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51.
为合理使用低毒农药防治水稻粘虫,2015年7月在广西乐业县同乐镇和甘田镇进行25%灭幼脲悬浮剂和2.2%甲氨基阿维菌素苯甲酸盐微乳剂防治粘虫大田示范试验。结果表明:施药后17 d,核心区25%灭幼脲对粘虫的防治效果和保叶率分别为96.19%和94.73%,在培训指导农民防治示范区的防效分别为93.50%和95.10%;施药后10 d,核心区2.2%甲氨基阿维菌素苯甲酸盐对粘虫的防治效果和保叶率分别为96.61%和97.35%,在培训指导农民防治示范区的防效分别为90.07%和89.59%。25%灭幼脲和2.2%甲氨基阿维菌素苯甲酸盐处理区对粘虫的防效均要高于农民自防区。 相似文献
52.
苗后除草剂喷施时期对杂草防治及冬油菜产量和品质的影响 总被引:1,自引:0,他引:1
为了探究苗后除草剂不同施用时期对北方冬油菜田间杂草的防控效果及其对冬油菜生长、产量和品质的影响,以当地主栽甘蓝型冬油菜天油2266和白菜型冬油菜天油H614为试验材料,选用对冬油菜安全的苗后除草剂高效氟吡甲禾灵,设置4个喷施时期处理,于2018-2019年开展大田试验。结果表明,越冬后不同时期喷施苗后除草剂,甘蓝型冬油菜田间杂草总数较对照减少57.54%~92.56%,杂草总鲜重较对照降低75.40%~97.48%,第2时期(3月25日)处理产量较对照增加354.50kg/hm2;白菜型冬油菜田间杂草株防效和鲜重防效分别为55.91%~92.02%和37.17%~97.46%,产量较对照增加2.29%~16.77%。因此,在冬油菜大量返青但未封行前施用苗后除草剂,可显著防控田间杂草并增加冬油菜籽粒产量。 相似文献
53.
Zidi Jin Long Liu Cheng Xu Chunchi Yan Shuo Li Tuoyu Geng Daoqing Gong 《Animal Science Journal》2021,92(1):e13672
Goose fatty liver is a specific type of nonalcoholic fatty liver that is protected from harmful effects associated with severe steatosis. Our previous findings suggest that suppression of the complement C5 may be relevant, but the mechanism is unclear. Therefore, in this study, we first verified the expression pattern of complement genes (including C5) during goose fatty liver formation and then determined the liver fat content and fatty acid composition by high-performance liquid chromatography (HPLC), followed by selecting the differential metabolites to treat HepG2, goose and mouse primary hepatocytes, aiming to explore the mechanism of C5 and inflammation suppression in goose fatty liver. The data confirmed the suppression of complement genes (including C5) in goose fatty livers. Moreover, fat content was significantly higher in fatty liver versus normal ones, with oleic acid and palmitic acid dominantly accounting for the difference. In line with this, high concentration of palmitate led to down regulation of C5 expression in goose primary hepatocytes whereas upregulation in mouse primary hepatocytes and HepG2 cells. In conclusion, regulation on C5 expression by fatty liver related factors including high level of palmitic acid may contribute to the protection of goose liver from severe hepatic steatosis. 相似文献
54.
草地贪夜蛾幼虫龄期对自相残杀行为的影响 总被引:3,自引:0,他引:3
对群体饲养下草地贪夜蛾幼虫在不同龄期的自相残杀行为进行了比较研究,结果表明:在4种密度(5、10、20头/瓶和30头/瓶)下,不同龄期的幼虫自相残杀率差异显著,不同密度下的自相残杀行为主要集中在5龄幼虫,其自相残杀率均在5龄第2天时最高,在5、10、20和30头/瓶中分别为(14.34±3.28)%、(17.94±3.26)%、(18.21±3.47)%和(27.05±5.52)%,幼虫在5龄前的自相残杀行为并不明显。进一步测定发现,相同数量的4龄和5龄幼虫混合后在3种密度(4、10和20头/瓶)下的自相残杀率无显著差异(F=2.29,df=2,P>0.05),但随着幼虫密度的增加,死亡的4龄幼虫占总死亡个体的比例升高,而死亡的5龄幼虫所占比例下降。这说明草地贪夜蛾同一龄期的幼虫自相残杀行为具有明显的龄期依赖性,自相残杀行为主要发生在高龄幼虫间。低龄和高龄幼虫同时存在时低龄幼虫被残杀的比例较高。试验结果对于草地贪夜蛾的室内大量饲养具有一定借鉴作用。 相似文献
55.
AIM: To investigate the autophagy of human ovarian cancer SKOV3 cells induced by cepharanthine and to explore its mechanism. METHODS: The effect of cepharanthine on the viability of ovarian cancer SKOV3 cells was measured by CCK-8 assay. The SKOV3 cells were treated with cepharanthine, and then the formation of autophagosome was observed with acridine orange staining under fluorescence microscope. The protein levels of LC3, AKT, p-AKT, mTOR, p-mTOR and GAPDH in the SKOV3 cells treated with cepharanthine were determined by Western blot.RESULTS: Cepharanthine significantly inhibited the viability of ovarian cancer SKOV3 cells in a dose-dependent manner (P<0.05). The number of the intracellular acidic autophagosomes with bright red fluorescence was significantly increased after cepharanthine treatment in the SKOV3 cells. The expression of LC3-Ⅱ in SKOV3 cells was significantly enhanced after cepharanthine treatment. Furthermore, treatment with cepharanthine in the SKOV3 cells also resulted in a significant down-regulation of phosphorylated form of AKT and mTOR (P<0.01), while the total protein level was not changed. Combination of cepharanthine and 3-methyladenine resulted in a substantial decrease in the cell viability compared with using cepharanthine alone.CONCLUSION: Cepharanthine significantly inhibits the growth of human ovarian cancer SKOV3 cells and induces the autophagy, which may be correlated with down-regulation of PI3K/AKT/mTOR signaling pathway. 相似文献
56.
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58.
以湘烟5号为材料,通过盆栽试验,探讨不同浓度植物提取物对烤烟主要化学成分及致香物质含量的影响。结果表明,喷施栀子花和玉兰花汁液提取物有利于烟叶原料主要化学成分含量的改善,与对照相比,喷施处理的上部橘黄二级(B2F)和中部橘黄三级(C3F)烟叶还原糖含量分别高15.0%~21.1%和14.3%~17.7%,钾含量分别高5.7%~13.9%和7.4%~14.0%;与对照相比,喷施处理的烟叶的石油醚提取物、类胡萝卜素降解物、降解产物、茄酮、非酶棕色化反应产物、芳香族氨基酸裂解产物、新植二烯和中性致香物质总量,上部橘黄二级(B2F)烟叶分别高10.0%~20.9%、11.2%~20.9%、9.6%~20.2%、9.8%~21.1%、10.8%~22.5%、11.2%~23.0%、14.9%~24.7%和11.9%~22.1%,中部橘黄三级(C3F)烟叶分别高13.5%~24.1%、11.3%~21.0%、11.4%~20.0%、10.8%~18.7%、13.1%~21.2%、10.1%~19.1%、17.5%~27.0%和18.1%~27.6%;烟叶感官质量评价权重得分高于对照。栀子花和玉兰花汁液提取物对烟叶主要化学成分及致香物质含量的作用效果以施用量3.5~5.0g/株的处理最佳。 相似文献
59.
Frdrick G. Sunstrum Wubishet A. Bekele Charlene P. Wight Weikai Yan Yuanhong Chen Nicholas A. Tinker 《Plant Breeding》2019,138(1):82-94
We developed 178 recombinant inbred lines from a southern‐by‐spring oat population designated as “TxH.” These lines were genotyped to generate a high‐quality linkage map that resolved 6,902 markers into 21 linkage groups that matched closely with the latest hexaploid oat consensus map. Three major quantitative trait loci (QTLs) affecting heading date were found in locations that are consistent with known QTLs and candidate genes, and two other QTLs affecting heading date were found in novel locations. Five QTLs affecting plant height were found. Both sets of QTLs are responsible for transgressive segregation observed for these two traits. Four QTLs affecting resistance to crown rust, caused by the pathogen Puccinia coronata f. sp. avenae, were identified. Two of these QTLs are consistent with known clusters of rust resistance genes, while two may represent new locations of novel rust resistance genes. A complete set of SNP sequences suitable for generating markers for molecular selection is provided. 相似文献
60.
CHEN Xing-yu LUO Yin-he WANG Meng-qing CHEN Ying-ying LI Yan HUANG Kai-ling SUN Le DING Yi SUN Xuan-long 《园艺学报》2019,35(7):1268-1275
AIM:To investigate the effect of Kechuanning on airway remodeling and the protein level of p-ERK1/2 in lung tissues of asthmatic rats induced by virus. METHODS:The asthmatic rat model induced by respiratory syncytial virus was established. The experimental rats were divided into normal group, asthma model group, low dose (0.33 mL/kg), middle dose (3.0 mL/kg) and high dose (10 mL/kg) of Kechuanning groups, and PD98059 (3 mg/kg) group. The airway responsiveness of the rats was measured by animal ventilator. The pathological changes of the lung tissues were observed by HE staining. PAS staining and Masson staining were used to observe goblet epithelial cells metaplasia and airway collagen deposition. The expression of matrix metalloproteinases-9 (MMP-9) and tissue inhibitor of matrix metalloproteinase-1 (TIMP-1) in the lung tissues of the rats was detected by immunohistochemical staining. The protein levels of ERK1/2 and p-ERK1/2 were determined by Western blot. RESULTS:Compared with model group, the airway responsiveness of the rats in middle dose and high dose of Kechuanning groups was significantly decreased (P<0.01), the injury of lung tissues was significantly decreased, the goblet epithelial cells metaplasia and airway collagen deposition were significantly reduced (P<0.01), and the expression of MMP-9 and TIMP-1 in the lung tissues was also significantly decreased (P<0.01). In addition, the protein level of p-ERK1/2 in high dose of Kechuanning group was significantly decreased compared with model group (P<0.01). CONCLUSION:Kechuanning may treat asthma by regulating the expression of p-ERK1/2 in the lung tissues and improving the airway remodeling symptoms of asthmatic rats induced by virus. 相似文献