基于MaxEnt模型预测外来入侵植物刺果瓜在中国的潜在地理分布

为明确外来入侵植物刺果瓜 Sicyos angulatus在我国的潜在地理分布,基于MaxEnt模型、ArcGIS软件及全球分布数据,在历史气候条件及未来气候条件下 （低强迫情景SSP126和高强迫情景SSP585）预测刺果瓜在中国的潜在地理分布。结果显示, MaxEnt模型的曲线下面积（area undercurve, AUC）值为0.977,表明模型具有较高的可靠性;气温季节性变化、最热月的最高温、最干月降水量和最湿季节的降水量是影响刺果瓜在中国潜在地理分布的4个关键环境变量;历史气候条件下刺果瓜主要发生在中国东部、中部和西部,适生区总面积占中国陆地总面积的23.29%;未来气候条件下,刺果瓜在中国的适生区范围有所减少, SSP126和SSP585情景下刺果瓜在中国的适生区总面积分别为186.10×10⁴ km²和162.68×10⁴ km²,分别占中国陆地总面积的19.35%和16.91%,但还是主要覆盖黄淮海平原夏播玉米区和南方丘陵玉米区等产区,质心由南向北移动。     

北京首次发现外来入侵植物刺果瓜

刺果瓜原产美国,2010年9月,北京在海淀区温泉镇太舟坞山林地带首次发现,并对生态环境的危害进行了初步调查。本文对该种的形态特征、生物学特性、防控对策等进行了介绍。     

瓜蓟马的发生规律及测报技术初探

瓜蓟马在梧州发生的主要种类有棕榈蓟马(Thrinsnal mi Karng)、蓟马(T·flavas schardk),黄蓟马(T·flavidalas (Bagnall)等,总称瓜蓟马。在梧州年发生十七代左右,世代重叠,第一代是从3月上旬开始,为害冬、节瓜的主害代是二至七代,为害期从4月上旬至5月中旬。冬瓜受害后,顶芽萎缩,生长受抑,幼果伤疤状流汁,茸毛变黑,果     

农抗120的使用技术

农抗120是中国农科院生防室研制的一种新的农用抗生素。在全国植保总站制订的“北方片无公害蔬菜生产规范化措施”中,农抗120列为防治白粉病的首用药剂。 农抗120的产生菌系链霉菌属,刺孢吸水链霉菌的一个变种,定名为刺孢吸水链霉菌北京变种(ftreptomyces hygrospinosus var.beijingesis)。其作用机制是直接阻障病原菌蛋白质的合成,导致病原菌死亡。经多年室内及大面积防治试验表明:农抗12抗菌谱广,防治瓜、果、蔬菜、花卉、烟草、小麦等白粉病;瓜、果、菜发疽病;西瓜、蔬菜枯萎病;水     

外来入侵植物——少花蒺藜草研究进展

少花蒺藜草(Cenchrus pauciflorus Benth.)作为杂草或因为具有入侵性而受到关注,目前在国内传播日趋广泛,发生危害越来越重,为了深入研究其发生规律和防除技术,对其研究现状进行全面的总结十分必要。少花蒺藜草具有倒钩状的刺苞,以带刺的果实进行传播,主要以成熟的刺苞造成危害,在其刺果成熟期,生长区内人畜难行,尤其对羊毛和羊的肠胃伤害特别严重。综述了少花蒺藜草在国内外的分布情况、国内严重发生地区、入侵性及传播途径以及所造成的危害和经济损失等现状。     

刺果瓜甲醇提取物对植物化感作用的研究

为了利用入侵植物资源的化感作用开发植物源除草剂,以刺果瓜的根、茎为试验材料,研究其甲醇提取物(提取率分别是1.85%、1.73%)对苹果芥菜、白菜、谷子、亚麻的芽前、芽后抑制率。芽前试验结果表明:在10 mg/m L浓度下,得到发芽抑制率,苹果芥菜是24.01%、22.22%;白菜是30.80%、19.26%;谷子是20.68%、13.86%;亚麻均为10.00%。可以看出其甲醇提取物对种子萌发有一定影响。芽后试验结果表明:在10 000μg/m L浓度下,得到根长、茎长抑制率,苹果芥菜是38.01%、35.47%,52.69%、74.71%;亚麻是37.65%、35.90%,68.81%、20.14%;白菜是32.61%、36.85%,4.36%、53.34%;谷子是8.23%、10.96%,35.62%、32.12%。可以看出其甲醇提取物对幼苗生长有明显影响。芽前和芽后试验结果表明,刺果瓜根、茎甲醇提取物对苹果芥菜、亚麻、白菜和谷子有一定的抑制活性。     

加强植保监测体系建设，提高病虫监控能力

八步区属南岭山地丘陵地区和典型的亚热带季风气候区,非常适宜各种农作物生长,粮、油、菜、瓜、果等作物面积大,复种指数高。随着种子市场的放开以及气候、耕作栽培、施药防治等因素影响,病虫侵入途径增加,病虫发生形势日趋严峻,水稻常年发生病虫害就有30多种,水稻“两迁”害虫（稻飞虱、稻纵卷叶螟）、螟类、稻瘟病、纹枯病等频繁发生,2010年又发生罕见的南方水稻黑条矮缩病;     

天达2116应用技术

（接第3期）对于瓜茄果类型的蔬菜使用天达—2116可以早结瓜（果）、多结瓜（果）、结好瓜（果），对温度、湿度等不良环境条件产生的生理病害以及药害、肥害都有缓解、抑制和修复作用，增产幅度在20％以上，节省农药在30％以上．提高耐储性和商品价值，商品率提高15％以上，综合效益显著。对于地下根茎类型的蔬菜使用天达2116．可以促进茎叶生长，提高光合作用，促进养分输送和积累．抑制先期抽薹，加速地下害虫咬伤后的修复．克服生理失调．增产幅度在30％以上．商品率和耐储性都有明显提高。     

西瓜细菌性果斑病调查初报

西瓜细菌性果斑病是近几年在霞浦县西瓜上发生的1种新病害。具有发病快、防治难、为害重等特点。因其致病的特殊性和某些客观因素限制,几年来,该病的发生难以控制,对本县西瓜生产已构成严重威胁。笔者将近年来田间调查情况报道如下:1发病情况西瓜细菌性果斑病于2002年6月在本县盐田、沙江、洲洋3个乡(镇)首次发现,发生面积约12hm2。近年来迅速扩展到长春、崇儒、柏洋、牙城等7个主产西瓜的乡(镇),年发生面积120～200hm2,染病瓜地西瓜产量损失30%～100%,造成毁灭性为害。2病害症状幼苗子叶发病,叶背面呈现水渍状斑点,并沿主脉逐渐发展为黑褐…     

永寿旱塬果区草履蚧发生为害特点与综合防治

永寿县地处陕西省渭北旱塬西部的南缘地带,近几年来草履蚧[Drosichacorpulenta(kuwana)]在本县局部果区发生逐年加重。草履蚧又名草履硕蚧、日本草履蚧。以其若虫和雌成虫刺吸苹果、桃等果树的嫩芽、枝干汁液,造成树势衰弱,生长不良,严重时可使枝、梢、芽枯萎,甚至整株死亡。19     

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.     

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.     

Effect of botanical insecticides and bacterial toxins on the gut enzyme of the rice leaffolderCnaphalocrocis medinalis

The effect of botanical insecticides and bacterial toxins on gut enzyme activity of larvae of the rice leaffolderCnaphalocrocis medinalis (Guenée) (Insecta: Lepidoptera: Pyralidae) was investigated. Gut enzyme activities were affected by botanical insecticides and bacterial toxin individually and in combination. When fed a diet of rice leaves treated with botanical insecticides and bacterial toxins, in bioassays the activities of gut tissue enzymes — acid phosphatases (ACP), alkaline phosphatases (ALP) and adenosine triphosphatases (ATPase) — of rice leaffolder larvae were affected. When combined, the effect was more severe at a low concentration. Larvae that were chronically exposed to botanical insecticides and bacterial toxins showed a reduction in weight (59–89%) and exhibited a significant reduction in ACP, ALP and ATPase activities. The combination ofBacillus thuringiensis kurstaki and botanical insecticides caused a decrease of twofold in enzyme activity even at reduced concentration. A synergistic effect was found when botanical insecticides and bacterial toxins were combined at low doses. These effects were most pronounced in early instars. Clear dose-response relationships were established with respect to enzyme activity. In conclusion: (i) biopesticides are relatively safe and biodegradable; (ii) a synergistic effect of botanical insecticides and bacterial toxins was found; (iii) less expensive, readily available and naturally occurring biopesticides could be an alternative for organic and inorganic pesticides in controlling RLF. http://www.phytoparasitica.org posting Sept. 28, 2004.