深圳市蚂蚁区系与分类研究(膜翅目:蚁科)

为揭示深圳市的蚂蚁区系特点,采用样地调查法在其6个行政区海拔3～944 m范围11类生境9种植被类型中采集蚂蚁标本32 255头。经分类鉴定,有4亚科,18属,35种,发现14个广东省新记录种,暗首姬猛蚁(Hypoponera opaciceps(Mayr))为中国大陆新记录种。列出了物种名录和地理分布,分析了蚂蚁物种的分布类型和区系成分。深圳市的蚂蚁区系具有典型的东洋界特征,具有入侵能力的物种有13个。红火蚁(Solenopsis invicta Buren)是最危险的入侵物种,其繁殖和扩散能力强,防治难度大,在未来的预防和防治工作中应当高度重视。     

Impact of the red imported fire ant Solenopsis invicta Buren on biodiversity in South China: A review

The red imported fire ant, Solenopsis invicta, is a problematic invasive species in China since at least 2003. Over the past 15 years, a numerous studies were published on the impacts of this species on flora, fauna, and ecosystem function in natural and agricultural systems. We reviewed the literature on S. invicta invasion biology and impacts on biodiversity in South China. Both monogyne and polygyne colonies of S. invicta were introduced to China and polygyne colony is the dominant type. The range expansion rate of S. invicta may reach 26.5–48.1 km yr–1 in China. S. invicta forage activities occur year-round, peaking in the summer and fall in South China and show a preference for insects and plant seeds. We describe the ecological impacts of S. invicta on various habitats in South China, including arthropod community structure disruption and decreases in diversity and abundance of native ant species. S. invicta can replace the role of native ants in mutualisms between ants and honeydew-producing Hemiptera, which results in loss of important food resources for native ants and natural enemies of hemipterans. Further research is required to assess the complex ecosystem-level impacts of S. invicta in introduced areas.     

广西3种新记录外来入侵植物

报道了采自防城港市的3种广西新记录外来入侵植物. 它们是紫斑大戟 Euphorbia hyssopifolia L.、翼茎阔苞菊 Pluchea sagittalis (Lam. ) Cabrera和丝毛雀稗 Paspalum urvillei Steud.. 标本存放于华南农业大学林学院植物标本室 (CANT).     

First report of the South American tomato leafminer,Tuta absoluta (Meyrick), in China

Tuta absoluta (Meyrick) originated in South America and is one of the most serious pests of tomatoes. It is also known to attack other solanaceous crops, including potato, eggplant, pepper, tobacco, and weedy species such as black nightshade. After accidental introduction into Spain in 2006, this pest spread rapidly throughout Afro-Eurasia and has become a major threat to tomato production worldwide. Here, we report the first record of T. absoluta as an invasive pest in China. It was found in tomato fields in Ili Kazakg Autonomous Prefecture, Xinjiang Uygur Autonomous Region (Ili, Xinjiang), China, and its occurrence was confirmed by both morphological and molecular approaches. In Ili, T. absoluta has been found to attack eggplant, potato, and black nightshade. We found the larvae generally mining and feeding on leaves and boring into tomato fruits, with multiple larvae sometimes observed in a single fruit. Its infestation levels differ among the tomato fields and host species. In all of the surveyed tomato fields, T. absoluta infested 100% of plants. In some of the fields, up to 90% of the eggplant and 100% of the potato plants were infested. Since no natural enemies were found under field conditions, suitable management practices are urgently needed to stop the further spread of this destructive pest in China.     

海南省蝶形花科3种新记录外来入侵植物

报道了海南省3种新记录外来入侵植物.它们是紫花大翼豆Macroptilum atropurpureum(DC.)Urban、大翼豆M.lathroides(L.)Urban和南美山蚂蝗Desmodium tortuosum(Sw.)DC..标本存放于华南农业大学林学院植物标本室(CANT).     

外来物种红火蚁入侵生物学与防控研究进展

截至2019年,我国大陆发现红火蚁Solenopsis invictaBuren发生危害已经15年了。在有关部门/机构的支持下,围绕着种群控制理论和技术,华南农业大学红火蚁研究中心坚持开展红火蚁相关基础研究和防控应用工作。本文系统总结了我国大陆红火蚁入侵、传播和扩张的时空规律,阐明了红火蚁暴发灾变的生物学基础和规律以及入侵对农业生态系统的影响,明确了其入侵优势和生态学效应,阐释了红火蚁的化学防治理论基础;介绍了监测技术体系、检疫除害技术体系和应急防控、根除与治理技术体系的创建,以及推广应用。研究成果可为我国红火蚁的防治提供重要科技支撑与保障。     

EalspF1, Essential Enzyme in Isoprenoid Biosynthesis from Eupatorium adenophorum,Reveals a Novel Role in Light Acclimation

Isoprenoids are a functionally and structurally diverse class of natural organic chemicals. The universal precursors of all isoprenoids, isopentenyl diphosphate and dimethylallyl diphosphate are synthesized through the mevalonate and 2C-methyl-D-erythritol 4-phosphate (MEP) pathways, respectively. Many isoprenoids produced through the MEP pathway play an important role in plant acclimation to different light environments. Eupatorium adenophorum, an invasive weed in China, presents a remarkable capacity to acclimate to various light environments, which constitutes its solid foundation of being a successful invasive species. Thus we aimed at gaining a deeper insight into the regulation of MEP pathway in E. adenophorum to further understand the invasive mechanism. 2C-Methyl-D-erythritol 2,4-cyclodiphosphate synthase (IspF or MCS) is an essential enzyme in the MEP pathway. In this paper, a novel IspF gene was cloned and characterized from E. adenophorum. Tissue-specific expression assays revealed a higher expression of EaIspF1 in leaves than in stems and roots. The expression of EaIspF1 was responsive to different light conditions. Some up-regulation of EaIspF1 expression was also found after the treatments with signal compounds and after wounding stress. Interestingly, the over-expression of EaIspF1 in Arabidopsis led to increase carotenoids contents, resulting in an enhanced tolerance to high light. Taken together, these results indicate that the EaIspF1-derived enzyme participates in isoprenoid metabolism and among others, the expression of this gene in E. adenophorum is involved in the regulation of plastidial isoprenoids, which play an important role in acclimation to various light environments.     

New geographic distribution and molecular diversity of Citrus chlorotic dwarf-associated virus in China

In 2009, an emerging citrus viral disease caused by Citrus chlorotic dwarf-associated virus (CCDaV) was discovered in Yunnan Province of China. However, the occurrence and spread of CCDaV in other citrus-growing provinces in China is unknown to date. To better understand the distribution and molecular diversity of CCDaV in China, a total of 1 772 citrus samples were collected from 11 major citrus-growing provinces and were tested for CCDaV by PCR. Among these, 134 citrus samples from Guangxi, Yunnan and Guangdong were tested positive for CCDaV, demonstrating that the occurrence and spread of CCDaV are increasing in China. The complete genome sequences of 17 CCDaV isolates from different provinces and hosts were sequenced. Comparisons of the whole-genome sequences of the 17 CCDaV isolates as well as the 15 isolates available in GenBank revealed that the sequence identity was about 99–100%, showing that the CCDaV isolates were highly conserved. Phylogenetic studies showed that the 32 CCDaV isolates belonged to four different groups based on geographical origins and host species, and that CCDaV isolates from China and Turkey were clustered into different groups. The results provide important information for clarifying the distribution and genetic diversity of CCDaV in China.     

入侵害虫红火蚁在中国的适生性分布研究

【目的】对红火蚁在中国大陆地区可能适生分布的地区进行分析和预测。【方法】运用CLIMEX气候模型的气候相似系数法和地点比较法以及地理信息系统（ArcGIS8.3）对该虫在中国的适生区进行分析和预测。【结果与结论】CLIMEX预测入侵红火蚁可以在中国大陆19省区的47个市、县（地区）生存，其中在温湿度较高、降雨量较多的华南地区最适宜生存；结合GIS的预测，该虫在中国的适生范围为16.32°N～41.33°N，91.46°E～122.01°E。     

Molecular characteristics and temperature tolerance function of the transient receptor potential in the native Bemisia tabaci AsiaII3 cryptic species

Insects are poikilothermic animals, and temperature is one of the most important abiotic factors affecting their spread and distribution. For example, differences in thermal tolerance may underlie the significant differences in geographical distributions between the native AsiaII3 and invasive MED (Mediterranean) cryptic Bemisia tabaci species in China. Transient receptor potential (TRP) channels are key components of the insect temperature perception system and act as molecular thermometers since they can be activated by specific changes in temperature. In this study, we cloned and characterized the AsiaII3 BtTRP gene and revealed its functions in the response to thermal stress. The full-length cDNA of BtTRP was 3821 bp, with a 3501-bp open reading frame encoding a 132.05-kDa protein. Comparing the deduced amino acid sequences of AsiaII3 BtTRP and MED TRP revealed five amino acid differences. In situ hybridization indicated that BtTRP might be widely expressed throughout the AsiaII3 adult body. BtTRP mRNA expression reached the highest levels after exposure to mild thermal stimuli (12 and 35°C), showing that BtTRP expression can be induced by temperature stress. Furthermore, the thermal tolerance of AsiaII3 after BtTRP dsRNA feeding was significantly lower than that of the control. Taken together, the present study highlights the importance of TRP channels for B. tabaci thermal resistance, and allows us to infer that the differences in amino acids between AsiaII3 and MED might cause the differences in thermal tolerance of these two cryptic species. This study provides a new direction for investigating geographic distribution differences between invasive and native insects.     

Detection of arboviruses in Culicoides(Diptera: Ceratopogonidae) collected from animal farms in the border areas of Yunnan Province,China

Biting midges of the genus Culicoides(order Diptera, family Ceratopogonidae) are potential biological vectors for the transmission of certain arboviruses among humans, livestock, and wild animals. This study collected a total of 405 Culicoides individuals from seven animal farms located in five counties in the border areas of Yunnan Province, China, and examined the Culicoides species composition and the major arboviruses carried by the Culicoides species. The collected Culicoides were classified into seven species with variable abundances: Culicoides arakawae(5.43%, 22/405), Culicoides homotomus(1.23%, 5/405), Culicoides obsoletus(19.75%, 80/405), Culicoides orientalis(17.28%, 70/405), Culicoides oxystoma(29.38%, 119/405), Culicoides peregrinus(5.68%, 23/405), and Culicoides nipponensis(21.23%, 86/405). Among the seven species, C. oxystoma and C. nipponensis were distributed in all the five counties with abundances of 13.33–44.87% and 10.00–46.83%, respectively, suggesting that these were the dominant species of Culicoides widespread on animal farms in the border areas. PCR was used to detect major arboviruses in the collected Culicoides specimens, including bluetongue virus(BTV), Japanese encephalitis virus, Dengue virus, Zika virus, African swine fever virus, and African horse sickness virus. Among the tested viruses, only BTV serotype 1 was tested positive in C. oxystoma specimens collected from a buffalo farm. Culicoides oxystoma was the dominant species on animal farms in the sampled areas, but it has not previously been documented as positive for BTV in China. The current results thus suggest that C. oxystoma could be an important vector for BTV transmission in these border areas, which, however, needs to be confirmed by further comprehensive experiments. Overall, the present study provides the first profile of Culicoides species on animal farms in the China, Vietnam, and Myanmar border areas, establishes the prevalence of arboviruses carried by these Culicoides species, and suggests the vector potential of C. oxystoma species for the transmission of BTV.     

Range expansion of the invasive cotton mealybug,Phenacoccus solenopsis Tinsley: An increasing threat to agricultural and horticultural crops in China

The globally invasive cotton mealybug Phenacoccus solenopsis Tinsley, has recently invaded several Chinese regions, and continues to expand its range. This mealybug is a polyphagous insect pest, with at least 200 host plants from 63 families, including cotton, food crops, fruits, ornamental plants, tobacco, and vegetables. Here, we describe the first finding of P. solenopsis in Shandong Province, and investigate the abundances of its natural enemies (predator Coccinella septempunctata L. and parasitoid Aenasius bambawalei Hayat). All three species were detected from ornamental and weed species in Linyi, Shandong, in September 2018, and were positively identified using DNA barcoding. BLAST analysis revealed significant identity (99.38–100%) between sequences of P. solenopsis obtained in this study and those published in the past. This invasive pest represents a major potential threat to agri-horticulture in Shandong, which is a key province of China for production and export of many vegetables, flowers, fruits, and other crops. This mealybug species has a wide range of potential distribution in Shandong and is easily dispersed with agricultural and horticultural transport products. Further monitoring and management strategies are required to limit the spread of this pest species.     

Toxicity and horizontal transfer of bifenthrin and dimefluthrin against the red imported fire ant,Solenopsis invicta Buren (Hymenoptera: Formicidae), and the efficacy of their dust applications in the field

The red imported fire ant, Solenopsis invicta Buren, poses a significant threat to biodiversity, agriculture, and public health in its introduced ranges. While chemicals such as toxic baits and dust are the main methods for S. invicta control, toxic baits are slow, requiring approximately one or two weeks, but dust can eliminate the colony of fire ants rapidly in just three to five days. To explore more active ingredients for fire ant control using dusts, the toxicity of bifenthrin and dimefluthrin, the horizontal transfer of bifenthrin and dimefluthrin dust and their efficacy in the field were tested. The results showed that the LD₅₀ (lethal dose) values of bifenthrin and dimefluthrin were 3.40 and 1.57 ng/ant, respectively. The KT₅₀ (median knockdown time) and KT₉₅ (95% knockdown time) values of a 20 μg mL^–1 bifenthrin dose were 7.179 and 16.611 min, respectively. The KT₅₀ and KT₉₅ of a 5 μg mL^–1 dimefluthrin dose were 1.538 and 2.825 min, respectively. The horizontal transfers of bifenthrin and dimefluthrin among workers were effective. The mortality of recipients (secondary mortality) and secondary recipients (tertiary mortality) were both over 80% at 48 h after 0.25, 0.50 and 1.00% bifenthrin dust treatments. The secondary mortality of recipients was over 99% at 48 h after 0.25, 0.50 and 1.00% dimefluthrin dust treatments, but the tertiary mortality was below 20%. The field trial results showed that both bifenthrin and dimefluthrin exhibited excellent fire ant control effects, and the comprehensive control effects of 1.00% bifenthrin and dimefluthrin dusts at 14 d post-treatment were 95.87 and 85.70%, respectively.     

Yield and water use responses of winter wheat to irrigation and nitrogen application in the North China Plain

With increasing water shortage resources and extravagant nitrogen application, there is an urgent need to optimize irrigation regimes and nitrogen management for winter wheat(Triticum aestivum L.) in the North China Plain(NCP). A 4-year field experiment was conducted to evaluate the effect of three irrigation levels(W1, irrigation once at jointing stage; W2, irrigation once at jointing and once at heading stage; W3, irrigation once at jointing, once at heading, and once at filling stage; 60 mm each irrigation) and four N fertilizer rates(N0, 0; N1, 100 kg N ha~(-1); N2, 200 kg N ha~(-1); N3, 300 kg N ha~(-1)) on wheat yield, water use efficiency, fertilizer agronomic efficiency, and economic benefits. The results showed that wheat yield under W2 condition was similar to that under W3, and greater than that under W1 at the same nitrogen level. Yield with the N1 treatment was higher than that with the N0 treatment, but not significantly different from that obtained with the N2 and N3 treatments. The W2 N1 treatment resulted in the highest water use and fertilizer agronomic efficiencies. Compared with local traditional practice(W3 N3), the net income and output-input ratio of W2 N1 were greater by 12.3 and 19.5%, respectively. These findings suggest that two irrigation events of 60 mm each coupled with application of 100 kg N ha~(–1) is sufficient to provide a high wheat yield during drought growing seasons in the NCP.     

室内球兰常见虫害及防控

以提高北方地区温室及家庭球兰种植水平为目的,介绍了球兰室内常见的盔蚧、粉蚧、蚜虫、蚂蚁、白粉虱和蛞蝓等害虫的简单形态、为害特点及发生规律,总结了适用于不同环境的防控技术,对温室及家庭养护球兰有一定借鉴意义。     

土壤深松和补灌对小麦干物质生产及水分利用率的影响

研究一次深松耕作后土壤水分对冬小麦籽粒产量和水分利用率的影响,为小麦节水高产栽培提供理论依据.于2008-2009和2009-2010两个小麦生长季,选用高产小麦品种济麦22,采取测墒补灌的方法,研究了深松+旋耕和旋耕2种耕作方式下土壤水分对小麦0-200 cm土层土壤含水量、干物质积累与分配、籽粒产量及水分利用率的影响.结果表明,(1)深松+旋耕40-180 cm土层土壤含水量低于旋耕处理;旗叶光合速率和水分利用率,开花后干物质积累量及其对籽粒的贡献率显著高于旋耕处理.(2)W3(补灌至0-140 cm土层土壤相对含水量播种期为85％,越冬期80％,拔节和开花期75％)成熟期0-200cm土层土壤含水量与W1(播种期80％,越冬期80％,拔节和开花期75％)和W2处理(播种期80％,越冬期85％,拔节和开花期75％)无显著差异;W3和W''3(播种期85％,越冬期85％,拔节和开花期75％)60-140 cm土层土壤含水量分别低于W4(播种期85％,越冬期85％,拔节和开花期75％)和W''4(播种期90％,越冬期85％,拔节和开花期75％)处理;W3和W''3灌浆中后期旗叶光合速率较高,开花后干物质积累量及其对籽粒的贡献率显著高于其他处理,获得高的籽粒产量和水分利用率.综合考虑籽粒产量、水分利用率和灌溉效益,在深松+旋耕条件下,两年度分别以W3和W''3为节水高产的最佳处理.     

乙烯应答因子W17基因RNAi表达载体的构建及小麦遗传转化

干旱、高盐和病虫害严重影响了作物的产量和品质.ERF(ethylene responsive factor)转录因子是介导生物和非生物胁迫响应的重要调控因子.本实验室从小麦中克隆到抗逆相关ERF转录因子W17基因,本研究以植物表达载体pAHC25为基础,构建了含有反向重复序列的RNAi表达载体pAHC-W17RNAi.采用基因枪法45枪轰击小麦品种新春9号幼胚材料2 379个,共获得115株T0代再生植株,其中12株为阳性转基因植株.半定量RT-PCR分析表明,转基因植株中W17基因及其调控的下游基因的表达水平均显著下降;表型鉴定发现转基因小麦苗期发育受到抑制.本研究为深入分析小麦ERF基因的功能与作用机制,进而通过分子育种进行小麦抗性改良奠定了基础.     

外源钙离子与南方菟丝子寄生对喜旱莲子草茎形态结构的影响

外源钙离子对植物响应外界环境胁迫具有重要作用.寄生植物对入侵植物具有显著的抑制作用.以入侵植物喜旱莲子草为研究对象,采用完全随机区组的实验设计分析不同钙离子浓度与南方菟丝子寄生对喜旱莲子草茎形态结构的影响,探讨外源钙离子在寄主植物响应寄生植物胁迫中的作用.研究结果表明南方菟丝子寄生可以显著改变喜旱莲子草茎的形态结构,如显著降低喜旱莲子草茎的总长、分枝数、分节数、茎直径和髓腔直径,显著增加茎的厚角厚度与皮层厚度.外源钙离子对喜旱莲子草茎总长、分枝数、分节数、茎直径、髓腔直径和维管束直径没有显著影响,但可增加喜旱莲子草茎的维管束数目,降低茎的节间长、厚角厚度与皮层厚度.外源钙离子与南方菟丝子寄生相互作用可以显著增加喜旱莲子草茎的厚角厚度与皮层厚度,表明南方菟丝子寄生与高浓度的钙离子对喜旱莲子草茎的厚角厚度和皮层厚度具有显著的拮抗的交互作用.这种交互作用可以提高寄主植物的防御能力,减少寄生植物对寄主植物的损伤.     

Association of host plant growth and weed occurrence with armyworm (Mythimna separata) damage in corn fields

To clarify association between armyworm (Mythimna separata) damage level and the corn growth and weed occurrence, we investigated corn plant height, stem diameter and vigor as well as weed coverage and biomass. The investigations were conducted at three locations of Shaanxi Province, China which were suffered seriously from armyworm. Significant correlations were found between the parameters analyzed. At stunted corn growth and presence of plenty of weeds, the armyworm damage tended to be heavy; oppositely, when corn grew well and weed density were low, armyworm harm was the minimal. Therefore, corn growing status and weed density can significantly affect armyworm damage level. Our results imply that promoting corn growth and timely removal of weeds are conducive to reducing armyworm occurrence.     

福建省2种新记录外来入侵植物

报道了福建省2种新记录外来入侵植物大翼豆Macroptilum lathroides(L.) Urban和牧地狼尾草Pennisetum polystachion (L.) Schult.,标本存放于华南农业大学林学院植物标本室(CANT).