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1.
In vegetable brassicas, cytoplasmic male sterility (CMS) system is the most preferred mechanism for hybrid seed production and Ogura cybrid cytoplasm is the only source used widely. Effects of the alien cybrid cytoplasm on important quality traits need to be understood for their effective use in breeding programme. In analysing 38 Ogura cybrid cytoplasm‐based cauliflower CMS lines, it was revealed that introgression of Ogura cytoplasm resulted in significant alteration in important quality traits. Cupric reducing antioxidant activity and ferric reducing ability of plasma values were increased up to 5–10 times in different genotypes. Among 38 analysed CMS lines, concentration of plant pigments such as anthocyanin, total chlorophylls and ascorbic acid was reduced in 21, 17 and 32 genotypes, respectively. However, the concentration of total carotenoids and β‐carotene was elevated in most of the CMS lines and total carotenoid was increased up to 20 times in the CMS line, Ogu13‐85‐2A. The results indicate the role of nuclear–cytoplasmic interaction and mitochondrial genome in determining concentration of different quality traits.  相似文献   
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Phytoparasitica - Diaeretiella rapae (McIntosh) (Hymenoptera: Braconidae) is one of the most promising, effective and a common endoparasitoid of different aphid species including cabbage aphid,...  相似文献   
3.
Real-time adaptive irrigation scheduling under a limited water supply   总被引:5,自引:0,他引:5  
The problem of real-time irrigation scheduling under limited water supply is considered. The goal is to develop an irrigation operation policy which maximizes crop yields and is responsive to current season changes in weather and other variables. Because irrigation decisions are sequential and dependent on crop and soil water status, and also because crop yields can only be known at the end of the season, the decisions are arrived at by a two-stage process. In the first or the design stage, irrigations are planned for the entire season at weekly intervals using historical data and an optimal irrigation scheduling model. In the second stage, the decisions for the subsequent weeks are revised each week after updating the status of the system with real time data up to that week and solving the irrigation optimization model once again for the new conditions. Thus, each week an irrigation decision is made, the entire planning horizon is kept in view. The procedure is illustrated by application to a case study.  相似文献   
4.
Increasing fiscal constraints on the government, a lackadaisical performance by public sector animal health and breeding services and pressure from donor partners have prompted the governments of various developing countries to rethink the role of the public sector in the provision of veterinary services. Various countries have started to implement, or have already implemented, privatization of some veterinary services. The results are mixed. It is established that private provision alone is not optimal, and a blend of private and public sector veterinary services is required to utilize the virtues of both.The privatization process has also begun in India. Certain state governments in India are pursuing a cost recovery approach and are encouraging private practitioners to cope with the financial constraints and to deliver broad and effective animal health and breeding services. This paper considers the global aspects of the privatization of veterinary services as well as the scenario in India, so as to gain an insight into the very complex and debatable issue of privatization of veterinary services.  相似文献   
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Monolayer and multilayer structures of C(60), a high temperature van der Waals solid, have been studied with scanning tunneling microscopy. Structures grown on GaAs(110) at 300 kelvin and at elevated temperatures show significantly different morphologies because of balances between thermodynamics and kinetics. Condensation onto stepped surfaces demonstrates preferred bonding and nucleation at step edges. Detailed studies of potassium incorporation in crystalline C(60) show highly ordered structures in the K(3)C(60) metallic state but disordered non-metallic structures for high potassium concentrations.  相似文献   
7.
The tetracycline resistance gene, tet(B), has been described previously in Gram negative bacteria. In this study tet(B) was detected in plasmid extracts from 17/111 (15%) Streptococcus suis isolates from diseased pigs, representing the first report of this resistance gene in Gram positive bacteria.  相似文献   
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Soil microbiological properties during decomposition of leaf litter of poplar (Populus deltoides) and eucalyptus (Eucalyptus tereticornis) were studied under laboratory conditions. Microbial biomass C and ninhydrin-N were measured at different intervals up to 90 days following incorporation of poplar and eucalyptus leaves separately @ 20 and 100t ha-1. In general, the net increase in total biomass C or ninhydrin N following amendment was larger in the soils which received poplar leaves than in the soils that received eucalyptus leaves. The amounts of biomass C, at day 90, in the soils which received eucalyptus leaves @ 20 and 100 t ha-1 was about half and one-third, respectively, that of the soils that received poplar leaves at the same rates. Similarly, the field soils naturally receiving eucalyptus leaf litter contained about half the amounts of biomass C or ninhydrin N of the soils that received poplar leaf litter. In contrast, the amounts of organic C and total N were more in soils which received eucalyptus leaves both in the laboratory experiment and under field conditions than in the soils that received poplar leaves, indicating that the decomposition of eucalyptus leaves in soils was slower than that of poplar leaves. The ratio of biomass C/soil organic C in soils receiving eucalyptus leaves was about 2–4 times lower than those in soils with no admendment or soils receiving poplar leaves. These results, therefore, suggest that the allelochemicals released into soil during decomposition of eucalyptus leaves had a toxic effect on soil microorganisms and may thus affect the nutrient cycling and hence soil fertility.  相似文献   
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