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91.
Koontz HV Prince RP 《HortScience : a publication of the American Society for Horticultural Science》1986,21(1):123-124
A 50% increase in total radiation by extending the photoperiod from 16 to 24 hr doubled the weight of all cultivars of loose-leaf lettuce (Lactuca sativa L.) 'Grand Rapids Forcing', 'Waldmanns Green', 'Salad Bowl', and 'RubyConn', but not a Butterhead cultivar, 'Salina'. When total daily radiation (moles of photons) was the same, plants under continuous radiation weighed 30% to 50% more than plants under a 16 hr photoperiod. By using continuous radiation on loose-leaf lettuce, fewer lamp fixtures were required and yield was increased. 相似文献
92.
This paper presents a new tool, developed with the aim of assessing the environmental impact from industrial effluents and sewage systems in Hanumante River and to recommend the finest procedures to control water pollution so as to improve the water quality of Hanumante River using environmental system analysis. Hanumante River is heavily polluted due to inefficient management resulting in water-associated problems. The time horizon for this study is from 2000 to 2030, yearly, and the spatial boundary is considered to be Hanumante River, Bhaktapur, Nepal. The stakeholder, function, and scenario analyses are employed as three tools for study. The participation of main stakeholders aids in resolving their various conflicting interests in Hanumante River, thus creating a common understanding about the crisis under study. A complete functional analysis illustrates various functions fulfilled by the river and their associated services. Based on the interests of the stakeholders and their priorities, two alternatives resulting in four scenarios are identified and ranked against four selected criteria. A combination of improved industrial technology and efficient municipal waste management gives the best solution to the pollution problem in Hanumante River. Different alternative themes have corresponding effects on the selected criteria. The choice is in the hands of the decision makers of Bhaktapur City. The outcome of this paper will ultimately help decision and policy makers to analyze the environmental impact of river systems and find efficient and better-quality decision making for water resource management incorporating the knowledge and experiences of various stakeholders. 相似文献
93.
Abstract Wodlly apple aphid Eriosoma lanigerum (Hsm.) is widely distributed in India. It reproduces all year round on apple and crab apple. Alates are produced from July to November and lay nymphs with degenerate mouth parts. The infestation is spread by nursery plants and air currents. The pest is controlled in the nursery either by dip-treatment with fenitrothion (0.025%) or dichlorvos (0.088%) or by soil application of phorate granules (2.5–3.0 g a.i.) during spring. Subterranean populations can be controlled with granules of dimethoate (15 g a.i.), aldicarb (5.0 g a.i.) or carbofuran (3.0 g a.i.). Aerial populations are controlled by autumn sprays of fenitrothion + dichlorvos + demeton-methyl (0.05%), vamidothion (0.025%), phosophamidon (0.035%) or dimethoate (0.03%). Banding of the trunk base with granules has been found useful in reducing reinfestation by checking the first instar nymphs, which migrate between the aerial and subterranean parts. Resistant root stocks of the ‘M.M.’ series are recommended against the pest. 相似文献
94.
95.
In this work, a series of fibrous electrets was prepared by applying electrostatic charge onto a polypropylene nonwoven fabric using corona charging process. The charging process parameters were systematically varied and their effects on charge decay were examined. A double exponential function composed of two exponentials of very different characteristics explained the charge decay characteristics very well. It was hypothesized that two charges of different nature were present in corona-charged fibrous electrets. One of the charges could be ascribed to deposition of ions onto the electret surface and the other charge could be attributed to internal polarization caused by ionic displacement. The overall charge decay could be then explained by the quick decay of the surface charge in addition to the slow decay of the bulk charge. The slow-decay component was found to contribute more to the overall charge decay with respect to a change in applied voltage. With a decrease in applied voltage, the contribution of the slow-decay component was increased. The rate of quick-decay component as well as the rate of slow-decay component was found to increase with the increase in applied voltage. With respect to a change in charging time, the quick-decay and slow-decay components were found to contribute almost equally to the overall charge. This was also true with respect to a change in distance between electrodes, except at a very high distance. With an increase in charging time, the rate of quick-decay component as well as the rate of slow-decay component started decreasing till the minimum values were obtained and increased thereafter. A similar observation was made on the role of distance between electrodes in determining the rate of quick-decay as well as the rate of slow-decay components. 相似文献
96.
This report describes the lesions seen in an extremely weak and emaciated adult male loggerhead turtle (Caretta caretta) found stranded near Perth, Western Australia. Blood collected from a dorsal cervical sinus immediately prior to euthanasia demonstrated severe anaemia, markedly elevated plasma concentrations of creatinine kinase (2263 U/L), alkaline phosphatase (58 U/L), urea (18.1 mmol/L) and hypoglycaemia (glucose 0.7 mmol/L). Necropsy examination demonstrated a severe chronic osteoarthritis of the right shoulder joint with marked remodelling of the glenoid fossa, coracoid, scapula and humerus. There was marked synovial effusion and periarticular fibrosis. Cytological examination and culture of synovial fluid failed to demonstrate an infectious agent. Other findings were low numbers of trypanorhynch cysts present on the surface of the liver and numerous spirorchid eggs in the attached mesentery. Several large and small spirorchid flukes were present in the heart and there was a localised endarteritis in the left aortic arch associated with this infection. Numerous nematode eggs and at least three species of spirorchid eggs were seen microscopically in faeces collected from the terminal colon. The pathogenesis and significance of these lesions is discussed. 相似文献
97.
This study presents the results of an analysis that identifies factors important to veterinary students in making a lifetime commitment to a particular career area. Using an importance-performance framework, the study evaluated 28 veterinary career attributes. Results indicate that to develop greater lifetime commitment among students, careers in food-supply veterinary medicine need to improve in the areas of health care and retirement benefits, free time available for family, opportunities to become authorities in the field, opportunities for advancement, and more contact with peer veterinarians. 相似文献
98.
Summary Pearl millet (Pennisetum glaucum (L.) R. Br.) hybrids based on the A1 cytoplasmic-nuclear male-sterile (CMS) lines are more susceptible to smut (Tolyposporium penicillariae Bref.) than open-pollinated varieties. Seventy eight pairs of hybrids, made onto male-sterile (A) lines and their counterpart maintainer (B) lines, were evaluated to examine the effects of male sterility and genetic resistance of parental lines on the smut severity of hybrids. The A-line hybrids had higher smut severity and lower selfed seedset than the counterpart B-line hybrids, indicating that it is the CMS-mediated male sterility rather than the A1 cytoplasm per se that caused greater smut severity of A-line hybrids. However, with the use of resistant parental lines even male-sterile hybrids of A-lines, in several cases, were as resistant as some of the highly resistant male-fertile hybrids of B-lines. It would be possible to produce smut resistant hybrids (< 10% severity) on A-lines, albeit in low frequency, even if only one parent of a hybrid were resistant. However, the probability of producing such hybrids would be higher when both parents were resistant to smut. Thus, improvement in smut resistance of parental lines and fertility restoration ability of pollinators would provide the most effective genetic approach to smut disease management in hybrids.Submitted as JA No 1737 by the International Crops Research Institute for the Semi-Arid Tropics (ICRISAT). 相似文献
99.
Summary High ergot (Claviceps fusiformis Loveless) susceptibility of pearl millet (Pennisetum glaucum (L.) R. Br.) hybrids has often been associated with the A1 cytoplasm of male-sterile lines (A-lines). To understand the underlying basis of this association and to examine the prospects of breeding ergot-resistant hybrids, we evaluated 56 hybrids and their 15 parental lines for ergot reaction and selfed seedset for 2 years in disease nurseries at ICRISAT Asia Center. Hybrids were made by crossing seven pollen parents (2 susceptible and 5 resistant) onto two resistant and two susceptible A-lines, and their four corresponding maintainer lines (B-lines). A-lines had no selfed seedset while B-lines had 32–75% selfed seedset. Hybrids of A-lines had significantly less selfed seedset than the hybrids of the corresponding B-lines. The reduced seedset of A-lines and their hybrids, however, was not always accompanied by significantly higher ergot susceptibility. Highly resistant hybrids were obtained where both A-lines and pollen parents were highly resistant, regardless of male fertility levels of the hybrids. Thus, although the A1 cytoplasm, by its reduction of male fertility, had a large and significant effect in increasing ergot severity of hybrids, the contribution of nuclear genetic factors of female parents was about 1.8 times larger than that of the cytoplasm.Submitted as JA No. 1776 by the International Crops Research Institute for the Semi Arid Tropies. 相似文献
100.
Sharma Umesh Bhardwaj Daulat Ram Sharma Sunny Sankhyan Neeraj Thakur Chaman Lal Rana Neerja Sharma Subhash 《Agroforestry Systems》2022,96(5-6):925-940
Agroforestry Systems - Agroforestry as a smart agriculture practice has started to get global attention nowadays. The present investigation is based on bamboo-ginger intercropping research carried... 相似文献