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Tropical Animal Health and Production - Female fertility in domestic animals in India has exhaustively suffered owing to indiscriminate breeding with single objective of increasing milk production....  相似文献   
23.
Bacillus coagulans, a phosphatase- and phytase-producing bacterium was isolated and tested under greenhouse conditions and in the field in a loamy sand soil. Bacterial population build-up and efficiency was compared under sterilized and non-sterilized soil conditions. Exploitation of plant unavailable (poorly soluble) P was higher in sterilized soil, mainly due to an increased bacteria population. A gradual increase in microbial build-up of up to 21 times the inoculated population was observed over a 4-week period under the sterilized soil condition. Clusterbean influenced acid phosphatase and phytase activity. The depletion of organic P was much higher than the depletion of mineral and phytin P. The microbial contribution to the hydrolysis of the different P fractions was significantly higher than the plant contribution. The maximum effect of inoculation on different enzyme activities (acid phosphatase, alkaline phosphatase, phytase and dehydrogenase) was observed in pants between 5 and 8 weeks of age. A significant improvement in plant biomass (25%), root length (28%), plant P concentration (22%), seed (19%) and straw yield (28%) resulted from inoculation. The results suggested that B. coagulans produces phosphatases and phytase, which mobilized P from unavailable native P sources and enhanced the production of clusterbean.  相似文献   
24.
Fresh rhizomes of 18 diploid and tetraploid genotypes of Indian ginger, including commercial cultivars and experimental genotypes, were assayed for gingerol content and antioxidant activity. The tetraploid ginger type was derived from the respective diploid ginger by shoot tip culture. [6]-Gingerol was identified as the major pungent phenolic compound in all samples (mean 1354.78 ± 470 μg/g), while [8]- (mean 180.94 ± 45 μg/g) and [10]-gingerol (mean 234 ± 79 μg/g) occurred in lower concentrations. The total gingerol content of the tetraploid type was much higher than that of the respective diploid type and especially the [10]-gingerol. Both diploid and tetraploid types of the cv. Meghalaya Local contained the highest level of gingerol. At both ploidy levels, the genotypes showed significant differences in phenols and antioxidant activities. Correlation of total phenolics with different antioxidant assay at both diploid and tetraploid level was linear and strong to moderate. For genotypes at both ploidy levels, antioxidant activity (BCO) was determined especially by [6]-gingerol while [8]- and [10]-gingerol did not affect BCO. These results demonstrated that in the tetraploid types of ginger, the gingerol content and antioxidant activity were higher than in the diploid ones.  相似文献   
25.
Eighteen different cabbage cultivars were assayed for variability between the cultivars for the antioxidant phytonutrients. The Vitamin C content ranged from 5.66 to 23.50 mg/100 g fresh weight. The maximum Vitamin C content was recorded in cultivar Sprint Ball (23.50 mg/100 g), followed by cv. Gungaless (12.86 mg/100 g). The β-carotene content in cabbage ranged from 0.009 to 0.124 mg/100 g fresh weight. The maximum β-carotene content was recorded in cv. Quisto (0.124 mg/100 g), followed by Green Challenger (0.115 mg/100 g) and Rare Ball (0.114 mg/100 g). The minimum values for β-carotene was noted in cv. Pusa Mukta (0.009 mg/100 g). Lutein content was also recorded in the cabbage cultivars, which ranged from 0.021 to 0.258 mg/100 g fresh weight. Maximum lutein content was recorded in Quisto (0.258 mg/100 g) and minimum in Pusa Mukta (0.021 mg/100 g). Vitamin E (dl-α-tocopherol) was estimated only in 14 cabbage cultivars, which ranged from 0.030 to 0.509 mg/100 g fresh weight. Maximum α-tocopherol content was recorded in Rare Ball (0.509 mg/100 g) and minimum in Green Cornell (0.030 mg/100 g). Total phenol content was also estimated only in 14 cultivars and the values ranged from 12.58 to 34.41 mg/100 g fresh weight. Amongst the three different cultivated forms of cabbage, red cabbage had higher Vitamin C (24.38 mg/100 g), dl-α-tocopherol (0.261 mg/100 g) and phenolic content (101.30 mg/100 g) as compared to the white cabbage and savoy cabbage.  相似文献   
26.
Helicoverpa armigera (Hübner) (Noctuidae: Lepidopetra) is a polyphagous pest of major crops grown in India. To prevent the damage caused by H. armigera farmers rely heavily on insecticides of diverse groups on a regular basis which is not a benign practice, environmentally and economically. To provide more efficient and accurate information on timely application of insecticides, this research was aimed to develop a forecast model to predict population dynamics of pod borer using Autoregressive Integrated Moving Average (ARIMA) and Artificial Neural Networks (ANN). The data used in this study were collected from the randomly installed sex pheromone traps at International Crops Research Institute for the Semi-arid Tropics (ICRISAT), Patancheru, Hyderabad. Several ARIMA (p, d, q) (P, D, Q) and ANN models were developed using the historical trap catch data. ARIMA model (1,0,1), (1,0,2) with minimal BIC, RMSE, MAPE, MAE, and MASE values and higher R2 value (0.53) was selected as the best ARIMA fit model, and neural network (7-30-1) was found to be the best fit to predict the catches of male moths of pod borer from September 2021 to August 2023. A comparative analysis performed between the ARIMA and ANN, shows that the ANN based on feed forward neural networks is best suited for effective pest prediction. With the developed ARIMA model, it would be easier to predict H. armigera adult population dynamics round the year and timely intervention of control measures can be followed by appropriate decision-making schedule for insecticide application.  相似文献   
27.
Since the 1980s, the widespread use of N fertilizer has not only resulted in a strong increase in agricultural productivity but also caused a number of environmental problems, induced by excess reactive N emissions. A range of approaches to improve N management for increased agricultural production together with reduced environmental impacts has been proposed. The 4R principles(right product, right amount, right time and right place) for N fertilizer application have been essential for improving...  相似文献   
28.
The ion exchange equilibria and mechanism of Zn exchange with Na montmorillonite has been studied with the help of adsorption isotherms and thermodynamic parameters. The exchange isotherms, K and △G° values indicated a spontaneity of reaction and a higher preference of Zn for the montmorillonite surface. A stronger binding of Zn and changes in the hydration rates of Zn and Na with increase in order were suggested by enthalpy an entropy effects respectively. The surface phase activity coefficients and the excess thermodynamic functions were indicative of a nonideal heterogeneous exchange in which the mixture of ions on the montmorillonite surface was more stable and more tightly bound with significant differences in the hydration rates of the ions in the mixture with respect to the homo-ionic forms.  相似文献   
29.
Agroforestry Systems - This article presents a methodology for the valuation of agroforestry with respect to fuelwood supply for cooking and its opportunity cost. The share of fuelwood consumption...  相似文献   
30.
Human-modified tropical landscapes under semi-natural or agro-ecosystems often harbor biodiversity of significant conservation value. In the Western Ghats of India, these ecosystems also provide connectivity between protected areas and other remnant forests. We investigated the conservation value of these landscapes and agro-ecosystems using results from 35 studies covering 14 taxonomic groups. Large, conspicuous taxonomic groups and tree-covered land-use types have received much focus in this area of research in the Western Ghats. We computed a response ratio defined as the log ratio of species richness in human land use to species richness in forest control site from 17 studies. In a meta-analysis, we investigated variation of this ratio across studies with respect to three variables: taxonomic group, the land-use type sampled and the extent of forest cover within the study landscape. Higher forest cover within the landscape emerged as a major positive influence on biodiversity in human-modified landscapes for vertebrates and vegetation while no patterns emerged for invertebrates. Our results suggest that loss of remnant forest patches from these landscapes is likely to reduce biodiversity within agro-ecosystems and exacerbate overall biodiversity loss across the Western Ghats. Conservation of these remnant forest patches through protection and restoration of habitat and connectivity to larger forest patches needs to be prioritized. In the densely populated Western Ghats, this can only be achieved by building partnerships with local land owners and stakeholders through innovative land-use policy and incentive schemes for conservation.  相似文献   
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