甘薯茎线虫病防治技术初探

将带有甘薯茎线虫病的病薯完全粉碎后接种土壤,薯苗栽植时一部分处理用辛硫磷500倍、800倍浸根,一部分处理采用生物制剂阿维菌素3 000倍、5 000倍液浇窝,不施药用清水浇窝作为对照,进行甘薯茎线虫病防治试验。结果表明：辛硫磷800倍浸根处理能有效的防治甘薯茎线虫病,薯块发病指数低于其他处理,防治效果高于其它处理。阿维菌素3 000倍处理作为高效低毒的生物制剂农药也可以应用到甘薯茎线虫病的防治上。     

红麻病虫防治试验初报

本试验采用农业防治和化学防治两种方法防治红麻病虫害，试验结果表明，托福灵是一种高效低毒杀菌剂，对红麻立枯病和炭疽病有较好防治效果。辛硫磷是一种长效高效杀虫剂，对红麻地下害虫和根结线虫病有较好防治效果。轮作也是防治根结线虫病的有效办法。Bt乳剂对红麻造桥虫有很好的防治效果。     

云南木薯蛴螬的药剂防治技术研究

为有效控制木薯园蛴螬的危害,筛选其药剂防治技术。采用"Z"字型取样法对云南木薯园蛴螬种类进行调查,结果表明:危害当地木薯的主要地下害虫种类为痣鳞鳃金龟。选取3种药剂不同配比及浓度,采用土壤药剂处理方法进行田间药效试验,试验结果表明:"40%辛硫磷乳油2 520 m L/hm2与1.8%阿维菌素乳油1 680 m L/hm2混合液"对蛴螬有较好的防效,显著降低了植株死亡率、虫薯率和虫害率,增产幅度较大,可作为木薯蛴螬药剂防治技术推广应用。     

不同药剂拌种对花生地下害虫的防治试验

采用药剂拌种,筛选防治花生地下害虫的药剂。结果表明,在花生果实膨大期,三种药剂各处理对花生田地下害虫的防治效果达60％以上,20％氯虫苯甲酰胺SC450g/hm2、22％吡虫·辛硫磷EC6750g／hm2。的防治效果达70％以上,但各处理差异不显著;花生果实收获期,20％氯虫苯甲酰胺SC450g/hm2、22％吡虫·辛硫磷EC6750g/hm2、地鹰20kg种子／100g的防治效果达60％以上。表明20％氯虫苯甲酰胺SC、22％毗虫·辛硫磷EC、地鹰在花生播种时拌种可用来防治地下害虫。     

浙西北茶区茶尺蠖对联苯菊酯等药剂抗药性初步测定

茶尺蠖是浙江茶叶主产区的主要害虫之一,其抗药性问题日益突出,严重影响茶叶生产,测定浙江茶叶主产区茶尺蠖对常用药剂的抗药性对其合理防治具有重要意义。测定了浙江省萧山区、西湖区、富阳区、余杭区和安吉县等茶叶主产区茶尺蠖对联苯菊酯、溴氰菊酯、功夫菊酯和辛硫磷四种常用药剂的抗药性。结果显示:浙江省主要产茶区茶尺蠖种群对以上四种常用药剂均产生了一定程度的抗性,且对辛硫磷产生的抗性水平最高,其次是联苯菊酯,几个主要产茶区中以余杭区茶尺蠖的抗性水平最高,这与其茶园管理模式有密切关系。浙江省各茶叶产区需要根据本地茶园管理模式合理选择药剂防治茶尺蠖。     

庄浪县马铃薯地下害虫危害规律及药剂防治研究

为防治马铃薯地下害虫,选取有代表性的马铃薯田块,分别在春季播种前和秋季成熟期调查地下害虫种类及发生危害情况,并研究4种药剂不同剂量对马铃薯地下害虫的防治效果。马铃薯地下害虫春季平均虫口密度3.3头/m2,最高6.9头/m2;秋季平均虫口密度2.9头/m2,最高7.5头/m2,发生程度为中度。用虫情指数和被害块茎率评价防治效果,用增产率衡量保产效果,15%毒死蜱·辛硫磷GR 45 000 g/hm2、15%阿维毒死蜱GR 37 500 g/hm2和3%克百·敌百虫GR 30 000 g/hm2,对马铃薯田地下害虫防治效果较好,防效在50%以上,增产范围9.1%~10.1%。     

6种药剂对大豆田蛴螬的田间药效试验

通过田间小区试验比较了70%噻虫嗪种子处理水分散粒剂WDG(锐胜)、60%吡虫啉悬浮种衣剂FS(高巧)、3%辛硫磷颗粒剂GR、40%毒死蜱辛硫磷乳油EC、15%阿维毒死蜱乳油EC、15%阿维辛硫磷乳油EC 6种杀虫剂对大豆田蛴螬的防治效果及大豆增产的效果。结果表明,药剂处理后,对大豆安全,未出现药害;70%噻虫嗪WDG对蛴螬的防效达79.41%,大豆增产率为45.43%;60%吡虫啉FS对蛴螬的防效为76.47%,大豆增产率为48.03%;70%噻虫嗪WDG和60%吡虫啉FS的试验效果显著高于防效和增产率分别在54.41%~69.12%、22.09%~34.56%之间的其他4种药剂;6种药剂对大豆苗期和成熟期大豆植株的株高、鲜重、单株豆荚数等指标均未产生显著影响。     

速灭杀丁与辛硫磷混用防治荔枝蝽蟓的增效作用

试验证明,速灭杀丁与辛硫磷混用,对半翅目荔枝蝽蟓的防治有较好的增效作用,其中以速灭杀丁:辛硫磷=1:9混配,可增效10倍以上。这对降低防治成本,扩大防治范围,延缓害虫抗药性的产生具有重要意义。     

茶核·苏云金防治茶尺蠖的田间药效试验

茶尺蠖（Ectropis oblique Wehrli）又名拱拱虫，是茶树的主要食叶类害虫之一，以取食茶树嫩叶为主，发生严重时可将成片茶园食尽，严重影响茶树的树势和茶叶的产量。几十年来，主要靠化学农药防治，出现世代重叠现象用辛硫磷防治效果较好，但用的次数多了，产生抗药性，对防治茶尺蠖带来了难度。本课题使用茶核·苏云金进行试验，以茶尺蠖出现世代重叠现象时的常用药剂辛硫磷作为参比，现将结果报告如下：     

种衣剂对花生的保苗效果试验初报

花生播种后常遭受金针虫、蝼蛄、蛴螬等地下害虫侵袭,出苗后蚜虫又为害幼苗,有时传染病害,造成花生缺苗,有时甚至补种几次仍不能全苗,给生产带来严重影响。为防病虫保全苗,1990年作了种衣剂对花生的保苗效果试验,现简结如下。 材料与方法 1、供试药剂:国产种衣剂4号、美国产FMC种衣剂、日本产大扶农种衣剂(均由中国农科院提供,胶体),辛硫磷(市售)。     

Comparative soil distribution and dissipation of phoxim and thiamethoxam and their efficacy in controlling Bradysia odoriphaga Yang and Zhang in Chinese chive ecosystems

Bradysia odoriphaga Yang and Zhang (the chive gnat) is the major insect pest affecting Chinese chives (Allium tuberosum Rottl. ex Spreng.) in Northern China. Only three insecticide products are registered for its control. In the present study, we compared the persistence and distribution of thiamethoxam and phoxim in soil and determined their long-acting control effects against B. odoriphaga and two other secondary pests, Thrips alliorum Priesner and the Asiatic onion leaf miner Acrolepia alliella Semenov and Kuznetsov (Lepidoptera: Acrolepiidae), after a single soil application using the directional spray-washing method during the early Chinese chive root-rearing period. Under the same applied dosage, the rhizosphere soil at a depth of 4.0–10.0 cm had concentrations of thiamethoxam and phoxim ranging from 2.21 to 7.44 mg/kg and 0.09–0.44 mg/kg, respectively, at the 7th day after application. The half-lives of thiamethoxam and phoxim in the soil were 27.5 and 6.7 days, respectively. Thiamethoxam persisted for 210 days, whereas phoxim only persisted for 45 days in the soil and plants. In addition, thiamethoxam applied at 6.0 kg a.i./ha maintained a low population density of B. odoriphaga, T. alliorum and A. alliella for nine months longer than phoxim. In conclusion, thiamethoxam may help farmers more effectively manage B. odoriphaga and other secondary pests on Chinese chive and reduce the costs of insecticide use while sustaining protection.     

Evaluation of Sensitivity to Phoxim and Cypermethrin in an Endoparasitoid,Meteorus pulchricornis (Wesmael) (Hymenoptera: Braconidae), and Its Parasitization Efficiency Under Insecticide Stress

Insecticides can have consequences for beneficial arthropods. Insect parasitoids can contact insecticides through direct exposure spray droplets or residues on crop foliage. Here, we focus on better understand the response of Meteorus pulchricornis (Wesmael), a parasitoid wasp of lepidopteran pests, and its detoxification mechanisms on stress caused by phoxim and cypermethrin. Hence, we determined the dose–mortality curves and estimating the sublethal concentrations (LC₃₀ and LC₅₀). Then, we applied the sublethal concentrations against adult parasitoids to assess its survival, parasitism efficacy, and also developmental and morphometric parameters of their offspring. Simultaneously, we check the activities of glutathione S-transferase (GST), acetylcholinesterase (AChE), and peroxidase (POD) after sublethal exposure of both insecticides, which has measured until 48 h after treatment. Overall, phoxim and cypermethrin exhibited acute lethal activity toward the parasitoid with LC₅₀ values 4.608 and 8.570 mg/liter, respectively. Also, we detect that LC₃₀ was able to trigger the enzymatic activity of GST, AChE, and POD, suggesting a potential detoxification mechanism. However, even when subjected to sublethal exposure, our results indicate strong negatives effects, in particular for phoxim, which has affected the parasitism efficacy and also the developmental and morphometric parameters of M. pulchricornis offspring. Therefore, it can be concluded that both phoxim and cypermethrin have negative impacts on M. pulchricornis and we suggest cautioning their use and the need for semifield and field assessments to confirm such an impact.     

几种新农药防治甘蔗害虫效果

试验结果表明,3.6%加强型杀虫双GR、3.6%普通型杀虫双GR和8%杀螟丹.辛硫磷GR 3种农药对甘蔗螟虫均有较好的防治效果,其中对螟害枯心率防效均达80%左右,对螟害株率防效均达69%以上;5%辛硫磷GR、3.6%加强型杀虫双GR和5%新型甲拌磷GR 3种农药对金龟子田间残留虫口数防效最佳,防效均达80%以上。它们可作为防治甘蔗螟虫、金龟子的替换农药,田间使用剂量以60～90kg/hm2为宜。     

6个紫肉甘薯新品系比较试验初报

以金山57和Ayamurasiky为对照,通过比较试验,初步分析了福建省泉州农业科学研究所新近选育的6个紫肉甘薯品种(系)的鲜薯产量、薯块烘干率、食味品质和花青素含量等主要经济性状,并评述了其在生产或育种上的利用价值。这些品系的育成,丰富了紫肉甘薯育种材料;同时提出以紫肉甘薯品种或中间材料为亲本,进行计划集团杂交或放任授粉,扩大基因背景和杂种后代的选择群体,是选育紫肉甘薯品种的有效途径之一。     

特用甘薯的研究进展及综合开发利用

根据近年来我国特用甘薯的研究状况以及实际生产的需要,扼要地阐述了目前我国各类特用甘薯的育种进展、育种成果、综合利用及发展前景,为特用甘薯的深入研究和开发利用提供参考。     

甘薯高淀粉育种途径的探讨

对甘薯高淀粉育种的紧迫性、相关性及技术方面进行了综合剖析,旨在促进甘薯高淀粉育种的研究,为高淀粉甘薯新品种的选育提供参考依据。     

甘薯育种亲本及组合评价

对南充市农业科学研究所“十五”期间主要选用的甘薯亲本材料作母本、父本组合的实生苗及其后代表现进行分析,其结果,84-2315、9014-3、AB940078-1、绵粉一号、徐薯18、浙13、三合薯、台农10号是较好的高淀粉育种亲本材料。高淀粉育种应该利用这些亲本多配组合或进行集团杂交,以期从其后代中筛选高淀粉甘薯新品种。84-2315、9014-3、潮薯一号、绵粉一号、徐薯18、南薯99、农林10号、坦桑尼亚是较好的高产饲用型育种亲本材料,高产饲料型品种选育应利用这些亲本材料多配组合或进行集团杂交,以期从其后代中筛选高产饲料型甘薯新品种。     

Root System Development of Cassava and Sweetpotato during Early Growth Stage as Affected by High Root Zone Temperature

Abstract

Root zone temperature (RZT) is an important factor that affects the establishment of crops in the field. This study was conducted to determine the effect of high RZT on the root system development of cassava and sweetpotato and to assess the response of each root system component of cassava and sweetpotato to high RZTs. Cassava and sweetpotato are widely grown crops in soils that are prone to reach a high temperature especially during the dry season. The plant root system was the primary object of investigation in this study. Cassava and sweetpotato cuttings were grown in pots for 20 days in a growth chamber where two different soil temperature regimes were maintained : 40°C (high RZT) and 25°C (normal). High RZT significantly decreased the total length of the adventitious roots (ARs) and the number and total length of the first order lateral roots (LRs) in both cassava and sweetpotato. Reduction in these root growth parameters was greater in the latter than in the former. High RZT caused a marked increase in the number of the second order LRs in sweetpotato and tended to enhance the formation of the third order LRs. Under high RZT, in cassava, a higher proportion of the total number of ARs and the first order LRs, and thus, a greater fraction of the total root length came from the lower nodes of the cuttings that were buried deep in the soil at planting. In sweetpotato, a greater proportion of the total number and total length of the ARs and the first order LRs was observed in the nodes of the cuttings that were buried closer to the soil surface than those buried deeper. An opposite trend was evident in both cassava and sweetpotato grown under a normal RZT. In the screenhouse experiment where plants were grown for 12 days, root growth of cassava was significantly reduced by the high RZT that prevailed when the soil was not covered with mulch materials. The root development in the mulched soil was similar to that under normal RZT in the growth chamber.