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1.
在棉株结铃前,红铃虫一代卵主要分布于棉株新展开叶上。在棉花单株结铃害2.5个左右时,红铃虫卵均集中分布于棉青铃上,红铃虫二、三代卵分别以由外到内第二、三和第三、四大铃圆锥体位上的青铃卵量分布最多,分别占全株卵量的58.56%和67.19%。红铃虫在10天以上日的青铃上均可产卵,其中在20-34天日龄的青龄上产卵量最大,占青铃上总卵量的55.02%。一代和二、三代铃虫卵常分别1-8粒和1-3粒聚产成 相似文献
2.
棉红铃虫为害棉铃的损失估计 总被引:1,自引:0,他引:1
棉红铃虫 Pectinophora gossypiella (Saunders)幼虫为害棉铃所造成的损失估计,曹赤阳等曾作过报道。但用该逻辑斯蒂公式只能估计天气干旱、僵瓣很少的年份才接近实际损失。而红铃虫为害棉铃所造成的损失包括两个方面,其一幼虫侵入籽棉,使棉纤维的发育受 相似文献
3.
棉红铃虫田间产卵规律的研究及其在生产上的应用 总被引:1,自引:0,他引:1
红铃虫是一种为害棉花的大害虫,不但减少棉花产量,而且降低品质。黄河流域棉区因红铃虫为害损失棉花10%左右,长江流域棉区损失20—30%。因此,消灭红铃虫的为害,实为提高棉花单位面积产量和质量的一个重要环节。消灭红铃虫必须采取越冬期和田间的综合防治措施。过去指导田间药剂活期防治,主要依靠观察老熟幼虫的化蛹羽化和调查青铃的羽化孔,预测各代成虫羽化初期、盛期,以便发动群众进行田间喷药。但是 相似文献
5.
切断棉红铃虫食物链的探讨 总被引:1,自引:0,他引:1
根据棉花早蕾是一代棉红铃虫唯一食料,提出切断红铃虫食物链的构想。经多年实践,摘去7月上旬全部早蕾,能减少大部分蛀铃虫源,收到显著减轻或基本控制二代为害的效果,且能提高优质棉产量,使经济、生态、环境同步获益。 相似文献
6.
棉红铃虫自然种群的生命统计特征 总被引:1,自引:0,他引:1
1978-1988年,在湖北省江汉平原棉区,用编制特定年龄生命表的方法,研究棉红铃虫Pectin ophora gossypiella(Saunders),第1至3代的自然种群生命统计特征值。 世代存活率(占)为3.23,4.01和1.46;各虫态发育阶段(X)与相应阶段存活率的关系为:y1=61.66e-0.58s、Y2= 142.47e-0.73s、 y3=146.68e-0.80s种群鹃势指数(I):1.12、2.03和0.45;每雌蛾平均及最高产卵量:35(253)、51(235)、31(293)粒;自然内禀增长率(r')为0.0390、0.0403和0.0026;净增殖率?:4.39、4.43和2.04;周限增长率(兄):1.0398、1.0411和1.0026;世代长度(T):38、37和276日;种群加倍时间(t)18、l7和26,天。上列十个生命统计值已成为组建棉红铃虫的计算机辅助决策模型所必须的基质。 第二代是全年的关键世代,各代钻蛀期的幼虫数及越冬期的幼虫数是影响下一世代或次年种群数量的关键虫态,钻蛀期幼虫的自然死亡是致死的主导因子。 相似文献
7.
云南不同菜区小菜蛾的产卵规律与发育起点温度 总被引:1,自引:1,他引:0
在室内不同温度条件下(15~27℃,RH60%~70%),系统测定了云南不同菜区小菜蛾Plutella xylostella(L.)的产卵规律、发育起点温度和有效积温。结果表明,云南不同菜区小菜蛾的产卵规律、发育起点温度和有效积温有所不同,差异显著,呈现不同的区域性种群特征。(1)玉溪市通海县、昆明市呈贡县、红河州石屏县和曲靖市陆良县的小菜蛾单雌产卵量分别为213.0、182.5、132.2和71.6粒,区域间差异显著,以通海县小菜蛾种群的产卵量为最高,陆良县的最低;产卵天数分别为7.76、5.81、7.0和3.63d。(2)玉溪市通海县、昆明市呈贡县、红河州石屏县、曲靖市陆良县和大理州弥渡县的小菜蛾全世代发育起点温度分别为:(9.5±0.5)、(10.0±0.5)、(9.3±1.0)、(9.2±0.7)和(9.4±0.8)℃;有效积温分别为:(407.2±17.2)、(404.5±15.4)、(419.2±29.6)、(383.0±20.5)和(398.0±23.9)日·度。 相似文献
8.
长江流域棉红铃虫Pectinophora gossypeilla(Saunders)对棉花的经济损害主要是第二代卵孵化后的幼虫造成的。由于卵孵化后的幼虫很快就进入棉铃取食为害,给防治造成很大的困难,因此做好第二代田间卵量预测是整个棉红铃虫测报计划的关键。常规所采取的田间查卵。查花和查铃的方法,既费时费力,又常因人为因素带来较大的误差。性信息素监测棉红铃虫因其简单、灵敏、方便,已被许多测报部门采用,有些地方已积累了多年的资料,但仍没有完全取代传统的方法。本文对影响棉红铃虫第:二代卵的主要常用预报因… 相似文献
9.
本文以在浙江省宁波市镇海区进行的12年棉红铃虫(PectinophoragossypiellaSaunders)性信息素诱蛾试验为基础,通过相关分析,选取第一代蛾高峰期前累计诱蛾,棉花现蕾期和6月中旬到7月上旬的降水量3个参数,构建对第二代平均卵量进行综合评判的模型。由于多种因子对诱蛾量的影响具有不确定性和模糊性,采用FUZZY综合评判模型建模。以回报准确率为标准,对9种权重、4类评判矩阵和6种广义算子以及它们的特性作了比较和讨论。在构建的216个模型中,有94个模型的历史符合率达到100%。在这些模型的基础上,得到了一个优化评判模型。该模型与常规线性回归模型比较具有准确、方便、所含信息多等待点。在评判模型的基础上,增加第一次发现卵量的日期,构建了预报模型,该模型加强了预报的功能。模拟运行,可得到“预报速查表”;预测结果与大田相符。该研究为性信息素和其它行为调节物质在测报上的应用以及动态经济阈值的研究提供了一些新的思路。 相似文献
10.
血雉的产卵时间和产卵间隔 总被引:4,自引:0,他引:4
鸟类的产卵时间和产卵间隔因种而异 ,并会影响其繁殖成功。采用在巢内放置含有温度数据自动记录装置的假卵 ,通过记录其温度的变化来监测雌鸟产卵行为的方法 ,对分布于我国青藏高原森林鸟类血雉(Ithaginiscruentus)的产卵时间和产卵间隔进行了研究。结果表明 ,雌鸟每次入巢产卵的时间是在 15 :16± 2 2min (13 :30~ 18:5 1) ,产卵高峰集中在 14:0 0~ 16 :0 0 ,每次在巢中停留 (2 2± 0 2 6 )h。产卵间隔为 (46 4± 3 0 8)h ,大多数 (75 % )产卵间隔 45 8~ 48 9h。由此推测 ,血雉产卵时间较为集中很可能与避开夜行性捕食者的活动高峰有关 ;而隔天产卵则是对高原恶劣环境条件的适应。 相似文献
11.
Abstract: Field studies were conducted in Harran Plain, Turkey, to investigate the infestation of spiny bollworm (SBW) and pink bollworm (PBW) in cotton blind bolls during the period 1999–2001. Blind bolls left on the cotton plants after the harvest were collected, and the PBW and SBW larvae, which are the causes of infection were counted in the laboratory by splitting the bolls. The statistical methods reveal that the infestation ratio variable plays an important role in reducing cotton yield. The infestation ratio variable was found to be statistically significant in all models used. Different soil types may have little effects on yield. We also estimate elasticity of yield with respect to infestation ratio variable. A 1% increase in infestation ratio would reduce about 2.5–6% of cotton yield. Although the infestation ratio of cotton yield is inelastic, which means that the yield is less responsive to the infestation ratio, the elasticity is however an economically important indication because additional cost spent on pests will increase total cost thereby increasing the level where marginal revenue equals the marginal cost. 相似文献
12.
Thirteen polymorphic microsatellite markers were developed from an enriched partial genomic library for the pink bollworm, Pectinophora gossypiella (Saunders), one of the most important cotton pests in the world. The total number of alleles ranged from two to 12 for a sample of 50 individuals and the expected heterozygosity at these loci ranged from 0.042 to 0.830. Although the presence of null alleles in some loci is suspected, these polymorphic markers are likely to provide useful tools for the population genetic studies of this species. 相似文献
13.
通过应用灰色系统理论和方法,对彭泽县1960~1986年第三代棉红铃虫百株孵量构成的离散数列进行数据处理,用微分方程进行拟合,并建立棉红铃虫灰色系统GM(1,1)长期灾变预测模型:x(t)=53.60952e0.17851(i-1)1.97246e0.03736(i-1)-3.56687e-0.19052(i-1)-46.93949。应用该模型进行回测和预测,回测符合率可达100%,1987~1991年的预测结果与实况相吻合。 相似文献
14.
A diapause associated protein was electrophoretically isolated from the hemolymph of diapausing last instar larvae of the pink bollworm Pectinophora gossypiella. This protein (M(r) approximately 490,000, glycolipoprotein) was given the name Pectinophora diapause protein (PDP). It is composed of one subunit (M(r) 103,000). The concentration of PDP increased dramatically in the hemolymph of diapausing larvae from 17.4% in prediapause (PD) phase to 29.2% in early diapause (ED) phase reaching a level of 38.6% in larval hemolymph of middiapause (MD) phase. The concentrations of total proteins in the hemolymph of active feeding (A), PD, ED, and MD larvae were 69.8, 106,6, 113.3, and 118 mg/ml, respectively, while those in the fat body of the same larvae were 7.1, 7.4, 8.8, and 4.5 mg/g, respectively. In Pectinophora a drop in the concentration of fat body proteins coincided with a corresponding increase in hemolymph proteins, which suggests an active release of protein from the fat body into the hemolymph during the development of diapause. A partial amino acid sequence of pectinophorin showed the first 15 amino acids starting from the amino terminus of the peptide chain: N-ALA-LYS-THR-ILEU-VAL-GLU-ASN-MET-PRO-PRO-THR-PRO-LEU-ASN-ALA-C. 相似文献
15.
Female pink bollworm moths, Pectinophora gossypiella(Saunders), were selected for altered component ratios of the long-distance sex pheromone, (Z, E)-and (Z, Z)-7,11- hexadecadienyl acetate. Selection for 12 generations increased the mean (± SD) percentage of the (Z, E)isomer from 42.9 ± 1.0 in the parental generation to 48.2 ± 1.2. Although statistically significant, a change of this magnitude may be transparent to males because of their relatively broad response spectrum. Selection for a lower percentage of the (Z, E)isomer yielded no change in the mean pheromone ratio. The total amount of pheromone produced declined in both selected lines. In the line selected for females producing a high percentage of the (Z, E)isomer, the duration of wing fanning by males to high (Z, E)blends was elevated. 相似文献
16.
Tabashnik BE Liu YB de Maagd RA Dennehy TJ 《Applied and environmental microbiology》2000,66(10):4582-4584
Two strains of pink bollworm (Pectinophora gossypiella) selected in the laboratory for resistance to Bacillus thuringiensis toxin Cry1Ac had substantial cross-resistance to Cry1Aa and Cry1Ab but not to Cry1Bb, Cry1Ca, Cry1Da, Cry1Ea, Cry1Ja, Cry2Aa, Cry9Ca, H04, or H205. The narrow spectrum of resistance and the cross-resistance to activated toxin Cry1Ab suggest that reduced binding of toxin to midgut target sites could be an important mechanism of resistance. 相似文献
17.
Walters M Morrison NI Claus J Tang G Phillips CE Young R Zink RT Alphey L 《PloS one》2012,7(6):e38547
The cotton pest, pink bollworm (Pectinophora gossypiella (Saunders)), is a significant pest in most cotton-growing areas around the world. In southwestern USA and northern Mexico, pink bollworm is the target of the sterile insect technique (SIT), which relies on the mass-release of sterile pink bollworm adults to over-flood the wild population and thereby reduce it over time. Sterile moths reared for release are currently marked with a dye provided in their larval diet. There are concerns, however, that this marker fails from time to time, leading to sterile moths being misidentified in monitoring traps as wild moths. This can lead to expensive reactionary releases of sterile moths. We have developed a genetically marked strain that is engineered to express a fluorescent protein, DsRed2, which is easily screened under a specialised microscope. In order to test this marker under field conditions, we placed wild-type and genetically marked moths on traps and placed them in field cages. The moths were then screened, in a double-blind fashion, for DsRed2 fluorescence at regular intervals to determine marker reliability over time. The marker was shown to be robust in very high temperatures and generally proved reliable for a week or longer. More importantly, genotyping of moths on traps by PCR screening of the moths was 100% correct. Our findings indicate that this strain--and fluorescent protein markers in general--could make a valuable contribution to SIT. 相似文献
18.
Jianjun Wang Gregory S. Simmons Thomas A. Miller Bruce E. Tabashnik Yoonseong Park 《Journal of Asia》2011,14(1):131-135
The piggyBac transposable element, originally discovered in the cabbage looper, Trichoplusia ni, has been used widely in genetic engineering of insects including the pink bollworm, Pectinophora gossypiella, a major lepidopteran pest of cotton. Previously, we identified an intact copy of a piggyBac-like element (PLE) in pink bollworm, designated as PgPLE1.1. Here we report global variation in the occurrence and sequence of PgPLE1.1 and its flanking sequences. Low to high frequency of the PgPLE1.1 insertion was observed in populations from USA, Mexico, China, India, and Israel, while there is no PgPLE1.1 insertion in the populations from Australia. Investigation of the five haplotypes of PgPLE1.1, their frequency, and the flanking sequences of PgPLE1.1 revealed significant differences of the populations from Australia and China compared to other global populations, although recent occurrences of extensive gene flows among global populations were evident. 相似文献