不同杀菌剂对小麦赤霉病和叶锈病的防治效果

为明确不同杀菌剂防治小麦赤霉病和叶锈病的效果,在大田条件下进行了不同杀菌剂对这两种病害的防治试验。对小麦赤霉病的防效结果表明:25%氰烯菌酯SC、20%叶菌唑SC、48%氰烯·戊唑醇SC和200 g/L氟唑菌酰羟胺SC的防效较好,防效为83.54%~88.92%;其次为400 g/L戊唑·咪鲜胺EW和430 g/L戊唑醇SC,防效为71.87%和73.31%;50%多菌灵WP的防效仅为58.05%。对小麦叶锈病的防效调查结果表明:30%丙硫菌唑SC、40%丙硫·戊唑醇SC和430 g/L戊唑醇SC的防效较好,防效为84.78%~88.33%;其次275 g/L氟唑菌酰羟胺·丙环唑SE、48%氰烯·戊唑醇SC、40%叶菌·戊唑醇SC和400 g/L戊唑·咪鲜胺EW,防效范围为79.66%~81.56%;200 g/L氟唑菌酰羟胺SC和50%多菌灵WP的防效为69.36%和39.33%。从防治效果、两种病害兼防以及延缓抗药性等方面综合考虑,氰烯·戊唑醇、氟唑菌酰羟胺·丙环唑、丙硫·戊唑醇、叶菌·戊唑醇等交替使用是防治小麦赤霉病和叶锈病比较好的策略。     

不同药剂处理对小麦赤霉病的田间防治效果

为筛选出防治小麦赤霉病高效药剂以便更好地服务于农业生产,本试验采用200 g/L氟唑菌酰羟胺悬浮剂+250 g/L丙环唑乳油、40%丙硫菌唑·戊唑醇悬浮剂、480 g/L氰烯·戊唑醇悬浮剂、30%肟菌·戊唑醇悬浮剂、40%唑醚·戊唑醇悬浮剂、44%戊唑·咪鲜胺水乳剂共6种药剂处理对小麦赤霉病进行田间防治试验。结果表明,200 g/L氟唑菌酰羟胺悬浮剂975 mL/hm²+250 g/L丙环唑乳油600 mL/hm²处理和40%丙硫菌唑·戊唑醇悬浮剂750 mL/hm²处理的防效和增产效果相当,且均优于其它药剂处理,值得在生产中推广应用。     

不同杀菌剂对小麦赤霉病及籽粒DON毒素的控制效果

为探明不同杀菌剂对小麦赤霉病和小麦籽粒DON毒素(包括DON、3-ADON和15-ADON)的控制效果, 采用菌丝生长速率法测定了12种药剂对禾谷镰刀菌野生型菌株PH-1的室内活性, 同时采用液相色谱-串联质谱法(LC-MS)测定了这些药剂对DON毒素的抑制效果, 并开展了小麦赤霉病及籽粒DON毒素的田间防治试验。结果表明, 12种原药对菌丝生长抑制活性强弱依次为氟唑菌酰羟胺>咪鲜胺>戊唑醇>丙硫菌唑>叶菌唑>氰烯菌酯>氟环唑>多菌灵>甲基硫菌灵>吡唑醚菌酯>嘧菌酯>井冈霉素A。氟环唑EC50和EC90离体胁迫均刺激DON毒素产生, 其他杀菌剂EC50和EC90胁迫均抑制DON毒素产生。田间试验结果表明, 200 g/L氟唑菌酰羟胺SC、30%丙硫菌唑OD和20%叶菌唑WP病指防效和DON防效为87.68%~94.77%; 430 g/L戊唑醇SC、25%氰烯菌酯SC、45%咪鲜胺EW、25%氟环唑SC、50%多菌灵WP和70%甲基硫菌灵WP病指防效和DON防效为57.63%%~85.49%; 250 g/L吡唑醚菌酯EC和250 g/L嘧菌酯SC病指防效分别为72.18%和51.98%, DON防效分别为43.06%和-7.96%; 24%井冈霉素A AS病指防效和DON防效分别为42.37%和62.87%。药剂离体和田间控毒效果不完全一致, 赤霉病有效防控是DON防控的前提, 病害防效与DON防效不完全一致, 本研究为小麦赤霉病及籽粒DON毒素防控提供了科学依据。     

5种不同药剂防治小麦赤霉病田间药效试验

作者开展了40%咪铜·氟环唑SC等5种杀菌剂对小麦赤霉病的田间防效试验。结果表明,80%戊唑醇WG、80%多菌灵WP、40%咪铜·氟环唑SC、15%丙唑·戊唑醇SC和325g/L苯甲·嘧菌酯SC对小麦赤霉病的防效分别达到73.15%、60.07%、83.56%、71.81%和56.38,以40%咪铜·氟环唑SC防治效果最好。     

不同药剂对小麦赤霉病的防治效果

进行不同药剂防治小麦赤霉病的田间药效试验的结果表明:250g/L嘧菌酯SC、325g/L嘧菌酯·苯醚SC、250g/L嘧菌酯SC+43%戊唑醇SC、43%戊唑醇SC、25%氰烯菌酯SC、30%嘧菌酯·咪鲜胺ME、25%咪鲜胺EC、42%咪鲜·甲硫灵WP对小麦赤霉病防效63.29%~79.1%,较CK增产18.6%~32.7%,赤霉病防效和增产效果均优于30%己唑醇SC、40%多·酮WP。小麦赤霉病适时预防是关键,在小麦齐穗至扬花达5%时施第一次药,间隔7d~10d施第二次药,药剂要交替轮换使用。     

4种杀菌剂对小麦赤霉病的防治效果

为明确30％丙硫菌唑可分散油悬浮剂、430g/L戊唑醇悬浮剂、24％戊唑·咪鲜胺可湿性粉剂、15％丙唑·戊唑醇悬浮剂对小麦赤霉病的防治效果及对小麦产量的影响,分别于2020、2021年进行大田试验.结果表明:2020年和2021年,供试杀菌剂对小麦赤霉病的田间防效分别为82.88％～97.37％和78.14％～93.2...     

4种复配制剂对小麦赤霉病的田间防效

小麦赤霉病在河南唐河呈逐年加重趋势,严重影响小麦生产,并对当地常规防治药剂产生了抗性。为了筛选出防治该病效果较好的替代药剂,以常规药剂多菌灵单剂为对照,选择了4种新型复配制剂对当地小麦赤霉病进行田间防效试验。结果发现,在两次施药后,30%戊唑醇·福美双悬浮剂90 mL/667m~2、48%氰烯菌酯·戊唑醇悬浮剂50 mL/667m~2、20%氰烯菌酯·己唑醇悬浮剂100 mL/667m~2、45%戊唑醇·咪鲜胺可湿性粉剂35 g/667m~2 4个处理对小麦赤霉病的病指防效均在70%以上,显著高于对照药剂。其中,以48%氰烯菌酯·戊唑醇悬浮剂处理的防效最高,达80.2%;4个复配剂处理区的小麦较清水对照区增产率也均在30%以上,增产效果也明显优于多菌灵。     

多菌灵及其复配制剂防治小麦赤霉病的应用效果

为测定在小麦赤霉病菌Fusarium graminearum抗性频率上升的条件下多菌灵及其复配制剂对小麦赤霉病的防效,于2014—2016年监测了江苏省南通市同块试验田中小麦赤霉病菌对多菌灵的抗药性,并进行了田间药效试验。结果表明,2014、2015和2016年小麦赤霉病菌对多菌灵的抗性频率分别为22.97%、38.55%和43.38%,呈逐年上升趋势。2016年戊唑醇及复配剂多菌灵·戊唑醇、多菌灵·三唑酮处理对小麦赤霉病的田间防效分别达97.82%、92.16%、85.98%,增产效果分别达23.90%、23.54%、22.57%;小麦样品(混粒)中DON毒素含量分别比空白对照降低57.39%、59.99%、43.34%,均优于多菌灵单剂处理,其中以戊唑醇及复配剂多菌灵·戊唑醇处理最好,多菌灵·三唑酮处理次之。因此,在抗性程度中等或偏轻的地区,采用戊唑醇、复配剂多菌灵·戊唑醇防治小麦赤霉病可取得较好的防病、增产及降低DON毒素的效果。     

复配杀菌剂防治小麦赤霉病田间药效

2016年研究了3种复配杀菌剂对小麦赤霉病的田间防治效果。结果表明,以有效成分用量35%丙环唑·多菌灵悬乳剂630~840 g/hm~2处理的田间防效85.28%~88.83%,30%多菌灵·戊唑醇悬浮剂180~225 g/hm~2处理田间防效86.74%~92.36%,30%多菌灵·氟环唑悬浮剂450~540 g/hm~2处理田间防效85.61%~90.28%,3种复配剂对小麦赤霉病的田间防治效果均优于相应单剂,且显著高于常规杀菌剂多菌灵。     

戊唑·咪鲜胺防治小麦赤霉病试验效果

为检验45%戊唑·咪鲜胺水乳剂防治小麦赤霉病的效果,以当地常用的防治药剂作为对照,进行了田间防治试验。在2014年安徽庐江试验区小麦赤霉病流行较重的情况下,于小麦初花期施第1次药,7 d后施第2次药,至小麦赤霉病病情稳定时调查。45%戊唑·咪鲜胺水乳剂不同用量处理的病穗防效达65.49%~91.45%,病指防效达70.38%~92.66%。其中,600、750 mL/hm~2处理的防效均高于对照药剂36%多·酮悬浮剂2 250 mL/hm~2处理和20%烯肟·戊唑醇悬浮剂600mL/hm~2处理。45%戊唑·咪鲜胺水乳剂处理的增产效果明显,增产率达27.83%~35.94%,高于对照药剂。     

Hymenopteran Parasitoids on Fruit-infesting Tephritidae (Diptera) in Latin America and the Southern United States: Diversity, Distribution, Taxonomic Status and their use in Fruit Fly Biological Control

We first discuss the diversity of fruit fly (Diptera: Tephritidae) parasitoids (Hymenoptera) of the Neotropics. Even though the emphasis is on Anastrepha parasitoids, we also review all the information available on parasitoids attacking flies in the genera Ceratitis, Rhagoletis, Rhagoletotrypeta, Toxotrypana and Zonosemata. We center our analysis in parasitoid guilds, parasitoid assemblage size and fly host profiles. We also discuss distribution patterns and the taxonomic status of all known Anastrepha parasitoids. We follow by providing a historical overview of biological control of pestiferous tephritids in Latin American and Florida (U.S.A.) and by analyzing the success or failure of classical and augmentative biological control programs implemented to date in these regions. We also discuss the lack of success of introductions of exotic fruit fly parasitoids in various Latin American countries. We finish by discussing the most pressing needs related to fruit fly biological control (classical, augmentative, and conservation modalities) in areas of the Neotropics where fruit fly populations severely restrict the development of commercial fruit growing. We also address the need for much more intensive research on the bioecology of native fruit fly parasitoids.     

Brief Guide for Authors

正Journal of Arid Land(JAL)is an international journal(ISSN 1674-6767;CN 65-1278/K)for the natural sciences,sponsored by the Xinjiang Institute of Ecology and Geography,Chinese Academy of Sciences and Science Press.It is published by Science Press and Springer-Verlag Berlin Heidelberg bimonthly.JAL publishes original,innovative,and integrative research from arid and semiarid regions,ad     

The parasitoid complex ofLiriomyza cicerina on chickpea (Cicer arietinum)

Liriomyza cicerina (Diptera: Agromyzidae) is an important pest on chickpea in Turkey. The objective of this study was to determine the parasitoids and rates of parasitism ofL. cicerina on chickpea (Cicer arietinum L.) during the 2005 and 2006 seasons in ?anl?urfa province, Turkey. Leaves with mines were sampled weekly and kept in the laboratory to observe and count emerging leafminer and parasitoid adults. Eight parasitoid species were collected: the braconidsOpius monilicornis Fischer andOpius tersus Foerster and the eulophidsDiaulinopsis arenaria (Erdös) andNeochrysocharis formosa (Westwood), which occurred in both the winter and summer seasons;Diglyphus crassinervis Erdös,Neochrysocharis ambitiosa Hansson,Neochrysocharis sericea (Erdös) andPediobius metallicus (Nees), which occurred only in the summer growing areas.Diaulinopsis arenaria was the predominant parasitoid with 4–7.7% parasitism rate whileN. ambitiosa andO. monilicornis were the second and third most predominant species. The results of these trials show that sinceDia. arenaria occurred throughout every season, it could potentially be used for control of the leafminerL. cicerina.     

Plant–herbivore asynchrony necessitates augmentative releases of the exotic beetle,Zygogramma bicolorata,to enhance the biological control of P arthenium hysterophorus

Systematic information on the quantitative impact of Z ygogramma bicolorata on the biology of P arthenium hysterophorus is crucial as the seeds of this weed continue to germinate from the accumulated soil seed bank throughout the year in the form of different germinating flushes, while the activity of the beetle ceases during winter as it enters diapause. Therefore, plant–herbivore interactions need to be explored to develop predictions of the overall impact of the introduced beetle on the weed. The findings revealed that defoliation by Z . bicolorata had a significant impact on the plant height, density and flower production in flushes F ₃, F ₄ and F ₅, but not in F ₁ and F ₂ that exhibited longer periodicity, profuse branching, a longer flowering period and maximum flower production and contributed mostly to the existing seed soil bank. Therefore, total depletion of the existing soil seed bank was not possible. Consequently, the effect of augmentative field releases of laboratory‐reared beetles was explored on F ₁ and F ₂ in February for three consecutive years (2011–2013). Before initiating the trial, random soil samples were taken from the plots that were assigned to the paired treatments (i.e. with the beetle and without the beetle [insecticide‐treated]) and it was found that the seed bank in those samples did not differ. The single release of Z . bicolorata adults at five per plant at the six‐leaf stage significantly reduced the soil seed bank, compared to without the biocontrol agent, irrespective of the flushes at the end of the season.     

Richtlinien der Verbände des ökologischen Landbaus zum Vorratsschutz

Zusammenfassung Verbände des ökologischen Landbaus wie z. B. Bioland, Gäa, Demeter; Naturland, Ernte für das Leben oder Bio Suisse beschränken ihre Mitglieder bei der Wahl von Vorratsschutzmaßnahmen. Vorrang besitzen Maßnahmen zur Vermeidung von Schädlingen gegenüber Bekämpfungsmaßnahmen. Fallen müssen zur Befallsüberwachung eingesetzt werden, um einen Befall durch Vorratsschädlinge frühzeitig zu erkennen. Diese Maßnahmen sollen den weitgehenden Verzicht auf chemisch-synthetische Mittel ermöglichen. In diesem Beitrag werden die Empfehlungen der Verbände mit den derzeit verfügbaren chemischen Mitteln für den Vorratsschutz abgeglichen. Erfahrung in der praktischen Umsetzung von physikalischen und biologischen Verfahren werden diskutiert und Defizite bei der Befallsüberwachung und Bekämpfung beschrieben.     

Development of protocols for detection of Colletotrichum acutatum and monitoring of strawberry anthracnose using real-time PCR

Real-time PCR (TaqMan®) assays were developed for the specific detection and discrimination of Colletotrichum spp., C. acutatum and C. gloeosporioides causing anthracnose in strawberry using the most divergent area of the internal transcribed spacers (ITS1 and ITS2) and 5·8S ribosomal RNA (rRNA) gene region. The specificity of the new assays was tested using DNA from six species of Colletotrichum and nine fungal species commonly found associated with strawberry material, and additionally by comparing the sequences with those from databases using a blast search. The sequences only showed identity with homologous sequences from the desired target organisms. The new assays were 10–100 times more sensitive than conventional PCR methods previously published for the diagnosis of strawberry anthracnose. When real-time PCR was compared with ELISA methods, PCR improved the sensitivity of the identification by obtaining positive results for samples of strawberry plant material that tested negative with ELISA. The development of C. acutatum was monitored using artificially infected strawberry crowns from two strawberry cultivars (Camarosa and Ventana) and a real-time PCR assay specific for this species between January and June 2006. The amount of C. acutatum detected using real-time PCR varied significantly by month ( P  < 0·001), but not by cultivar ( P  = 0·394). The new assays were shown to be useful tools for rapid detection and identification of these pathogens and to allow rapid and accurate assessment of the casual agents of anthracnose in strawberry.     

Effects of the saprophytic leaf mycoflora on growth and productivity of winter wheat

The effects of the saprophytic mycoflora and its interference with cereal aphids on growth and yield of winter and spring wheat was studied in field experiments in 1980, 1981 and 1982.Yields varied between 5000 and 8000 kg dry matter of kernels per ha. The effect of the saprophytic mycoflora on yield was determined in different treatments: A) no control measures against cereal aphids and saprophytic and necrotrophic fungi, B) no control of cereal aphids, control of saprophytic and necrotrophic fungi, C) control of cereal aphids and control of saprophytic and necrotrophic fungi, D) control of cereal aphids and stimulation of saprophytic mycoflora and E) control of cereal aphids, no control of saprophytic and necrotrophic fungi nor stimulation of saprophytic mycoflora.Considerable differences in top densities of saprophytic mycoflora (10 times as large in A and D as in B and C) were determined. The consequences of these differences for the growth and productivity of wheat were minor. A negative effect of saprophytic mycoflora on the yield could not be detected in 1981 and 1982, whereas a small positive significant effect was found in 1980. This stimulation may have been due to competition between necrotrophic fungal pathogens and saprophytic mycoflora. As a result of favourable weather conditions necrotrophic fungal pathogens were very numerous in 1980 and could form an important yield reducing factor. Yield levels may effect the importance of the necrotrophic and saprophytic mycoflora as yield reducing factors. Additionally, in the presence of aphid honeydew captafol was found to be relatively ineffective against saprophytic fungi.     

Relationship Between Production of the Phytotoxin Prehelminthosporol and Virulence in Isolates of the Plant Pathogenic Fungus Bipolaris sorokiniana

A gas chromatographic method was developed to quantify the phytotoxin prehelminthosporol, which is a sesquiterpene metabolite of the plant pathogen Bipolaris sorokiniana. The toxin was extracted from mycelium or culture filtrates, pre-cleaned using solid phase extraction, and analyzed by gas chromatography as a trimethylsilyl-derivative. The detection limit of the method was 5ngl^–1 (signal to noise ratio 4:1) which corresponds to ca. 15ng prehelminthosporol per mg dry weight of mycelium or 15ng prehelminthosporol per ml culture filtrate. The total amount of prehelminthosporol (mycelium plus culture filtrate) increased with cultivation time when examined in six isolates of B. sorokiniana after 6, 9, 12 and 15 days of incubation. The screening experiment of 17 isolates for prehelminthosporol production after 8 days of incubation revealed significant differences in the toxin production between the isolates. The isolates with low toxin production had lower virulence towards barley roots compared to those with higher production of the toxin. However, the virulence did not increase with prehelminthosporol level among the high producing isolates. Prehelminthosporol was also analyzed in a number of related Bipolaris and Drechslera species. In addition to B. sorokiniana, three out of six Bipolaris species (B. setariae, B. zeicola, B. victoriae) produced prehelminthosporol, which indicates that ability to produce prehelminthosporol is conserved among closely-related Bipolaris species.