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11.
Physiological Indices and Selection of Methods on Rapid Identification for Sweet Potato Drought Resistance 总被引:1,自引:0,他引:1
ZHANG Ming-sheng TAN Feng ZHANG Qi-tang YANG Yong-hua 《中国农业科学(英文版)》2005,4(11):826-832
The relationships between the changes of relative water content (RWC), malondialdehyde (MDA) contents, superoxide dismutase (SOD) activity and free proline contents in sweet potato leaves, and drought resistant ability under different concentration of polyethylene glycol (PEG) treatment applied at rhizosphere of sweet potato seedlings were studied. A highly positive correlation between RWC and drought resistance (r =0.783, P〈0.01), a highly negative correlation between MDA contents and drought resistance (r = -0.848, P〈0.01), a highly positive correlation between SOD activity and drought resistance (r = 0.777, P〈0.01) was observed. Free proline contents in leaves was not related obviously to the sweet potato drought resistance under 25% PEG treatment. The stronger the drought resistance of variety, the less decrease of RWC and increase of MDA contents, the more increase of SOD activity. By determining these physiological indices in sweet potato leaves under 25% PEG treatment, rapid identification of drought resistant ability of different varieties can be obtained in the lab. 相似文献
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A field experiment was conducted to find out the critical physiological stages of irrigation schedules inducing better growth, physiological efficiency and seed yield potential of berseem ( Trifolium alexandrinum L., Var. S-99-1). For this purpose eight irrigation treatments were made comprised of four treatments of three irrigation (W1 , W2 , W3 and W4 ), three treatments of four irrigation (W5 , W7 and W8 ) and one treatment of five irrigation (W6 ) at various physiological stages i. e. regeneration, flower initiation, full bloom, seed initiation and advance seed development stage.
Thus based on the experimental results the physiological role of watering in berseem seed production could be discussed as:
With-holding of irrigation either at regeneration or at full bloom stage developed potential water stress in plants as indicated by high proline content of irrigation treatments — W4 , W1 and W7 ; and further brought out disturbance on the formation of carotene, synthesis of water soluble sugar and translocation of sugar towards reproductive organs during grain development stage. These stresses adversely affected the plant growth and flowering behaviour. The irrigation at seed initiation stage increased the seed yield. Continuous irrigation did not appear to be useful. Thus it can be concluded that irrigation at three critical physiological stages i. e. regeneration, full bloom and seed initiation was found to be essential for obtaining potential seed yield of berseem. 相似文献
Thus based on the experimental results the physiological role of watering in berseem seed production could be discussed as:
With-holding of irrigation either at regeneration or at full bloom stage developed potential water stress in plants as indicated by high proline content of irrigation treatments — W
14.
赵有恩 《干旱区资源与环境》1996,(2)
本文以土地详查、淤地坝普查成果为基本依据,结合典型调查,研究分析了河龙区间南片水土保持各项措施的保存率,认为在空间尺度上,分行政区给出的保存率较为真实的反映了社会环境、自然环境因素的相对作用程度及其主导关系,且有实际应用意义,据此文中进一步核实评述了该区水保措施的保存面积、措施结构及质量等。该区水保措施的状况在黄河中游干旱半干旱地区具有广泛的代表性,分析结果可作为水沙分析、水保规划、土地资源与环境评价等工作的重要参考依据。 相似文献
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G. J. Glova 《Ecology of Freshwater Fish》2003,12(4):247-253
Abstract – The interaction between brown trout ( Salmo trutta ; fork length (FL) range 255–390 mm) and inanga ( Galaxias maculatus ; FL range 55–115 mm) was tested during summer through autumn in an artificial stream consisting of a single run-riffle-pool sequence with a natural food supply. Each experimental trial lasted for 15 days, and consisted of two brown trout and 50 inanga collected fresh from a nearby stream, with each species given prior residence in four replicate tests, totalling eight trials in all. In addition, two control trials (each 10 days), with 50 inanga in each, were run. Brown trout almost exclusively occupied the pool, whereas inanga occupied all habitat types, although in different proportions, when tested with and without brown trout. The proportion of inanga in the pool was appreciably lower in the experimental trials with brown trout than in the control trials with no brown trout; prior residence had no significant effect on inanga habitat use. Mortality of inanga attributable to predation by brown trout ranged from 0 to 40% with a mean of 14.5 ± 4.7%. The results suggest that habitat use and survival of inanga populations in small streams can be adversely affected by brown trout. 相似文献
17.
XIAOLi 《东北农业大学学报(英文版)》2001,8(2):139-151
This article analyzes the importance of non-use values in the management of natural resources with a model of imperfect competition.By constucting a framework of duopolistic exploiters.the incorporation of non-use values based on self-interest and altruistic motives appears to be significant for determining the degree of inefficiency caused by the problem of common property at the non-cooperative Nash equilibrium.It is found that when the non-use value placed by the altruist exploiter is bounded by that placed by the pure selfinterest exploiter,the effect of market power is dominated by the effect of common exploitation.In this case,the exploiters‘ harvesting strategy will response in the same direction to the change of each other‘s harvesting at the non-cooperative Nash equilibrium.In contrast,when the non-use value placed by the altruist is substantially larger or smaller than that placed by the self-interest exploiter,one exploiter‘s increase in harvesting will lead to a decrease in harvesting of the other exploiter at the non-cooperative Nash equilibrium. 相似文献
18.
盐分对碱茅种子发芽影响的机制 总被引:15,自引:0,他引:15
耐碱茅种子在盐(NaCl与Na2SO4)及干旱(PEG-6000模拟)胁迫下发芽及其机制的比较研究表明,种子发芽率随溶液渗透势的降低而下降,在等渗条件下三种溶液中的发芽率次序为Na2SO4>NaCl>PEG。NaCl与Na2SO4主要通过影响种子吸水量及对膜的毒性影响发芽,根据相关及通径分析结果,其机制为:(1)溶液渗透势及Na+浓度决定的种子吸水对发芽的直接正效应(通径系数0.73);(2)溶液Na+浓度引起的膜毒性对发芽的直接负效应(-0.51);(3)种子从溶液中吸收Na使种子吸水增加对发芽的间接正效应(0.30)及使膜毒性增大对发芽的间接负效应(-0.24)。 相似文献
19.
20.
研究了叶面喷施抗蒸剂对盆栽苹果水分状态的影响。结果表明:抗旱剂一号(主要成分为黄腐酸)可明显降低树体蒸腾(最低时为对照的39.21%)、提高气孔阻力(最大时为对照的243.96%)和叶片水势(一般比对照提高0.2-0.4MPa、最大0.7MPa),并对叶温未产生明显的影响(变化一般小于1℃),有效作用期长达15d以上。在果树旱期喷施,可明显改善树体水分状态。腐殖酸效果不明显。 相似文献