OR?=?1.5, 95% CI?=?1.0–2.1), respectively. To study gene–gene interactions, a combined risk of gallbladder cancer due to ile/val or val/val were calculated in combination with null alleles of GSTM1 and GSTT1 or the *B allele of GSTM3, but there was no enhancement of risk. Gallstones were present in 57.5% of patients with gallbladder cancer, but there were no significant differences between allelic/genotype frequencies of the studied GST genes polymorphisms between patients with or without gallstones. To best of our knowledge, this is the first paper showing ile/val genotypes and val allele of GSTP1 to be associated with higher risk of gallbladder cancer. 相似文献
99.
A. Singh M. P. Pandey A. K. Singh R. E. Knox K. Ammar J. M. Clarke F. R. Clarke R. P. Singh C. J. Pozniak R. M. DePauw B. D. McCallum R. D. Cuthbert H. S. Randhawa T. G. Fetch Jr. 《Molecular breeding : new strategies in plant improvement》2013,31(2):405-418
Leaf rust (Puccinia triticina Eriks.), stripe rust (Puccinia striiformis f. tritici Eriks.) and stem rust (Puccinia graminis f. sp. tritici) cause major production losses in durum wheat (Triticum turgidum L. var. durum). The objective of this research was to identify and map leaf, stripe and stem rust resistance loci from the French cultivar Sachem and Canadian cultivar Strongfield. A doubled haploid population from Sachem/Strongfield and parents were phenotyped for seedling reaction to leaf rust races BBG/BN and BBG/BP and adult plant response was determined in three field rust nurseries near El Batan, Obregon and Toluca, Mexico. Stripe rust response was recorded in 2009 and 2011 nurseries near Toluca and near Njoro, Kenya in 2010. Response to stem rust was recorded in field nurseries near Njoro, Kenya, in 2010 and 2011. Sachem was resistant to leaf, stripe and stem rust. A major leaf rust quantitative trait locus (QTL) was identified on chromosome 7B at Xgwm146 in Sachem. In the same region on 7B, a stripe rust QTL was identified in Strongfield. Leaf and stripe rust QTL around DArT marker wPt3451 were identified on chromosome 1B. On chromosome 2B, a significant leaf rust QTL was detected conferred by Strongfield, and at the same QTL, a Yr gene derived from Sachem conferred resistance. Significant stem rust resistance QTL were detected on chromosome 4B. Consistent interactions among loci for resistance to each rust type across nurseries were detected, especially for leaf rust QTL on 7B. Sachem and Strongfield offer useful sources of rust resistance genes for durum rust breeding. 相似文献
100.
Vinuth N Puttamallesh Sreelakshmi K Sreenivasamurthy Pradeep Kumar Singh H C Harsha Anjali Ganjiwale Shobha Broor Akhilesh Pandey Jayasuryan Narayana T S Keshava Prasad 《Clinical proteomics》2013,10(1):14