双斑长跗萤叶甲在玉米田的种群消长规律

【目的】明确双斑长跗萤叶甲Monolepta hieroglyphica(Motschulsky)的发生规律,为双斑长跗萤叶甲的预测预报和综合治理提供科学依据。【方法】2011年通过田间系统调查对山西省忻州市和晋中市玉米田的双斑长跗萤叶甲的种群消长动态进行了系统研究。【结果】在山西省忻州市的玉米田,越冬卵在5月下旬开始孵化,幼虫以玉米根系为食,6月中旬为幼虫的发生高峰期,部分老熟幼虫开始化蛹,6月下旬成虫开始羽化出土,为害玉米叶片,8月初成虫种群数量达到最高峰,8月中旬以后随着玉米花丝大部分萎蔫,叶片开始衰老,玉米田间的成虫种群数量也急剧下降。10月中旬玉米田成虫基本消失,但是在杂草上还能发现少量的成虫。在山西省晋中市,玉米的生育期比忻州市晚10 d左右,双斑长跗萤叶甲的发生期也相对晚一些,但是种群数量的发生发展趋势基本是一样的。双斑长跗萤叶甲成虫在靠近杂草的玉米田边比在玉米田中部的发生更重,而在成虫的发生高峰期,田边和田中间的种群密度无显著性差异。【结论】双斑长跗萤叶甲在山西省1年发生1代,在山西省忻州市的发生期比晋中市的要早10 d左右,这与两地玉米田的不同的土壤性质、灌溉方式、玉米生育期等因素有关。     

蠋敌对双斑长跗萤叶甲成虫的捕食功能研究

在室内研究了捕食性天敌蠋敌对双斑长跗萤叶甲成虫的捕食功能反应.结果表明,蠋敌对双斑长跗萤叶甲成虫的捕食功能符合HollingⅡ模型,日最大捕食量为20.4头双斑长跗萤叶甲成虫,捕食一头双斑长跗萤叶甲成虫需要2.94min,功能系数为0.5169;蠋敌成虫个体间相互干扰对捕食效应的影响可以用E=0.4046*P-0.3914模拟;蠋敌若虫对自身密度的功能反应可以用A=0.3034p-0.5357模拟.经卡方检验,其理论值与实测值无统计学差异.     

高温胁迫对双斑长跗萤叶甲成虫总蛋白和两种保护酶的影响

双斑长跗萤叶甲是新疆北疆棉花的主要害虫之一。本研究旨在探索短时高温对双斑长跗萤叶甲成虫生理生化的影响。在室内研究了不同高温(33℃、37℃、41℃、45℃)不同时间(0.5 h、1.5 h、2.5 h、6 h、12 h)处理后,双斑长跗萤叶甲成虫体内总蛋白含量、过氧化物酶(POD)及过氧氢酶(CAT)的变化规律。双斑长跗萤叶甲成虫总蛋白在37℃处理12 h时,蛋白含量最高,41℃处理12 h时有所下降,45℃时双斑长跗萤叶甲只能存活1.5 h,但蛋白含量仍高于对照(26℃)。POD活性随温度升高先升高后降低。在33℃处理6 h时,活性最高,在41℃处理12 h时,活性最低。CAT活性在同一时间不同温度处理中呈先降后升再降趋势。在37℃处理1.5 h时活性达到最高,在41℃处理12 h时活性最低。在同一温度不同处理时间中,CAT活性在33℃时先升高后降低,在37℃、41℃时随时间的延长先升高后降低,在45℃时持续降低,且显著低于对照(26℃)。双斑长跗萤叶甲总蛋白及保护酶的活性与温度密切相关,据此推测高温下双斑长跗萤叶甲成虫死亡的原因与保护酶系统被破坏有关。     

中国南方双斑长跗萤叶甲地理种群遗传结构及Wolbachia感染

[目的]双斑长跗萤叶甲Monolepta hieroglyphica为多食性害虫,可取食为害多种农作物.本研究旨在探究中国南方地区分布的双斑长跗萤叶甲地理种群的遗传多样性、遗传结构及种群间的遗传分化程度与基因流水平,探究共生菌Wolbachia 在中国南方双斑长跗萤叶甲地理种群中的多样性和感染情况.[方法]以线粒体CO...     

封面照片

正照片示双斑长跗萤叶甲Monolepta hieroglyphica (鞘翅目:叶甲科)成虫在玉米Zea mays (禾本科)花丝上群聚取食。双斑长跗萤叶甲主要以成虫在玉米叶片、花丝及幼嫩籽粒,特别是取食咬断玉米花丝,甚至把花丝咬食光,导致玉米不能正常授粉灌浆或授粉推迟,影响结实和灌浆,咬食子粒诱发玉米穗腐病的发生,严重影响玉米的产量和品质。本期报道了中国南方双斑长跗萤叶甲地理种群遗传结构及Wolbachia感染研究(pp. 730-742)。本照片由王振营于2012年9月摄于黑龙江291农场。     

内蒙古荒漠草原亚洲小车蝗的种群动态

2010—2011年于内蒙古乌兰察布市四子王旗格根塔拉草原对亚洲小车蝗Oedaleus asiaticus(B.-Bienko)种群动态进行了研究。结果表明,亚洲小车蝗种群空间格局为随机分布;亚洲小车蝗于6月中旬开始孵化出土,1～3龄蝗蝻高峰期在6月中下旬至7月初,终见期在7月下旬;4～5龄蝗蝻于6月下旬始见,高峰期在7月上中旬,终见期在7月末;成虫于7月上旬始见,高峰期在7月中旬至8月下旬,终见期在9月上旬。应用最优分割法将亚洲小车蝗种群动态划分为3个阶段:(1)6月中旬,为蝗蝻开始出土期,数量稀少,空间格局为聚集分布或随机分布;(2)6月下旬至7月上中旬,为蝗蝻发生盛期,密度低时为随机分布,密度高时为聚集分布;(3)7月中下旬至9月上旬,为成虫发生期,空间格局为随机分布。     

中国东北地区大豆主要食叶性害虫种类分析

2005～2007年,对大豆食叶性害虫种类开展了系统调查。共发现5目、15科、29种害虫。大豆蚜Aphisglycines Matsumura、茄无网长管蚜Acythosiphon solani(Kaltenbach)、豆黄蓟马Thrips nigropilosus Uzel、二条叶甲成虫Monolepta nigrobilineata(Motsch.)、双斑萤叶甲成虫Monolepta hieroglyphica(Motsch.)、大造桥虫Ascotis selenaria Schiffermüller et Denis幼虫及豆卜馍夜蛾Bomolocha tristalis Lederer幼虫为主要食叶性害虫。其中,大豆蚜、茄无网长管蚜田间发生较早,6月上旬已有发生;大造桥虫幼虫、豆卜馍夜蛾幼虫发生较晚,6月下旬后田间始见发生。豆黄蓟马成虫危害期为6月上旬至9月上旬,若虫危害期为6月中旬至8月下旬。二条叶甲成虫的危害期为6月上旬至9月下旬,双斑萤叶甲成虫发生期为7月上旬至9月上旬。     

甘南地区小红珠绢蝶生物学特性研究初报

小红珠绢蝶Parnassius nomion Fischer von Waldheim在甘肃甘南1年发生1代。翌年5月上旬幼虫孵化,6月下旬开始化蛹,7月下旬至8月上旬,成虫开始羽化,8月中旬至9月上旬成虫开始产卵,该虫以卵越冬。     

西藏飞蝗的生物学特性

西藏飞蝗Locusta.migratoria tibetensis Chen在四川甘孜州1年发生1代,某些地方(乡城县)1年发生不完整的2代,即以卵越冬,翌年3月下旬开始孵化出土,4月中、下旬为孵化盛期,1~3龄始盛期为4月中旬~5月中旬,高峰期为5月下旬,7月上旬初始羽化,7月下旬~8月上旬为羽化盛期,8月上旬始见产卵,8月下旬~9月上旬为产卵盛期,第1代成虫较早产下的卵块在条件适宜的情况下可于当年9月上旬孵化出土,但孵化出的蝗蝻不能越冬。该虫卵、全蝻期及全世代的发育起点温度分别为14.2,16.1,14.6℃,有效积温为179.1日.度、360.0日.度、787.8日.度。在18,21,24,27和30℃等5种恒温条件下其平均世代历期214.4,133.3,79.2,66.3和50.7d。     

双斑长跗萤叶甲触角感器的扫描电镜观察

利用扫描电镜观察了双斑长跗萤叶甲Monolepta hieroglyphica(Motschulsky)成虫触角及其感器的形态与分布。结果表明:双斑长跗萤叶甲成虫触角为线状,由柄节、梗节和鞭节组成,鞭节有9节,其中,雄虫的触角比雌虫长;感器类型有毛形感器(1型、2型和3型)、刺形感器、锥形感器(1型和2型)、腔锥形感器、Bhm氏鬃毛、钟形感器共9种。雌雄成虫触角感器类型无差异,但雄虫触角上的感器分布要比雌虫的稠密。     

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.