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841.
以陇蜜9号桃和千年红油桃为供试材料,利用那氏齐齐发诱导剂800倍液在3月底树液流动后灌根,以2000倍液分别于6月初果实膨大期和果实成熟前1周叶面喷施.结果表明:那氏齐齐发诱导剂能够提早果实成熟,使果个显著增大、产量增加、提高果实的可溶性固形物含量,并能改善果实着色,提高果实品质. 相似文献
842.
以黄瓜为试材,采用小区试验对比的方法,研究了滴灌和畦灌条件下不同磷素用量对秋季大棚黄瓜产量的影响,以期为提高秋季大棚黄瓜产量提供参考依据。结果表明:滴灌大棚的黄瓜生长状况明显好于畦灌大棚,商品黄瓜产量显著提高(P0.05),各阶段用水总量278.3 mm,节水达41%。畦灌条件下,不施磷肥处理黄瓜果实产量显著低于磷肥处理(P0.05);滴灌条件下,过量的磷肥施用(P2O5100 kg·hm~(-2))导致黄瓜果实产量和品质显著下降(P0.05)。由此可见,滴灌条件下合理施用磷肥能够降低水资源消耗,提高磷肥利用效率,有利于黄瓜品质和产量的提升。 相似文献
843.
为阐明甜菜单胚雄性不育系和保持系花药及小孢子发育的超微结构差异.以自育的甜菜单胚细胞质雄性不育系(CMS系)TB9-CMS和保持系(O型系)TB9-O为试验材料,在甜菜花芽分化、现蕾初期、开花初期分别进行4次花蕾取样.电子显微镜观察花药及小孢子发育过程的超微结构差异。结果表明.甜菜单胚CMS系与。型系花药和小孢子发育过程的超微结构存在明显差异。甜菜单胚CMS系花药壁产生初始期与。型系相似.但小孢子母细胞的数量较少,液泡化明显;绒毡层发育初期也形成乌氏体原始颗粒,但仅维持初始状态而停止发育:绒毡层在四分体期收缩离位,瓦解内移;小孢子母细胞形成四分体后,胼胝质壁较厚,小孢子逐渐变异开始退化。观察还发现,甜菜绒毡层细胞间以及形成四分体的胼胝质壁间有胞间连丝结构. 相似文献
844.
845.
为适应市场对优质、长果、多抗、专用型的鲜食线椒品种需求,2011年秋以SR1301为父本、SR908为母本选育的杂交一代新品种苏润001,于2018年4月23日获得了农业部非主要农作物品种登记证书,证书编号为(2018)320462。该品种平均株高100 cm,株幅87 cm,鲜椒单果质量24 g,果长32 cm,果宽1.8 cm,肉厚0.2 cm;2018年生产试验前期平均产量为26 553.2 kg/hm^2,比对照8819线椒增产34.5%,总产量为64 918.8 kg/hm^2,比对照8819线椒增产33.3%,产量突出。2015-2018年试验中,苏润001病毒病、疫病、炭疽病平均病情指数依次为3.3、7.1、7.2,比对照8819线椒分别减少24.9%、12.3%、17.0%,适合贵州省春秋保护地及露地高效栽培。 相似文献
846.
847.
DAI Pei GAO Fen GAO Hong-wei WANG Yuan FENG Gao-jie ZHANG Qin-feng BAI Rui QIN Wei-wei LI Hong SONG Xiao-su 《园艺学报》2019,35(2):212-217
AIM:To study whether homocysteine (Hcy) inhibits the expression of ATP-binding cassette transporter A1 (ABCA1) and ATP-binding cassette transporter G1 (ABCG1) by microRNA-33 (miRNA-33) signaling, and reduces the efficiency of reverse cholesterol transport (RCT).METHODS:RAW264.7 macrophages were induced by oxidized low-density lipoprotein (ox-LDL) to establish foam cell model. Oil red O staining was used to determine whether the model was established successfully. miRNA-33 mimics and miRNA-33 inhibitor were transfected into the cells by Lipofectamine 2000, and the cells were exposed to Hcy at concentration of 5 mmol/L for 24 h. The intracellular lipid droplets were observed by Oil red O staining. The expression of ABCA1 and ABCG1 at mRNA and protein levels was determined by real-time PCR and Western blot. The cellular cholesterol content was analyzed by HPLC, and effluent rate of cholesterol was detected by the method of liquid scintillation counting.RESULTS:Compared with blank control group, the lipid content in miRNA-33 mimics group was increased, and the expression of ABCA1 and ABCG1 at mRNA and protein levels was decreased (P<0.05). The intracellular cholesterol content was increased gradually (P<0.05), and the cellular cholesterol efflux rate was gradually decreased (P<0.05) in miRNA-33 mimics group. Compared with blank control group, the testing results in miRNA-33 inhibitor group were the opposition of those in miRNA-33 mimics group (P<0.05). No diffe-rence of the above indexes among blank control group, miRNA-33 mimics-NC group and miRNA-33 inhibitor-NC group was observed.CONCLUSION:Hcy inhibits the mRNA and protein expression of ABCA1 and ABCG1 through miRNA-33 signaling, and reduces the efficiency of RCT in RAW264.7 macrophage-derived foam cells. 相似文献
848.
将采自长春净月潭的野生蛹虫草进行分离,分离后的蛹虫草菌株进行驯化研究。主要研究了不同培养基配方对蛹虫草菌丝体生长情况的影响,结果表明在培养基配方1上菌丝生长较好。 相似文献
849.
AIM:To observe changes of serum asymmetry dimethylarginine (ADMA) and endothelin-1 (ET-1) levels,which reflect blood vessel endothelial function,after therapy of enhanced external counterpulsation(EECP) in patients who had taken percutaneous transluminal coronary angioplasty and stent.METHODS:Fifty one coronary heart disease patients (all of them had taken percutaneous tranluminal coronary angioplasty and stent) were distributed into two groups by matching them with ratio of 1∶2,17 patients in EECP group and 34 patients in control group.Both of two groups were given conventional medicine,in addition,EECP group was undertaken three courses of treatment of EECP.ADMA was detected by HPLC-fluorescence method,and ET-1 was detected by radio-immunity method.RESULTS:In EECP group ,compared with prior treatment,ADMA and ET-1 levels was obviously reduced (P<0.05).In control group,compared with prior treatment,ADMA had no significant difference (P>0.05) and ET-1 was higher (P<0.01).Compared between two groups,extent of decrease in ADMA and ET-1 levels in EECP group were more obvious than control group (P<0.01).Improvement of angina and decrease of frequency of angina was more obvious in EECP group than control group.Besides,decrease of ADMA level was positive correlation with them (r=0.85,0.70,respectively P<0.01).CONCLUSION:EECP reduces serum ADMA and ET-1 levels by increasing shear stress to vessel endothelium in coronary heart disease patients who had taken percutaneous tranluminal coronary angioplasty.It hints that EECP can improve endothelial function and provides experimental evidence for the combined treatment of coronary heart disease. 相似文献
850.