草必净防除马铃薯田杂草试验研究

试验结果表明,草必净防除马铃薯田杂草,在用药量170～260 mL/667 m2范围内,对马铃薯的生长发育没有影响,可有效地防除反枝苋、马齿苋、无芒稗、曼陀罗、藜等杂草。施药后30 d,总株防效为87.51%～97.11%;施药后45 d,总株防效为90.60%～98.26%,总鲜重防效为89.31%～97.74%。草必净在马铃薯田防除杂草最佳用药量为200 m/667 m2。     

安乡县稀直播稻田杂草发生规律及其化学防除效果

对安乡县水稻稀直播田杂草发生情况进行了调查,同时进行了化学防除试验,结果表明,水稻稀直播田由于用种量小（一季稻1～1.25 kg/667 m2,早稻2～3 kg/667 m2）、播种密度小,因而杂草种类多、密度高、发生早、出草期长,并具有两个出草高峰.用50%二氯喹啉酸WP 35～40 g/667 m2＋10%苄磺隆WP 9～12 g/667 m2、10%千金EC 40～60 ml/667 m2和56%二甲四氯DP 50 g/667 m2对稀直播稻田杂草进行＂二杀一补＂式的防治,除草效果好,安全性高.     

The long-term approach to parasitic weeds control: manipulation of specific developmental mechanisms of the parasite

Parasitic weeds pose a tremendous threat to world agriculture, mainly because they are at present almost uncontrollable. The root parasites Striga (witchweed) and Orobanche (broomrape) are vicious pests in both tropical and sub-tropical areas. A thorough understanding of their biology, including detailed knowledge of the specific mechanisms of parasitism, is needed in order to develop novel control methods. Some main developmental steps are described for the root parasites: seed conditioning and germination, haustorium formation, penetration into host tissues, maturation of the haustorium, and seed production. All these stages can be targeted in order to achieve parasite control. For example, based on our findings regarding gibberellin synthesized during seed conditioning, we were able to prevent parasitism by soil application of an inhibitor of gibberellin synthesis. Other developmental stages, such as germination stimulation, the enzymatic penetration of the haustorium into host tissues, and the source–sink relations between host and parasite are also possible targets for control, and the mechanisms involved may be manipulated for specific control of the parasites.     

水稻直播田抗药性杂草防控技术探讨

田间试验表明,采用“一封一杀”的动态防治模式,以“封闭为主,茎叶喷雾为辅”的防治策略较为符合浙中稻区水稻直播田生产用药实际。“一封一杀”是指播后芽前每667 m2用30%丙草胺EC100 mL进行土壤封闭,苗后杂草用300 g/L丙草胺EC100 mL+3%氯氟吡啶酯OD 53.3 mL、13%氰氟·氯氟吡啶酯EC 80 mL+100 g/L氰氟草酯EC100 mL、10%双环·双唑GG 200 g、39%敌稗·异噁草松EC 200 mL+85%丁草胺EC 47 m L喷施茎叶;或每667 m2用4%双唑草腈SC 150 mL进行土壤封闭、播后10～15 d上水撒施2%双唑草腈GR 600 g。     

稻田杂草中提取的天然抗氧化剂作用研究

采用分光光度法,测定了12种稻田杂草植株的乙醇提取液的吸光度(OD) 值。结果表明,稗、千金子、碎米莎草和鸭舌草8 h提取液的吸光度分别为0.0165、0.0215、0.0235和0.0120,均显著低于抗氧化剂茶多酚的,而与香薷的相当,表明这4种杂草乙醇提取物的抗氧化作用显著。在液料比12∶1、提取时间8 h、提取温度80℃,以0.3%抗氧化剂水溶液为溶剂,加工获得的鸭舌草乙醇提取液的抗氧化作用最强。     

利用扇形喷头进行棉花行间除草试验

利用扇形喷头于棉花生育中期进行行间除草具有精确效果,对棉花不产生药害。且雾滴细,附着度高,喷雾质量好,药液不易流失入土从而环保,防效和工效均比常规切向离心式喷头高,且除草安全。     

病虫草危害对稻米品质的影响

大力发展优质稻米产业已成为农业科研和生产的热点。影响稻米品质的因素除了品种因素、环境因素、栽培措施等外,病虫草危害也是一个重要方面。概述了病虫草危害对稻米外观品质、碾磨品质、食味品质、营养品质和卫生品质的影响。建议采用以“种苗处理+生态调控+应急防控”为核心的病虫草害绿色防控技术,能有效控制病虫草危害、保障粮食产量安全、提高稻米品质。     

Effects of long‐term grazing management on dandelion (Taraxacum officinale) in Agrostis capillaris grassland

Dandelion (Taraxacum officinale agg.) is a common forb species in grasslands in Europe. Although sometimes regarded as a valuable forage herb, it may become a weed, especially in arable land. There is limited information on the response of Taraxacum to long‐term grassland management practices. Therefore, we analysed cover and dry‐matter standing biomass of Taraxacum in a long‐term (1998–2012) grazing experiment on an Agrostis capillaris grassland. The following treatments were laid out on formerly abandoned grassland: (i) intensive grazing (IG); (ii) extensive grazing (EG); (iii) first cut followed by intensive grazing (ICG); (iv) first cut followed by extensive grazing (ECG); and (v) unmanaged grassland (U). During the first 10 years, all defoliation treatments (i–iv) supported the presence of Taraxacum, and the lowest proportion was recorded in the unmanaged treatment (U). During the final 7 years of the study, combined cutting and grazing promoted Taraxacum cover more than that of grazing only (ICG > IG > ECG > EG). Cover of Taraxacum was negatively affected by increasing sward height where Taraxacum plants had lower fitness. Due to the relatively strong relationship between percentage cover of Taraxacum and its dry‐matter biomass, percentage cover could be used as a simple method for the assessment of biomass of Taraxacum in a sward. Results are discussed in the context of adapting the management of A. capillaris grassland as a simple method for control of Taraxacum abundance, particularly in situations of extensification or abandonment.     

茶园12种攀援性杂草的发生和防治

通过多年调查湖南茶区茶园攀援性杂草(指以攀援为主的植物,有时也缠绕为害),并在湘东、湘北重点茶区定点系统观察;阐述了8科12种攀援性杂草的形态、特征、生物学特性、为害情况及无公害防治措施。     

长沙地区茶园杂草调查及防除关键措施

长沙地区各类茶园,春末、夏初的主要杂草是马唐、狗尾草、野塘蒿、扛板归、野艾蒿、狗牙根、革命草.为害程度:幼龄茶园>台刈茶园>成龄茶园.多年牛杂草占50%以上,提出防除多年生杂草滋生蔓延的关键措施.