转Bt基因抗虫棉对棉蚜的风险评价进展

本文从转Bt基因抗虫棉和Bt杀虫剂抗虫机理分析了转Bt基因棉对棉蚜的潜在风险.综述了转Bt基因棉对棉蚜生态风险评价的研究进展,分析了不同研究结果产生的原因.     

新疆棉区棉蚜控制策略探讨

阐述了应从新疆特殊的自然环境条件特点出发,以生态治理为根本策略,科学地治理棉蚜危害的观点。     

甜菜夜蛾幼虫对常规棉和转基因棉的取食选择行为

本文研究了甜菜夜蛾Spodoptera exigua幼虫在转基因棉和常规棉上的取食行为反应,以及有/无学习经历对其取食选择的影响及选择行为对蛹重的影响。结果表明,用人工饲料饲养至3龄5、龄的甜菜夜蛾幼虫在常规棉品种33和转基因棉品种33B上、常规棉品种石远321和转基因棉品种SGK321上的取食选择行为除24h内更多的5龄幼虫选择了石远321,在其它时段,幼虫并没有表现出对转基因叶片的规避行为,甚至有些时段更多地选择在转基因叶片上取食;分别用33叶片、33B叶片饲喂至3龄的甜菜夜蛾幼虫进行33和33B的取食选择,以及分别用石远321S、GK321的叶片饲喂至3龄的甜菜夜蛾幼虫进行石远321和SGK321的取食选择均未表现出对转基因棉的规避行为。上述所有处理中,甜菜夜蛾在常规棉上化蛹的蛹重与转基因棉上化蛹的蛹重无显著差异。结果表明,甜菜夜蛾对单价转基因棉33B和双价转基因棉SGK321均未表现出行为抗性。因此,在转基因棉花的害虫治理中要特别关注甜菜夜蛾的防治。     

Integrated Control in Peruvian Cotton

From field trials with artificial infestation of rice yellow stemborer Scirpophaga incertulas (Walker) (YSB) egg masses over the post-transplanted crop cycle and reports in the literature, it was concluded that rice passes through three stages of general morphological resistance interceded by two stages of susceptibility. Resistance occurs on very young rice, at mid-growth, and after panicle exsertion. The resistant period at mid-growth varied by plant maturity. On an early maturing rice variety (IR72), resistance occurred from panicle initiation (PI) to pre-booting, while on the medium maturing IR70, resistance was extended from the late vegetative stage to booting. High deadheart (severed tiller) densities occurred post transplanting because, being small, up to three tillers are damaged by a single larva. Whiteheads (severed panicles) were formed from infestations from booting onwards and were relatively higher than deadhearts on the early maturing variety but relatively less on the medium maturing variety. Zinc deficiency delayed maturity of IR72, and the period of naturally high resistance of seedlings was extended throughout most of the vegetative stage as well as after PI through pre-booting. Resistance at mid-growth and after panicle exsertion could be from: (1) lignin and cellulose deposits on the cell walls, (2) tight wrapping of the leaf sheath, and (3) deposition of silica. All three trials produced similar quadratic models of the yield response to crop age when infested. Deadheart damage was compensated to a large degree, but lowest yields occurred from whitehead damage when infested at or just after the pre-booting stage.     

棉田棉蚜种群动态及瓢虫对棉蚜种群数量的影响

根据新疆尉犁县4种棉花品种的棉田调查,利用棉蚜数量和时间进行回归分析,探讨其种群动态,应用棉蚜数量和瓢虫数量进行相关分析,研究棉田棉蚜种群与瓢虫种群的关系。结果表明,在不同品种的棉田中,棉蚜种群数量基本呈指数规律上升与下降。在尉犁县孔雀农场的中棉35和军棉1棉田中,从2001年5月31日至6月28日棉蚜种群数量呈指数增长,从6月28日至7月26日棉蚜种群数量呈指数下降。在尉犁县达西村的抗虫棉9和新陆中11棉田中,棉蚜种群数量开始发生和发生高峰期均比中棉35和军棉1推迟1周左右,其中抗虫棉9棉田的棉蚜发生高峰期数量最多,而新陆中11棉田的棉蚜发生期数量最少。在不同品种的棉田中,瓢虫是棉田棉蚜的主要天敌,对棉蚜起控制作用,它与棉蚜种群数量呈显著的跟随关系,发生期比棉蚜滞后1周左右。     

Management of Cotton Pests1

The interplay between plant carbohydrate balance and various kinds of insects damage is described for cotton growth and development in a general way.     

杀虫荧光假单胞工程菌对棉铃虫的离体及活体生物测定

利用转座子mini Tn5将δ 毒素基因cryIA(c)整合到生防细菌荧光假单胞菌P30 3 1的染色体上 ,构建成荧光假单胞工程菌。以棉铃虫二龄幼虫作供试昆虫的离体生测表明 :在同一剂量水平上 ,PT4 5、PT51、PT6 1、PT71等工程菌株对棉铃虫幼虫的杀虫活性均高于野生菌株HD 73;浓度最高时PT4 5、PT51、PT6 1、PT71、HD 73处理棉铃虫的死亡率分别为 86 7%、76 7%、80 0 %、86 7%、70 0 % ,死亡率与浓度呈正相关 ,体重与浓度呈负相关。用上述工程菌接种棉花活体 ,喷雾处理 3周后 ,用棉叶饲喂的棉铃虫死亡率分别达 70 0 %、6 0 0 %、6 0 0 %、6 6 7%、33 3% ;用棉顶尖饲喂的棉铃虫死亡率分别达 70 0 %、6 3 3%、6 0 0 %、73 3%、30 0 % ;用棉蕾饲喂的棉铃虫死亡率分别为 6 3 3%、53 3%、50 0 %、6 3 3%、2 6 7%。     

杀虫荧光假单胞工程菌对棉铃虫的离体及活性生物测定

利用转座子mini-Tn5将δ-毒素基因cryIA(c）整合到生防细菌荧光假单胞菌P303-1染色体上，构建成荧光假单胞工程菌，以棉铃虫二龄幼虫作供试昆虫的离体生测表明：在同一剂量水平上， PT45、PT51、PT61、PT71等工程菌株对棉铃虫幼虫的杀虫活性均高于野生菌株HD-73。浓度最高时PT45、PT51、PT61、PT71、HD-73处理棉铃虫的死亡率分别为86.7%、76.7%、80.0%、86.7%、70.0%，死亡率与浓度呈正相关，体重与浓度呈负相关，用上述工程菌接种棉花活体，喷雾处理3周后，用棉叶饲喂的棉铃虫死亡率分别达70.0%、60.0%、60.0%、66.7%、33.3%，用棉顶尖饲喂的棉铃虫死亡率分别达70.0%、63.3%、26.7%。73.3%、30.0%；用棉蕾饲喂的棉铃虫死亡率分别为63.3%、53.3%、50.0%、63.3%、26.7%。     

棉铃虫多代连续取食转基因抗虫棉的抗性演变

1997－1999年,用含45％Bt CPT1双抗基因棉半人工饲料饲喂棉铃虫幼虫5．5天,连续16代汰选。结果：幼虫校正死亡率由79．18％下降到49．36％;其体长达取食45％泗棉3号半人工饲料幼虫平均体长,由第一代的0上升到第16代的23．32％;幼虫体长、体重增长速率由第一代负增长分别上升为55．29％和366．67％。表明棉铃虫幼虫经取食转基因抗虫棉连续16代,其中肠对抗虫棉已产生一定的亲和性及适宜性,进入早期抗性阶段。     

磁化水滴灌对棉田土壤脱盐效果及棉花产量的影响

以棉花为对象进行磁化水滴灌试验,通过田间小区试验,设置一次磁化、二次磁化和CK处理,研究不同磁场强度处理水灌溉对棉田土壤脱盐效果以及对棉花生长状况和增产效果的影响,旨在提出一种改良土壤盐渍化的新技术。结果表明:滴灌条件下磁化水可以有效增强对土壤全盐含量、Cl~-和Na~+的淋洗作用,二次磁化和一次磁化处理的脱盐作用显著大于对照处理,且二次磁化中3 600~2 000 m T效果最佳,二次磁化和一次磁化处理全盐含量分别降低了25.5%和19.5%,CK降低了10.46%;磁化水灌溉可以提高棉花的生物量,缓解盐分对棉花的伤害,提高棉花产量,增产率达9.61%~15.32%。     

Bacterial Blight of Cotton in Sudan

Abstract

This paper is in effect a summary of three COPR reports (Pope, 1973 and 1974, Pope and Watt, 1975) which is intended to give the reader an indication of possible uses for light hovercraft under field conditions both in the United Kingdom and overseas. Some suggestions are made as to possible uses and various forms of equipment and modifications are described and discussed.     

北方特早熟棉区棉铃虫抗药性发展动态监测

棉铃虫是北方特早熟棉区主要害虫之一，其发生频率高，用药次数多，使其对杀虫剂易产生抗性，致使防治困难，对棉花生产构成威胁。为摸清棉铃虫的抗性发展规律，我们于１９９７～２０００年选择主产棉区朝阳作为抗性监测点，监测棉铃虫对拟除虫菊酯类氯氰菊酯、有机磷类久效磷和氨基甲酸酯类灭多威农药的抗性发展情况，以期累积资料，了解棉铃虫抗性发展的规律，探索抗性治理对策，延长药剂使用寿命。１材料和方法１．１供试棉铃虫１９９７～２０００年每年６月下旬至７月上旬，一代棉铃虫成虫大量迁入棉田时，于棉田设置杨树枝把诱蛾，对采…     

新疆棉区转Bt基因棉对棉田主要害虫及其天敌种群数量的影响

20 0 0～ 2 0 0 1年 ,在新疆棉区系统地研究了转Bt基因棉田主要害虫及其天敌的发生规律。结果表明 :转Bt基因棉对棉铃虫有良好的控制作用 ,发生高峰期百株落卵量和百株幼虫数量都显著低于常规对照 ,转Bt自控田和转Bt化防田棉蚜和棉盲蝽发生数量则显著高于常规棉对照田。在天敌方面 ,转Bt自控田和转Bt化防田较常规棉对照田 ,丽草蛉种群数量有所增加 ,而小花蝽和黑食蚜盲蝽等 5种捕食性和几种寄生性天敌数量都有所下降。转Bt基因棉田棉蚜和棉盲蝽等刺吸性害虫发生数量加重而多种天敌数量减少的趋势值得引起重视。鉴于新疆地区棉铃虫发生数量较低目前无需专门防治的特点 ,作者建议 :可以考虑推广农艺性状较好的常规棉品种并保护天敌 ,以达到控制害虫、丰产丰收的目的。     

甲基营养型芽胞杆菌AL7对棉花黄萎病的盆栽防治效果及定殖能力

为了探明甲基营养型芽胞杆菌AL7对棉花黄萎病的防治效果及其定殖能力,本文利用盆栽接种试验研究了菌株AL7对棉花黄萎病的防治效果;将带四环素抗性的pGFP78质粒转入到菌株AL7中,分析了菌株AL7在棉花根围土壤中、根部组织内的定殖情况。结果表明,菌株AL7对棉花黄萎病的盆栽防治效果为77.1%。pGFP78质粒转入后对菌株AL7的生长没有明显影响,仍具有游动性和产生物膜。定殖检测结果表明,菌株AL7能够在棉花根围土壤中及根系组织内长期定殖,接种5 d时定殖数量最高,达6×10~6cfu/g土,接种80 d后根围土壤中的定殖数量仍维持在2×10~6 cfu/g,根系组织内的定殖量为6×10~4 cfu/g。利用激光共聚焦显微镜观察验证,接种7 d后菌株AL7已经进入到棉花根部的中柱鞘细胞,能够在棉花根内大量定殖。     

棉花皱叶病毒分子检测方法

棉花皱叶病毒(Cotton leaf crumple virus,CLCrV)是典型的双生病毒,含A和B两个组分。根据B组分的保守序列设计的一对普通PCR引物,得到约为636 bp的片段,实验结果显示能特异性地扩增CLCrV B组分,棉花曲叶病毒(Cotton leaf curl virus,CLCuV)、非洲木薯花叶病毒(African cassava mosaec vi-rus,ACMV)、花椰菜花叶病毒(Cauliflower mosaic virus,CaMV)及番茄黄化曲叶病毒(Tomato yellow leaf curl virus,TYLCV)不干扰普通RCR方法对CLCrV的检测。设计的实时荧光PCR引物和探针也能特异性地检测棉花皱叶病毒,而CLCuV、ACMV和TYLCV不影响实时荧光PCR对CLCrV的检测。     

棉蚜对灭多威的抗性稳定性研究

将敏感棉蚜用灭多威选育２０代,获得抗性倍数达１４２．３７的高抗种群,在连续数代不接触药剂的情况下,其抗性水平呈下降趋势,停药１２代后抗性基本稳定,但高于敏感种群５倍,以该种群进行恢复试验,其抗性发展速度更快,恢复８代时抗性出现突增,２０代时抗性倍数达３８３．６７。     

短稳杆菌对棉蛉虫防控效果综述

棉蛉虫是棉花主要害虫之一。为了验证短稳杆菌杀虫剂对棉花棉蛉虫的防控效果,以苏云金杆菌16000IU/mg可湿性粉剂1500g/hm2为对照剂量,用短稳杆菌100亿孢子/mL悬浮剂对棉蛉虫进行了2年4地药效试验,结果表明,短稳杆菌100亿孢子/mL悬浮剂750~1250mL/hm2剂量对棉蛉虫有较理想的防控效果,且对棉花及其他非靶标生物安全,具有较好的推广应用价值。     

Overwintering of alternaria macrospora in Cotton Debris

An epidemic ofAlternaria macrospore in cotton started 1 month earlier, and developed faster in plots contaminated withA. macrospora-infected cotton debris than in debris-free plots. Overwintering of the pathogen in debris was associated with survival of the debris itself. With the exception of debris in dry soil, overwintering was better in debris located on the soil surface than in that buried beneath the surface. Under all conditions it was better in dry than in wet soil and in sterilized than in unsterilized soil. Survival was associated with micTobial activity in the soil, was highest in pure sand and decreased progressively in sandy loam, heavy soil and peat. The survival in debris was highest in soil kept at 10°C and decreased progressively at 20, 30 and 40°C. Increasing the soil moisture content reduced survival. Overwintering was better in a cotton field that was not cropped during the winter than in a field sown with wheat between the cotton seasons. The rate of transfer of disease to seedlings from debris buried in soil was low except when debris was in contact with the seed. The main means of disease transfer was by airborne spores produced on debris located on the soil surface. These spores had low infectivity and caused few lesions, but the second generation of spores formed on these lesions was highly infectious.