小麦吸浆虫类似种幼虫的种类和发生量

自80年代以来,小麦吸浆虫再次猖獗为害,引起各级农业部门高度重视。近年我们在调查研究中,发现麦田存在与小麦吸浆虫同时混合发生的类似种,它们在形态、体色和一些习性上十分相似。幼虫体形小、蛆状,都具鲜明色彩,很像麦红吸浆虫Sitodiplosismosellana（Gehin）的幼虫橙黄色,也像麦黄吸浆虫Contariniatrifici（Kirbg）的幼虫黄绿色,在土壤里结茧越夏和越冬,采用淘土法可淘获较大数量的幼虫体。根据满恩（M0bh）氏以胸骨片的形态特征区别种的重要特征方法,经比较发现在陕西咸阳麦田吸浆虫类似种幼虫有5类10种。发生这些类似种幼…     

麦红吸浆虫不同监测与施药方法比较

【目的】筛选出与麦红吸浆虫危害程度关系密切的监测方法,以及合适的施药方法与药剂种类,为有效控制其危害提供依据。【方法】通过对淘土和黄板诱集两种监测方法所得虫量与小麦穗被害率和单穗虫口进行回归分析,确定其与危害程度的相关性;通过比较小麦孕穗期撒毒土、抽穗期喷雾施用吡虫啉和毒死蜱防治麦红吸浆虫后小麦穗被害率和单穗虫口,选出合适的药剂种类和施药方法。【结果】小麦穗被害率和单穗虫口均与黄板监测到的成虫数量线性相关,与淘土所获幼虫量不相关。喷雾法和撒毒土法施用2种药剂后小麦穗被害率和单穗虫口呈现相同规律,即毒死蜱喷雾<毒死蜱毒土<吡虫啉喷雾<吡虫啉毒土。其中喷施毒死蜱处理的穗被害率与对照相比减少79.55%。【结论】黄板诱集比淘土法更适合监测麦红吸浆虫危害情况,抽穗期是防治麦红吸浆虫的最佳时期,在此时喷施毒死蜱可有效控制其危害。     

七种杀虫剂对小麦吸浆虫和麦蚜防治效果研究

【目的】明确25%吡蚜酮SC、3%甲氨基阿维菌素苯甲酸盐ME、25%噻虫嗪WG、14%氯虫·高氯氟ZC、15%高氯·毒死蜱EC、2.5%高效氯氟氰菊酯EW和40%毒死蜱EC 7种杀虫剂对小麦吸浆虫和蚜虫的防治效果,为科学、合理用药防治小麦害虫提供参考。【方法】采用喷雾法和剥穗调查法,研究它们对小麦吸浆虫成虫和麦蚜的防效,及防后对小麦吸浆虫幼虫危害损失的影响。【结果】参试药剂药后1 d对小麦吸浆虫成虫防效均高于90%,药后3~5 d防效为84.81%~93.93%,防后挽回损失76%以上;对麦蚜药后1、3、5 d防效分别高于75%、80%和85%。在供试的7种药剂中,15%高氯·毒死蜱EC药后3~5 d对两种害虫防效、挽回吸浆虫危害均超过90%,应用效果最好;其次为25%噻虫嗪WG和40%毒死蜱EC,药后3~5 d对吸浆虫防效高于90%、对麦蚜防效分别高于86%和90%,挽回吸浆虫危害损失88%以上。【结论】供试药剂对小麦吸浆虫和麦蚜防效存在显著差异,15%高氯·毒死蜱EC对两种害虫防治效果最好。     

不同抗性小麦品种上麦红吸浆虫幼虫的空间分布型与理论抽样数

【目的】为了解小麦品种抗性对麦红吸浆虫Sitodiplosis mosellana(Géhin)幼虫在麦穗上空间分布型的影响,为科学调查提供合理的抽样依据。【方法】2015年5月采用剥穗调查法对陕西省周至县试验田种植的4个抗虫和4个感虫小麦品种麦红吸浆虫幼虫危害进行调查,应用6种聚集度指标和Iwao M*?m回归法综合分析了幼虫在抗性不同小麦品种上的的空间分布结构。【结果】幼虫在抗、感小麦品种整穗及麦穗上、中、下部位上空间分布型一致,均呈聚集分布,但在抗虫品种上聚集强度大于感虫品种;抗、感小麦品种上分布的基本成分均为个体群,个体间相互吸引。聚集均数λ分析表明,幼虫在抗性较强品种上的聚集主要由小麦穗部化学物质和形态结构等环境因素引起,感虫品种上则由环境因素和成虫的产卵习性共同作用所致。幼虫在抗、感小麦品种上的发生趋势一致,均是上部发生最重,中部次之,下部最轻。根据Iwao回归法中的分布型参数,确立了幼虫在不同虫口密度和允许误差条件下的理论抽样数。【结论】麦红吸浆虫幼虫在抗性不同小麦品种上均呈聚集分布,调查时应根据当地栽培品种平均虫口密度选择适宜的抽样数量。     

小麦吸浆虫空间格局参数及其应用

本文应用聚集度指数、分析表明了小麦吸浆虫在麦田中的空间格局呈负二项分布,并探讨了吸浆虫在田间的聚集原因以及小麦吸浆虫穗虫平均密度（ｘ）与负二项分布公共ｋｃ值的关系。     

河南濮阳市小麦吸浆虫发生规律的调查与防治

调查了河南省小麦吸浆虫病的发生和分布情况,分析了小麦吸浆虫的发生与小麦品种、土质的关系,并成功地防治了小麦吸浆虫的大面积发生。     

小麦吸浆虫调查研究

<正> 近年来,小麦吸浆虫的为害程度严重回升,对小麦生产带来一定威胁。在孝感、云梦、应城、汉川、安陆等地调查发现:严重田虫穗率达90.17％,一穗上幼虫最多达106头,一粒中最多17头,损失率高达40％以上。我们于1985～1986年对该虫做了调查研究,现总结如下。 一、发生及为害 孝感地区小麦吸浆虫主     

太行山前平原麦田昆虫种类调查及4种药剂对麦红吸浆虫的药效实验

以藁城为例,采用淘土、扫网、挂黄板等方法对太行山前平原麦田昆虫群落进行了调查,结果表明该区域超高产麦田昆虫种类相对较少,总计22种,隶属于6目14科。害虫主要有2类,吸浆虫类和麦蚜类。小麦吸浆虫以麦红吸浆虫为主。天敌昆虫常见有蚜茧蜂、食蚜蝇、草蛉和瓢虫4类。采用氧乐果、毒死蜱、高效氯氰菊酯、吡虫啉4种常用药剂对麦红吸浆虫成虫进行了田间药效实验,结果表明上述4种药剂对麦红吸浆虫均有较好的防治效果,虫口减退率均在80%以上。其虫口减退率从高到低依次为:氧乐果、毒死蜱、高效氯氰菊酯、吡虫啉。建议根据麦红吸浆虫的发生情况,选择中低毒药剂毒死蜱、高效氯氰菊酯、吡虫啉交替使用。     

小麦品种抗麦红吸浆虫鉴定与抗性分析

利用一套较完整的田间自然感虫鉴定法,对183份小麦品种进行了抗麦红吸浆虫鉴定.鉴定结果表明,小麦不同品种对麦红吸浆虫的抗性存在着显著差异:高抗、中抗、低抗、感虫、高感的小麦品种,分别占参试品种的24.59%、16.94%、18.58%、14.21%、25.68%.不同抗性类型的小麦品种其穗被害率、粒被害率、估计损失率、抗性指数均有较大的差异,其中表现高抗类型45份,中抗类型31份.这些品种既可作为麦红吸浆虫发生区控制麦红吸浆虫危害的主推品种和后备品种,也可作为亲本材料提供给育种单位利用.     

小麦品种冀麦24抗麦红吸浆虫QTL分析

麦红吸浆虫是影响小麦产量和品质的重要害虫,研究小麦对吸浆虫抗性的遗传及其连锁分子标记对于提高抗虫品种的选择效率具有重要意义。本研究以小麦感虫品系6218与抗虫品种冀麦24产生的重组近交系(RIL)群体为材料,利用SSR标记和人工虫圃对冀麦24的抗虫性遗传进行了研究。结果表明:6218与冀麦24的抗性差异显著,RIL群体在2年2点的鉴定中抗性稳定;所构建的遗传连锁图谱包含112个SSR位点,形成26个连锁群,图谱全长835.7 cM,标记间平均距离为7.5 cM。利用QTL IciMapping的完备区间作图法,在4A染色体上检测到1个加性效应位点(QSm.hbau-4A),该位点在2个鉴定年度的贡献率分别为9.67%、10.57%。该抗性QTL及其连锁SSR标记的发掘,将有助于提高小麦抗吸浆虫育种的选择效率。     

SOIL SAMPLING FOR WHEAT-BLOSSOM MIDGES

A method of assessing the population of wheat-blossom midges by the recovery of the cocoons from soil is described.
In the dry summer of 1947, considerable numbers of larvae of Sitodiplosis mosellana Géhin were still in the ears at the time of harvesting. Burning the straw immediately after combining may considerably reduce the numbers of midges.
The majority of the larvae are found in the top 3 in. of the soil although a considerable number may be found from 3 to 6 in. Headland infestations may be lighter than the rest of the field.
Cocoons of S. mosellana remain viable in the soil for several years, and 150,000 per acre were recovered in February 1951 from a field which had not had a wheat crop since 1944. At the same time 50,000 Contarinia tritici Kirby cocoons per acre were found in a field which was last under wheat in 1947.
Viable pupae were successfully obtained by soil sampling, and the pupation in the soil and subsequent emergence of the midges can be followed. Thus it is possible also to estimate the numbers of midges that will emerge.
Progress has been made towards predicting outbreaks of these two midges.     

STUDIES OF FLUCTUATIONS IN INSECT POPULATIONS XIII. AN IMPROVED METHOD OF ASCERTAINING THE CORRECT DATE TO SAMPLE WHEN ASSESSING LARVAL INFESTATIONS OF THE WHEAT-BLOSSOM MIDGES

Fully fed larvae of the wheat-blossom midges need moist conditions in order to descend from the ears to the soil. A dry spell coinciding with the fully fed stage therefore causes an accumulation of larvae, which subsequently leave the ears in a body when rain comes. Conversely, in wet weather each larva leaves the wheat as soon as it finishes feeding, and, since all the eggs are not laid on the same day, the descent will then be a gradual process.
A method is described of taking small samples of wheat ears at frequent intervals, thus facilitating the determination of the correct date on which to take the main sample for the assessment of infestation by the two wheat-blossom midges.     

STUDIES OF FLUCTUATIONS IN INSECT POPULATIONS XII. FURTHER EVIDENCE OF PROLONGED LARVAL LIFE IN THE WHEAT-BLOSSOM MIDGES

Contarinia tritici emerges the same year as the larvae are in the wheat ears and up to 3 years later. Its parasites emerge up to 2 years after the larvae are in the wheat ears, but never the same year. This indicates that the supernumerary generation of C. tritici that occurs on couch grass in August and September may be expected to be free from parasites and so constitutes a dangerous source of replenishment of the pest.
Emergence of Sitodiplosis mosellana can take place after the larvae have been in the soil up to twelve winters. Most of any one year's larvae do not necessarily emerge as midges after one winter, although usually this is so. Any one year's flight is probably a composite one derived from several previous generations of this one-generation-a-year gall midge.     

耕作方式对麦红吸浆虫种群动态的影响

为了解不同耕作方式对麦红吸浆虫Sitodiplosis mosellana （Géhin）种群动态的影响, 2010年和2011年, 在中国科学院河北省栾城农业生态系统试验站不同耕作方式的小麦样地中, 通过淘土、 成虫网捕和剥穗等方法对麦红吸浆虫进行了调查研究。结果表明： 两年取土筛检出的幼虫数量依次为秸秆还田免耕田>秸秆站立免耕田>秸秆还田旋耕田, 但2011年网捕调查显示, 秸秆还田旋耕田中的成虫数量高于另外两种样地。两年剥穗检查出的幼虫数量的排序与取土筛检出的幼虫数量的排序相反, 依次为秸秆还田旋耕田>秸秆站立免耕田>秸秆还田免耕田。分析表明免耕有利于幼虫的越冬, 但免耕田麦穗受害较轻。旋耕对幼虫越冬不利, 但抽穗后受害较严重。在耕种方式是旋耕的情况下, 漫灌可加重吸浆虫的危害。研究结果有助于进一步了解大范围耕作方式的变迁对麦红吸浆虫发生的影响。     

小麦吸浆虫滞育幼虫甘油含量的季节变化(英文)

采用比色分析方法测定了小麦吸浆虫Sitodiplosis mosellana滞育期间幼虫甘油含量的季节变化。结果表明,幼虫离穗入土以前,甘油含量很低,仅为2.96±1.19μg/mg。幼虫离穗入土后,甘油含量急剧升高。入土后5d,甘油含量即上升为6.58±1.11μg/mg;至入土后17d,甘油含量达到高峰,12.21±2.21μg/mg。以后随时间的短期变化其含量变化不大,但随季节变化表现了一定的规律性,呈现了上升——下降——再上升——再下降的变化趋势,即夏季和冬季含量较高,秋季和春季含量较低。结茧幼虫和裸露幼虫比较,结茧幼虫的甘油含量在盛夏和冬季略高于裸露幼虫,秋季和春季时二者含量相当,两者在统计学上并无显著的差异。同一季节的当年滞育幼虫和进入第2年滞育幼虫的甘油含量无明显差异。由此可见,小麦吸浆虫幼虫滞育期间,甘油含量受季节或滞育深度的影响较大。     

CHANGES OF GLYCEROL CONTENT IN DIAPAUSE LARVAE OF THE ORANGE WHEAT BLOSSOM MIDGE, SITODIPLOSIS MOSELLANA (GEHIN) IN VARIOUS SEASONS

Abstract  The glycerol contents in diapause larvae of the orange wheat blossom midge, Sitodiplosis mosellana (Gehin), collected from various seasons, were measured. The results showed that there was less glycerol content in larvae during living on the wheat head. Content of glycerol began to increase significantly when the larvae left the wheat head and entered the soil. A change trend of upper- lower- upper- lower in larvae glycerol contents during diapause in soil was observed from June to April of next year. More glycerol could be examined in larvae collected in summer and winter than in spring and autumn. There was not more glycerol in cocooned larvae than that in non-cocooned larvae during various seasons from the point of statistics. Comparing the glycerol content of larvae being diapause in the first year with that of larvae in the second year, there was yet no obvious difference when larvae were collected in the same season belonged to different years. Therefore, it is shown that the content of glycerol in larvae of the wheat midge in diapause is affected mainly by the seasons or diapause intensity.     

OBSERVATIONS AND EXPERIMENTS ON THE HESSIAN FLY (MAYETIOLA DESTRUCTOR SAY)

Experiments showed that a stem midge collected locally on couch grass ( Agropyron repens ) and similar midges collected on wheat, barley and rye were of the same species, i. e. the hessian fly, Mayetiola destructor Say. There were three main flights per year, with some overlapping of the generations. In experiments, Aegilops ovata, Triticum compactum, T. dicoccoides, T. durum, T. spelta and T. turgidum were successfully used as host plants besides wheat, barley, rye and couch grass. Individual female midges when moved from plant to plant gave rise to families on the different host plants; similarly, succeeding generations of midges were able to breed on various host plants other than those from which they themselves were reared. Oviposition also took place on plants on which larvae failed to establish themselves.
Wheat seemed more favourable for the hessian fly than couch grass, and more midges were reared from young plants than from mature ones.
Unisexual families occurred in about half the experiments. The following parasites were bred: Trichacis didas Walker, Eupteromalus? hemipterus Walker, Platygaster sp., Chrysocharis sp. and Tetrastichus sp.     

Hessian fly-associated bacteria: transmission, essentiality, and composition

Plant-feeding insects have been recently found to use microbes to manipulate host plant physiology and morphology. Gall midges are one of the largest groups of insects that manipulate host plants extensively. Hessian fly (HF, Mayetiola destructor) is an important pest of wheat and a model system for studying gall midges. To examine the role of bacteria in parasitism, a systematic analysis of bacteria associated with HF was performed for the first time. Diverse bacteria were found in different developmental HF stages. Fluorescent in situ hybridization detected a bacteriocyte-like structure in developing eggs. Bacterial DNA was also detected in eggs by PCR using primers targeted to different bacterial groups. These results indicated that HF hosted different types of bacteria that were maternally transmitted to the next generation. Eliminating bacteria from the insect with antibiotics resulted in high mortality of HF larvae, indicating that symbiotic bacteria are essential for the insect to survive on wheat seedlings. A preliminary survey identified various types of bacteria associated with different HF stages, including the genera Enterobacter, Pantoea, Stenotrophomonas, Pseudomonas, Bacillus, Ochrobactrum, Acinetobacter, Alcaligenes, Nitrosomonas, Arcanobacterium, Microbacterium, Paenibacillus, and Klebsiella. Similar bacteria were also found specifically in HF-infested susceptible wheat, suggesting that HF larvae had either transmitted bacteria into plant tissue or brought secondary infection of bacteria to the wheat host. The bacteria associated with wheat seedlings may play an essential role in the wheat-HF interaction.     

Characterization of a serine carboxypeptidase in the salivary glands and fat body of the orange wheat blossom midge, Sitodiplosis mosellana (Diptera: Cecidomyiidae)

A full-length cDNA encoding a serine carboxypeptidase (designated SmSCP-1) was recovered from an ongoing salivary gland EST project of the wheat midge. The deduced 461-amino acid sequence had a putative signal sequence at the amino terminus, indicating it was a secreted protein. The protein shared homology with serine carboxypeptidases from other insects, mammals, plants, and yeasts. SmSCP-1 mRNA was expressed in all stages of development and detected in salivary gland and fat body tissues but not in midgut tissue. Expression analysis and quantitative real-time PCR assays in male and female wheat midges and the fat body tissue of adult midges revealed that SmSCP-1 was up-regulated nearly four-fold in the female midges compared to males and nearly two-fold in female fat body compared to male fat body. The wheat midge serine carboxypeptidase (SmSCP-1) most likely has a dual function. As a secreted digestive enzyme, it could play a role in mobilizing host-plant seed reserves for feeding larvae and as expressed in fat body could function as an exopeptidase in degradation of vitellogenin and/or in post-translational processing of other enzymes.     

Study on Relationships between Habits and External Structures in Oligotrophidi Larvae (Diptera, Cecidomyiidae)

Relationships between larval habits and external structures in last instar larvae in the Oligotrophidi were studied. More than one hundred species distributed among approx. 25 genera were examined. For comparison, literature records of larval habits and structural features referring to other taxonomic categories of gall midges were also evaluated. – The external larval morphology in the Oligotrophidi seems in several respects to be more specialized in various species whose larvae are solitary or are pupating regularly on the host plant than in the great majority of species with gregarious larvae pupating in the soil. Thus, the lateral papillae on the thorax and the ventral papillae on the abdominal segment 8 show a reduced pattern mainly in species whose larvae are solitary. Generally, species pupating in the soil possess a well-developed spatula sternalis while various species with solitary larvae regularly pupating on the host plant show a more or less transformed spatula or no spatula at all. Mamelons on the ventral body side, probably organs facilitating locomotion, are conspicuous in most species pupating in the soil but small or lacking in many species with solitary larvae pupating on the host plant. Another difference, a body which is less elongated in several species showing solitary habits than in the remaining species studied in the present context, is possibly also connected with the mode of life. – Gall midges of other taxonomic categories of a higher rank show similar tendencies, as regards both the lateral papillae and the spatula sternalis. However, there seems to be no clear correlation between larval habits and the pattern of ventral papillae on the abdominal segment 8. Definite figures relating to mamelons or body shape in these midges are not available. – The study also yielded many examples of a large intra-specific variation in some external structures of the larvae. In many cases this variation considerably delimits the possibilities of finding consistent distinguishing characteristics at species level.