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KANG Liang LIANG Qiong-yue JIANG Qiang YAO Yi-hua DONG Meng-meng HE Bing GU Ming-hua 《农业科学学报》2020,19(4):965-974
As one of the top three tuber crops of the world, cassava is a staple food and feed crop for tropical and subtropical regions. Because of its high drought resistance and tolerance to nutrient deficiency, cassava is usually cultivated on hilly areas that are nutrient-poor. Nitrogen(N) is one of the significant factors affecting cassava yield. A double factorial(N level×genotypes) split-plot field experiment was conducted to analyze differences in yield and N accumulation of 25 cassava genotypes under low-N conditions to screen for cassava genotypes with high-N efficiency. The two-year field experiment showed that cassava yield and N accumulation are determined by specific genotypes, soil N levels, and year. Among these factors, soil N levels are the main factors that are responsible for differences in cassava yield. When yield and relative N accumulation under low-N conditions were used as screening markers, we identified an efficient and responsive genotype(SC10), and two inefficient and non-responsive genotypes(SC205 and GR5). The efficient and responsive genotype and the inefficient and non-responsive genotype can be used as study materials to further reveal the mechanisms for high-N efficiency in cassava. 相似文献
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4种药剂防治马铃薯地下害虫田间药效试验 总被引:1,自引:0,他引:1
为探明德州地区马铃薯地下害虫发生为害情况,筛选出防治马铃薯地下害虫安全且有效的药剂,在马铃薯收获时对马铃薯地下害虫的发生情况进行了调查;采用马铃薯块茎拌种(药液与块茎质量比为1∶10)的方式,比较了4种药剂对马铃薯地下害虫的田间防效,以期筛选出对马铃薯地下害虫防效好且对马铃薯安全的药剂种类及其适宜用量。结果表明:德州地区马铃薯地下害虫种类主要有蛴螬、金针虫和地老虎。35%丁硫克百威种子处理干粉剂用量10 mL/kg处理对蛴螬、金针虫和地老虎防效均较高,达到80%左右;对马铃薯茎块的保护率最高,为56.54%。3%阿维菌素微囊悬浮剂用量10 mL/kg处理防效较差,在50%左右;对马铃薯茎块的保护率最低,为32.90%。各药剂处理的马铃薯叶色、长势等均正常,未观察到药害现象发生。建议使用35%丁硫克百威种子处理干粉剂100倍液拌种防治马铃薯地下害虫。 相似文献
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CHEN Yu-si HAN Bing ZHENG Lu CAI Shuang TANG Lei YANG Yi GUO Yi-xin LIANG Cai ZHAO Jin-you YANG Ting YANG Qin XIE Ru-jia 《园艺学报》2020,36(5):847-853
AIMTo investigate the effects of calpain-2 and autophagy-related protein 5 (Atg5) on apoptosis of BRL-3A rat normal liver cells during endoplasmic reticulum stress (ERS) induced by dithiothreitol (DTT). METH?ODS: BRL-3A cells were treated with DTT at 2.0 mmol/L for 0, 6, 12 and 24 h to induce ERS. Real-time cell analysis (RTCA) was used to measure the effect of DTT on BRL-3A cell proliferation. Apoptosis and cell cycle distribution were analyzed by flow cytometry. The mRNA expression of calpain-2 and Atg5 was detected by real-time PCR. The protein levels of calpain-2, Atg5, Atg7, Atg12 and microtubule-associated protein 1 light chain 3 (LC3) were determined by Western blot. The interaction between calpain-2 and Atg5 was investigated by co-immunoprecipitation (Co-IP). RESULTSThe proliferation of BRL-3A cells treated with DTT was significantly inhibited. The apoptosis of BRL-3A cells was significantly increased after DTT treatment for 6, 12 and 24 h as compared with 0 h group (P <0.05). The cell cycle was arrested in G1 phase after DTT treatment (P <0.05). After DTT treatment for 6, 12 and 24 h, the mRNA expression of calpain-2 and Atg5 in the BRL-3A cells was significantly increased as compared with 0 h group (P <0.05). The protein levels of calpain-2, Atg12 and Atg7 in the cells treated with DTT for 6, 12 and 24 h were significantly higher than those in 0 h group, and the ratio of LC3-II/LC3-I was also significantly higher than that in 0 h group, while Atg5 expression was significantly lower than that in 0 h group (P <0.05). The results of Co-IP found that the anti-calpain-2 antibody precipitated Atg5 protein from the cell lysates, and the anti-Atg5 antibody also precipitated calpain-2 from the cell lysates, which confirmed the interaction between calpain-2 and Atg5. CONCLUSION Calpain-2 may participate in ERS-induced hepatocyte apoptosis by interacting with Atg5. 相似文献
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Gou Xiaomei Cai Yan Wang Changquan Li Bing Zhang Yi Tang Xiaoyan Shen Jie Cai Zehui 《Journal of Soils and Sediments》2020,20(3):1371-1382
Journal of Soils and Sediments - Phosphorus (P) fertilizer has been applied in regions with red soils to ensure high crop yield. However, the supply of bioavailable P for crop plants is... 相似文献
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