越北腹露蝗(Fruhstorferiola tonkinensis Will.)发生与粤北河滩植物群落的关系

用普查法研究广东省北部地区越北腹露蝗Fruhstorferiola tonkinensis Will.严重发生河滩植物群落,鉴定出分属于43个科的植物106种,同时记录下植物群落中植物种名、平均高度、聚生多度、总覆盖率、物候相和生活力,分析了河滩植物群落的植物相似性和丰富度以及优势种数量特征和属性标志,结果表明河滩植被的搭配和空间分布为越北腹露蝗在粤北大发生提供了独特的生境;另外结合各河滩植物群落进行越北腹露蝗1龄蝗蝻虫口密度调查,根据调查结果对越北腹露蝗发生与植物群落的关系进行偏相关分析,分析结果显示枫杨是越北腹露蝗最嗜性植物,其覆盖度与越北腹露蝗发生密度呈极显著相关,偏相关系数为0.856(F＝32.9201,P＝0.0001),小簕竹是越北腹露蝗非嗜性植物,其覆盖度与越北腹露蝗的发生密度呈显著的负相关,偏相关系数为-0.613(F＝0.1617,P＝0.021),据此提出了一些控制粤北河滩越北腹露蝗的新举措.     

越北腹露蝗卵寄生蜂：东方蝗卵蜂

东方蝗卵蜂Scelio oriemalis Dodd是越北腹露蝗Fruhstorferiola tonkinensis Will.卵的寄生性天敌.2004-2006年对广东省北部越北腹露蝗卵粒和卵块寄生率分别为43.18%和89.34%.东方蝗卵蜂产卵在越北腹露蝗卵中,幼虫期为2龄,每粒被寄生的蝗卵只出l头蜂.东方蝗卵蜂的产卵系统发达,不仅骨化程度高,而且具有伸缩性.雌雄件比约为1:0.6,羽化后即可交配.以5%的葡萄糖溶液喂养成蜂,最多可存活31 d.东方蝗卵蜂可能是某些年份越北腹露蝗种群下降的重要因子.     

越北腹露蝗成虫口器的感器

利用扫描电子显微镜观察了越北腹露蝗Fruhstorferiola tonkinensis Will.成虫口器的上唇、下颚须和下唇须上的感器形态和数量分布.结果表明:越北腹露蝗下唇须3节,下颚须5节,在上唇和唇基、下唇须和下颚须端点及各节上具有感器.口器感器共5种:毛形感器(sensilla trichodea)、刺形感器(sensilla chaetica)、锥形感器(sensilla basiconica)、腔锥形感器(sensilla coeloclnica)和盾形感器(sensilla scutellatum),其中毛形感器、刺形感器、锥形感器分别着生于上唇和唇基、下唇须和下颚须端点及各节表面,腔锥形感器(sensilla coeloclnica)只限于上唇外表面,盾形感器只限于下唇须和下颚须端点.推测了口器感器的功能,为了解越北腹露蝗的取食行为奠定基础.     

水浸对越北腹露蝗卵的影响

越北腹露蝗Fruhstorferiola tonkinensis Will.是广东北江流域河滩蝗虫的优势种。以不浸水的蝗卵为对照,研究滞育期蝗卵浸水5～95d和胚胎发育期蝗卵浸水1～30d对卵孵化率和历期的影响。结果表明,随浸水时间的增加,孵化率下降,卵发育延迟;滞育期蝗卵经受95d的浸水仍有8.01%存活,而胚胎发育期蝗卵浸水30d后全部死亡,滞育期蝗卵比胚胎发育期蝗卵具有更强的耐浸水能力。说明越北腹露蝗以卵滞育的形式发展了对水浸胁迫的适应。     

中国黑卵蜂属一新记录种——东方蝗卵蜂

记述黑卵蜂属Scelio中国1新记录种:东方蝗卵蜂Scelio orientalis Dodd,并报道该寄生蜂的新寄主:越北腹露蝗Fruhstorferiola tonkinensis Will.。     

型变过程中亚洲小车蝗体内保幼激素滴度及其代谢相关基因表达量的变化

【目的】本研究旨在明确亚洲小车蝗Oedaleus asiaticus在不同发育阶段和型变过程中的保幼激素(juvenile hormone, JH) JHⅢ滴度及其代谢相关基因表达量的变化情况，为阐明保幼激素调控亚洲小车蝗型变中的生理功能奠定基础。【方法】采用高效液相色谱法测定散居型和群居型亚洲小车蝗不同发育阶段(4和5龄若虫及1, 4, 7, 10, 13和20日龄成虫)和3龄若虫群居化处理1, 3, 5和7 d时亚洲小车蝗血淋巴中的保幼激素JHⅢ的滴度变化；用qRT-PCR检测在群居化处理亚洲小车蝗3龄若虫1, 3, 5和7 d时保幼激素代谢相关的3种基因保幼激素酯酶(juvenile hormone esterase, JHE)基因、保幼激素甲基转移酶(juvenile hormone methyltransferase, JHAMT)基因和保幼激素环氧水解酶(juvenile hormone epoxide hydrolase, JHEH)基因的表达量；利用JHⅢ浸液处理散居型亚洲小车蝗3龄若虫后进行群居化处理，测定亚洲小车蝗型变率。【结果】JHⅢ在亚洲小车蝗血淋巴中的滴度甚微...     

祁连山红腹牧草蝗雌雄虫空间格局及关联性

应用地统计学的方法,研究了祁连山北坡石羊河上游,6—10月之间红腹牧草蝗Omocestus haemorrhoidalis(Charpentie)雌雄虫的空间分布格局、动态变化及空间相关性。结果表明:红腹牧草蝗雌雄虫的半变异函数为球状模型与高斯模型,二者空间分布类型相同,均呈聚集分布;随时间的变化均呈现"扩散-聚集-扩散-聚集"的动态特征,7—8月之间雌虫的变化强度明显强于雄虫;二者的模糊贴近度指数在0.53～0.71之间,且指数随红腹牧草蝗的生长呈逐渐增加到减少的变化特征,表明雌雄虫在数量与空间上有较强的跟随关系,且跟随关系随红腹牧草蝗的生长发生明显的阶段性变化。     

拉缘蝽空间格局及抽样技术的研究

拉缘蝽空间格局测定结果表明,拉缘蝽的1—3龄若虫、4—5龄若虫和成虫等各虫态的空间格局均属于聚集分布,拉缘蝽1—3龄若虫聚集度最高,4—5龄若虫聚集度下降,成虫聚集度更低。在拉缘蝽空间格局的基础上,确定了Kuno风险决策序贯抽样表和1wao—Kuno（1968）理论抽样数。     

根土蝽越冬规律的研究

1985～1986年调查结果表明,根土蝽以若虫和成虫越冬,而以若虫为主,占总虫量的68.62％;其中1龄占16.89％,2龄占10.11％,3龄占11.11％,4龄占19.63％,5龄占10.89％。雌雄成虫各占50.89％、49.11％。在垂直分布上,根据地温变化情况,0～10cm的土层中越冬期间地温均在10℃以下,未见到各种虫态的分布;在10～80cm土层中,地温为11.11—14.42℃,各虫态群体形成不同的集中深度,1龄在10～30cm;2龄在20～40cm,3龄、4龄在20～50cm,5龄在30～50cm,雌成虫在40～60cm,雄成虫在30～60cm,70cm处总虫量为10头左右。这说明虫龄越小,越冬深度越浅;若虫越冬深度又比成虫浅;经采用方差分析,测验各群体的垂直分布在不同深度的结构有明显差异。     

越北腹露蝗卵的过冷却特性

利用热电偶法测定越北腹露蝗FruhstorferiolatonkinensisWill卵的过冷却点。结果表明,越北腹露蝗卵的过冷却点随季节变化而变动。卵的平均过冷却点从2004年9月初(刚产的卵)的-16.0℃显著下降到2005年1月的-24.7℃,随后卵的过冷却点显著增加到2005年3月的-10.7℃。滞育卵的平均过冷却点(-20.1℃)低于滞育后的平均过冷却点(-12.4℃)。滞育卵在5℃下适应30d后平均过冷却点显著减小到-25.9℃,而在30℃下适应30d后平均过冷却点显著增加到-8.2℃。     

高山草原狭翅雏蝗的生物学特性及种群空间分布

在甘肃省夏河县甘加高山草原,对狭翅雏蝗的发生期、食量、空间格局及动态进行了系统研究。结果表明,该虫1年发生1代,以卵在土中越冬,翌年5月下旬至6月上旬开始孵化出土,6月中旬至下旬为孵化出土盛期,蝗蝻多数为4龄,少数(约23％)为5龄,整个蝗蝻期为70．45±15．76d,成虫寿命42．36±13.46d;取食量随龄期增大而增大,蝗蝻期平均食量为368．3mg,成虫期平均食量为743．8mg,狭翅雏蝗在前期低龄蝗蝻阶段为聚集分布,高龄蝗蝻及成虫阶段以均匀分布和随机分布为主。     

Relationship of occurrence of Fruhstorferiola tonkinensis Will. and plant communities on riversides in northern Guangdong Province, China

Plant communities on riversides in northern Guangdong Province were investigated with all-survey method, where a kind of native grasshopper Fruhstorferiola tonkinensis Will. broke out severely. 108 plant species belonging to 43 families were identified, and some plant indexes in those plant communities including their name, average height, congregation index, total coverage rate, phenological phase and biod were noted. In addition, plant comparability, plant abundance, quantity character and attribute symbol of dominant species in plant communities on riversides were studied. The results showed that the arrangement and distribution of vegetations on riversides offered a favorable habitat for F. tonkinensis. Moreover, the density of first instar nymphs of F. tonkinensis in plant communities was calculated. The results of partial correlation analysis (PCA) about the relationship between plant communities and occurrence of F. tonkinensis showed that Pterocarya stenoptera C. DC. was the most palatable plant to F. tonkinensis, presenting a very significantly positive correlation between coverage rate of P. stenoptera and occurrence of F. tonkinensis. The partial correlation coefficient (PCC) was 0.856072 (F=32.92012, P=0.0001). Bambusa flexuosa was a non-preferable plant of F. tonkinensis, presenting a significantly negative correlation between them, and the partial correlation coefficient was ?0.607920 (F=0.16173, P=0.0211). Those results would help us to propose some approaches for the ecology control of F. tonkinensis on riversides in northern Guangdong Province.     

Analysis of the spatio-temporal distribution of Eurygaster integriceps (Hemiptera: Scutelleridae) by using spatial analysis by distance indices and geostatistics

Eurygaster integriceps Puton (Hemiptera: Scutelleridae) is the most serious insect pest of wheat (Triticum aestivum L.) and barley (Hordeum vulgare L.) in Iran. In this study, spatio-temporal distribution of this pest was determined in wheat by using spatial analysis by distance indices (SADIE) and geostatistics. Global positioning and geographic information systems were used for spatial sampling and mapping the distribution of this insect. The study was conducted for three growing seasons in Gharamalek, an agricultural region to the west of Tabriz, Iran. Weekly sampling began when E. integriceps adults migrated to wheat fields from overwintering sites and ended when the new generation adults appeared at the end of season. The adults were sampled using 1- by 1-m quadrat and distance-walk methods. A sweep net was used for sampling the nymphs, and five 180° sweeps were considered as the sampling unit. The results of spatial analyses by using geostatistics and SADIE indicated that E. integriceps adults were clumped after migration to fields and had significant spatial dependency. The second- and third-instar nymphs showed aggregated spatial structure in the middle of growing season. At the end of the season, population distribution changed toward random or regular patterns; and fourth and fifth instars had weaker spatial structure compared with younger nymphs. In Iran, management measures for E. integriceps in wheat fields are mainly applied against overwintering adults, as well as second and third instars. Because of the aggregated distribution of these life stages, site-specific spraying of chemicals is feasible in managing E. integriceps.     

Phase-related morphological changes induced by [His7]-corazonin in two species of locusts, Schistocerca gregaria and Locusta migratoria (Orthoptera: Acrididae)

The effects of a neurohormone, [His(7)]-corazonin, on phase-related morphological traits (F/C and E/F ratios; F = length of the hind femur, C = maximum width of the head; E = length of fore wing) were re-examined in the desert locust, Schistocerca gregaria Forsk?l. The F/C ratio was significantly different between adults with five and six nymphal instars, respectively, indicating that they need to be analysed separately. Injections of the synthesized peptide (1 nmol) into individually-reared (solitary) nymphs at the second and third instars caused a shift in classical morphometric ratio towards the value typical for crowded (gregarious) individuals in both sexes. The E/F ratio, which is smaller in solitary locusts than in gregarious ones, was also influenced significantly by injections of [His(7)]-corazonin into individually-reared locusts. The effect of [His(7)]-corazonin on E/F ratios was shown more clearly when the nymphs were injected at a higher dose (2 nmol) at the beginning of the third instar. Single injections of the peptide into individually-reared nymphs at different instars revealed that the earlier the injection the larger the 'gregarizing' effects of the peptide on F/C and E/F ratios. The same tendency was also detected in Locusta migratoria Linnaeus. These results supported the hypothesis that [His(7)]-corazonin plays an important role in the control of phase polymorphism in locusts.     

Changes in learning ability and mechanism during development of grasshopper nymphs, Melanoplus bivittatus

Abstract. In an experimental arena, Melanoplus bivittatus (Say) (Orthoptera: Acrididae) nymphs of four stadia were observed to determine whether they learn to associate food with positional or light-related cues. Nymphs were observed for 4 h in the arena containing one yellow box and one green box, then they were trained by placing food in the green box overnight. Following training, the responses of nymphs to green and yellow boxes were observed for a second 4 h period.
Before training, nymphs of all stadia visited the yellow box more frequently than the green box. Training did not affect the behaviour of second-stadium nymphs, but training increased the relative frequency of visits to the green box by third, fourth and fifth instars. Effects of training on duration of visits to boxes were not evident. Investigations of the mechanism of learning showed that positional cues were used by third-stadium nymphs, but that fourth and fifth instars responded to light-related cues. The progression from no learning in second instars, through use of positional cues by third instars, to use of light-related cues by fourth and fifth instars is probably associated with the greater mobility, greater food consumption, and more varied diet of older nymphs.     

松突圆蚧空间分布型的研究

应用聚集度指标和回归分析,对松突圆蚧空间分布型进行测定,结果表明：松突圆蚧的若虫在松林中呈聚集分布,聚集度随虫口密度增大而增强;而成虫在松林中呈均匀分布,从而确定出不同种群密度下最适抽样数。通过林间调查和数理统计分析,结果表明：松突圆蚧在松树枝条的东、南、西、北不同方位,以及松树树冠的上、中、下不同层次和幼林、中龄林、成林不同树龄的松林之间的虫口数量差异不显;但在郁闭度不同的松林中虫口数量存在着显差异。     

蒙古寒蝉成、若虫触角形态及若虫龄期判别研究（半翅目：蝉科）

对蒙古寒蝉若虫与成虫的触角感器进行了研究,并结合不同龄期若虫触角的形态特征,采用Dyar法则与“头宽—龄期”的回归曲线验证,初步断定蒙古寒蝉若虫具有4个龄期。不同龄期若虫与成虫的触角形态差异显著,触角感器的种类、数量和分布也明显不同,其差异或与若虫和成虫的生态位不同密切相关。     

黑胸散白蚁幼期不同品级的发育和分化

在黑胸散白蚁Reticulitermes chinensis发育和分化过程中,发现有假工蚁、假若蚁两种虫态。假工蚁由6龄和7龄工蚁转化发育而来,假若蚁由4龄和5龄若蚁转化发育而来。显微测量结果表明,黑胸散白蚁的胚后发育主要包括2个龄期的幼蚁期、6个以上龄期的工蚁期、4个龄期的若蚁期和有翅成虫。在此基础上分析了其他虫态的分化来源,发现兵蚁由3～7龄工蚁分化发育而来,翅鳞型和长翅芽型补充生殖蚁由6龄若蚁转化发育而来,短翅芽型补充生殖蚁由4龄和5龄若蚁转化发育而来,微翅芽型补充生殖蚁既可由4～6龄工蚁转化发育而来,又可由假工蚁和假若蚁转化发育而来,无翅型补充生殖蚁由3～7龄工蚁转化发育而来。提出了黑胸散白蚁群体中不同品级个体的可能分化途径。     

Effects of a juvenile hormone analog, pyriproxyfen, on the apterous form of Lipaphis erysimi

Effects of a juvenile hormone analog, pyriproxyfen, on various developmental stadia of the apterous form of the turnip aphid, Lipaphis erysimi (Kaltenbach), were bioassayed at three concentrations (50, 100, and 150 mg [AI]/l) in the laboratory. Supernumerary-molted nymphs with 1-3 extra molts were found when the first three nymphal instars were treated, and all these nymphs died prematurely. In contrast, all treated fourth instar nymphs molted normally to adults. The longevity of all pyriproxyfen-treated L. erysimi nymphs and adults and the fecundity of treated adults were reduced by 50%. Higher concentrations of pyriproxyfen (100 and 150 mg [AI]/l) caused sterility in adults from treated fourth instars; whereas the lowest concentration (50 mg [AI]/l) did not cause any adult sterility. A majority of adults from treated fourth instars and treated adults produced normal nymphs, and some adults produced dead nymphs with normal appendages or dead and deformed nymphs without any appendages. Normal nymphs produced by the adults from treated adults or treated at fourth instars developed more slowly from first instar to adult than the water-treated nymphs, and all adults in the new generation apparently reproduced normally. The potential role of pyriproxyfen in a vegetable aphid IPM program was discussed.     

Life cycle and seasonal development of post-embryonic Argas reflexus (Acari: Argasidae) at two thermally different locations in Central Europe

Seasonal development was investigated in the pigeon tick, Argas reflexus (F.) over a 5-year period. The ticks were kept in desiccators at two deposition sites with different temperature conditions: a warmer attic and a cooler outdoor aviary. The life cycle of A. reflexus consists of the egg, larva, a variable number of two to four nymphal instars and the adult stage. In the cooler aviary, the ticks passed, on average, fewer nymphal instars than in the attic. At both locations, ecdysis of the nymphs and adults occurred only during the summer months, with peak numbers of ticks finishing the moult in August. This consistent pattern was evident irrespective of the feeding date of the preceding developmental stage or the year of observation. The results strongly suggest that nymphs II, nymphs I and larvae fed later than in mid-July, August or September, respectively, entered a state of diapause and, thus, overwintered in the engorged state. Argas reflexus nymphs II from a laboratory stock that were deposited inside the attic showed a remarkably different seasonal pattern of development, even more than 1 year after their deposition. This suggests that a circannual rhythm may be involved in the ticks' seasonal timing. Mortality of the engorged ticks (from repletion to ecdysis of the following stage/instar) was below 1.5% in most cases, irrespective of the season and the location. Unfed larvae survived for a maximum of one year inside the attic, whereas the median survival period of unfed nymphs was at least 3 years at the same location. Based on the present results, the generation time from (F1) egg deposition to oviposition in the F2 generation might be 3-11 years in Central European A. reflexus, depending on the course of development (two or three nymphal instars) and the number of gonotrophic cycles (probably up to six) of the F1. The life span of a single tick might take approximately 7-11 years or even longer.