共查询到20条相似文献，搜索用时 15 毫秒
1.
Studies of cereal aphids and barley yellow dwarf virus (BYDV) from 1989 to 1992 revealed that Poa annua is an abundant weed of commercial winter barley crops during the summer months. P. annua was frequently infected with BYDV, and there were usually similarities with the BYDV infection of the surrounding barley crop. These P. annua weeds were often infested by cereal aphids both in July (pre-harvest) and in September (in cereal stubble fields). Poa -infested cereal stubbles may be major local sources of viruliferous aphids, increasing the risk of BYDV in nearby winter cereals. P. annua plays an important role in the epidemiology of S. avenae -transmitted BYDV. 相似文献
2.
R. A. Daamen W. Stol 《European journal of plant pathology / European Foundation for Plant Pathology》1993,99(Z3):51-56
Between 1980 and 1986, commercial winter wheat fields at the milky-ripe stage were surveyed for insect pests. Leaf injuring
insects were common. On average 42% and 95% of the surveyed fields were injured by leaf miners and the cereal leaf beetle,
respectively. On average 14% of the leaves was skeletonised by the cereal leaf beetle and leaf injury tended to be high in
seasons after winters with low temperatures. Blossom midges were the most important midges. In the period 1980–1984, the orange
and lemon blossom midge infested 71 and 21% of the surveyed fields, respectively, Insecticides were mainly used to control
aphids. Despite control, on average 80% of the fields and 22% of the tillers were infested by aphids. 相似文献
3.
Field trials were conducted in spring wheat to observe effects of jasmonic acid (JA) on aphids, thrips and wheat blossom midge (WBM). Two spring wheat varieties (Triso and Kadrilj) were sprayed twice, with two concentrations of JA plus control. Wheat pests and associated natural enemies (Coccinellidae, Empididae and Aphelinidae) were surveyed by direct count and sweep net methods. Thrips larvae and adults and WBM larvae were estimated by dissecting wheat ears. Wheat midge larvae were monitored using white traps in treated and untreated plots. At the end of season, wheat yield was assessed in treated and control plots. There was a significant difference in the number of insect pests and their natural enemies between treatments in both varieties. Plants in control plots had higher numbers of aphids, thrips and midges than in treated plots. There were more aphids, thrips and midges on the variety ??Triso?? than on ??Kadrilj??. JA application enhanced wheat yield in treated plots compared to control plots. The results indicated that JA mediated induction of plant defense in wheat plants can improve resistance against insect herbivores. JA could be used to develop environmentally sound crop management with reduced insecticide applications. 相似文献
4.
R.H. Bzrown 《EPPO Bulletin》1982,12(4):477-484
The effects of various cultural practices on cereal cyst nematode (Heterodera avenae) populations, and the subsequent yield of wheat, have been studied over many seasons in Victoria, Australia. Crop rotations which include periods of fallow, or of non-host crop reduce population levels and improve yields. The inclusion of a legume has the additional advantage of improving soil nitrogen levels. Early sown crops (April/May) are less severely damaged, and produce better yields, than late sown crops (June/July). The resowing of damaged wheat crops with either wheat or barley is not effective in improving yields, although cyst numbers are lower on resown crops. Nitrogenous fertilisers are not generally applied to cereals, and although small increases in yield are sometimes obtained, they are rarely economic. Sulphate of ammonia applications increase cyst numbers, especially when applied at seeding, but urea has only a marginal effect on cyst numbers. 相似文献
5.
The incidence of barley yellow dwarf virus and of its aphid vectors was surveyed in untreated parts of autumn-sown cereal crops, mainly wheat and barley, in the United Kingdom in 1995-8. The incidence of virus in the spring was related to the incidence of aphids in the preceding autumn. Both virus and aphid incidences could also be related to a range of crop and field characteristics, in particular sowing date, regions as defined by their geographical position, topography and climate, the proximity of the field to the sea, the extent of arable land in the vicinity of the field, and the aspect and size of the field. Proximity of cropped fields to setaside areas had no significant effect on either aphid or virus incidence. 相似文献
6.
Aphid feeding in cereals results in both quantitative and qualitative yield losses; moreover aphid-transmitted viruses are responsible for other quantitative and qualitative damage so that direct or indirect effects of aphid infection are always of interest. At the beginning of stem elongation, wheat plants were caged regardless of the presence or absence of indigenous cereal aphids. Half of the caged plants were artificially infected with Diuraphis noxia. The number of D noxia and Rhopalosiphum padi individuals on plants destined for flour preparation was approximately 150 aphids per tiller at peak population. The number of Sitobion avenae individuals was ca 25 aphids per tiller. Bread-making quality of wheat flour is determined primarily by the protein content, the gluten proteins (gliadins, glutenins) being the prime factors. The absolute amounts and/or the relative proportion of gliadins and glutenins are very important in dough making and in determining baking quality. Flour from grains originating from plants infected naturally with cereal aphids indigenous to Hungary, and flour infected artificially with D noxia, were analysed for glutenin and gliadin content using size exclusion HPLC. It was found that aphid infection had a significant effect on the gliadin/glutenin ratio, which was significantly lower in wheat flour prepared from aphid-infected plants than in that from uninfected control. The most significant decrease in gliadin/glutenin ratio was caused by D noxia infection, followed by R padi and then S avenae. As the gliadin/glutenin ratio was significantly lower in flour made from aphid-infected wheat seeds, it can be supposed that aphid feeding results in decreased bread making quality of wheat flour. 相似文献
7.
8.
Transmission of barley yellow dwarf virus by cereal aphids collected from different habitats on cereal farms 总被引：1，自引：1，他引：1
Cereal aphids were collected from cereal crops, from Poa annua within cereal fields, from Lolium perenne pastures and from wild grasses in hedge bottoms and around farm buildings. The frequency of barley yellow dwarf virus (BYDV) transmission was assessed by aphid transmission tests. There were differences in transmission rates between aphid species, between host species and between years. The transmission rates of Rhopalosiphum padi from the different host species were broadly similar whereas for Sitobion avenae, P. annua within cereal fields was significantly better than the other host species. Wild grasses other than P. annua were relatively poor sources of virus. A large percentage of aphids frequently transmitted more than one strain, suggesting that host plants are often infected with more than one BYDV strain. 相似文献
9.
Dr. Nabil E. El-Wakeil Abdellah S. H. Abdel-Moniem Nawal Gaafar Christa Volkmar 《Gesunde Pflanzen》2013,65(1):7-13
Orange wheat blossom midge damage can impart serious loss of quantity and quality of winter wheat. Wheat midges were evaluated in large scale field in winter wheat in Bad Lausick (Leipzig, Saxsony) central Germany. The present study aimed at studying the activity of wheat blossom midges WBM, Sitodiplosis mosellana (Géhin) and Contarinia tritici (Kirby) using pheromone, sticky traps and two types of water traps. Management of midges with different treatments was studied; Karate (pyrethroid), Biscaya (neonicotinoid) and NeemAzal T/S (botanical insecticide) were sprayed on wheat at heading stage (GS 55). Monitoring was conducted before the treatment and continued for 4 weeks after the treatment. Pheromone traps were used for forecasting midge adult population and determine the control date. Water traps were used to assess midge larvae, while midge adults were surveyed using sticky traps. A strong correlation between midge catches and weather conditions was obtained; as well a coincidence between pheromone catches and wheat midge infestation in the susceptible growth stages (GS 47–65) was recorded. Insecticide applications to fields of midge-infested winter wheat significantly reduced the wheat midge damage. There were significant differences in wheat midge numbers between treated and untreated; wheat midge numbers were lower in the treated than in control. The results proved that both Karate and Biscaya caused more mortality to wheat midges than NeemAzal T/S. 相似文献
10.
宁夏麦蚜天敌多样性及种间关系 总被引：1，自引：1，他引：0
麦蚜是宁夏小麦的主要害虫,为了实现自然天敌对麦蚜的有效控制,采用网捕法和陷阱法等采集手段,通过3年田间调查,共鉴定麦蚜天敌97种,包括寄生性天敌16种和捕食性天敌81种。将麦蚜天敌划分为单食性天敌、寡食性天敌、多食性天敌及杂食性天敌共4类功能团进行分析,结果表明,不同天敌功能团对麦蚜种群的影响存在显著的交互作用;寄生性天敌中蚜茧蜂属的燕麦蚜茧蜂与烟蚜茧蜂是优势种;捕食性天敌种类较为复杂,不同地区麦蚜天敌组成存在显著性差异,复杂的农业景观能够维持更高的天敌多样性。表明在农业生态系统中建立和恢复非作物生境能够明显提高天敌种群数量,进而提高其生物防治作用。 相似文献
11.
J. Gebauer 《Anzeiger für Sch?dlingskunde》2002,198(2):1-5
In Ireland, the grey field slug (Deroceras reticulatum) is the predominant slug pest species in arable crops. It can cause enormous damage, but the knowledge about its feeding biology is limited.Adult species were reared under laboratory conditions, and the survival, feeding activity, and weight change of slugs when feed on maize, peas, or wheat seeds were investigated. An especially high mortality was experienced in the wheat treatment. It was hypothesised that the high mortality was due to a Fusarium species, however, a Fusarium infection of the wheat seeds was not confirmed. The weight change of the slugs was very variable due to a high egg production of some slugs. 相似文献
12.
Basky Z 《Pest management science》2003,59(10):1152-1158
Russian wheat aphid, Diuraphis noxia (Kurdjumov) is a severe pest of cereals in South Africa and in the USA. In order to reduce D noxia damage, intensive resistance breeding programs have been undertaken, resulting in D noxia-resistant cultivars that are now widely used in South Africa and in the USA. However, there appear to be differences in the ability of different populations of D noxia to damage these resistant cereal cultivars. To determine whether different biotypes of D noxia are present, damage to eight wheat cultivars was compared when they were exposed to either Hungarian or South African aphid strains. It appeared that the Hungarian CVS MV Magdaléna, MV Magvas, and MV 17 were susceptible to D noxia from both Hungary and South Africa. The susceptible South African CV Betta was also severely damaged regardless of the country of origin of the aphids. None of the cultivars resistant in South Africa (Caledon, SST 333, SST 972 and Halt) were, however, resistant to Hungarian populations of D noxia. These cultivars, which carry resistance genes originating from the breeding lines PI 262660, PI 137739 and PI 372129, were severely damaged by the Hungarian D noxia. Apart from the highly resistant CV Halt, the resistant cultivars used in this study were developed in South Africa, with the biotype present there. Damage to all cultivars tested was significantly more severe in response to Hungarian than to South African D noxia, indicating that a more damaging aphid biotype occurs in Hungary. However, D noxia has not yet become a pest of wheat in Hungary, possibly due to a difference in cultural practices. 相似文献
13.
R. A. Daamen W. Stol 《European journal of plant pathology / European Foundation for Plant Pathology》1993,99(3):51
Between 1980 and 1986, commercial winter wheat fields at the milky-ripe stage were surveyed for insect pests. Leaf injuring insects were common. On average 42% and 95% of the surveyed fields were injured by leaf miners and the cereal leaf beetle, respectively. On average 14% of the leaves was skeletonised by the cereal leaf beetle and leaf injury tended to be high in seasons after winters with low temperatures. Blossom midges were the most important midges. In the period 1980–1984, the orange and lemon blossom midge infested 71 and 21% of the surveyed fields, respectively, Insecticides were mainly used to control aphids. Despite control, on average 80% of the fields and 22% of the tillers were infested by aphids. 相似文献
14.
E. D. WIlLLIAMS 《Weed Research》1977,17(1):69-76
As part of a programme of work evaluating the role of seeds in regenerating or initiating infestations of Agropyron repens and Agrostis gigantea, the growth of the weeds was analysed in cereal crops in two experiments. The first experiment investigated the effects of time of planting the weed seedlings (simulating different times of emergence), nitrogen supply and cereal seed rate in winter wheat and the second, the same factors in spring wheat and spring barley. In winter wheat, delaying planting of the weeds from autumn until spring greatly decreased shoot growth and almost completely prevented rhizome formation. Nitrogen fertilizer increased the weight of shoots of both species planted at both times but whereas it increased the amount of rhizome produced by Agropyron it decreased that of Agrostis. Without nitrogen Agrostis had twice as much rhizome as Agropyron but with nitrogen Agropyron had twice as much as Agrostis. Decreasing the cereal seed rate had little effect on rhizome weight when nitrogen was not given but it allowed twice as much rhizome to be produced when it was supplied. However, more longer rhizomes were formed at the smaller than at the larger seed rate with both amounts of nitrogen. In spring cereals, late planting decreased the shoot growth of Agrostis more than that of Agropyron, and of Agropyron in barley more than in wheat, especially at the smaller seed rate. Nitrogen increased shoot weight of Agropyron in wheat but had little effect in barley; it decreased that of Agrostis in barley. On average, rhizome growth was decreased by nitrogen, by increasing the seed rate and by delaying planting. Agropyron rhizomes were heavier in wheat than in barley but those of Agrostis were heavier in barley than in wheat. Agropyron produced most rhizome in thinlysown wheat given nitrogen, but Agrostis most in thinlysown barley without nitrogen. The two treatments had an equal number of rhizomes longer than 100 cm. The agricultural significance of the interaction of the various treatments is briefly discussed. 相似文献
15.
16.
Exotic slugs have become serious pests of canola, at establishment, in Southern Australian high-rainfall cropping zones. Slugs were monitored using relatively inexpensive 300 mm x 300 mm terracotta tiles acting as refuges. An investigation was made of the effects of the time of application of chelated iron baits on the slug species Deroceras reticulatum Müller and Lehmannia nyctelia Bourguignat. Baits reduced the number of surface-active slug species. A single application at sowing provided greater efficacy than one application before sowing, and efficacy was comparable with that of two applications. Canola seedling densities showed a negative response to D. reticulatum numbers; the presence of even one individual per refuge trap reduced seedling numbers below optimum densities. Thistles and other vegetation were associated with increased numbers of slugs. European guidelines for slug monitoring and damage appear to be at least partly applicable to Australian conditions. 相似文献
17.
基于地理信息系统的全国主要粮食作物病虫害实时监测预警系统的研制 总被引：10，自引：1，他引：10
为提高病虫害防治的准确性和科学性，依据植保知识、专家经验，采用人工智能、自行开发的具地理信息系统基本功能及决策支持系统（DSS）的相关技术，研制了基于Internet网络传输的全国主要粮食作物病虫害实时监测预警系统。本系统能够对小麦、玉米、水稻、马铃薯、高粱和谷子6种主要粮食作物的60余种病虫害进行实时监测、预警、诊断、提供植保知识，能够对年度间同期病情、虫情做出图形比较，可将抽象的预警数据转化成清晰简明的点图式电子地图，直观明了地显示病虫害发生点数及地域分布，可根据品种的抗病虫性、病虫害发生基数和未来天气预报等信息对小麦白粉病、赤霉病、纹枯病、稻瘟病、稻曲病、马铃薯晚疫病、麦蚜、小麦吸浆虫和玉米螟9种重要病虫害做出短期防治决策，系统的运行有助于提高人们对主要粮食作物病虫害管理的科学水平。 相似文献
18.
Identification of barley yellow dwarf virus and cereal aphid Infestations In winter wheat by aerial photography 总被引：1，自引：0，他引：1
In 1976 distinctive patterns were identified on aerial photographs of winter wheat crops in East Anglia. The patterns consisted of numerous dark foci which were found to be associated with sooty moulds (mostly Cladosporium spp.) in the crops. Both green and mature crops were photographed in 1977 and the patterns were matched with crop inspection data. These suggested that barley yellow dwarf virus (BYDV) was the cause of the patterns and that sooty moulds secondarily invaded the infected plants. A different type of focal pattern appeared to be associated with damage caused by aphid feeding. All crops showing the pattern associated with BYDV were sown before 13 October but there was no relationship with sowing date for the crops damaged directly by aphids. Yield losses within foci were estimated by sampling and the total crop areas affected were calculated using an image analysis computer: yield losses were estimated to range from 10% (BYDV) to 2% (aphid feeding). The epidemiology of BYDV is discussed and reasons are suggested for the development and appearance of the foci. 相似文献
19.
W. KOCH 《Weed Research》1967,7(1):22-28
Summary. Pot experiments on the competitive effects of charlock (Sinapis arvensis L.) on oats and wild oat (Avena fatua L.) on barley had the following results:
(1) During the period up to tillering there was an appreciable effect of the weeds on crop growth with depression in plant weight of 10–15% from that in the absence of weeds.
(2) The greatest competitive effect occurred up to the middle of shooting of the cereals, when there were depressions in plant weight of 25–32%.
(3) After this stage, the competitive effects of the weeds were much less in pots with a high nutrient level, and at low nutrient level there was almost no competitive effect.
(4) The reduction in growth at the time of weeding was somewhat less at the low nutrient level than at the high nutrient level, and it is concluded that at the high level the competitive ability of the weeds was favoured more than that of the cereal crops.
(5) The cereals were not able to overcome the initial damage caused by the weeds even when the weeds were removed at the beginning of tillering. A partial recovery did how ever occur at the high but not at the low nutrient level.
(6) Both combinations, oats with charlock and barley with wild oat, behaved similarly, but some differences could be observed.
Compétition entre plantes cultivées et mauvaises herbes II. Action des mauvaises herbes annuelles sur les céréales 相似文献
(1) During the period up to tillering there was an appreciable effect of the weeds on crop growth with depression in plant weight of 10–15% from that in the absence of weeds.
(2) The greatest competitive effect occurred up to the middle of shooting of the cereals, when there were depressions in plant weight of 25–32%.
(3) After this stage, the competitive effects of the weeds were much less in pots with a high nutrient level, and at low nutrient level there was almost no competitive effect.
(4) The reduction in growth at the time of weeding was somewhat less at the low nutrient level than at the high nutrient level, and it is concluded that at the high level the competitive ability of the weeds was favoured more than that of the cereal crops.
(5) The cereals were not able to overcome the initial damage caused by the weeds even when the weeds were removed at the beginning of tillering. A partial recovery did how ever occur at the high but not at the low nutrient level.
(6) Both combinations, oats with charlock and barley with wild oat, behaved similarly, but some differences could be observed.
Compétition entre plantes cultivées et mauvaises herbes II. Action des mauvaises herbes annuelles sur les céréales 相似文献
20.
Host plant preference of the Russian wheat aphid Diuraphis noxia (Kurdj.) was studied on 11 cultivars of 9 plant species: winter barley, spring barley, winter wheat, spring wheat, rye, oat, Triticale, canary grass, red millet yellow millet and maize. Seeds of the host plants were sown in a circle near the edge of pots. The host plant choice was evaluated 24 hours after releasing 55 Diuraphis noxia female adults in the middle of each pot. The suitability of different hosts for aphid development was evaluated 2, 7 and 14 days after infestation based on the mean number of Russian wheat aphid individuals per plant. Red millet, yellow millet and maize were chosen by significantly fewer aphids than grain crops. Winter and spring barley were chosen as hosts most frequently, and the progeny production was also the highest on these plants. The growth rate of D. noxia was significantly affected by the host plants and the date of assessment and their interaction. 相似文献