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91.
G. V. Subbarao C. Johansen J. V. D. K. Kumar Rao M. K. Jana 《Biology and Fertility of Soils》1990,9(1):49-53
Summary There were significant differences among pigeonpea [Cajanus cajan (L.) Millsp] Rhizobium sp. strains (IC 3506, IC 3484, IC 3195, and IC 3087) in their ability to nodulate and fix N2 under saline conditions. Pigeonpea plants inoculated with IC 3087 and IC 3506 were less affected in growth by salinity levels of 6 and 8 dS m-1 than plants inoculated with the other strains. For IC 3506, IC 3484, and IC 3195, there was a decrease in the number of nodules with increasing salinity, while the average nodule dry weight and the specific nitrogenase activity remained unaffected. However, in IC 3087, the number of nodules increased slightly with increasing salinity. Leaf-P concentrations increased with salinity in the inoculated plants irrespective of the Rhizobium sp. strain, and leaf-N concentrations decreased with increasing salinity in IC 3484 and IC 3195 only. Shoot-Na and-Cl levels were further increased in these salt-sensitive strains only at 8 dS m-1. Therefore there may be scope for selecting pigeonpea Rhizobium sp. symbioses better adapted to saline conditions. The Rhizobium sp. strains best able to form effective symbioses at high salinity levels are not necessarily derived from saline soils.Submitted as JA No. 919 by the International Crops Research Institute for the Semi-Arid Tropics (ICRISAT) 相似文献
92.
Heat-induced aggregation of whey proteins in solutions made from two commercial whey protein concentrates (WPCs), one derived from mineral acid whey (acid WPC) and the other from cheese whey (cheese WPC), was studied using polyacrylamide gel electrophoresis (PAGE), size exclusion chromatography (SEC), and transmission electron microscopy (TEM). Heat treatment (75 degrees C) of acid WPC solutions (12.0%, w/w, pH 6.9) resulted in formation of relatively small "soluble" aggregates that were predominantly disulfide-linked. By contrast, heat treatment of the cheese WPC solutions (under the same conditions) caused formation of relatively large aggregates, containing high proportions of aggregates linked by noncovalent associations. The rate of aggregation of both beta-lactoglobulin and alpha-lactalbumin at 75 degrees C, measured as the loss of native proteins by PAGE, was higher in the cheese WPC solution than in the acid WPC solution. Cross dialysis of the two WPC solutions resulted in alteration of the mineral composition of each WPC solution and reversing their heat-induced aggregation behavior. The results demonstrated that the mineral composition is very important in controlling the aggregation behavior of WPC products. 相似文献
93.
Effect of Temperature on Bio-Kinetic Coefficients in UASB Treatment of Municipal Wastewater 总被引:1,自引:0,他引:1
Upflow anaerobic sludge blanket (UASB)reactors were used to treat municipal wastewater attemperatures of 6, 11, 15, 20 and 32 °C and athydraulic retention times (HRTs) ranging from 48 to 3 h overan operational period of approximately 860 days. The Monodmodel was used to evaluate substrate utilization. TheArrhenius model was used to calculate the activationenergies from which temperature coefficients weredetermined. It was found that the maximum specific substrateutilization rate constant (k) decreased from 0.387 d-1(at 32 °C) to 0.041 d-1 (at 6 °C). Thedecay rate constant (kd), yield coefficient (Yg),half velocity constant (Ks) and maximum specific growthrate (μm ) were also impacted by temperature in theUASB treatment of municipal wastewater. 相似文献
94.
Transplanting of rice seedling in puddled soil is one of the most widely used cultivation practices. The present research is aimed at determining what specific implements are needed to obtain optimal puddle bed for transplantating. Puddling experiments were carried out by the use of pair of bullocks with traditional country plough (T1), pair of bullocks with lug wheel puddler (T2), power tiller with rotary puddler (T3), tractor with cage wheel and 9-tine cultivator (T4) and tractor with cage wheel and rotavator (T5). One summer ploughing was done at friable moisture condition (18.6% db) and then tilled soil was flooded to saturation (24 h) for preparation of puddled bed. Weeding efficiency, puddling depth, percentage increase in bulk density, puddling index, percolation rate and grain yield of paddy were studied for the above treatments. Puddling performance by different implements in comparison to the traditional animal drawn country plough (T1) shows that there is a definite reduction in time requirement for field preparation. Increase in weeding efficiency, bulk density, grain yield and puddling index were also observed. The highest values of weeding efficiency and puddling index were found 98.6% and 79.3, respectively, for rotavator (T5). The total time requirement for preparation of puddle field for treatment T4 (tractor with cultivator) was found to be the lowest (9.4 h ha−1) with 67% weeding efficiency and 62.7 puddling index as compared to all other alternatives tested. Energy requirement for preparation of puddle field was found highest (2390 MJ ha−1) for rotavator (T5) followed by T3, T4, T1, and T2 treatments. 相似文献
95.
Vinod Kumar Yadav Sandeep Kumar Ravindra K. Panwar 《Genetic Resources and Crop Evolution》2007,54(6):1285-1289
The present investigation was carried out on fifteen germplasm lines of Pisum sativum L. were used for characterization using Randomly Amplified Polymorphic DNA (RAPD) markers. While 12 random primers were taken,
out of them 11 primers gave amplification. These primers gave a total of 133 bands out of which 106 were polymorphic. Genetic
similarities of the RAPD profiles were estimated by using Jaccard’s coefficient with NTSYSpc 2.0 software. The similarity
index values ranged from 0.263 to 0.793 indicating the presence of enormous genetic diversity at molecular level. A dendrogram
generated by cluster analysis divided fifteen fieldpea genotypes into two Groups A and B. Major Group A have five genotypes
and major Group B have nine genotypes. 相似文献
96.
The development of appropriate technologies for the judicious use of India's 8.11 million ha of salt-affected lands would give increased food, fodder and fuelwood production. A sizeable portion of the salt-affected lands of the Indo-Gangetic plain have been reclaimed through chemical amendments and are being commercially used for arable farming. However, large areas of salt-affected common lands, village and government lands and waste lands near cities, along railway tracks and roads do not have any productive use. Owing to their sparse vegetative cover such lands are vulnerable to further degradation and can be a source of runoff causing floods, especially where cows congregate. Research at the Central Soil Salinity Research Institute, Karnal has generated agroforestry techniques which could enable the economic exploitation of such marginal lands. This paper deals with various aspects of these techniques, which have been applied to over 50 000 ha by 1994. Based on eight to ten years of growth and biomass figures, the most salt-tolerant woody species identified were: Prosopis juliflora, Acacia nilotica, Casuarina equisetifolia, Tamarix articulata, Leptochloa fusca (a palatable forage grass which was found to be a promising primary colonizer of salt lands). Agronomic practices for the successful establishment of trees such as planting methods, amendment use, irrigation, spacing and lopping schedules are discussed. A Prosopis juliflora-leptochloa fusca silvipastoral model was found to be excellent for fuelwood and forage production and for the amelioration of high pH soils. This system, when followed for little more than four years, reclaims alkali soils to such an extent that normal agriculture crops such as Trifolium alexandrinum and T. resupinatum can be grown successfully. A ridge-trench system of tree planting was found to be helpful in alkali soils, the in situ rainwater conservation it led to assisting biomass production. Eucalyptus tereticornis, Populus deltoides and Tectona grandis based agroforestry were promising for reclaimed salt-affected lands. The short- and long-term effects of various tree plantations on the physicochemical properties of the soil and on soil-water relations are also discussed. Agroforestry options for the development of salt-affected lands found in various agroclimatic zones of India are explored. 相似文献
97.
Moharana P. C. Jena R. K. Pradhan U. K. Nogiya M. Tailor B. L. Singh R. S. Singh S. K. 《Precision Agriculture》2020,21(2):426-448
Precision Agriculture - Delineation of management zones (MZs) are needed to manage fields in order to maximize economic return, minimize environmental impact, and improve soil and crop management.... 相似文献
98.
Kumar Sandopu Sravan Arya Monisha Nagbhushan Priyanka Giridhar Parvatam Shetty Nandini P. Yannam Sudheer Kumar Mahadevappa Paramesha 《Plant foods for human nutrition (Dordrecht, Netherlands)》2020,75(2):283-291
Plant Foods for Human Nutrition - The aim of this study was to assess the efficiency of different drying methods (room, sun, oven, microwave, cross-flow, infra-red, dehumidifier, and freeze-drying)... 相似文献
99.
Shekhar Shashank Mailapalli Damodhara Rao Raghuwanshi Narendra Singh Das Bhabani Sankar 《Paddy and Water Environment》2020,18(1):73-85
Paddy and Water Environment - Alternate wetting and drying (AWD) irrigation practice in paddy cultivation requires a safe soil moisture stress level in the root zone for which irrigation water... 相似文献
100.
Kwasi Bannor Richard Amarnath Krishna Kumar Gupta Oppong-Kyeremeh Helena Abawiera Wongnaa Camillus 《水稻科学》2020,27(1):56-66
The factors affecting the adoption of modern varieties(MVs) of rice and impact on poverty in Odisha, India were discussed. A total of 363 households from Cuttack and Sambalpur districts of Odisha via multistage sampling technique participated in the survey. The Cragg's Double hurdle model was used to model the determinants of adoption and intensity of adoption of MVs of rice, and the propensity score matching was used to analyze the impact of adoption on poverty. The results showed that age, education, risk aversion, land size, yield, perception of MVs as high yielding, resistant to diseases and availability of MVs positively influenced the decision to adopt. However, variables such as household size, experience of a farmer, off-farm job participation, amount of credit received, cost of seeds, insecticides and fertilizers negatively influenced the adoption of MVs. Intensity of adoption of MVs was negatively influenced by experience of a farmer, cost of fertilizer and marketability of MVs, and positively affected by household size, risk aversion, land size, cost of insecticides, perception of MVs as high yielding and availability of MV seeds. Poverty incidence, gap and severity were high among non-adopters to adopters of MVs. After matching adopters and non-adopters of MV groups using four different algorithms of nearest neighbour matching, stratification matching, radius matching and kernel matching, the impact of MV adoption resulted in higher per capita monthly household expenditure by about US$ 52.82 to US$ 63.17. 相似文献