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81.
《Communications in Soil Science and Plant Analysis》2012,43(6):621-628
Abstract Cavity spot incidence on sixteen samples of carrots from four fields was found to be correlated with soil ammonium (r = + .78***) and pH (r = ‐ .63**). The calcium concentration in the carrots related to soil ammonium (r = ‐ .65**), but not to cavity spot incidence. Soil nitrate and ammonium were positively associated with each other (r = + .63**), and their ratio (NH4/NO3) was very highly correlated with exchangeable manganese (r = + .93***) suggesting that anaerobicity was present. 相似文献
82.
J. L. Snider D. M. Oosterhuis E. M. Kawakami 《Journal of Agronomy and Crop Science》2011,197(3):228-236
Although photosynthetic thermotolerance has been investigated extensively in cotton leaves, reports on the biochemical influence of the pistil in promoting fertilization thermostability are limited. To evaluate the effect of temperature, genotype, and exogenous calcium application on fertilization and pistil biochemistry in cotton, thermosensitive (cv. ST4554 B2RF) and thermotolerant (cv. VH260) plants were grown under control (30/20 °C) or high‐temperature (38/20 °C) conditions during flowering, and exogenous CaCl2 was applied to flowers 1 day prior to anthesis. Measured pistil parameters included fertilization efficiency; protein concentration; glutathione reductase, superoxide dismutase (SOD) and NADPH oxidase activities; and ATP and calcium levels. Exogenous calcium had no effect on reproductive thermostability due to poor calcium uptake under high temperature. High temperature resulted in a 19.2 % decline in fertilization efficiency for ST4554 but no change in fertilization efficiency for VH260 relative to optimal temperature conditions. Pre‐stress glutathione reductase and SOD activities were higher in VH260 than ST4554 pistils, and calcium and ATP content were higher in VH260 than ST4554 pistils. It was concluded that pre‐stress antioxidant enzyme activity, ATP and calcium content of the pistil may be associated with reproductive thermotolerance in cotton. These findings should be confirmed in future experiments with a larger number of cultivars. 相似文献
83.
对我国东北农牧交错带内小尾寒羊集群放牧生态系统中5、7、9月钙、磷元素的营养状况进行了分析。结果表明:牧地土壤中钙、磷元素的总平均含量分别为1.46%、178.88μg/g;小尾寒羊2种主食牧草中钙、磷元素的总平均含量分别为0.39%、256.26μg/g;小尾寒羊羊毛中钙元素的总平均含量为2111.45μg/g;小尾寒羊羊血中钙、磷元素的总平均含量分别为69.65μg/g、10.21μg/g;小尾寒羊羊骨中钙、磷元素的总平均含量分别为4.44%、2.45%。据此认为,在该交错带集群放牧的小尾寒羊不会发生钙缺乏症或中毒病,但可能发生磷缺乏症。 相似文献
84.
高钙饲粮对青年蛋鸡血清一氧化氮浓度和抗氧化功能的影响 总被引:1,自引:0,他引:1
本试验旨在研究高钙饲粮对青年蛋鸡血清一氧化氮(NO)浓度和抗氧化功能的影响。将 35日龄 100羽伊沙蛋鸡随机均分为对照组(含钙 1.00%)和高钙组(含钙 3.78%),每组 5个重复,每个重复 10羽。每天观察鸡的精神状态、食欲和粪便情况。在饲喂高钙饲粮第 0、8、16、24和 32天时,分别测定 2组鸡的血清中 NO浓度和丙二醛含量及抗氧化酶系统的变化。结果表明:1)高钙饲粮能引起青年蛋鸡长期腹泻,在饲喂高钙饲粮的第 8天就发生高血钙症。2)与对照组相比,高钙组在饲喂高钙饲粮第 8天和第 16天血清 NO浓度无显著变化(P>0.05),第24天和第 32天显著升高(P<0.05);第 8天和第 24天血清超氧化物歧化酶活性、总抗氧化能力无显著变化(P>0.05),第 16天显著升高(P<0.05),第 32天显著降低(P<0.05);第 8、16、24天血清丙二醛含量无显著变化(P>0.05),第 32天显著升高(P<0.05);第 24天和第 32天黄嘌呤氧化酶活性有升高趋势(P>0.05)。结果提示,饲喂高钙饲粮可导致青年蛋鸡发生长期腹泻,引起高血钙症,导致其机体内自由基的产生与清除的动态平衡遭到破坏,使自由基的产生远远超出清除能力。 相似文献
85.
86.
《Communications in Soil Science and Plant Analysis》2012,43(10):891-897
Abstract Soil tests should produce data useful for making accurate lime and fertilizer recommendations aimed at optimizing chemical conditions for plant growth or providing available nutrient levels sufficient for maximum yields. In order to attain these objectives, we believe, quicktest‐computed rates have to be made equivalent to actual values through a regression adjustment. Although it may not be most desirable to use this adjustment for each new population of soils, it may be worse to try to use a function derived from one group of soils on a second group not well represented by the first. 相似文献
87.
王进龙 《青海畜牧兽医杂志》2012,42(2):20-20
对65只白唇鹿在补饲过程中添加速补钙磷,结果表明补饲过程中添加速补钙磷的试验组与对照组相比,对白唇鹿异食癖,提高鹿茸产量、降低鹿软骨病骨质疏松、瘫痪等作用显著。平均每只鹿鹿茸产量增加139.5g。鹿软骨病、瘫痪下降1.48%、异食癖发病率降为零。鹿羔月体重平均增2.5kg。 相似文献
88.
The bamboo vinegar was used to produce organic calcium,and different concentrations of NaCl,CaCb and organic calcium solutions as deicer were sprayed evenly on the potted Cymbidium ensifoiium and collected soil, and the growth of C.ensifoiium was observed everyday,and the physical and chemical properties of soil were analyzed.The results indicate that all the 3 types of salt solutions had certain influence on C.ensifolium,while the organic calcium had less effect on C.ensifolium than NaCl and CaCl2,and both of NaCl and CaCl2 had little effect on the pH of soil while organic calcium increased greatly the pH of soil,and the organic matter and cationic exchange capacity of soil reduced,and the content of total N, P in soil also reduced while the apparent content of total K in soil increased.By above comparison,the effect of organic calcium made by bamboo vinegar on C.ensifolium and soil was less than that of NaCl and CaCl2,in addition smaller the concentration of salt solution was,less the effect of salt solution on C.ensifoliumand soil was. 相似文献
89.
C. R. Wilson † J. A. deLittle J. A. L. Wong P. J. Schupp L. J. Gibson 《Plant pathology》2005,54(3):393-400
The use of soil-surface applications of finely powdered calcium hydroxide (Ca(OH)2) to inhibit Sclerotinia minor sclerotial germination and infection at the collar region of lettuce plants is described. In the laboratory, a pH > 8·0 reduced sclerotial germination of the three S. minor isolates tested. In the glasshouse, surface applications of 2–10 t Ca(OH)2 ha−1 raised the pH of the top 1–2 cm of a duplex sandy loam soil above 8·5 for at least 8 weeks without affecting soil pH within the transplant root zone. There was a linear relationship between the rate of Ca(OH)2 applied and disease control, with complete disease suppression at 10 t Ca(OH)2 ha−1. In field trials on two soil types (duplex sandy loam, pH 6·0; and red ferrosol, pH 6·9), a rate of 2·5 t Ca(OH)2 ha−1, maintained soil-surface pH above 8·5 for 1–3 weeks and provided up to 58% reduction in lettuce drop. Application of polyvinyl alcohol (a soil-conditioning polymer) over the Ca(OH)2 layer appeared to reduce Ca(OH)2 loss by wind, but did not improve retention of raised soil-surface pH or disease suppression. Ca(OH)2 treatment gave similar disease control to the industry standard treatment of a procymidone-based fungicide seedling drench. A combined treatment of Ca(OH)2 and fungicide drench gave greater control than either individual treatment, and equivalent control to fungicide drench and three procymidone foliar sprays, offering integrated management options. The use of soil-surface-applied Ca(OH)2 with fungicides, rotation and drip irrigation offers an opportunity for enhanced and sustainable control of lettuce drop. 相似文献
90.
蛇床子素可抑制小麦赤霉病菌菌丝生长干重;含有14C标记的葡萄糖培养基中培养小麦赤霉病菌,以100 μg/mL蛇床子素处理,其菌体内14C放射强度比对照降低43%,表明蛇床子素能抑制小麦赤霉病菌对葡萄糖的吸收;以100 μg/mL蛇床子素处理小麦赤霉病菌12 h,菌体内总钙含量仅为对照的60%,表明蛇床子素能抑制菌体对钙的吸收;蛇床子素处理对β-1,6-葡聚糖酶活性没有显著影响;离体条件下,蛇床子素能抑制小麦赤霉病菌三磷酸腺苷(ATP)酶活性。 相似文献