Coevolved crypts and exocrine glands support mutualistic bacteria in fungus-growing ants

Attine ants engage in a quadripartite symbiosis with fungi they cultivate for food, specialized garden parasites, and parasite-inhibiting bacteria. Molecular phylogenetic evidence supports an ancient host-pathogen association between the ant-cultivar mutualism and the garden parasite. Here we show that ants rear the antibiotic-producing bacteria in elaborate cuticular crypts, supported by unique exocrine glands, and that these structures have been highly modified across the ants' evolutionary history. This specialized structural evolution, together with the absence of these bacteria and modifications in other ant genera that do not grow fungus, indicate that the bacteria have an ancient and coevolved association with the ants, their fungal cultivar, and the garden parasite.     

4种猛蚁的巢穴结构及巢内生物

敏捷厚结猛蚁Pachycondyla astuta Smith、聚纹双刺猛蚁Diacamma rugosum(Le Guillou)、横纹齿猛蚁Odonto-ponera transversa(Smith)和猎镰猛蚁Harpegnathos venator(Smith)是我国东部和南部地区比较常见的猛蚁,可捕食林木白蚁,是一类潜在的天敌昆虫.通过挖巢的方法对这4种猛蚁的筑巢环境、巢穴结构和巢内生物进行了研究.结果表明,4种猛蚁的巢穴均为地下巢,多建在橡胶林、荔枝林等林间空地;结构比较简单,深度一般不超过0.6 m,巢室仅有几个至数十个,在土壤中分布无规则至分层排列.巢穴内部或周围常可见到膜翅目、等翅目昆虫以及土壤小型多足类和等足类动物.     

氟虫腈饵剂防控红火蚁的田间药效试验

以含0.05％氟虫腈为有效成分与多种天然物质配制饵剂,撒于红火蚁(SolenopsisinvatBuren)蚁巢上,药剂中的引诱剂吸引红火蚁取食,将饵剂带入巢内,并通过红火蚁在巢内交哺喂食行为将药剂传递给其它各品级个体,引起全巢红火蚁中毒死亡.结果表明,0.05％氟虫腈杀蚁饵剂对红火蚁具有良好的控制效果,药后15d开始进入防效高峰期,25～30d防效达到最佳.0.05％氟虫腈杀蚁饵剂药后30d对工蚁的防治效果达93.39％～100.00％;灭巢效果达95.84％～100.00％;药后50d,蚁群级别降低率达83.33％～100.00％,显著优于对照药剂.     

基于计算机视觉技术的红火蚁蚁巢探测

为探讨基于计算机视觉技术对红火蚁蚁巢进行探测识别的可行性,研究了利用数字图像处理技术提取红火蚁蚁巢特征参数,通过数学形态学对数字图像进行目标提取和识别。采用图像识别红火蚁蚁巢土建立了HSV彩色空间模型。研究结果表明,各红火蚁蚁巢土和普通土样本的H分量差异明显,特别是普通土H分量明显大于红火蚁蚁巢土,一般土壤H值大于30,而对于红火蚁蚁巢土土壤的H值小于30。因此,H分量可作为识别红火蚁蚁巢土的一项特征参数。当色调通道的平均值H30时,即可判定为红火蚁蚁巢土。研究结果说明基于计算机视觉技术对红火蚁蚁巢进行检测识别是可行的。     

Code of ant-plant mutualism broken by parasite

Newly discovered Phyllobaenus beetles are parasites of a mutualism. Piper ant-plants in tropical forests provide lipid and protein-rich food cells and shelter for Pheidok bicornis ants while the ants remove small herbivores and vines from the foliage. In contrast to all other ant-plants, Piper ant-plants produce food bodies only when Pheidole bicornis is present in the plant. However, Phyllobaenus beetles can stimulate the plants to produce food bodies as if ants were present. The beetles then inhabit the plant, exploiting nest sites and food produced by the plants for ants. These beetles may also prey on ant brood, depriving the plants of resources and services provided by the ants.     

秦岭楼观台油松林地3种土栖性蚂蚁巢内真菌多样性研究(英文)

研究比较了秦岭楼观台油松林地日本弓背蚁(Camponotus japonicus)、铺道蚁(Tetramo-riumcaespitum)及日本黑褐蚁(Formicajaponica)3种蚂蚁蚁巢内外土壤真菌多样性的差异。研究结果表明:(1)从3种蚂蚁蚁巢及无蚂蚁栖居的土壤样品中共分离到15种真菌,无蚂蚁栖居土壤中真菌种类是3种蚂蚁巢内真菌种类的2.0~3.5倍;日本弓背蚁巢内平均cfu.g-1最低,明显低于无蚂蚁栖居的土壤(P<0.05),另外2种蚂蚁巢内及其无蚂蚁栖居的土壤平均cfu.g-1差异不明显(P>0.05)。(2)3种蚂蚁蚁巢内的真菌多样性指数(H′)均显著低于无蚂蚁栖居的土壤(P<0.05),但在3种蚂蚁蚁巢之间无显著差异(P>0.05);3种蚂蚁及无蚂蚁栖居的土壤的真菌均匀度指数(E)之间无显著差异(P>0.05)。(3)3种蚂蚁巢内真菌种类组成明显不同,形成各自特殊的真菌群落;蚁巢中分布的真菌种类几乎都可发现于无蚂蚁栖居的土壤,但其在蚁巢内的分布均大于无蚂蚁栖居的土壤。不同蚂蚁蚁巢内及无蚂蚁栖居的土壤中真菌组成及其多样性的差异与土壤微环境以及不同蚂蚁种群、筑巢习性及其对真菌的防卫机制密切相关。     

Use of a sound-based vibratome by leaf-cutting ants

Leaf-cutting ants harvest fresh vegetation that they then use as food for symbiotic fungi. When cutting leaf fragments, the ants produce high-frequency vibrations with a specialized organ located on the gaster. This stridulation behavior is synchronized with movements of the mandible, generating complex vibrations of the mandibles. The high vibrational acceleration of the mandible (up to three times the gravitational force at peak acceleration at about 1000 hertz) appears to stiffen the material to be cut. An identical effect is achieved when soft material is sectioned with a vibratome. This hypothesis is supported by experiments simulating the cutting process with vibrating isolated mandibles: When tender leaves were cut, the vibration of the mandible reduced force fluctuations and thus permitted a smoother cut to be made.     

浙江温岭野生观赏植物资源

野外调查表明,浙江省温岭市共有野生观赏植物122科307属374种及变种,分别占该市维管束植物科属种总数的62．6％,35．2％和21．1％。按其园林用途划分为园景树、庭荫树、行道树、绿篱植物、垂直绿化植物、盆栽植物、花坛和花境植物、切花植物、水体绿化植物、草坪植物和地被植物共11个大类。温岭野生观赏植物具有资源丰富,类别齐全,特色资源突出,又具有一定珍稀资源的特点。表2参31     

陕西省蚂蚁区系研究

对陕西蚂蚁的种群及区系特点研究结果表明:分布于陕西的蚂蚁目前共计有79种,分属于4亚科,并列出了陕西蚂蚁名录;陕西蚂蚁区系成分可分为古北种、广布种、全北种、东洋种,其中以古北种和东洋种比例较大;根据气候带及秦岭的特殊环境,陕西蚂蚁区系被分为4个亚区.并对陕西蚂蚁的属(种)数量及经济价值进行了探讨.     

The evolution of agriculture in ants

Cultivation of fungi for food by fungus-growing ants (Attini: Formicidae) originated about 50 million years ago. The subsequent evolutionary history of this agricultural symbiosis was inferred from phylogenetic and population-genetic patterns of 553 cultivars isolated from gardens of "primitive" fungus-growing ants. These patterns indicate that fungus-growing ants succeeded at domesticating multiple cultivars, that the ants are capable of switching to novel cultivars, that single ant species farm a diversity of cultivars, and that cultivars are shared occasionally between distantly related ant species, probably by lateral transfer between ant colonies.     

Territoriality and the origin of slave raiding in leptothoracine ants

The slave-raiding behavior of Harpagoxenus canadensis closely resembles the territorial behavior of its host species, Leptothorax muscorum. Of primary importance is the discovery that both species of ants recruit nest mates into battle using an alarm-recruitment system which is a probable evolutionary precursor of more specialized forms of slave-raiding recruitment. The behavior of these species supports the hypothesis that slave raiding in leptothoracine ants evolved from territorial behavior.     

Postsecretory hydrolysis of nectar sucrose and specialization in ant/plant mutualism

Obligate Acacia ant plants house mutualistic ants as a defense mechanism and provide them with extrafloral nectar (EFN). Ant/plant mutualisms are widespread, but little is known about the biochemical basis of their species specificity. Despite its importance in these and other plant/animal interactions, little attention has been paid to the control of the chemical composition of nectar. We found high invertase (sucrose-cleaving) activity in Acacia EFN, which thus contained no sucrose. Sucrose, a disaccharide common in other EFNs, usually attracts nonsymbiotic ants. The EFN of the ant acacias was therefore unattractive to such ants. The Pseudomyrmex ants that are specialized to live on Acacia had almost no invertase activity in their digestive tracts and preferred sucrose-free EFN. Our results demonstrate postsecretory regulation of the carbohydrate composition of nectar.     

Tournaments and slavery in a desert ant

Many species of ants engage in physical fighting when territorial borders are challenged. In contrast, colonies of the honeypot ant species Myrmecocystus mimicus conduct ritualized tournaments, in which hundreds of ants perform highly stereotyped display fights. Opposing colonies summon their worker forces to the tournament area by means of an alarm-recruitment system. When one colony is considerably stronger than the other, the tournament quickly ends, and the weaker colony is raided and its ants "enslaved." This is the first example of intraspecific slavery recorded in ants.     

藏东南色季拉山蚂蚁物种的分布格局

为了揭示藏东南地区蚂蚁的生态学规律,采用样地调查法和搜索调查法首次研究了色季拉山蚂蚁物种的分布格局。在色季拉山记载蚁科昆虫3亚科14属31种,其中,猛蚁亚科2属3种,切叶蚁亚科7属17种,蚁亚科5属11种。在色季拉山地区,大多数蚂蚁物种（大约2/3）对高山环境的适应性较弱,仅分布于3000m以下的低海拔区域;分布于30...     

秦岭地区2种蚂蚁巢内土壤理化性质和微生物量的相关性研究

研究了秦岭牛背梁自然保护区森林生态系统中2种优势蚂蚁(日本弓背蚁Camponotus japonicus和敏捷扁头猛蚁Pachycondyla astuta)的营巢活动对林地土壤理化性质及其微生物量的影响。结果表明:3种不同微生境(日本弓背蚁巢内、敏捷扁头猛蚁巢内及蚁巢外对照)土壤的有机质、全氮、速效氮和速效钾含量均存在显著差异(p<0.05),表现为敏捷扁头猛蚁巢内>日本弓背蚁巢内>巢外土壤;全磷和速效磷的含量虽然无显著差异(p>0.05),但与蚁巢外土壤相比,日本弓背蚁巢内速效磷含量下降了31.41%,敏捷扁头猛蚁巢内速效磷含量下降了15.09%;三者间含水量差异亦存在显著差异(p<0.05),且蚁巢内土壤均较巢外潮湿;pH值差异不显著,但蚁巢内土壤比巢外土壤略显酸性。营巢活动对土壤微生物量也产生明显影响(p<0.05),2种蚂蚁蚁巢内细菌、放线菌及真菌的cfu/g数量均显著大于巢外土壤(p<0.05),而敏捷扁头猛蚁巢内3类微生物cfu/g数量又显著大于日本弓背蚁巢内(p<0.05)。土壤理化性质和微生物量的相关性分析表明:日本弓背蚁和敏捷扁头猛蚁巢内土壤有机质、全氮、速效氮、速效钾含量与其土壤中细菌、放线菌、真菌的cfu/g数量呈显著或极显著正相关;全磷含量与土壤微生物量呈不同程度的正相关;但2种蚂蚁巢内的土壤速效磷含量及pH值则与土壤微生物cfu/g数量呈显著负相关。以上结果表明,蚂蚁的筑巢活动可显著影响其巢内土壤的养分含量和微生物量,致使土壤异质性增强,从而对维持森林生态系统中物质能量循环产生重要的影响作用。     

瑞丽市 3 种类型柠檬园地表蚂蚁群落多样性研究

为探讨覆膜对柠檬园地表蚂蚁群落的影响,于2016年4月和7月采用陷阱法对云南省瑞丽市覆膜种植和常规种植模式下3种类型柠檬园地表蚂蚁群落进行调查。结果表明,柠檬园RG采集地表蚂蚁17种276头;柠檬园RH采集地表蚂蚁22种527头;柠檬园RI采集地表蚂蚁16种273头。3种类型柠檬园间地表蚂蚁相对多度和物种丰富度均有显著差异,柠檬园RH中地表蚂蚁的相对多度和物种丰富度均显著高于柠檬园RG和柠檬园RI。3种类型柠檬园间地表蚂蚁群落结构互不相似。覆膜降低了柠檬园地表蚂蚁群落的相对多度和物种丰富度,除草剂对柠檬园地表蚂蚁的相对多度和物种丰富度无影响,但可以改变地表蚂蚁群落结构。     

基于认知程度评估的红火蚁 管理策略与方式探讨

采用问卷调查的方法对南沙区132 个社区/村当地居民对红火蚁认知程度进行调查。结果发现、南沙区 居民对红火蚁的了解程度较高、其中65.2%居民知道红火蚁;对红火蚁的了解途径中、野亲眼所见冶所占比例最高、为 57.78%、其次是从电视上得知、为14.43%;86.84%居民所在地区发现有红火蚁、90.93%居民周围有人知道红火蚁。在 发现红火蚁后、52.35%居民会向相关部门反映、38.01%居民会使用工具进行破坏;68.78%居民3 年前就已经听说当 地有红火蚁发生;48.08%居民认为红火蚁入侵对人身健康产生影响;59.59%居民被红火蚁叮咬过、且86.32%居民会 有痛痒、红肿、脓包的症状;69.50%居民在被叮咬后知道处理方法、其中53.88%居民会涂抹药膏、30.53%会去医;就 医;62.09%居民会关心入侵生物相关的信息;56.37%居民了解红火蚁相关工作内容;89.95%居民对红火蚁的宣传、防 治工作感到基本满意;在红火蚁相关工作中、37.47%居民建议应该加强防控力度、21.98%居民认为应该加强宣传。通 过调查所反映的问题、提出解决的方法和建议。     

Ancient tripartite coevolution in the attine ant-microbe symbiosis

The symbiosis between fungus-growing ants and the fungi they cultivate for food has been shaped by 50 million years of coevolution. Phylogenetic analyses indicate that this long coevolutionary history includes a third symbiont lineage: specialized microfungal parasites of the ants' fungus gardens. At ancient levels, the phylogenies of the three symbionts are perfectly congruent, revealing that the ant-microbe symbiosis is the product of tripartite coevolution between the farming ants, their cultivars, and the garden parasites. At recent phylogenetic levels, coevolution has been punctuated by occasional host-switching by the parasite, thus intensifying continuous coadaptation between symbionts in a tripartite arms race.     

福建名茶铁观音的土宜条件

在我省丰产的铁观音茶园土壤中,常量营养元素含量较高,但茶叶品质与土壤母岩密切相关.优质铁观音茶园土壤发育于基性辉绿岩.据微量元素分析结果,凡优质的铁观音茶园土壤和鲜叶中 Mn,Cu,Zn 含量均达较高水平.说明 Mn,Cn,Zn 对提高铁观音茶叶品质有重要作用,而气候影响则是次要的.