Early assessment of the yield loss in rice due to the brown planthopper using a hyperspectral remote sensing method

The brown planthopper (BPH) is an important pest in rice. Rice losses due to BPH's damage are often more than 10% of yield. Assessments on loss rates from BPH are now basically dependent on experiential indices. However, early assessments on rice yield losses using hyperspectral data are still rare. In this study, reflectance from rice canopy was measured in net cages after different densities of BPH release. Results showed that reflectance in the near-infrared region (750–1000 nm) from milk grain stage, and in 400–531 nm and 567–705 nm from mature grain stage was closely related to BPH density. These spectral indices: red-edge parameters (λ_r, Dλ_r, Sλ_r), ratio of the maximal reflectance in green (490–560 nm) to minimal reflectance (640–740 nm) in red (R_GREEN/R_RED), ratio of the near-infrared peak (R_NIR) to R_RED, normalized difference vegetation index between R_NIR and R_RED and soil-adjusted vegetation index (SAVI) from both milk and mature grain stages, indicated BPH densities well. As expected, rate of loss in rice grain was higher with increasing BPH density. SAVI, Dλ_r, Sλ_r and reflectance at 760 nm (R₇₆₀) from milk grain stage were significantly correlated with rates of loss in panicle, and 1000-grain weight and multiple-linear regression models for detecting loss rate were established. The hyperspectral reflectance from rice at milk grain stage can be used to assess rice yield losses due to BPH and improve management policies.     

不同杀虫药剂对水稻“两迁”害虫田间药效研究

针对褐飞虱和稻纵卷叶螟（“两迁”害虫）化学防治药剂缺乏的现状,2013年对新烟碱类、三嗪酮类、几丁质合成抑制剂类、氨基甲酸酯类等6种杀虫药剂对褐飞虱以及双酰胺类、大环内酯类、缩氨基脲类、有机磷类等9种药剂对稻纵卷叶螟进行田间防治效果评价。结果表明,施药后5 d和10 d,氟啶虫胺腈、呋虫胺、噻虫嗪、吡蚜酮对褐飞虱的防效分别为77.9%~90.9%和77.0%~90.5%,异丙威和噻嗪酮防效分别为40.1%~65.9%和20.6%~49.9%,氟啶虫胺腈、呋虫胺、吡蚜酮与异丙威、噻嗪酮防效差异显著。施药后14 d,茚虫威、四氯虫酰胺、氟苯虫酰胺、氯虫苯甲酰胺、氰氟虫腙防治稻纵卷叶螟的保叶效果都在80%以上,甲氨基阿维菌素苯甲酸盐为71.3%,溴氰虫酰胺、稻散×毒死蜱、丙溴磷保叶效果为62.2%~69.9%,茚虫威、四氯虫酰胺与丙溴磷差异显著;茚虫威、四氯虫酰胺、氟苯虫酰胺、氯虫苯甲酰胺、氰氟虫腙、甲氨基阿维菌素苯甲酸盐、丙溴磷、稻散·毒死蜱杀虫效果都在90%以上,与溴氰虫酰胺防效61.9%差异显著。建议在实践中,可轮换使用噻虫嗪、吡蚜酮、呋虫胺、氟啶虫胺腈防治褐飞虱,轮换使用双酰胺类、甲氨基阿维菌素苯甲酸盐、茚虫威、氰氟虫腙、有机磷类防治稻纵卷叶螟。     

水分胁迫下水稻对褐飞虱转录组的影响

为明确褐飞虱Nilaparvata lugens(St?l)在稻田缺水条件下的发生和灾变规律,以感虫水稻品种TN1为材料,以取食无水分胁迫水稻的褐飞虱为对照组,取食水分胁迫(以15%PEG6000营养液处理48 h模拟)水稻的褐飞虱为处理组,采用Illumina转录组测序技术研究水分胁迫下水稻对褐飞虱转录组的影响。结果显示,测序序列经拼接后得到褐飞虱全部单基因unigene共47 335条,平均长度为1 234 bp;与对照组相比,处理组中表达量差异显著的基因共有1 331条,其中表达量上调的基因有712条,表达量下调的基因有619条;随机选取20条具有显著表达差异的基因,通过实时荧光定量PCR方法检测其表达量以进行验证,其中有13条基因的表达量与测序结果变化一致。对差异表达基因进行GO注释和KEGG代谢通路功能富集分析表明,能量代谢和水分代谢相关通路在水分胁迫处理的褐飞虱中显著富集,表明这几类基因在褐飞虱应答水分胁迫中发挥了重要作用。     

水稻对褐飞虱和白背飞虱的抗性及其机制研究进展

作物品种抗虫性是害虫综合治理中重要的技术措施。筛选抗性材料和评价其抗性机制是作物育种和害虫综合治理的关键所在。本文综述了水稻品种对褐飞虱和白背飞虱的抗性及其机制,并介绍了抗稻飞虱的基因及其在育种上的应用。可为水稻抗稻飞虱品种的选育和利用以及稻飞虱的综合治理提供借鉴。     

褐飞虱和白背飞虱在抗褐飞虱水稻品种上的行为反应

以ASD7、IR36、粳籼89(JX89)、Mudgo四个抗褐飞虱水稻品种和感性品种TN1为材料,比较了褐飞虱和白背飞虱在这些品种上的行为反应。褐飞虱对抗性品种表现出明显的非嗜好性。褐飞虱自4h、白背飞虱自8h以后,各品种上的着虫量与TN1差异显著,而其它各品种上的虫量无明显差异(Mudgo除外)。白背飞虱选择各抗性品种的百分率明显大于褐飞虱(Mudgo除外);同一水稻品种上的稻飞虱数量无时间上的规律性。两种稻飞虱在抗性品种和TN1上的取食量差异显著。取食同一品种时,白背飞虱在IR36、JX89上的取食量大于褐飞虱,且相互间差异显著。两种稻飞虱在四个抗性品种上的取食痕数量明显多于TN1;两种飞虱在ASD7和JX89上的取食痕数量差异显著,白背飞虱的数量明显少于褐飞虱。在所有水稻品种上的取食痕数量与取食量呈明显的负相关关系。     

3种药剂防治晚稻褐飞虱试验

稻飞虱是桂林市水稻上最严重的害虫之一,历年发生严重,特别是最近几年,褐飞虱对吡虫啉类农药产生了很高的抗药性,防治效果明显下降。为筛选防治褐飞虱的高效药剂,作者在临桂县临桂镇秧塘村进行了晚稻田间防治褐飞虱试验,现将结果总结如下。1试验材料和方法1·1试验药剂40%万灵将SP,美国杜邦公司提供;20%好年冬EC,美国FMC公司提供;15%金好年EC,美国FMC公司提供;10%蚜虱净WP,江苏克胜集团生产(市售);25%扑虱灵WP,上海东风农药厂生产(市售)。1·2试验设计试验设40%万灵将SP 86g/667m2(约700倍),40%万灵将SP 43g/667m2 25%扑虱灵WP80g/…     

福建省褐飞虱发生特点浅析

收集整理福建省30年来褐飞虱发生及历年的气象资料,探讨了褐飞虱的发生特点及其与气候关系,旨在为该虫的预测预报、发生趋势分析以及可持续综合治理提供科学理论依据。     

环境因素对水稻品种抗褐飞虱的影响研究概况

褐飞虱是东南亚、东亚水稻产区的重要害虫。栽培丰产的抗虫水稻品种是防治该虫经济有效的措施之一,由于作物抗虫性是在一定的环境条件下寄主与昆虫相互作用的表现,不同环境条件对作物抗虫性有影响。本文从气候因素、土壤肥力因素、生物因素、人为因素、抗虫品种和褐飞虱及不同因素综合作用等几方面概述了环境因素对水稻品种抗褐飞虱的影响,并提出了有待于今后进一步研究的问题。     

早稻田白背飞虱和褐飞虱种群发生新态势

系统调查研究了近年白背飞虱和褐飞虱在粤西双季早稻田中的发生动态。结果表明 ,在广东肇庆地区早稻种植区稻飞虱田间种群一般 5月上旬、5月底到 6月初出现 2个发生高峰。近年白背飞虱成为早稻上稻飞虱中的优势害虫。在当地水稻栽培品种中以茉莉新占、山溪占类品种稻飞虱发生数量较高。     

几种药剂对稻褐飞虱的防效试验

试验结果表明:25%扑虱葳乳油600倍防治稻褐飞虱,药后3d、7d、14d防效分别达90.0%、97.95%、95.82%,是防治稻褐飞虱的理想药剂;40%毒死蜱乳油1 000倍 25%扑虱灵可湿性粉剂1 000倍防效也分别达91.80%、95.16%、91.57%,鉴于毒死蜱乳油成本较高,可将其作为防治稻褐飞虱的轮换药剂。     

不同水稻品种对褐飞虱的抗性对比

近几年来,水稻褐飞虱在我县一、二晚稻中连年重发生,为害损失逐年加重,是影响我县晚稻产量的重要因素之一。在化学防治过程中,由于连续重施杀虫剂,造成褐飞虱种群对常用的几种防治药剂产生了明显抗(耐)药性、天敌种群数量减少、防治成本提高和环境污染等诸多问题。预防和减轻     

Allelopathic potential of Cambodian rice lines under field conditions

A series of field experiments was conducted during 1999 and 2000 to study the effect of six Cambodian rice lines that had been selected for their allelopathic potential on the growth of three weed species (barnyardgrass, small umbrella sedge, and water primrose). The results from 2 years' study demonstrate that powerful weed‐establishment and growth‐suppressive mechanisms were present in all of the rice lines tested. This mechanism was equally active on all three weed species studied. Across all the rice lines and across all the weed species, weed establishment was reduced by 71%, the final plant height was reduced by 49%, and the dry biomass was reduced by 80%. A tentative comparison between the effects of the Cambodian rice lines and those of previously characterized allelopathic and non‐allelopathic rice lines revealed that approximately three‐quarters of the weed growth suppression in the Cambodian lines could be attributed to resource competition and one‐quarter could be attributed to allelopathy, although this analysis did not take into account morphological differences between the two types of rice. Such weed growth‐suppressing activity could be particularly useful in subsistence farming systems where the use of selective herbicides is prohibitive or when organic rice production is the objective. The use of rice lines that suppress the growth of weeds is likely to be a potent supplement to present weed management practises and will reduce production costs and the potential for environmental pollution, as well as alleviate some of the social constraints that are associated with labor‐intensive manual weeding.     

水稻抗虫品种对褐飞虱不同生物型若虫生长发育及翅型分化的影响

观察含有不同抗虫基因的水稻品种对褐飞虱生物型Ⅱ、孟加拉型、九龙江型若虫发育历期、存活、翅型分化的影响表明 :生物型Ⅱ若虫在抗虫品种Ptb33上无法羽化 ,在抗虫品种RathuHeenati上若虫发育历期最长 ,在抗虫品种ASD7、Babawee上和在感虫品种TN1、Mudgo上差异不显著 ;孟加拉型若虫发育历期在Ptb33上最长 ,在TN1、Mudgo和ASD7上最短 ;九龙江型若虫历期在Ptb33上最长 ,分别比TN1、Mudgo、ASD7、RathuHeenati和Babawee多 11.82、10.41、10.87、74.6、92.9d。生物型Ⅱ在抗虫品种上若虫存活率明显下降 ;孟加拉型除Babawee外 ,在RathuHeenati、Ptb33上若虫存活率很低 ,分别为 14 %和 4% ;九龙江型若虫在Ptb33上的存活率为 8% ,在RathuHeenati上的存活率为 28% ,在其余感虫品种上的存活率均达 52%以上。不同生物型在不同抗感品种上的短翅率均很高 ,受品种抗感性的影响不大。     

抗褐飞虱兼抗白背飞虱水稻种质资源发掘

为了发掘出对褐飞虱生物型Ⅱ、孟加拉型及白背飞虱具有抗性的稻种资源供抗褐飞虱兼抗白背飞虱育种选用,采用苗期群体鉴定法对383份水稻种质资源进行了抗性鉴定。发掘出107份抗褐飞虱兼抗白背飞虱的稻种资源。其中,抗褐飞虱生物型Ⅱ兼抗白背飞虱的稻种资源58份,占抗性鉴定总数的15.14%;抗褐飞虱孟加拉型兼抗白背飞虱的稻种资源49份,占抗性鉴定总数的12.79%。本研究发掘的107份抗褐飞虱兼抗白背飞虱的稻种资源,在育种时可作为亲本选用。     

不同水稻品种对褐飞虱的抗性鉴定

采用分蘖盛期单株鉴定法初步测定了183个水稻品种对褐飞虱的抗性,筛选出19个高抗水稻品种,然后用水稻苗期群体筛选鉴定法和成株期自然种群鉴定法,进一步测定了19个初筛鉴定的抗性水稻品种对褐飞虱的抗性反应,结果表明：2个水稻品种（江农早1号和三粒寸）在3种鉴定方法条件下均表现为抗性或免疫水平。     

锐劲特加入农药助剂丝润或杰效利防治水稻褐飞虱试验

2005年吴江市水稻生长后期,褐飞虱(Nilaparvata lugens)严重发生,对吡虫啉产生了684.6倍的抗性,因此,2006年吡虫啉在本市水稻生长中、后期全面停止使用[1]。     

80％锐劲特水分散粒剂防治晚稻褐飞虱、二化螟、稻纵卷叶螟药效试验

晚稻分蘖期通常同时受到褐飞虱、第3代二化螟、第5代稻纵卷叶螟的危害,选择几种广谱性高效农药进行防治,其中以80％锐劲特WG的综合防治效果较好,每667m^2施用3-4g,对褐飞虱、二化螟、稻纵卷叶螟的防治效果分别为84．71％～99．42％、90,57％～95。83％、93．95％～95．2％;48％乐斯本EC的综合防治效果次之,每667m^2施用150ml的防效分别为92．81％～72．25％,85．75％～93．38％;以上2种药剂的防治效果明显高于80％敌敌畏EC120ml加20％三唑磷EC 120ml的防治效果。