Bt水稻对青翅蚁形隐翅虫存活及捕食功能的影响

【目的】以稻田中重要捕食性天敌青翅蚁形隐翅虫Paederus fuscipes Curtis为研究对象,探讨在室内条件下青翅蚁形隐翅虫取食转Bt基因水稻上的褐飞虱后对其存活率和捕食功能的影响。【方法】在室内条件下,取食通过用一直取食转Bt水稻的褐飞虱Nilaparvata lugens(St?l)来饲养青翅蚁形隐翅虫,在第7、14、21、28天调查其成活率,研究转Bt水稻对青翅蚁形隐翅虫生长的影响。通过设置不同的猎物密度和捕食者密度,研究转Bt水稻对青翅蚁形隐翅虫成虫捕食功能的影响。【结果】室内条件下,转Bt水稻对青翅蚁形隐翅虫的存活率无明显影响。在试验褐飞虱密度下,转Bt基因水稻对青翅蚁形隐翅虫对褐飞虱的捕食量无显著影响,且捕食作用方程可用HollingⅡ模型拟合,理论方程为Na=1.3421N/(1+0.0887N)。瞬时攻击率a′和平均处理时间Th无显著差异,同时,转Bt基因水稻对青翅蚁形隐翅虫的捕食干扰反应无显著影响。【结论】转Bt基因水稻对供试天敌昆虫青翅蚁形隐翅虫存活率和捕食功能无明显影响。     

青翅蚁形隐翅虫的研究

青翅蚁形隐翅虫在福州稻田一年约发生五代,世代重叠。世代历期气温28～30℃为39～42天;24～26℃为50～53天;20～23℃为59～67天。冬季以成虫在田边杂草、紫云英田、板田稻柱和再生稻等处越冬。早、晚稻田分别于5～6月、6～7月、8月上中旬、9月中下旬和10月上中旬共出现五次高峰期。在稻田能捕食多种害虫,喜食稻飞虱、稻叶蝉等小型虫类。农药杀虫双、其次是敌敌畏对青翅蚁形隐翅虫成虫较为安全。     

稻田主要天敌对害虫的捕食作用

应用二次正交旋转组合设计方法建立3种天敌、2种害虫共存情况下白背飞虱被捕食数量与5个因素相互关系的数学模型。结果表明,3种天敌对白背飞虱被捕食量影响的大小排序为拟水狼蛛>青翅蚁形隐虫>食虫沟瘤蛛,食虫沟瘤蛛与拟水狼蛛、拟水狼蛛与青翅蚁形隐翅虫有负交互作用。     

青翅蚁形隐翅虫对稻纵卷叶螟和白背飞虱的捕食作用

应用二次回归正交设计建立青翅蚁形隐翅虫对稻纵卷叶螟和白背飞虱捕食作用的数学模型分别为：Y＇cm=3.5072＋1.6671x1＋1.7200x2-1.004x3＋0.6375x1x2-0.7625x1x3-0.2625x2x3＋0.6020x^21-0.3538x^22-0.0807x^23;Y＇sf=3.7612＋0.4015x1＋0.2573x2＋1.6645x3＋0.1250x1x3＋x2x3＋0.3372x^21-0.4820x^22＋0.0641x^23.结果表明,青翅蚁形隐翅虫对白背飞虱表现出更强的取食选择性.当猎物密度较低时,青翅蚁形隐翅虫对稻纵卷叶螟的捕食作用为密度制约性,当猎物密度较高时,青翅隐翅虫对白背飞虱的捕食作用为密度制约性.     

用ELISA方法研究稻田节肢动物的食物关系

应用酶联免疫吸附试验双抗体夹心法,研究了稻田节肢动物,包括19种捕食性天敌、4种主要水稻害虫及1种中性昆虫之间的食物关系。在检测的19种捕食者中,有15种捕食了白背飞虱,11种捕食了褐飞虱。其中食虫沟瘤蛛、拟水狼蛛、八斑鞘蛛、粽管巢蛛、四斑锯螯蛛和拟环纹豹蛛对两种稻飞虱的捕食阳性率较高。有7种捕食了稻纵卷叶螟幼虫,其中粽管巢蛛、褶管巢蛛、拟环纹豹蛛、青翅蚁形隐翅虫和印度细颈步甲的捕食阳性率较高。拟环纹豹蛛、浙江豹蛛和拟水狼蛛对稻蝗若虫有较高的阳性率。13种捕食者捕食了摇蚊,摇蚊作为替代或补充猎物,对稻田捕食性节肢动物亚群落的重建和发展具有重要意义。在实验检测的基础上,构建了被检测节肢动物猎物与捕食者间的食物关系图。     

蚁巢表层土壤温湿度对不同发育阶段红火蚁数量的影响(英文)

红火蚁一种攻击性非常强的外来入侵蚂蚁,可对入侵地的农业生产、生态系统、人体健康和公共安全等产生负面影响,温度和湿度是影响其生长和发育的重要环境因子.本研究评估了红火蚁蚁巢表层土壤温、湿度对红火蚁幼虫、有翅蚁蛹和有翅蚁成虫数量的影响.结果表明,随着土壤温度的升高,幼虫、有翅蚁蛹和有翅蚁成虫的数量都呈先升高后下降的趋势.当温度为26～30℃时,幼虫数量达到最大值,而当温度为20～25℃时,有翅蚁蛹和有翅蚁成虫数量达到最大值.当温度<20℃时,有翅蚁成虫和幼虫的数量均与土壤相对湿度呈负相关,但是有翅蚁雌雄蛹的数量都与相对湿度呈正相关.当温度<20℃时,在相对湿度为41％ ～50％时,雄性有翅蚁的数量达到最大值,在相对湿度为71％ ～80％时,有翅蚁蛹的数量达到最大值.本研究将对防治这种危险的入侵害虫提供理论依据.     

微红梢斑螟蛀道节肢动物种群结构及生态位

选择我国江苏、安徽和广东7个不同林型的松树林地,对微红梢斑螟(Dioryctria rubella)蛀道节肢动物种群结构及生态位进行调查研究。结果表明:微红梢斑螟蛀道节肢动物种群隶属2纲9目13科,分别为蛛形纲蜘蛛目、蜱螨目,昆虫纲弹尾目、革翅目、啮虫目、半翅目、缨翅目、鞘翅目、膜翅目;利用相对优势指标判别微红梢斑螟蛀道节肢动物优势种有螨科和隐翅虫科,丰盛种有跳虫科,常见种有啮虫科、蠼螋科、蚁科、锯谷盗科、象甲科、蓟马科和茧蜂科,偶见种有小蠹科、蝽科和微蛛科;利用Levins生态位宽度和Pianka生态位重叠对各种群生态位计算表明,隐翅虫科与微红梢斑螟的时间和空间生态位重叠值最大,说明在各种群中隐翅虫科与微红梢斑螟的跟随关系最为紧密;利用聚集度指标法判别优势种群隐翅虫的空间分布属于聚集型分布,用零频率方法计算隐翅虫种群的空间格局为聚集型,种群类型为聚集度逆零频率制约型。     

稻田主要捕食性天敌的栖境生态位与捕食作用分析

本文进行了稻田捕食性天敌与稻飞虱的栖境生态位调查,并应用正交试验设计、添加试验法和排除试验法研究了?物种的栖境生态位与各天敌捕食作用的关系,结果表明：在5种灭敌与2种害虫共存系统中,天敌对褐飞虱Nilaparvata lugens Stal捕食量的正主效应大小依次为： 粽管巢蛛 Clubiona aponicola、青翅蚁形隐翅虫Paederus fuscipes、前齿肖蛸Tetragnatha praedonia、食虫沟瘤蛛 Ummeliata insecticeps,拟水狼蛛Pirata subpiraticus的负主效应值最大(随狼蛛密度增大捕食量下降);对稻纵卷叶螟Cnaphlocrcis medinalis Guenee捕食量正主效应大小依次为： 粽管巢蛛、肖蛸、青翅蚁形隐翊虫。多物种共存系统中,狼蛛、微蛛、跳蛛主要捕食飞虱;肖蛸主要捕食稻纵卷叶螟;管巢蛛对两种害虫均具有较好的控制作用。这与各物种的生态位宽度值相一致。当飞虱密度在每穴10一30头时,多物种共存系统优良的生物序是拟水狼蛛、食虫瘤胸蛛、青翅蚁形隐翅虫各为l头,棕管巢蛛2头,此时天敌的控制作用最大。添加法和排除法试验结果表明在具-定数量的多物种共存系统中,再增加天敌密度不一定能增加猎物的被捕食数,其直接的生物学原因是种间种内干扰(包括种间种内残杀)     

锈翅蚁蛉(脉翅目:蚁蛉科)的发育生物学研究

锈翅蚁蛉为全变态类昆虫,在贵州省一年发生1代,11月下旬开始越冬,各龄幼虫均可越冬,次年3月苏醒.在室内饲养条件下,卵期13 d±0.56 d,幼虫期63.58 d±1.81d,蛹期26.35 d±1.14 d,成虫期20 d± 1.06 d.结合野外调查和室内饲养,详细描述了锈翅蚁蛉各虫态的形态特征,幼虫的筑穴、捕食、蜕皮、化蛹、羽化以及成虫的捕食、交配等行为习性.     

昆明红火蚁种群发生特征

【目的】2013年10月云南省元谋县首次发现红火蚁。掌握红火蚁蚁巢各品级发生动态,能为当地红火蚁的防控提供技术支撑。【方法】2015年1—12月,在昆明宜良县对红火蚁蚁巢取样、分离,红火蚁取样、称重,统计红火蚁各品级的头数。【结果】地上蚁巢红火蚁蚁群数量发生高峰期在8—9月,其次是3—4月。蚁后数量比例高峰在3—4月;有翅雌蚁比例高峰在4月,其次是7月;有翅雄蚁比例高峰的在5月,其次是9月;生殖蚁幼虫和蛹比例高峰的3、4和12月。地上蚁巢工蚁、兵蚁、职能蚁幼虫和蛹数量发生的高峰期在8—9月,发生小高峰期在4月。【结论】昆明红火蚁蚁群数量动态有2个峰值,第一个峰值为8—9月,以职能蚁防治为主;第二个蜂值3—4月,以生殖蚁和职能蚁防治为主。该结果为昆明红火蚁防控技术提供了数据支撑。     

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.     

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.     

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.