8种杀虫剂防治棉花棉铃虫田间药效

近年来,江苏省丰县棉花棉铃虫发生有逐年加重趋势。为更好地指导棉农科学防治棉铃虫,保障本县棉花高产优质生产,笔者实施了30％茚虫威WG等8种药剂防治棉铃虫田间药效试验,筛选出一批新型高效低毒低残留农药。结果表明：30％茚虫威WG、150g·L^-1茚虫威SC、375g·L^-1硫双威SC、55％毒·氯EC、125g·L^-1高效氟氯氰菊酯SC用于防治棉花棉铃虫均有较好的速效性和持效性,均优于对照药剂480g·L^-1毒死蜱EC,且对棉花安全,适宜大面积推广应用。     

Effect of follistatin on pre‐implantational development of pig parthenogenetic embryos

The present study was designed to explore effects of follistatin (FST) on pre‐implantational development of parthenogenetically activated embryos (PAEs) in pigs. First, we investigated the FST messenger RNA expression level and dynamic FST protein expression patterns in porcine oocytes and PAEs. Then, PAEs were placed in embryo culture medium supplemented with 10 ng/mL of FST‐288, FST‐300, and FST‐315. Next, PAEs were cultured with 0, 1, 10 and 100 ng/mL of FST‐315 protein throughout the in vitro culture (IVC) duration. Further, 10 ng/mL of FST‐300 was added from the start of IVC in which PAEs were treated for 30, 48 and 60 h. The results showed that 1 ng/mL FST‐315 could significantly increase the total cell numbers of blastocyst and trophectoderm cell number in PAEs. Exogenous FST‐300 supplementation could significantly promote the early cleavage divisions and improve the blastocyst formation rate of porcine embryos. FST‐300 appeared to affect early embryonic development before activation of the embryonic genome. In all, the study confirmed for the first time that FST plays a role in promoting early embryonic development in pigs, which differed with different FST subtypes. FST‐300 could facilitate the initial cleavage time and improve the blastocyst formation rate, and FST‐315 could improve the blastocyst quality.     

河北省新农村建设评价指标体系构建研究

首先构建了河北省新农村建设的评价指标体系,并用该评价指标体系对河北省五个行政村的新农村建设情况进行了评价,评价结果表明五个行政村村容整洁与管理民主状况比较好,而生产发展、生活宽裕、乡风文明三个方面实现程度较低.     

红枣干燥技术与装备研究进展

为了探索开发适宜缩短红枣干燥时间、提高红枣干燥品质的技术与装备,综述了红枣单一与联合干燥发展现状与研究进展,并在此基础上进行了红枣干燥技术与装备的对比分析.同时,阐述了预处理对红枣干燥特性的影响,以期为在研究红枣干燥特性和干燥装备现状的基础上,对不同红枣干制品实施适宜的干燥加工技术与研制新型干燥装备提供理论依据与技术支...     

昆明鼠卵母细胞的孤雌发育及对其干扰核移植试验的预防措施

本文着重研究了在昆明鼠细胞核移植过程中，卵母细胞孤雌发育的激活原因、形成过程，并提出了一些防止其干扰细胞核移植的措施。     

中部地区城市体系的规模等级结构研究与检验

中部地区是我国重要的制造业、农产品、能源资源三大主要基地,也是城市分布较为密集的地区。与我国的其他地区相比,这一地区已形成了一个相对较为完善的现代城市体系。规模等级结构分析是从城市的规模和城市规模位序的关系来考察一个地区城市体系规模分布的重要手段。采用这一方法对中部城市体系进行分析。用帕累托分布对分析结果进行检验。从中发现中部城市体系存在的问题,并对该地区的城市发展提出建议。     

微肥与杀菌剂配施对玉米茎基腐病的防治及增产效果

研究了ZnSO_4·7H_2O、MnSO_4与五氯硝基苯可湿性粉剂和福美双可湿性粉剂配施防治玉米茎基腐病的效果及对玉米生长发育的影响。结果表明,微肥与杀菌剂配施,有利于促进玉米根系发育,培育壮苗,增强抗病能力,提高对玉米茎基腐病的防效。玉米拌种用量ZnSO_4·7H_2O6g/kg MnSO_46g/kg 50％福美双3g/kg 40％五氯硝基苯3g/kg,对玉米茎基腐病的防效88.75％～92.17％,较微肥处理和杀菌剂处理分别增产4.77％～6.42％和6.25％～11.80％。     

低磷胁迫对草莓幼苗根系生长和酸性磷酸酶活性的影响

为探讨低磷胁迫对不同品种草莓幼苗的根系生长和酸性磷酸酶活性(APA)的影响,试验选取4个草莓品种（‘红颜’、‘章姬’、‘甜查理’、‘童子一号’）,采用水培的方法,设正常磷处理(KH2PO4 1×10-3 mol/L)、低磷处理(KH2PO4 1×10-6 mol/L)2个处理,分别于处理后0、7、14、21、28、35 天,取样对其根系分泌酸性磷酸酶活性进行测定分析,并于处理后35天,测定其根鲜重、主根长、侧根数。结果表明,草莓幼苗受低磷胁迫后,其主根长度受到了抑制,而同期测定的侧根数、根鲜重、根冠比则显著增加。根系分泌的酸性磷酸酶活性在低磷处理早期就有显著提高,且随着低磷胁迫的延续,其活性持续升高;各项形态、生理指标显示,供试4种草莓品种中,‘甜查理’相对于其他供试草莓品种对低磷胁迫环境适应性较好,说明可以通过选择、改良草莓的根系特性来提高草莓的磷效率。     

苏锡常地区城市公园土壤微量元素分布特征及其环境指示意义

在江苏省国土1/250 000多目标地球化学调查基础上,选择苏州市、吴江市、无锡市、江阴市、常州市、金坛市等45个城市公园土壤作为研究对象,系统研究了当地典型城市公园土壤中Cd、Hg、Pb、Zn、Sb、Sn、B、Se、N、稀土元素(REE)等50个元素含量及土壤pH、总有机碳(TOC)等分布特征。结果表明,城市公园土壤的微量元素分布与城区污染土壤、农田土壤有显著差异,公园土壤的重金属含量总体偏低、N与TOC含量明显低于农田土壤,在公园土壤中S、Se、Cd、Pb、Zn、TOC等元素未出现高强度的人为富集,重金属污染以轻度Hg污染为主,S、Se、Cd、Pb、TOC、pH等指标在200 cm深度内分布相对稳定、未出现元素含量在不同深度的显著变化,指示多数公园土壤的微量元素分布总体上较一般城市土壤更少受人为因素干扰,可为人为活动对城市土壤环境的影响研究提供重要的参比对象。     

Actions of quinolizidine alkaloids on Periplaneta americana nicotinic acetylcholine receptors

BACKGROUND: Botanical insecticides do not play a major role as crop protectants, but they are beneficial in some applications. The authors investigated the actions of naturally occurring alkaloids on insect nicotinic acetylcholine (ACh) receptors (nAChRs) by evaluating their abilities to inhibit specific binding of [³H]imidacloprid (IMI) to nerve‐cord membranes from Periplaneta americana L. Two alkaloids were also tested for their actions on nAChRs expressed by cockroach neurons using patch‐clamp electrophysiology. RESULTS: Four natural quinolizidine alkaloids (matrine, sophocarpine, cytisine and aloperine) exhibited more than 50% inhibition of [³H]IMI binding at 10 µM , although other compounds were found to have no or low inhibitory activity. The rank order of potency based on concentration–inhibition curves was cytisine > sophocarpine ≥ aloperine ≥ matrine. Patch‐clamp analysis indicated that sophocarpine and aloperine were not agonists of nAChRs expressed in P. americana neurons, yet, at 10 µM , aloperine, but not sophocarpine, suppressed ACh‐induced inward currents significantly. CONCLUSION: Three of the four natural alkaloids tested possess structural moieties that are necessary for interaction with P. americana nAChRs. Aloperine, which possesses a unique structure and showed a distinctive dose–response curve, was found to act as an antagonist. Appropriate modifications of these alkaloids might result in novel insecticidal nAChR ligands. Copyright © 2008 Society of Chemical Industry