杏树吐伦球坚蚧空间分布型及抽样技术研究

应用聚集度指标和回归分析,对杏园吐伦球坚蚧Rhodococcus turanicus Arch.空间分布型进行研究,结果表明:在中度受害杏园,吐伦球坚蚧越冬若虫和初孵若虫呈聚集分布,聚集度随虫口密度增大而减小;聚集原因与吐伦球坚蚧本身的生活习性有关;确定了不同种群密度下、不同允许误差下的最适抽样数.通过对不同方位虫口密度进行数据分析,结果表明,吐伦球坚蚧若虫在杏树各方位的聚集是随机的,各方位对整体抽样均无代表性.     

朝鲜球坚蚧及黑缘红瓢虫空间格局的地统计学研究

利用地统计学方法研究了不同时期朝鲜球坚蚧(Didesmococcus Koreanus Borchs)若虫及黑缘红瓢虫（Chilocorus rulidus Hope）幼虫种群的空间分布格局和空间相关性。结果表明,不同时期朝鲜球坚蚧若虫种九和黑缘红瓢虫幼虫种群的半变异函数均可拟合为球型,其空间格局为聚集型,在小尺度上,空间变异主要是由其空间自相关引起的,且不同时期格局变化不明显,变程分别为9.56-15.70m和18.83-19.74m之间。黑缘红瓢虫种群与朝鲜球坚蚧种群之间具有很强的追随关系,说明黑缘红瓢虫种群是朝鲜球坚蚧种群的优势天敌。     

球蚧蓝绿跳小蜂的研究

球蚧蓝绿跳小蜂是球坚蚧的重要天敌。该蜂寄生于球坚蚧的越冬若虫为致死性单寄生,寄生于球坚蚧雌成虫为非致死性过寄生,但显著降低球坚蚧的抱卵量。在新疆和田地区该蜂寄生于球坚蚧越冬若虫的寄生率为28．5％,寄生于雌成虫的寄生率为51．3％;在喀什地区寄生于球坚蚧雌成虫的寄生率为47％。描述了球蚧蓝绿跳小蜂的卵、幼虫、蛹的形态特征。叙述了球蚧蓝绿跳小峰世代生活史和习性,及其交配、产卵行为。表述球蚧蓝绿跳小峰与球坚蚧生活阶段对应关系。实施刮皮涂药措施防治球坚蚧,既能有效地防治球坚蚧,又可保护球蚧蓝绿跳小蜂。采集带蜂枝条插入装水塑料袋搬迁天敌,简单易行且效果好。     

草皮逍遥蛛等天敌对吐伦球坚蚧捕食作用的初步研究

采用HollingⅡ型和Ⅲ型模拟测定了草皮逍遥蛛等3种天敌对吐伦球坚蚧初龄若虫的捕食功能。结果表明：草皮逍遥蛛具有相当的食蚧能力,食量仅稍低于多异瓢虫,但远低于以食蚧为主的孪斑唇瓢虫。     

8种寄主植物对朝鲜球坚蚧(Didesmococcus koreanus Broch)的适合度及自然种群增长的影响

在室外对8种寄主植物上朝鲜球坚蚧的刺吸、产卵以及种群动态进行了系统调查,并运用选择性指数(SI)、嗜食性指数(PI)、危害指数(DI)和种群趋势指数(I)等4种指数系统定量评价了8种寄主对朝鲜球坚蚧的适合度以及自然种群增长等的影响.结果表明,好、中、弱3种生长势的寄主对朝鲜球坚蚧的适合度由高至低的顺序均是桃、梅、李、杏、苹果、梨、樱和山楂;在一个生长季节内,8种寄主适合度总体变化均表现为正态分布形,呈弱-强-弱态势,都以6月份的8种寄主适合度表现最高,且以生长势好的寄主最高,中等的次之,弱的最差.朝鲜球坚蚧更趋向于梅、桃、李和杏寄主上刺吸取食和产卵,且若蚧存活率、卵的孵化率以及羽化率均较高,自然种群增长最快,4种指数均较大(SI>0.875、PI>5.469、I>5.75、DI>1.049).桃、梅、李和杏寄主是该蚧的最适宜类寄主;苹果、梨和樱寄主植物是适宜类寄主;山楂为次适宜类寄主.PI与DI间回归方程为:PI=0.3389 DI(r0.01=0.937).8种寄主表皮毛密度、长度、皮层厚度和枝条直径等物理结构与适合度的强弱均呈负相关(r0.01=-0.976),其对该蚧刺吸取食和产卵等行为起到抑制作用.山楂表皮毛密度、长度、皮层厚度和枝条直径分别是最适宜类寄主枝条4种物理结构指标平均值的2.73、3.27、2.77倍和3.47倍.这些对抗蚧育种、预测测报以及优化防治策略等具有一定的指导意义.     

中国大球蚧属四新记录种

大球蚧属Eulecanium Cockerell 1893,此前我国记述有8种,即:格纹白球蚧Eulecaniumalbodermis Chen 1962、桤木裸蚧Eulecanium alnicola Chen 1962、刺槐球坚蚧Eulecanium circumfluumBorchs.1955、瘤大球坚蚧Eulecanium gigantea(Shinji,1935)、昆明球坚蚧Eulecanium kunmingiFerris 1950、日本球坚蚧Eulecanium kunoensis(Kuwana,1907)、桑名球坚蚧Eulecanium kuwanaiKanda 1934和黑带球坚蚧Eulecanium nigrivitta Borchs.1959。但其中桑名球坚蚧E.kuwanai,根据原     

黑缘红瓢虫生物学特性的研究

黑缘红瓢虫ChilocorusrubidusHope 1年发生 1代 ,以成虫在杂草、石缝中等处越冬 ,为朝鲜球坚蚧DidesmococcuskoreanusBorchs的重要天敌。主要分布在桃树、梅树等树上 ,对朝鲜球坚蚧有很强的控制作用。黑缘红瓢虫主要以幼虫捕食猎物为主 ,其幼虫对朝鲜球坚蚧雌蚧功能反应符合HollingⅡ模型 ,一昼夜最大捕食量为 8头。成虫主要起繁殖和扩散作用     

皱大球蚧(Eulecanium kuwanai)和瘤坚大球蚧(Eulecanium gigantean)地理种群的RAPD遗传分化

采用RAPD技术测定分析了河北省皱大球蚧和瘤坚大球蚧8个地理种群的遗传结构。结果表明：5种引物在8个种群中共产生了65条RAPD标记,各地理种群之间没有产生各自的特征标记;不同种群间的遗传相似程度与其地理间距呈反比;种群内的遗传相似程度比种间高。Shannon信息指数表明,皱大球蚧的平均遗传多样性高于瘤坚大球蚧,分别为0.3456和0.3225,说明物种不同,其变异程度也不同。     

皱大球蚧(Eulecanium kuwanai)和瘤坚大球蚧(Eulecanium gigantean)地理种群的RAPD遗传分化

采用RAPD技术测定分析了河北省皱大球蚧和瘤坚大球蚧8个地理种群的遗传结构。结果表明：5种引物在8个种群中共产生了65条RAPD标记,各地理种群之间没有产生各自的特征标记;不同种群间的遗传相似程度与其地理间距呈反比;种群内的遗传相似程度比种间高。Shannon信息指数表明,皱大球蚧的平均遗传多样性高于瘤坚大球蚧,分别为0.3456和0.3225说明物种不同,其变异程度也不同。     

30%强力杀蚧防治梅园朝鲜球坚蚧试验

30%强力杀蚧(Omethoate)微乳剂防治梅园朝鲜球坚蚧DidesmococcuskoreanusBorchs试验结果表明:800,1200倍液药后1～7d的防效均保持在94.5%以上,击倒力强,杀蚧效果快;药效期长,药后14d,防效仍达99%以上;其600,800和1200倍液之间防效差异不明显。600,800和1200倍液的防治效果与25%蚧死净乳油在药后3,5,7,14d的防效有显著差异,25%蚧死净乳油的持效时间均较短,药后3d防效就陆续下降,分别从89.92%降到88.56,81.41%和61.82%。而与40%杀扑磷(速扑杀)乳油相比其防治效果之间无显著差异。30%强力杀蚧微乳剂具有作用速度快,持效期长、对青梅安全性高,防治成本底的特点。     

Changes in lactate dehydrogenase activity in chicken tissues in hyperthyreosis in ontogenesis

The lactate dehydrogenase activity in reactions of lactate oxidation and synthesis was studied in subfractions of the chicken brain, heart and liver at the embryonal, early postembryonal and adult stages of development after thyroxine administration. It has been shown that during embryogenesis thyroxine predominantly enhanced the rate of lactate oxidation in the mitochondrial tissues. A marked increase in the lactate synthesis was found in cytoplasm of the adult chicken tissues. Specificity of enzyme activity alterations was detected in the chicken brain during ontogenesis after thyroxine administration.     

Role for dopamine in malonate-induced damage in vivo in striatum and in vitro in mesencephalic cultures

Defects in mitochondrial energy metabolism have been implicated in the pathology of several neurodegenerative disorders. In addition, the reactive metabolites generated from the metabolism and oxidation of the neurotransmitter dopamine (DA) are thought to contribute to the damage to neurons of the basal ganglia. We have previously demonstrated that infusions of the metabolic inhibitor malonate into the striata of mice or rats produce degeneration of DA nerve terminals. In the present studies, we demonstrate that an intrastriatal infusion of malonate induces a substantial increase in DA efflux in awake, behaving mice as measured by in vivo microdialysis. Furthermore, pretreatment of mice with tetrabenazine (TBZ) or the TBZ analogue Ro 4-1284 (Ro-4), compounds that reversibly inhibit the vesicular storage of DA, attenuates the malonate-induced DA efflux as well as the damage to DA nerve terminals. Consistent with these findings, the damage to both DA and GABA neurons in mesencephalic cultures by malonate exposure was attenuated by pretreatment with TBZ or Ro-4. Treatment with these compounds did not affect the formation of free radicals or the inhibition of oxidative phosphorylation resulting from malonate exposure alone. Our data suggest that DA plays an important role in the neurotoxicity produced by malonate. These findings provide direct evidence that inhibition of succinate dehydrogenase causes an increase in extracellular DA levels and indicate that bioenergetic defects may contribute to the pathogenesis of chronic neurodegenerative diseases through a mechanism involving DA.     

Scurvy in capybaras bred in captivity in Argentine

In order to determine if the absence of vitamin C in the diet of capybaras (Hydrochoerus hydrochaeris) causes scurvy, a group of seven young individuals were fed food pellets without ascorbic acid, while another group of eight individuals received the same food with 1 g of ascorbic acid per animal per day. Animals in the first group developed signs of scurvy-like gingivitis, breaking of the incisors and death of one animal. Clinical signs appeared between 25 and 104 days from the beginning of the trial in all individuals. Growth rates of individuals deprived of vitamin C was considerably less than those observed in the control group. Deficiency of ascorbic acid had a severe effect on reproduction of another population of captive capybaras. We found that the decrease in ascorbic acid content in the diet affected pregnancy, especially during the first stages. The results obtained suggest that it is necessary to supply a suitable quantity of vitamin C in the diet of this species in captivity.     

SSTR5 ablation in islet results in alterations in glucose homeostasis in mice

Somatostatin (SST) peptide is a potent inhibitor of insulin secretion and its effect is mediated via somatostatin receptor 5 (SSTR5) in the endocrine pancreas. To investigate the consequences of gene ablation of SSTR5 in the mouse pancreas, we have generated a mouse model in which the SSTR5 gene was specifically knocked down in the pancreatic beta cells (betaSSTR5Kd) using the Cre-lox system. Immunohistochemistry analysis showed that SSTR5 gene expression was absent in beta cells at three months of age. At the time of gene ablation, betaSSTR5Kd mice demonstrated glucose intolerance with lack of insulin response and significantly reduced serum insulin levels. Insulin tolerance test demonstrated a significant increase of insulin clearance in vivo at the same age. In vitro studies demonstrated an absence of response to SST-28 stimulation in the betaSSTR5Kd mouse islet, which was associated with a significantly reduced SST expression level in betaSSTR5Kd mice pancreata. In addition, betaSSTR5Kd mice had significantly reduced serum glucose levels and increased serum insulin levels at 12 months of age. Glucose tolerance test at an older age also indicated a persistently higher insulin level in betaSSTR5Kd mice. Further studies of betaSSTR5Kd mice had revealed elevated serum C-peptide levels at both 3 and 12 months of age, suggesting that these mice are capable of producing and releasing insulin to the periphery. These results support the hypothesis that SSTR5 plays a pivotal role in the regulation of insulin secretion in the mouse pancreas.