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101.
Genetic Resources and Crop Evolution - Growth habit is a plant architectural trait in grain legumes with no exception of horse gram [Macrotyloma uniflorum (Lam.) Verdc.]. Determinacy and...  相似文献   
102.
Genetic Resources and Crop Evolution - Development of high yielding cultivars with determinate growth habit in photoperiod insensitive (PIS) background is one of the major objectives of breeding...  相似文献   
103.
The extensive use of pharmaceuticals in human and veterinary medicine may enter the aquatic environment and pose a serious threat to non-target aquatic organisms like fish. In this study, Indian major carp Cirrhinus mrigala was exposed to different concentrations (1, 10 and 100 μg L?l) of most commonly used pharmaceutical drugs clofibric acid (CA) and diclofenac (DCF) to evaluate its impacts on certain enzymological parameters during short- and long-term exposures. During short-term (96 h) exposure period, plasma glutamate oxaloacetate transaminase (GOT), glutamate pyruvate transaminase (GPT) and gill Na+/K+-ATPase activity were significantly altered at all concentrations of both the CA- and DCF-treated fish. In long-term exposure (35 days), gill Na+/K+-ATPase activity was found to be significantly increased at all concentration of CA and DCF exposures throughout the study period (except at the end of 7th day in 10 and 100 µg L-1) . However, a biphasic trend was observed in plasma GOT and GPT activity when compared to the control groups. In both short- and long-term exposure, a significant (P < 0.01 and P < 0.05) changes were observed in all enzymological parameters of fish C. mrigala exposed to different concentrations of CA and DCF. The alterations of these enzymological parameters can be effectively used as potential biomarkers in monitoring of pharmaceutical toxicity in aquatic environment and organisms.  相似文献   
104.
Ammonia is present in the aquatic environment due to agricultural runoff, sewage effluents and decomposition of biological waste. High level of ammonium in the aquatic environment or in aquaculture farms is a serious problem for aquatic organisms. In the present investigation, the sublethal effects of total ammonia nitrogen (TAN) at 9.98 mg L?1 on plasma electrolytes (Na+, K+ and Cl?) level of Indian major carp Catla catla fingerlings was studied for a period of 35 days under semistatic conditions. Exposure of fish to sublethal concentration of TAN at 9.98 mg L?1 caused changes in the levels of plasma electrolytes (Na+, K+ and Cl?) compared with control fish. No mortality was observed in any group during the treatment period. The present study reveals that the levels of plasma sodium and potassium (except on 7th day) electrolytes were significantly (< 0.05) decreased throughout the study period. However, the decrease in plasma chloride level was found to be not significant when compared with control group. The present study concludes that the measurements of plasma electrolytes levels can be used as potential biomarkers for monitoring nitrogenous chemicals in aquatic environment.  相似文献   
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106.
Maize is categorized as a salt-sensitive crop and identification of fairly salt-tolerant lines is of paramount importance for increasing its production on saline soils. Experiments were conducted in randomized block design with three replications to identify maize accessions showing response to saline water irrigation, traits imparting tolerance, and their effect on yield attributes of maize. Significant variation was present among genotypes for specific leaf area (SLA), potassium (K) content, cob characteristics, yield, biomass, and harvest index. High amount of heritability with large genetic advance indicated the presence of additive gene action for traits like leaf water potential and leaf dry weight. Association analysis revealed high correlation between key traits and direct as well as positive effect of these traits on yield. Principal component analysis resolved three principal components, and high leaf area and water potential were conferring salt tolerance and thus higher yield.  相似文献   
107.
In the recent past, biochar and crop residues have attracted lots of attention as a viable strategy for maintaining soil health. This paper evaluates the comparative effect of two different doses (equivalent to 2 and 5 t C ha?1) of each of pine needle and Lantana biochar (PBC and LBC), wheat residue and lentil residue (WR and LR) on soil biological properties, nutrient availability and yield of rice and wheat in pot culture. Energy-dispersive X-ray spectroscopy (EDS) revealed higher C content of biochar than crop residues. Evaluation of biochemical quality reflected high recalcitrance indices of C and N for both PBC and LBC. Application of LBC and PBC increased the wheat grain yield significantly by 6.2%–24.2% over control. Both PBC and LBC significantly increased N and P uptakes in grain over the control and crop residues. Both biochars recorded a significant decrease of 33.9 and 71,7% in β-glucosidase activity in comparison to control at termination of study. PBC and LBC also resulted in more soil available N, P and K in soil at different intervals. The geometric mean of enzyme activities (GMea) reflected improved soil quality by PBC and LR and reduction by LBC application.  相似文献   
108.
Whitebacked planthopper (WBPH) along with brown planthopper (BPH) has emerged as a major pest of rice in several Asian countries. Development and cultivation of varieties resistant to both planthoppers is an ecologically acceptable strategy to manage these pests. Sinna Sivappu, a Sri Lankan landrace, was reported to be resistant to both planthoppers. While inheritance of BPH resistance has been reported, the genetics of WBPH resistance in this variety is not known. Using a mapping population of 255 F2:3 families from Taichung Native (TN)1/Sinna Sivappu cross and 128 polymorphic simple sequence repeat (SSR) markers, genes or quantitative trait loci (QTLs) for WBPH resistance quantified in ten phenotypic tests were identified, adopting classical Mendelian segregation, correlation and QTL analyses. The inheritance pattern suggested that a single recessive gene controlled regulation of seedling damage score. Antixenosis or nymphal preference was influenced by two complementary recessive genes, whereas tolerance in terms of days to wilt was under the influence of a single dominant gene. Several of these phenotypic tests recorded high degree of positive or negative correlation between them, suggesting dependence or redundancy of the tests. QTL analysis revealed 13 loci associated with nine traits. Five major-effect QTLs were detected for damage score (chromosome 6), nymphal survival (chromosome 12), and days to wilt (three QTLs on chromosome 4). We suggest involvement of four WBPH resistance genes in Sinna Sivappu, designated as wbph9(t), wbph10(t), wbph11(t), and Wbph12(t). One of the recessive genes could be allelic to any of the recessive genes reported in cluster C on chromosome 6 which might confer resistance to both BPH and WBPH.  相似文献   
109.
Mycoplasma ovis is a hemoplasma parasite of sheep, goats, and reindeer; however, natural hemoplasma infection in white-tailed deer has not previously been reported. Subsequent to finding many coccoid, bacillary, and ring-shaped organisms, consistent with hemotropic mycoplasmas, on RBCs from a 72-day-old female white-tailed fawn, we sought to (1) identify the putative hemoplasma observed in blood from the fawn, (2) evaluate others in the herd for hemoplasma infection, and (3) identify clinicopathologic characteristics of hemoplasma-infected white-tailed deer. EDTA-anticoagulated whole blood was collected from the fawn and 8 apparently healthy does in the same herd. CBCs were performed on 7 nonclotted samples from the fawn and 6 does. DNA was extracted from all samples, followed by PCR amplification of bacterial (16S rDNA) and protozoal (18S rDNA) genes. The nearly complete 16S rDNA product from the fawn's sample was directly sequenced and compared with known sequences in the GenBank database. Samples from the fawn and 7 of 8 does were PCR-positive using hemoplasma-specific and M ovis-specific protocols. The fawn was PCR-negative for Anaplasma spp., Babesia spp., and Theileria spp. The 16S rDNA sequence from the fawn (GenBank accession number, FJ824847) was most closely related to M ovis (AF338268), having 98.5% sequence identity. The fawn had a mild nonregenerative anemia, a neutrophilic left-shift with toxic change, aspiration bronchopneumonia, and gastrointestinal disease. Hematologic values, including blood film evaluation, in infected does were unremarkable. The M ovis-like organism may have acted as either an opportunistic or primary pathogen in the fawn. The high occurrence of subclinical infections in the does suggests that white-tailed deer may act as wildlife reservoirs for M ovis.  相似文献   
110.
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