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31.
夏大豆亩产262.1kg生理指标研究 总被引:4,自引:1,他引:3
研究了夏大豆中油-89D亩产262.1kg各项生理指标:叶面积系数,开花期、结荚期、鼓粒期分别为3.98、5.80、4.91;总光合势18.2万m^2·日,平均净光合生产率4.81g/m^2·日,氮磷总积累量分别为22.28kg和3.13kg,每生产100kg籽粒需吸收氮8.50kg,磷1.19kg,总干物质积累876.47kg,粒茎比0.51,经济系数0.30。 相似文献
32.
A field experiment was conducted during the winter seasons of 1992–93 and 1993–94 at Anand to study the effect of FYM, nitrogen and source of fertilizer on growth and yield of mustard [ Brassica juncea (L.) Czernj & Cosson]. The results showed significant variation in leaf area index (LAI), crop growth rate (CGR), dry matter production and seed yield. The direct effect of farmyard manure (FYM) was conspicuous in improving the growth of mustard. FYM application at 10 tonnes ha−1 significantly increased the LAI, CGR and dry matter accumulation per plant at almost all the stages during first year study (1992–93) and in pooled analysis. Similarly, nitrogen application registered maximum LAI, CGR at 75 kg level and RGR and NAR at 50 kg level at almost all the during both years. Sulphur carrying source (Ammonium sulphate plus single super phosphate) increased all stages growth characters. Maximum dry matter accumulation per plant and seed yield were recorded with highest levels of FYM (20 tonnes ha−1 ), N (75 kg ha−1 ) and source having S. Seed yield was strongly associated with LAI and dry matter accumulation per plant at all the stages. 相似文献
33.
进一步探讨了制定科研评价体系的原则、方法等,并结合目前我国研究型大学的实际情况初步提出了一套科研评价指标体系。 相似文献
34.
春小麦优良变异类型的选择参数—协调指数 总被引:1,自引:1,他引:0
用分形理论的思想 ,对小麦分离与不分离群体内各单株性状组合特征进行系统分析 ,在不改变性状表达程度与群体分布状态的前提下 ,根据各单株的每一性状占各自群体最大值的比例数 ,及各比例数大小序号 ,求二者间双对数的回归斜率 ,作为该单株性状组合的协调指数。结果表明 ,该指数小 ,表示本单株各性状在表达程度上接近 ,说明性状间关系比较协调 ,否则即不协调。 相似文献
35.
36.
为了探讨东方蝾螈在人工养殖效果评估方面 ,在确定屠宰或捕捞的大小与时间的适宜度方面 ,在生理、病理分析时 ,在治疗时间和用药量等诸方面 ,都达到取材时期的合理性问题 ,测定了东方蝾螈的身型指数 ,并初步建立了回归方程Y =- 2 5 0 +0 .6 2X1 ,并对相关数据的处理方法进行了探讨。 相似文献
37.
Ultrasonographic determination of resistive index and graft size for evaluating clinical feline renal allografts. 总被引:1,自引:0,他引:1
Chad W Schmiedt Fern A Delaney Jonathan F McAnulty 《Veterinary radiology & ultrasound》2008,49(1):73-80
Ultrasonographic examination is a commonly employed technique for postoperative renal allograft evaluation after transplantation. Allograft size and resistive index (RI) are two objective ultrasonographic measures that may help establish a diagnosis and direct postoperative management for grafts with suboptimal function but their diagnostic efficacy has not been evaluated in clinical veterinary patients. Results of 69 feline renal transplant ultrasonographic examinations and RI determinations were studied. Based on clinical parameters at the time of the ultrasonographic examination, patients were grouped into six clinical/functional categories including evaluations of clinically normal grafts, delayed graft function, ureteral obstruction, uroabdomen, graft thrombosis, and rejection. RI, graft size (length, cross-sectional area, and volume), cyclosporine A whole blood trough concentration, Doppler blood pressure, creatinine concentration, and days from transplantation were compared between these categories and associations with each other were examined. RI was of little value in differentiating among the clinical categories with the exception of graft thrombosis. Graft volume and time from transplantation were significantly greater in grafts with signs of rejection and ureteral obstruction compared to clinically normal ultrasound examinations. Graft volume, cross-sectional area and length were generally associated. Cyclosporine A blood concentrations was associated with RI in both the pooled data and in the delayed graft function category. These results indicate RI should be used only as part of a larger clinical picture and in light of other factors including cyclosporine A concentration and the timing of the study relative to the implantation surgery for the diagnosis of postoperative transplantation complications. Graft volume may provide a more sensitive, albeit, nonspecific, indicator of allograft dysfunction. 相似文献
38.
In-Chul Park Hye-Sun Lee Jong-Taek Kim So-Jeong Nam Ran Choi Ki-Seok Oh Chang-Ho Son Changbaig Hyun 《Journal of veterinary science (Suw?n-si, Korea)》2008,9(4):415-419
Renal length, height, width, resistive index (RI), size of cortex, and medulla were determined by renal ultrasonography in 50 healthy Korean domestic short-hair cats. In the sagittal plane, the renal length was 3.83 ± 0.51 cm (mean ± SD) in the left kidney and 3.96 ± 0.48 cm in the right kidney, whereas the renal height was 2.42 ± 0.27 cm in the left kidney and 2.36 ± 0.28 cm in the right kidney. In the transverse plane, the renal height was 2.42 ± 0.28 cm in the left kidney and 2.38 ± 0.27 cm in the right kidney, whereas the renal width was: 2.65 ± 0.35 cm in the left kidney and 2.63 ± 0.31 cm in the right kidney. In the dorsal plane, the renal length was 3.84 ± 0.53 cm in the left kidney and 3.97 ± 0.54 cm in the right kidney, whereas the renal width was 2.65 ± 0.34 cm in the left kidney and 2.66 ± 0.33 cm in the right kidney. There were no significant differences (p > 0.05) among the same structure sizes measured in different planes. In the sagittal plane, the size of the renal cortex was 0.47 ± 0.08 cm in the left kidney and 0.47 ± 0.08 cm in the right kidney, whereas of the size of the renal medulla was 0.55 ± 0.30 cm in the left kidney and 0.50 ± 0.07 cm in the right kidney. RI evaluated by pulsed wave Doppler sonography was 0.52 ± 0.05 in the left kidney and 0.55 ± 0.05 in the right kidney. The actual renal dimensions determined by gross examination were not statistically different from those determined by ultrasonography. Furthermore the renal dimensions and RI were statistically correlated to the body weight of cats. 相似文献
39.
云锦杜鹃的耐碱反应 总被引:2,自引:1,他引:1
在循环型底面潮水式灌施营养液栽培系统中,对云锦杜鹃3年生实生苗进行了营养液pH4.5,5.5,6.5,7.5和8.5处理。结果表明,以植株地上和地下部干、鲜样质量为指标,营养液pH7.5的环境较为适合,而pH8.5处理不适宜云锦杜鹃的营养物质积累,即干、鲜样质量偏低,在其它的低pH处理中该指标均表现为中等水平;叶片叶绿素含量和光合效率随pH值的升高呈现出较不明显的下降趋势;根系与叶片的营养元素含量没有明显变化,除P之外,所有被测定的矿质营养元素在5个不同的pH处理中均而无明显差异。云锦杜鹃有一定的耐碱性,而且对微量元素没有特别的要求。 相似文献
40.
对采自四川及重庆地区不同采集地的26份鹅观草(Roegneria kamoji Ohwi)材料的24个形态学性状进行了观察分析.结果表明:该物种在形态学上具有丰富的遗传多样性(H′=1.955).遗传多样性指数分析表明,遗传多样性主要集中在材料内(64.48%),材料间的遗传变异为35.52%.从单份材料上看,鄷都新城材料具有最高的遗传多样性(H′=1.382).聚类分析将26份材料分为4类,聚类结果与其地理分布和采集生境存在一定的关系.主成分分析表明:穗节节间长、第2颖长、外稃芒长、花序长、旗叶宽、外稃宽和小穗小花数7个性状是解释川渝地区野生鹅观草多样性的重要性状,支持聚类结果.还探讨了鹅观草的保护及其利用. 相似文献