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991.
对福建省24种主要栽培的棕榈科植物病害种类进行系统调查,采集病害标本,通过症状观察和病原鉴定,确诊了22种病害;其中,帚梗柱孢霉(Cylindrocladium sp.)叶斑病、刀孢菌(Clas-terosporium sp.)叶斑病、鱼尾葵(Caryota ochlandra)小卵孢菌(Ovularia sp)叶斑病和射盾孢菌(Actinopelte sp.)叶斑病是国内棕榈科植物新发生的4种病害;明确了华盛顿棕(Washingtonia robus-ta)镰刀菌(Fusarium spp.)立枯病等9种病害是福建省棕榈科植物发生的主要病害,为棕榈科植物病害的防治和深入研究提供了重要依据。 相似文献
992.
[Objective] The experiment aimed to study the difference of water physiology of male and female Ginkgo biloba L. for discussing the strategy of water utilization as well as the important role of this difference during evolution process. [Method] The stem sap flow, stomatal conductance(Gs), transpiration rate(Tr) and water use efficiency (WUE) of male and female Ginkgo biloba L. were comparatively studied. [Result] The day-night processes of flow on male and female Ginkgo biloba L. were similar. The flow on male and female Ginkgo biloba L. in day were almost same while the flow at night on male Ginkgo biloba L. was bigger than that on female Ginkgo biloba L. The Tr and Gs of male and female Ginkgo biloba L. were high in morning and at night but low at noon ,while Tr and Gs of female Ginkgo biloba L. in morning and at night were higher than these of male Ginkgo biloba L. at the same time point. However, these indexes of female plant were lower than these of male plant from 11:00 to 14:00. WUE changing trends of male and female Ginkgo biloba L. were similar, while average water utilization rate of female Ginkgo biloba L. was slightly lower than that of male Ginkgo biloba L. [Conclusion] Compared with other companion plants, water physiology of male and female Ginkgo biloba L. had strong homoplasy. The phenomenon might be a survival strategy of dioecious plants under long term evolutionary pressure. 相似文献
993.
铝对茶树叶片抗氧化系统的影响 总被引:1,自引:0,他引:1
以茶树幼苗为材料,研究不同浓度铝处理培养基(沙)下,茶树叶片抗氧化系统中保护酶活性的变化.结果表明:施铝的茶树叶片过氧化氢酶(CAT)、抗坏血酸过氧化物酶(APX)、愈创木酚过氧化物酶(POD)活性显著高于不施铝的,而SOD活性却显著低于不施铝的.随着供铝浓度的增大,茶树叶片SOD、APX、CAT、POD均无显著变化.说明抗氧化酶活性的变化能较好的反映出茶树缺铝状况和适量铝可以促进茶树生长的情况. 相似文献
994.
研究不同寄主植物对三角新小卷蛾(Olethreutes leucaspis Meyrick)取食、生长、发育及存活的影响,组建三角新小卷蛾实验种群生命表.结果表明:在25℃温度下,采用荔枝、龙眼、莲雾、芒果、柑橘饲喂三角新小卷蛾的发育历期分别为20.74、18.17、23.41、23.23、29.0 d.在荔枝、龙眼上该虫幼虫和蛹的存活率较高.三角新小卷蛾在荔枝、龙眼、莲雾、芒果、柑橘上的内禀增长力(rm)分别为0.185 2、0.161 1、0.134 8、0.134 7和0.112 8.均大于0.种群趋势指数(I)分别为60.80、53.76、36.10、30.60和49.00,均大于1,该虫种群呈增长趋势.综合比较5种寄主植物,三角新小卷蛾的最适宜寄主植物是荔枝和龙眼. 相似文献
995.
Kunihiko Hamagami Bui Quoc Lap Ken Mori Yasumaru Hirai 《Paddy and Water Environment》2009,7(3):187-195
The attenuation of heat flux at the water surface with aquatic plants was examined by hydraulic experiments to consider the
influence of aquatic plants on the magnitude of thermal disturbance in the closed water body. First of all, the experiment
measuring temperatures on surface of leaf revealed the thermal conductivity of the leaf which is peculiar physicality of each
aquatic plant. Then, the hydraulic experiment examined attenuation of the underwater illuminance and the heat flux in the
covered part which depending on the kind and the luxuriant density of the aquatic plants. As the result, it is clarified that
the attenuation rate of the illuminance is large in the plant with a thick leaf, and that the heat flux at the water surface
and the developmental velocity of the mixed layer decreased when the luxuriant density of the aquatic plants increased. 相似文献
996.
W. Y. Wang Q. J. Wang Ch. Y. Wang H. L. Shi Y. Li G. Wang 《Land Degradation \u0026amp; Development》2005,16(5):405-415
Large‐scale grassland rehabilitation has been carried out on the severely degraded lands of the Tibetan plateau. The grasslands created provide a useful model for evaluating the recovery of ecosystem properties. The purposes of this research were: (1) to examine the relative influence of various rehabilitation practices on carbon and nitrogen in plants and soils in early secondary succession; and (2) to evaluate the degree to which severely degraded grassland altered plant and soil properties relative to the non‐disturbed native community. The results showed: (1) The aboveground tissue C and N content in the control were 105·97 g m−2 and 3·356 g m−2, respectively. The aboveground tissue C content in the mixed seed treatment, the single seed treatment, the natural recovery treatment and the severely degraded treatment was 137 per cent, 98 per cent, 49 per cent and 38 per cent, respectively, of that in the control. The corresponding aboveground tissue N content was 109 per cent, 84 per cent, 60 per cent and 47 per cent, respectively, of that in the control. (2) Root C and N content in 0–20 cm depths of the control had an average 1606 g m−2 and 30·36 g m−2, respectively. Root C and N content in the rehabilitation treatments were in the range of 26–36 per cent and 35–53 per cent, while those in the severely degraded treatment were only 17 per cent and 26 per cent of that in the control. (3) In the control the average soil C and N content at 0–20 cm was 11 307 g m−2 and 846 g m−2, respectively. Soil C content in the uppermost 20 cm in the seeded treatments, the natural recovery treatment and the severely degraded treatment was 67 per cent, 73 per cent and 57 per cent, respectively, while soil N content in the uppermost 20 cm was 72 per cent, 82 per cent and 79 per cent, respectively, of that in the control. The severely degraded land was a major C source. Restoring the severely degraded lands to perennial vegetation was an alternative approach to sequestering C in former degraded systems. N was a limiting factor in seeding grassland. It is necessary for sustainable utilization of seeding grassland to supply extra N fertilizer to the soil or to add legume species into the seed mix. Copyright © 2005 John Wiley & Sons, Ltd. 相似文献
997.
998.
999.
在25℃的室内条件下,测定了豇豆、茄子、甘蓝、芹菜、黄瓜、茼蒿、菜豆、西葫芦等寄主植物对南美斑潜蝇生长发育的影响.结果表明,不同寄主植物对南美斑潜蝇各虫态发育历期和存活率有显著的影响.南美斑潜蝇在选择性强的西葫芦和菜豆上发育快、存活率高,而在选择性差的甘蓝上发育慢、存活率低. 相似文献
1000.
设泥炭栽培、水苔藓栽培和地栽3种处理,对再力花、海寿花、溪荪和轮叶石胡荽在3种基质栽培处理下的适应性进行了比较.结果表明:3种处理下,再力花、海寿花和轮叶石胡荽的植株地上部、地下部生物量均以地栽处理最高,植株根冠比均以地栽处理最低;溪荪在3种处理下的适应性没有表现出明显差异;4种植物在3个处理下的根系活跃吸收面积率变化趋势相似,基本在40%~50%波动,没有明显差异;4种植物在泥炭栽培和水苔藓栽培基质下都有一定的适应性. 相似文献