共查询到18条相似文献，搜索用时 596 毫秒
1.
稻纵卷叶螟(Cnaphalocrocis medinalis Guenée)原在我县稻区偶有发生,六十年代逐年上升,七十年代大量发生,现已成为水稻主要害虫之一。为此,测报工作者们正在从不同途径探索回归预测式。 笔者用本县病虫测报站15年积累的资料,对稻纵卷叶螟一代幼虫与二代蛾量的关系进行统计分析,得出一个回归预测式,现提出供参考。 相似文献
2.
稻显纹纵卷叶螟Cnaphalocrocis exigua(Butler)是稻纵卷叶螟Cnaphalocrocis medinalis(Guenée)的近缘种,目前主要在我国西南稻区发生为害。为了明确稻显纹纵卷叶螟在四川省犍为县冬后的虫源状况,我们开展了稻显纹纵卷叶螟冬后虫源结构调查,观察了冬后种群的生物学特性,并研究了温度对其的影响。结果显示,犍为县舞雩乡和罗城镇稻显纹纵卷叶螟冬后虫源密度分别为7.09头/25丛和5.50头/25丛。调查时稻显纹纵卷叶螟主要以蛹为主,有少量幼虫。稻显纹纵卷叶螟越冬代雌雄蛹重分别为11.56 mg和11.82 mg,性比(雌∶雄)为1.29∶1,蛹被寄生率为16.5%。20℃、22℃、24℃和室温下稻显纹纵卷叶螟越冬代蛹羽化率分别为44%、38%、52%、43%。不同温度下,稻显纹纵卷叶螟产卵量及成虫寿命无显著差异。本研究结果对于开春稻显纹纵卷叶螟的防控具有指导意义。 相似文献
3.
4.
为掌握我国水稻各产区害虫的发生形势和防控现状,为分区域治理提供科学依据,本文分析了11年来水稻五大产区(华中稻区、西南稻区、华南稻区、东北稻区和华北稻区)的二化螟、三化螟、稻纵卷叶螟、褐飞虱、白背飞虱和灰飞虱的发生及防控情况,并进行了差异比较分析。结果显示：二化螟、稻纵卷叶螟、褐飞虱和白背飞虱是我国水稻的主要害虫。五大产区的害虫发生情况不同,二化螟在东北稻区、西南稻区和华北稻区整体发生较重;“两迁”害虫(稻纵卷叶螟和稻飞虱)在华中稻区、华南稻区和西南稻区发生较重。水稻病虫害防控主要通过化学防治,应进一步提升物理防治和生物防治比重,推进水稻绿色防控技术的普及应用。 相似文献
5.
6.
7.
转cry1Ab基因粳稻对稻纵卷叶螟成虫产卵行为的影响 总被引：1，自引：1，他引：0
为评价转cry1Ab基因粳稻(KMD1和KMD2)对稻纵卷叶螟Cnaphalocrocis medinalis(Guenée)成虫产卵行为的影响,采用"Y"型嗅觉仪和笼罩以及田间试验等方法对稻纵卷叶螟成虫对转基因水稻的趋性以及其产卵选择性进行了研究,并利用固相微萃取和GC-MS技术测定了这2种Bt水稻及其对照亲本秀水11挥发物的组成及其相对含量。结果表明,稻纵卷叶螟成虫在"Y"型嗅觉仪和小型笼罩内对Bt水稻和对照亲本的选择性差异不显著,而在大型笼罩和田间条件下均显著趋向于在非转基因水稻上产卵,其中大田中稻纵卷叶螟在KMD1、KMD2和对照中的百叶卵量分别为2.20±1.28、1.00±0.77和5.60±2.16粒。水稻挥发物的组成及其相对含量在Bt水稻及其对照亲本之间差异不显著。表明相对于Bt水稻,在田间条件下稻纵卷叶螟成虫趋向于在非转基因水稻产卵,而水稻挥发物可能不是引起这种行为趋性的直接原因。 相似文献
8.
9.
10.
11.
利用人工接卵和田间自然诱发鉴定1026个水稻品种(系)对稻纵卷叶螟的抗性,筛选出27个具有不同程度抗性的品种(系),其中黄金波品种可作为杂交育种的抗源,西海89品种具有抗病(穗颈瘟)以及丰产性好等特点,很有利用价值。此外,对抗性机制进行了初步研究和讨论. 相似文献
12.
不同稻田生态系统中稻纵卷叶螟、稻飞虱及其天敌密度的差异 总被引：6，自引：5，他引：1
研究了施用化学农药防治害虫的常规管理稻田和充分发挥天敌自然控害作用为主要防治害虫措施的稻田生态系统内稻纵卷叶螟、稻飞虱及其天敌的发生消长动态,以明确不同稻田生态系统对稻区内主要害虫及其天敌的影响.结果显示,生态调控区稻田内稻纵卷叶螟和稻飞虱最大高峰期虫量仅分别为常规管理区的0.51倍和0.63倍;生态调控区稻周植被上稻纵卷叶螟和稻飞虱发生数量几乎为0,而常规管理区最大高峰期虫量分别达到 23.61头/10网和82.03头/10网.生态调控措施还可以显著增加天敌数量,生态调控区稻田内最大高峰期天敌数量为常规管理区的3.72倍,其稻周杂草上最大高峰期天敌数量为常规管理区的5倍以上;同时,天敌与稻纵卷叶螟和稻飞虱发生高峰期吻合度远高于常规管理区.说明生态调控措施能充分发挥稻田及周边非稻田生境的保益控害功能. 相似文献
13.
14.
Biology of Southern rice black‐streaked dwarf virus: a novel fijivirus emerging in East Asia 
下载免费PDF全文
下载免费PDF全文 Southern rice black‐streaked dwarf virus (SRBSDV) was first reported in southern China in 2001 and causes a striking disease on rice and maize that leads to serious yield losses in several East Asian countries, such as China, Vietnam and Japan. A large research effort has been directed to understanding the virus and controlling the disease. Its geographic distribution, disease cycle via its insect vector, genome organization, relationship with host plants, and epidemiology are summarized in this review and the important role played by the vector, the white‐backed planthopper (Sogatella furcifera), is emphasized. Countermeasures to control the disease that have been developed and applied include molecular detection for precise forecasting, chemical, physical, and ecological pest management. There is widespread insecticide resistance in the vector population but it is hoped that current efforts to develop rice cultivars resistant to the virus will eventually provide effective and cost‐effective control. 相似文献
15.
根据稻纵卷叶螟Cnaphalocrocis medinalis Guenee对水稻危害的特点,作者对不同虫量的危害程度与水稻产量损失的关系,进行了测定和分析。结果表明:危害平均严重度或危害指数与产量损失呈平衡动态关系,空壳率的上升是产量损失的直接原因,其防治费用与产量损失金额相等时的经济阈值为:X_1=(1/(0.243))ln((1.7102CN+C_1)/(4.9034CN)(卷叶率)一般田块,防治指标的虫口密度为百株3.19—4.92头二、三龄幼虫。 相似文献
17.
近年来,稻纵卷叶螟已成为害水稻的重要害虫。结合生产实际,介绍稻纵卷叶螟的发生、分布、危害情况,重点讨论了控制稻纵卷叶螟发生的新方法和技术,指出存在的问题及对策。 相似文献
18.
Action thresholds as decision tools for insecticide application were developed and tested against the major insect pests of rice at four sites in the Philippines over a 13-year period. Action threshold treatments were compared to the farmers' practice, prophylactic insecticide usage, and an untreated check. Yield loss data using the insecticide check method partitioned yield losses over three crop growth stages in the same test fields. Chronic pests that exceeded action thresholds in 79% of fields were whorl maggot Hydrellia philippina Ferino (Diptera: Ephydridae), defoliators Naranga aenescens Moore and Rivula atimeta (Swinhoe) (Lepidoptera: Noctuidae), leaffolders Cnaphalocrocis medinalis (Guenée) and Marasmia patnalis Bradley (Lepidoptera: Pyralidae), and stemborers Scirpophaga incertulas (Walker) and S. innotata (Walker) (Lepidoptera: Pyralidae). Minor chronic pests reached threshold levels in only one site each: rice bug Leptocorisa oratorius (F.) (Koronadal), whitebacked planthopper Sogatella furcifera (Horvath) (Zaragoza) and green leafhopper Nephotettix virescens (Distant) (Guimba); brown planthopper Nilaparvata lugens (Stål) did not exceed a threshold in any field. Stemborers were the most important pest group in terms of yield loss. Despite the insecticide check method underestimating losses, a mean crop loss of 0.62 t/ha was measured which showed ample scope for corrective action. But loss was evenly distributed across crop growth stages (0.15?–?0.24 t/ha) reducing the impact of insecticides. Action threshold treatments overall outyielded the untreated check, more so in the two sites with highest pest density. The benefit of thresholds was to reduce insecticide usage, as a cost saving. However all the practices showed poor economic returns including the farmers' practice. Farmers' practice employed low insecticide dosages and timing was not consistent with pest damage, but yields were often similar to threshold treatments. Farmers appear to use insecticide more for risk aversion than for profit. The best threshold characters when evaluated against resulting pest density and yield loss criteria showed accuracies >?90% correct decisions. Future work is needed to improve the insecticide response rather than monitoring tools. Thresholds need to be incorporated into improved crop management, which was often found suboptimal by farmers, to take advantage of the high levels of tolerance in modern high tillering cultivars. Crop husbandry practices which improve yield potential such as selection of longer maturing varieties and nitrogen fertilizer may be a more effective pest management strategy than insecticides. 相似文献