加压滴灌技术在棉花、小麦上应用的经济效益评价

采用经济学评价方法,通过对加压滴灌棉花和小麦生产和管理运行成本、单位面积产值、纯收益和成本收益率等进行全面的分析评价,并与常规地面灌棉花和小麦进行对比分析,为加压滴灌在粮食作物上的进一步扩大推广提供依据.结果表明.加压滴灌棉花纯效益每公顷为10859.1元,成本纯收益率为64.82%,与常规灌溉棉花生产相比,成本纯收益...     

杂交稻稻瘟菌致病菌系的组成及其变化

对四川省大面积主栽杂交稻组合汕优６３、汕优２号上的稻瘟病菌进行生理小种测定的结果表明，致病菌系由多个生理小种群组成，其中以ＺＢ、ＺＣ群小种为主。用不同生理小种的菌株接种汕优２号和汕优６３的结果表明：ＺＢ群小种对汕优２号的致病频率最高，为１００％，而不同生理小种群对汕优６３的致病频率无显著差异，平均为７５％。致使这两个杂交稻组合丧失抗性的菌株来自四川省发病多年的常规稻、雄性不育系和早熟杂交稻组合。四     

喷雾干燥鱼浆蛋白粉营养成分分析

本试验对鱼粉加工废水鱼浆蛋白粉(经浓缩、水解、喷雾干燥得到的副产品)进行营养成分分析,其中粗蛋白质含量达64.08%,钙2.67%、磷1.12%,钙磷比例合理;各氨基酸含量分别为:赖氨酸3.29%,蛋氨酸0.94%,谷氨酸5.17%,牛磺酸2.50%。     

修剪频率对混播草坪土壤呼吸特征的影响

以草地早熟禾(Poa pretensis)和高羊茅(Festuca arundinacea)混播草坪为研究对象,采用开路式土壤碳通量测量系统Li-8100对不同修剪频率下草坪的土壤呼吸昼夜变化特征进行研究,旨在探讨修剪对城市草坪土壤呼吸特征的影响。结果表明:草坪在1周修剪1次、2周修剪1次和常规修剪(对照)这3种情况下,其土壤呼吸速率昼夜变化均呈单峰曲线模式,且3种情况下草坪土壤呼吸速率日最高值均出现在12:00-14:00,而日最低值出现的时间不一;从草坪土壤日呼吸总量来看,6月与7月草坪在1周修剪1次处理、2周修剪1次处理和对照之间差异均不显著,8月草坪在1周修剪1次处理下与对照之间差异不显著,而两者与草坪2周修剪1次的处理之间差异显著(P<0.05);从整体来看,3种情况下草坪的土壤呼吸速率均与5 cm土层地温成显著正相关(P<0.05),与其他温度指标的相关性因不同月份和不同处理而不同,而草坪土壤呼吸的Q₁₀值的大小基本上都随着土层深度增加而增加。     

水飞蓟田间除草剂筛选试验

为了明确几种除草剂对水飞蓟的安全性及对水飞蓟田杂草的防除效果,通过田间小区试验对水飞蓟田播后苗前除草剂进行筛选。结果表明:精异丙甲草胺96%悬浮剂720～1 008g(a.i.)/hm2、仲丁灵48%悬浮剂720～1 440g(a.i.)/hm2和二甲戊乐灵33%悬浮剂495～990g(a.i.)/hm2对水飞蓟安全且除草效果良好。     

楝科植物杀虫作用研究进展

楝科植物中含有大量的活性成分,在药用、杀虫等方面具有独特的效果,是目前研究比较深入的植物种类之一.     

Screening of cotton germplasm for resistance to Verticillium dahlia Kleb. under greenhouse and field conditions

Currently, the most effective and economically feasible means of controlling Verticillium wilt is to grow wilt-resistant cultivars. Nevertheless, resistant germplasm lines that are able to overcome this detrimental disease remain rare. Hence, we aimed to identify high-quality germplasm lines that exhibit high resistance, to address the dearth in optimum production. Our field and greenhouse studies showed significant variation among all tested germplasm lines with respect to wilt-assessment parameters. Highly resistant or resistant germplasm included 1421Bt-4133, O Siv2, Arcot-1, and GP93; Zhong 21371 and Yumian 2067 were moderately responsive; and Arcot402bne, Arcot438, Xinluzao-3, and Jimian11 were highly susceptible to wilt. Overall, germplasm line 1421Bt-4133 appeared to be an ideal material with strong resistance potential against V. dahliae. The germplasm lines O Siv2, Arcot-1, GP93, Zhong 21371, and Yumian 2067 showed variability in resistance potential in artificially or naturally-infested soil. This variability may be due to the genetic potential of the plants and to the adaptability of V. dahliae. We determined that the 1421Bt-4133 germplasm line was ideal, as it demonstrated resistance diversity against V. dahliae in all observed wilt-assessment parameters. The results of this study contribute to the understanding of viable germplasm lines for improving cotton production. The resistant germplasm lines uncovered in this study may provide new disease resistance sources in the breeding program.     

水葫芦病原菌的研究进展

水葫芦是世界上危害最严重的水生杂草之一。目前,运用病原菌来治理水葫芦日益受到关注。本文介绍了水葫芦致病真菌、细菌和它们的有关代谢产物——植物毒素的研究进展,并探讨了利用病原菌防除水葫芦的前景。     

The discovery of HNPC‐A3066: a novel strobilurin acaricide

BACKGROUND: Although more than ten strobilurin analogues have been commercialized since 1996 as fungicides, only one was available as an acaricide as of 2003. To search for novel strobilurin analogues with unique biological activities, a synthetic screening programme was carried out. RESULTS: Syntheses of compounds analogous to the commercialized fungicide metominostrobin and the acaricide fluacrypyrim led to the discovery of a lead compound, (E)‐2‐{2‐[[3,5‐bis(trifluoromethyl)phenoxy]methyl]phenyl}‐2‐(methoxyimino)‐N‐methylacetamide (3b), that showed moderate acaricidal activity against Tetranychus urticae Koch. Compound 3b has a 3,5‐(CF₃)₂‐phenoxymethyl group instead of the unsubstituted phenoxy substituent in metominostrobin. Optimization of compound 3b was achieved by introducing an oxime ether bridge along with an alkylthio(alkyl) branch in place of the oxymethylene chain between two aromatic moieties, as well as by replacing the methoxyiminoacetamide group with a methoxyacrylate structure, leading to (E)‐ methyl 2‐{2‐[[[(Z)[1‐(3,5‐bis(trifluoromethyl)phenyl)‐2‐methylthioethylidene]amino]oxy] methyl]phenyl}‐3‐methoxyacrylate (6c) and (E)‐ methyl 2‐{2‐[[[(Z)[1‐(3,5‐bis(trifluoromethyl)phenyl)‐1‐methylthiomethylidene]amino]oxy]methyl]phenyl}‐3‐methoxyacrylate (9a, HNPC‐A3066). CONCLUSION: The above two compounds (6c, 9a) were shown to exhibit potent acaricidal and fungicidal activity. Compound 9a (HNPC‐A3066) also exhibits larvicidal and ovicidal activities against various acarids. The acaricidal potency is comparable with those of commercial acaricides such as fluacrypyrim, tebufenpyrad and chlorfenapyr. Copyright © 2008 Society of Chemical Industry     

农业景观与害虫种群控制

20世纪以来,我国农村城镇化和农业设施化的快速发展,造成农业景观的急剧变化以及农田生境的破碎化。国内外十分重视这种景观变化对农业生态系统功能和生物多样性以及害虫种群控制的影响。本文针对国内外有关农业景观变化和生境破碎化对昆虫与天敌群落组成、多样性及种群序列变化的影响研究进行系统论述,着重介绍农业景观变化对害虫种群控制的原理和作用机理,分析景观结构与农田生物多样性,及寄主—寄生物、猎物—捕食者、植物—害虫—天敌的相互关系,以及影响这种关系的景观因子作用力的模拟,旨在揭示农业景观变化对害虫种群动态的潜在影响,提示了今后害虫治理研究的热点问题。