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401.
Summary The effect of green manuring and soil amendments in various combinations on common scab of potato have been investigated.
Soybean green manuring in combination with partially decomposed wheat straw was most effective with a decrease of 56.9% and
54.8% respectively in scab index and scab incidence. There was also a 14.2% increase in potato yield. Soil microbial population
was also studied and a considerable increase in bacterial population was observed with soybean green manuring. Maximum population
was recorded at planting and at harvest, microbial population was drastically decreased. 相似文献
402.
Dietary ascorbic acid requirement for growth of striped catfish,Pangasianodon hypophthalmus (Sauvage, 1878) juveniles 下载免费PDF全文
N. Daniel A.P. Muralidhar P.P. Srivastava K.K. Jain K. Pani Prasad J. Manish T. Sivaramakrishnan 《Aquaculture Nutrition》2018,24(1):616-624
A sixty‐day feeding trial was conducted to determine the ascorbic acid (AA) requirement for growth of striped catfish, Pangasianodon hypophthalmus juveniles. Seven iso‐nitrogenous and iso‐energetic (370 g protein per kg and 19.6 MJ/kg) purified diets were prepared with different levels of ascorbic acid such as control (0), T1 (17.5), T2 (35), T3 (70), T4 (175), T5 (350) and T6 (700) mg ascorbic acid (L‐ascorbyl‐2‐polyphosphate) equivalent per kg diet. Fish with a mean body weight of 3.2–3.4 g were stocked (fifteen fish per tank) in triplicates following a completely randomized design. Each group was fed to satiation twice a day for 60 days. Significant differences were observed in growth, survival, body composition and metabolic enzymes activities with different dietary ascorbic acid levels. Maximum weight gain, specific growth rate (SGR) and protein efficiency ratio (PER) were found in fishes fed with 35 mg AA per kg diet, supported by best feed conversion. Fish fed a diet containing vitamin C had the highest activities of aspartate aminotransferase (AST), alanine aminotransferase (ALT) and alkaline phosphatase (ALP) compared to those fed with vitamin C‐depleted diets. In this study, based on using broken‐line regression analysis, the dietary vitamin C requirement for growth of P. hypophthalmus juveniles was estimated to be in the range of 46–76 mg AA per kg, depending on the criterion used, growth and liver storage. Our results will be helpful for the formulation of cost‐effective ascorbic acid incorporated diets for striped catfish, P. hypophthalmus. 相似文献
403.
The effect of the micronutrient manganese (Mn) on the physiological performance of green gram [Vigna radiata (L.) R. Wilczek] under saline condition was studied in the present work. Green gram was grown under controlled conditions and treated with different concentrations of sodium chloride (NaCl): 100, 200, and 300 mM. The plant samples were analyzed from 25 to 65 days of plant growth at every 10-day interval. Significant difference was observed in leaf area index, membrane stability index, nitrate reductase enzyme activity, total chlorophyll, and carotenoid content in treated plants. A drastic reduction was recorded at 200 and 300 mM NaCl treated plants in the parameters. The concentration 100 mM resulted in a slight increase of the parameters. Foliar application of Mn as manganese chloride (MnCl2) was found to improve the physiological parameters in green gram at 200 and 300 mM salinity level and was useful in alleviating the detrimental effects of NaCl. 相似文献
404.
K. S. Rawat S. C. Bhatt S. P. Pachauri P. C. Srivastava 《Communications in Soil Science and Plant Analysis》2017,48(8):857-864
Kinetics and adsorption-desorption behavior of a potent nitrification inhibitor, 2-amino 4-chloro 6-methyl pyrimidine (AM), was examined in Mollisol samples of different depths. Adsorption of AM was better accounted by pseudo-second order kinetics. Adsorption and desorption data of AM onto soil samples of different depths conformed to single surface Freundlich isotherm model. The values of ln K varied from ?0.1515 (0–15 cm) to 1.5171 (45–60 cm) and of 1/n from 0.9961 (45–60 cm) to 1.3237 (30–45 cm). Computed values of desorption capacity (ln K’) varied from 3.4734 (0–15 cm) to 4.0674 (45–60 cm) while that of 1/n´ from 0.0017 (45–60 cm) to 0.0367 (0–15 cm). Intensity of desorption (1/n´) had significant positive correlation with soil electrical conductance and clay content. The values of desorption index (n´/n) varied from 14.60 (0–15 cm) to 472.33 (30–45 cm) indicating high degree of irreversibility of adsorbed AM and hence poor leaching from these soils. 相似文献
405.
Sujata Misra Awadhesh Kumar Srivastava Sushma Verma Sudhakar Pandey Surendra Singh Bargali Tikam Singh Rana K. Narayanan Nair 《Genetic Resources and Crop Evolution》2017,64(5):995-1010
Genetic variations and relationships among cultivated and wild genotypes of five taxa of Indian Luffa were examined using inter simple sequence repeats (ISSR), directed amplification of minisatellite DNA (DAMD) markers and morphological characterization. Morphometric evaluation of 21 discrete characters in 51 representative accessions segregated the five taxa of Luffa in three main clusters: the two wild species (L. echinata, L. graveolens) in the first, and the cultivated L. aegyptiaca (smooth gourd) and L. acutangula (ridged gourd)/L. hermaphrodita (Hermaphrodite luffa) in the second and third clusters, respectively. Cumulative data analysis of 15 ISSR and seven DAMD markers revealed high percentage polymorphism (97.67 %), moderate genetic distance (0.06–0.72, avg. 0.51), and low heterozygosity and Shannon index values (H = 0.15; I = 0.22) across all the 76 genotypes assayed. A UPGMA dendrogram, based on the combined marker data, resolved the five taxa in two main clusters with high bootstrap support. The morphological and molecular trees showed incongruence in the number of main clusters resolved and in the disposition of the wild and cultivated taxa in different sub-clusters. The cluster analyses and PCoA plots revealed a nested grouping of the hermaphrodite luffa within the ridge gourd group. The Bayesian STRUCTURE analysis identified three genetic clusters for the five assumed taxa. Outcrossing test revealed a mixed mating system in Indian Luffa. This is the first ever report on the mating system in Luffa using molecular markers. The study also demonstrates the utility of using more than one DNA marker in the assessment of molecular diversity in a widely cultivated crop genus like Luffa with a narrow genetic base. 相似文献
406.
Shreya Srivastava Basdeo Kushwaha Jyoti Prakash Manmohan Pandey Suyash Agarwal Ravindra Kumar N. S. Nagpure Mahender Singh Paramananda Das Chaitanya Joshi Joy Krushna Jena 《Fisheries Science》2017,83(2):265-272
Magur Clarias batrachus is an indigenous catfish, commonly found in India, Nepal, Bhutan and Bangladesh. Presently, the populations of magur have declined rapidly in their natural habitat mainly due to overexploitation and habitat degradation. Understanding the population genetic structure of the species has significance in improvement of stocks and in conservation of the species. In the present study, simple sequence repeat (SSR) markers were used to differentiate the populations of magur, collected from three geographic locations. For this, a total of 31,814 SSRs were mined from the de novo assembled pooled of whole genome sequence data of C. batrachus. A bioinformatics pipeline with stringent criteria was applied to analyze the data which resulted in selection of 30,142 microsatellite loci falling in the intergenic region. Out of the 25 loci selected for primer development, 16 loci were successfully amplified and 9 loci were found to be polymorphic in this species. The average observed as well as expected heterozygosity in the loci across different stocks varied from 0.652 to 0.688 and 0.864 to 0.873, respectively. These three populations were further segregated into two clusters based on the NJ genetic distance. The Lucknow population formed one cluster, while the Bhubaneswar and Kolkata populations constituted another cluster. A comparable finding was also deduced from the STRUCTURE analyses. The results revealed significant variation among the populations of C. batrachus under study. 相似文献
407.
Garima Anand Prem Prakash Srivastava Tincy Varghese Narottam P. Sahu Vungarala Harikriskna Martin Xavier Iffat Jahan Dharmaraj Patro 《Aquaculture Research》2020,51(6):2483-2494
A feeding trial was conducted to evaluate the effect of inclusion of Sesbania leaf meal in the diet of Cyprinus carpio as a replacer of de‐oiled rice bran (DORB). Bacillus subtilis was used to ferment the Sesbania leaf meal (SLM) to produce FSLM (fermented sesbania leaf meal). Fishes were fed with five isonitrogenous (30% CP) and isocaloric diets for 60 days and treatments were viz., C (30% DORB, 0% SLM), R15 (15% DORB, 15% SLM), R30 (0% DORB, 30% SLM), F15 (15% DORB, 15%FSLM) and F30 (0% DORB, 30% FSLM) by replacing DORB with SLM. A similar growth performance with control was observed in 15% FSLM group while there was a growth reduction in all the raw leaf meal fed groups. Similarly, the expression of insulin‐like growth factor‐1 (IGF‐1) was significantly (p < .05) higher in control and 15% FSLM fed groups. Growth and metabolic enzymes such as protease, amylase, ALT and AST activities were significantly higher in the fermented leaf meal fed groups compared to their non‐fermented counterparts. Antioxidant enzymes, serum transaminase enzymes (SGOT, SGPT) and total bilirubin (TBR) were found to be increased by enhanced level of RSLM, however, reduced by inclusion of FSLM. However, 30% inclusion level of FSLM even after fermentation showed detrimental effect on growth and metabolic response at cellular and molecular level. Thus, the results concluded that fermented Sesbania leaf meal (FSLM) using B. subtilis could replace 50% DORB (15% FSLM group) in the diet of C. carpio without affecting the growth and other physiological responses. 相似文献
408.
Kumar Antul Sharma Achla Sharma Rajni Choudhary Anuj Srivastava Puja Kaur Harmanjot Padhy Asish Kumar 《Genetic Resources and Crop Evolution》2022,69(1):411-430
Genetic Resources and Crop Evolution - Gradual deterioration in water resources and unpredictable distribution pattern of annual precipitation amount are major threats having drastic effects on... 相似文献