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21.
双杂吨粮生理生态指标及栽培模式研究 总被引:1,自引:2,他引:1
本研究通过3年的调查与试验,阐明了不同生育期杂交稻组合在不同栽培季节,不同栽培水平下的产量形成特点及氮钾吸收特性,明确了杂交稻的穗型与生育期有一定的关系,对杂交稻需钾量是否近似常规稻这一理论问题也给予了肯定的证明.根据研究结果,提出了不同生育期杂交稻组合亩产吨粮的产量结构指标,氮钾吸收量指标及相应的生理生态指标,制订的“双季杂交水稻高产栽培模式”,实用性强,增产节支,为吨粮田的建设与推广提供了技术方案. 相似文献
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Aihong Liu Guiquan Guan Pengfei Du Huitian Gou Jun Zhang Zhijie Liu Milin Ma Qiaoyun Ren Junlong Liu Jifei Yang Youquan Li Qinli Niu Qi Bai Hong Yin Jianxun Luo 《Veterinary parasitology》2013,191(1-2):15-22
The present study developed and validated a species-specific loop-mediated isothermal amplification (LAMP) assay for the rapid detection and discrimination of two benign bovine Theileria species – T. sergenti and T. sinensis. The LAMP assay is inexpensive and easy to perform and involves a rapid reaction-the amplification can be performed in 55 min or 50 min under isothermal conditions of 61 °C or 63 °C, respectively, by employing a set of four species-specific primer mixtures. The results can be checked using agarose gels. The optimal assay conditions, under which the assay exhibited with no cross-reaction with other closely related tick-borne parasites (T. annulata, Babesia bovis, B. bigemina, B. major, B. ovata, B. U. sp., Anaplasma marginale) or between the two Theileria species of interest, was established. The assay is approximately 10-fold more sensitive than the conventional specific PCR assay. The LAMP assay was validated using DNA from 6 standard stocks in the laboratory and was evaluated for its diagnostic utility using blood samples collected from experimentally and naturally infection cattle or yaks in China. These findings indicate that this Theileria species-specific LAMP assay may have potential clinical applications for the detection and differentiation of two benign bovine Theileria species – T. sergenti and T. sinensis, especially in endemic countries. 相似文献
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磷石膏改良强酸性黄壤的效应研究 总被引:5,自引:0,他引:5
采用盆栽试验,以耐铝能力弱的高粱和强酸性黄壤为研究对象,探讨了磷石膏对强酸性环境高粱生长、养分平衡以及对土壤有效养分和交换铝的影响。结果表明,在强酸性黄壤上,由于铝毒作用,即使施足氮磷钾肥,高粱也生长不良;施用磷石膏和石灰的高粱生长正常,各生物学性状均极显著优于对照,施磷石膏高粱长势更优于施石灰者,高粱干重与磷石膏、石灰的施用量呈二次曲线变化(回归方程分别为:y=6.88 11.92x-1.65x2,R=0.983;y=6.88 6.39x-0.72x2,R=0.996),高粱株高和根长与磷石膏、石灰的施用量也呈二次曲线变化;磷石膏降低酸性黄壤铝毒、提高植物钙含量的效果略逊于石灰,在提高植物营养三要素(特别是磷、钾元素)的作用方面优于石灰,施磷石膏高粱磷、钾含量较石灰处理分别提高117.0%~200.0%和13.0%~14.8%;施磷石膏生长良好的高粱植株氮/磷、氮/钾、钾/磷比分别为6.8~7.1,1.2~1.3和5.4~5.6,比值适中、变幅小,氮/铝、磷/铝、钾/铝、钙/铝比分别是对照植株的1.9~2.0倍,5.8~6.3倍,1.8~2.1倍和2.0~2.5倍,改善和调节了高粱体内氮、磷、钾、钙养分的平衡;施磷石膏的土壤有效氮、磷、钾、钙较对照极显著增加,土壤有效磷、钾分别比施石灰提高41.8%~114.2%和59.4%~67.5%,施石灰的土壤有效磷、钾与对照差异不显著。 相似文献
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Preliminary study to evaluate the effects of dietary bile acids on growth performance and lipid metabolism of juvenile genetically improved farmed tilapia (Oreochromis niloticus) fed plant ingredient‐based diets
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A 9‐week feeding experiment was conducted to investigate the effects of dietary bile acids (BAs) on juvenile genetically improved farmed tilapia (GIFT) (Oreochromis niloticus) based on the evaluations of growth performance and parameters relevant to lipid metabolism. Each of five vegetable protein‐based diets containing BAs at a level of 0, 0.05, 0.15, 0.45 or 1.35 g/kg diet was fed to three replicates with 40 fish (8.2 g per fish). The results showed that weight gain (WG) increased significantly with the increase in BAs from 0 to 0.15 g/kg diet and then decreased significantly at a higher BA supplementation. Dietary BAs significantly reduced the crude lipid content in the whole body, muscle and liver tissue of GIFT. Fish fed diet with 1.35 g BAs/kg diet developed serious nuclear migration and vacuolization in hepatocytes. Gall bladder appeared to contain white solid and has fragile capsules. Dietary BA supplementation had significant effects on serum biochemical indices and activities of lipid metabolism enzymes in liver and intestine. In conclusion, dietary bile acid supplementation (0.15 g/kg) can facilitate the lipid metabolism and therefore promote the growth of tilapia. However, overdosed dietary BAs induced gallstone development, disrupted lipid metabolism and depressed the growth performances of GIFT. 相似文献