多功能高分子植物生长调节剂在干旱区玉米生产上的试验效果初报

报道了以观测记录和拍照方式研究多功能高分子植物生长调节剂对玉米生长和繁殖的影响结果,分别用玉米生长、结实和产量指标、玉米品质指标以及经济效益指标与对照比较以评定试验效果。结果显示,施用试剂有利于玉米的营养和结实生长,使玉米产量增加11.06%、品质有所改善(试验组玉米粗蛋白和粗脂肪含量有所提升),经济效益有所提高,仅仅考虑增产就净增产值607.95元/hm2。

Effects of Enhanced Ultraviolet Radiation-B on Maize in Arid Regions of Middle-high Elevation

[Objective] The experiment aimed to explore the influence of enhanced ultraviolet radiation-B on maize in arid regions of middle-high elevation for correct assessing the influence of enhanced ultraviolet radiation-B on maize and providing scientific reference to make proper countermeasures. [ Method] The location test in field and lift lamp of UV-B were used to observe the changes of maize height, leaf area and number of green leaves under influences of different UV-B radiation. [ Result] In arid regions of middle-high elevation, enhanced ultraviolet radiation-B could dwarf maize plant, decrease leaf area, decline number of green leaves and yield. The reason of decreasing leaf area was that enhanced ultraviolet radiation-B shortened leaf length and leaf width while the reason of declining yield was that yield components were all negatively influ- enced and with the increase of ultraviolet radiation-B, the yield declined dramatically. [ Concluslonl The result of this experiment would be good for maize production in arid regions of middle-high elevation.

Discussion Abiotic Stress Tolerance and Corresponding Strategies for Maize Breeding in Southwest Region of China

Maize is an important food crop, as well as the irreplaceable feed and industrial materials, having huge market demand in China. Southwestern region of China is the third largest main maize producing zone, and the frequent occurrence of abiotic stress conditions such as drought, heat, cold, wet shaded stress have severely affected the development of maize production, causing low and unstable corn yields, severely restricting the maize industry development in the southwest of China. This paper preliminarily describes the maize resistance to abiotic stresses in southwestem region of China, putting forward the countermeasures and the key research direction in the practice of breeding in order to provide reference for the cultivation of new varieties with high yield and stress resistance, and improving the levels of maize stress resistance breeding in southwestern region of China.

Influential Factors of Water Productivity of Maize in Oasis of Arid Areas——A Case Study of Linze County

[Objective] The aim was to research influential factors of water productivity of maize in oasis in arid areas. [Method] In middle reach of Heihe River in Linze County of Zhangye City, maize, a major crop in irrigated area in the oasis, was studied and nine influential factors were chosen through grey relation analysis. [Result] According to grey relation analysis, top five factors influencing water produc- tivity of maize during 1995-2009 were as follows： applied quantity of chemical fertil- izers〉labour input〉seeds〉mulch amount〉pesticide amount, which indicated that controllable factors, instead of uncontrollable ones, dominate in influence of water productivity of maize in oasis in arid areas. [Conclusion] With water resource limited, investment of controllable factors in high-efficient agricultural production should be the major strategy to improve water productivity of maize in oasis of arid areas.

Effect of Soil Drought Stress on Leaf Water Status, Membrane Permeability and Enzymatic Antioxidant System of Maize

A simulation experiment on the responses of maize (Zea mays L.) from the third leaf stage to maturity for different soil water levels (well-watered, moderately stressed, and severely stressed) was conducted by controlling irrigation and using a mobile rain shelter in a neutral loam, meadow soil to determine the effects on leaf water status, membrane permeability and enzymatic antioxidant system for different growth stages. The results indicated that drought stress relied on drought intensity and duration, with more severe drought stress creating more serious effects on maize. Compared with well-watered conditions, during the silking and blister stages moderate stress did not significantly change the relative water content (RWC) and did change significantly the relative conductivity (RC) (P < 0.05) of the leaves; however, severe stress did significantly decrease (P < 0.01) the leaf RWC and increase (P < 0.01) membrane permeability (leaf relative conductivity). Furthermore, under severe drought stress antioxidant enzyme activities declined significantly (P < 0.01) in later stages, namely for superoxide dismutase (SOD) the tasseling and blister stages, for peroxidase (POD) the milk stage, and for catalase (CAT) during the tasseling, blister, and milk stages. Meanwhile, membrane lipid peroxidation (measured as malondialdehyde content) significantly increased (P < 0.01) in all stages.