蝗虫微孢子虫病在草原蝗虫优势种种群及空间的分布

在采用蝗虫微孢子虫Nosema locustae防治过的草场中进行抽样调查,研究了草原蝗虫优势种类、混合种群平均密度与蝗虫微孢子虫疾病分布之关系,以及该疾病的空间分布。在防治后的当年,蝗虫微孢子虫疾病的感染率随着混合种群平均密度及靶标蝗虫亚洲小车蝗Oedaleus asiaticus的感病率的下降而降低。但是,次靶标蝗虫如宽须蚁蝗Myrmeleotettixpalpalis(一种中后期发生的种类)其感病率呈上升趋势,表明该疾病可在不同发生期种类蝗虫之间进行有效地传播。病蝗虫在防治后第7d其空间分布呈随机分布(Poisson),第28d 则是聚集分布,第40d时也呈聚集分布。于1993年、1994年对1988年(样区Ⅱ)、1989 年(样区Ⅲ)采用微孢子虫防治过的草场进行抽样调查。结果表明,在二个样区中,二年混合种群平均虫口密度与混合种群的平均感病率呈正相关(相关系数分别为r=0.289, r=0.479)。蝗虫微孢子虫病在主要优势种,如亚洲小车蝗、宽须蚁蝗、白边痂蝗Bryode maluctuosumluctuosum、皱膝蝗Angaracris /I>spp.、毛足棒角蝗Dasyhippus barbipes均有分布。二个样区中的混合蝗虫种群的平均感病率在1994年显著低于1993年。混合蝗虫种群的种类组成也有所变化,与1993年相比,1994年宽须蚁蝗及白边痂蝗的比例上升较大,而亚洲小车蝗的比例下降。经过5—7年的扩散,蝗虫微孢子虫病至少可扩散距防治区1 000m,其扩散方向可能与风及地势等有关。     

微孢子虫和狄斯瓦螨分别侵染后的意蜂血淋巴蛋白质含量变化

微孢子虫Nosema apis和狄斯瓦螨微孢子虫Nosema apis和狄斯瓦螨 Varroa destructor (Acari: Varroidae)均为危害意蜂Apis mellifera的重要寄生虫,该文对其危害后意蜂血淋巴蛋白质含量的变化进行了研究。用考马斯亮蓝法测定了意蜂受侵染后血淋巴的蛋白质总量,并用高压超薄层等电点聚焦法进行血淋巴蛋白质分类。结果显示,病蜂血淋巴蛋白质总量,在人工感染微孢子虫后1～10天呈微孢子虫Nosema apis和狄斯瓦螨 Varroa destructor (Acari: Varroidae)均为危害意蜂Apis mellifera的重要寄生虫,该文对其危害后意蜂血淋巴蛋白质含量的变化进行了研究。用考马斯亮蓝法测定了意蜂受侵染后血淋巴的蛋白质总量,并用高压超薄层等电点聚焦法进行血淋巴蛋白质分类。结果显示,病蜂血淋巴蛋白质总量,在人工感染微孢子虫后1～10天呈上升趋势,然后逐渐下降,感染后12～27天保持在感染前意蜂血淋巴总蛋白质含量水平以下。螨侵染后意蜂血淋巴蛋白质含量明显增高,与健康意蜂相比差异极显著。高压超薄层等电点聚焦分析表明：狄斯瓦螨自然侵染意蜂后,意蜂血淋巴蛋白质组分与健康对照组相比发生了明显改变。这些结果提示,意蜂对于微孢子虫或狄斯瓦螨的侵染产生了一定的免疫反应。     

蝗虫微孢子虫对东亚飞蝗卵黄原蛋白含量的影响

采用免疫学方法,对东亚飞蝗Locusta migratoria manilensis感染蝗虫微孢子虫Nosema locustae后体内卵黄蛋白含量的变化进行了研究。结果表明,感病蝗虫与对照健虫相比,卵黄发生有严重障碍,脂肪体和卵巢中卵黄原蛋白或卵黄蛋白含量极低,导致感病雌虫丧失产卵能力。脂肪体中卵黄原蛋白含量最高峰健虫为18.7 mg/mL,而病虫只有4.7 mg/mL;血淋巴中卵黄原蛋白含量最高峰健虫为7.6 mg/mL,而病虫只有2.6 mg/mL;卵巢中卵黄蛋白含量最高峰健虫为73.4 mg/mL,而病虫只有4.9 mg/mL。     

蝗虫微孢子虫病对东亚飞蝗聚集行为的影响

采用行为生测法和触角电位法研究了感染蝗虫微孢子虫病的东亚飞蝗对其聚集信息素粗提物的行为反应。在第3龄时部分蝗虫每头接种10^6个蝗虫微孢子虫,与健虫同一条件下饲养。用二氯甲烷从健康蝗虫的粪便、体表或卵囊中抽提聚集信息素,粗提物经纯化和浓缩后保存于冰柜中待用。结果表明,感病飞蝗对其信息素的感受能力下降,聚集行为反应减弱。行为生物测定发现,微孢子虫病对第4龄雌性蝗虫和第5龄蝗虫的聚集行为有明显的抑制作用,而对第4龄雄蝗的影响较小;总的看来,信息素粗提物对感病雄蝗和高龄蝗虫的作用分别高于对感病雌蝗和低龄蝗虫的作用。触角电位(EAG)测定表明,感染了微孢子虫病的东亚飞蝗蝗蝻和成虫,对其信息素粗提物的敏感性降低,且对不同来源的聚集信息素的电生理反应不同,其中对从雄性成熟蝗虫、第4龄蝗蝻及第5龄病虫的粪便中抽提制备的信息素粗提物、第4龄蝗蝻粪便挥发物、第4龄蝗蝻活虫体表挥发物的电生理反应显著下降;但对第5龄雌蝗和第5龄散居型蝗虫的粪便抽提物的电生理活性,病健虫无明显差异。此研究结果证明,施用微孢子虫治蝗时,微孢子虫对蝗虫的聚集行为有明显的影响,为微孢子虫的控害机理提供了新的证据。     

蝗虫微孢子虫的生产及田间应用现状

蝗虫微孢子虫是国际上商品化的微孢子虫杀虫剂,在对蝗虫的生物防治方面具有重要作用。介绍了关于蝗虫微孢子虫的基础理论知识、大规模生产技术及田间应用现状,同时对利用蝗虫微孢子虫进行害虫生物防治提出了一些有益的建议。     

蝗虫微孢子虫对东亚飞蝗的实验感染

蝗虫微孢子虫(Nosema locustae Canning)系Canning(1953,1962)从非洲飞蝗(Locustamigratoria migratorioides)体内分离并命名。Henry(1971、1973)用双带蚱蜢(Melanoplus bivittatus)做替代寄主增殖孢子,用来防治草原蝗虫取得显著成效,后来发展成为第一个商品化的微孢子杀虫剂。 1985年我们从美国John.S.Evans博士处得到蝗虫微孢子虫浓缩液,并成功地在东亚飞蝗体内增殖,从而获得大量孢子。本文报道经东亚飞蝗体内增殖后的孢子超微形态结构、发育过程及孢子产生等方面的观察结果。     

蝗虫微孢子虫及其在蝗害治理中的作用

扼要阐述了蝗虫微孢子虫的生活史、形态特征及其防治蝗虫的原理和方法。指出,用蝗虫微孢子虫治蝗具有显著的社会、经济及生态效益。     

蝗虫微孢子虫及其在蝗害治疗中的作用

扼要阐述了蝗虫微孢子虫的生活史,形态特征及其防治蝗虫的原理和方法。指出用蝗虫微孢子虫治蝗具有显著的社会,经济及生态效益。     

九种蝗虫核型似近系数的聚类分析研究

应用核型似近系数聚类分析方法,研究了小稻蝗Oxya hyla intricata、山稻蝗O.Agav-isa、上海稻蝗O.Shanghaiensis无齿稻蝗O.Adentata、中华稻蝗O.Chisensis、日本稻蝗O.Japonica、短额负蝗Atractomorpha sinensis、奇异负蝗A.Pergrina和日本蚱Tetrix japonica等9种蝗虫的亲缘关系。结果显示,9种蝗虫分为3类：稻蝗,负蝗和蚱。6种稻蝗之间的核型似近系数(λ)在0.961～0.5695之间,2种负蝗的λ＝0.5867,日本蚱与这8种蝗虫的λ在0.5318～.0322。聚类图直观地反映出它们的亲缘关系与形态分类学的分类结果相一致。从9种蝗虫 的核型演化上看,日本蚱是较原始的类型,负蝗分化也较早,而稻蝗则是较进化的类型。     

Lipid storage and changes during flight by triatomine bugs (Rhodnius prolixus and Triatoma infestans)

Exceptionally large amounts of lipid are stored in flight muscles of Rhodnius prolixus and Triatoma infestans (197 and 90 μmoles glyceride glycerol per g fresh weight respectively). The bulk of this lipid is in the form of triacylglycerol.A significant decrease in the muscle lipid occurs during the first hour of flight. Over the same period there is an increase in haemolymph lipid (particularly of diacylglycerol) which is taken to indicate the use of lipid from the fat body. The carbohydrate content of muscle and haemolymph is low, so it is likely that the supply of energy for flight is provided almost exclusively by the oxidation of fat. Oleate and palmitate are the major fatty acid components of lipid from both Triatoma and Rhodnius and are probably also the major fatty acids used for oxidation.Maturation of flight ability is temporally associated with the development of flight muscle size and increase in glyceride content.     

Activation of triacylglycerol lipase in the fat body of a beetle by adipokinetic hormone

The activation of triacylglycerol lipase and the stimulation of proline synthesis in the fat body of the fruit beetle Pachnoda sinuata by the endogenous octapeptide hormone Melme-CC (pQLNYSPDWa), which belongs to the family of insect adipokinetic hormones, were studied, and the correlation of both events investigated. At rest, the activity of triacylglycerol lipase in the fat body of the beetle was higher than in the fat body of the American cockroach, Periplaneta americana, but lower than in the migratory locust, Locusta migratoria. Triacylglycerol lipase of the beetle is activated by: (a) injection of synthetic Melme-CC and (b) the stimulus of flight. Activation of lipase by Melme-CC is time-dependent. Injection of cpt-cAMP activates triacylglycerol lipase in the fat body and causes an increase in the concentration of proline in the haemolymph at the expense of alanine. In contrast, injection of F-inositol-1,4,5-phosphate does not affect the activation state of lipase, nor the levels of amino acids in the haemolymph. High doses of octopamine do not activate lipase. Furthermore, activity of fat body lipase and proline concentration in the haemolymph both follow a circadian rhythm: both parameters are high in the morning, whereas they are low in the evening. When transfer of Melme-CC, released from the corpora cardiaca, to the thorax/abdomen is prevented by neck-ligation, the activity of lipase, as well as the circulating proline levels are low. Regression analysis revealed that activity of triacylglycerol lipase is positively correlated to proline concentration in the haemolymph, whereas there is a negative correlation of the enzyme activity and alanine level in the haemolymph. From these results we conclude that the activation of fat body triacylglycerol lipase by Melme-CC in P. sinuata stimulates proline synthesis. Proline is one of the major substrates to power flight activity in the beetle.     

Wing morph-related physiological differences in adults of temperate population of Pyrrhocoris apterus (L.) (Heteroptera: Pyrrhocoridae)

The reproductive and diapausing adult females of brachypterous morph and macropterous females with reproductive arrest of non-diapause type, originating from the laboratory cultures of Pyrrhocoris apterus, were studied for their feeding and drinking behaviour, digestive enzyme activities, and carbohydrate and lipid contents. The highest feeding and drinking activities were observed in reproductive brachypters, the lowest in macropters. Macropters also differed from brachypters by lower activities of gut lipase, peptidase and protease, lower concentration of haemolymph sugars, and lower weight of fat body, which probably reflects their low feeding activity. The total content of fat body lipids was also lower in macropters (0.6 mg) than in reproductive and diapausing brachypters (4.6 and 7.5 mg, respectively) on day 14. A very high amount of glycogen was found in the fat body of diapausing brachypters, 363 μg on day 14, as opposed to 15 and 80 μg in macropterous and reproductive brachypterous females, respectively. The obtained data indicate that the most important difference between macropterous and brachypterous females with different types of reproductive arrest consists of an enhanced mobilization of lipids for dispersal in macropters and accumulation of energetic reserves for hibernation in brachypters.     

大斑芫菁滞育幼虫在滞育不同阶段体内糖类和醇类含量的变化

在以卵滞育的昆虫中昆虫滞育时的生理代谢特点已经得到了大量研究。本文对以末龄幼虫（5龄）滞育的大斑芫菁Mylabris phalerate（Pallas）在不同滞育阶段体内糖类和醇类代谢的特征进行了研究。结果表明： 滞育个体血淋巴中的海藻糖含量高于非滞育个体,且随滞育时间的加大逐渐升高,滞育5个月时达到最大值,为5.61 μmol/mL。糖原的含量随滞育的进程逐渐减少,滞育初期（0.5个月）为0.72 mg/mL,到滞育末期（5个月）时仅为0.1 mg/mL。滞育个体脂肪体中的海藻糖含量都高于非滞育个体,滞育1个月时为非滞育个体的3倍,至滞育末期时达非滞育个体的5倍,为2.5 μmol/g脂肪体。糖原含量总体变化趋势是随滞育时间的加大逐渐减少,滞育早期和中期都高于非滞育个体。在滞育过程中血淋巴积累的小分子多元醇主要为甘油,其次是山梨醇;而在脂肪体中主要为甘油,其次是甘露醇,少量积累山梨醇：表明大斑芫菁滞育幼虫主要积累的是海藻糖和一些小分子多元醇。滞育幼虫在准备滞育时储备了大量糖原,这些糖原可能为滞育期间海藻糖、山梨醇和甘油的代谢提供了原料。     

Endocrine control of TAG lipase in the fat body of the migratory locust, Locusta migratoria

Aspects of the role and activation of the enzyme triacylglycerol lipase (TAG lipase) in the fat body of the migratory locust Locusta migratoria were investigated. TAG lipase is under the hormonal control of the three endogenous adipokinetic peptides of the migratory locust, Locmi-AKH-I, Locmi-AKH-II and Locmi-AKH-III. Injection of low doses (5-10 pmol) of each peptide causes an increase in lipase activity. The activation of lipase is time dependent: an elevated activity was recorded 15 min after injection of 10 pmol Locmi-AKH-I and maximum activation was reached after 45-60 min. The activation of TAG lipase is also dose-dependent. Doses of 2 pmol of each Locmi-AKH had no effect, whereas 5 pmol caused a significant activation. Maximum activation is reached with a dose of 10 pmol. Analogues of the second messengers cAMP (cpt-cAMP) and IP(3) (F-IP(3)) both activate the enzyme glycogen phosphorylase whereas only cpt-cAMP, but not F-IP(3), activates TAG lipase; cpt-cAMP elevates the lipid levels in the haemolymph. Activation of lipase is specific to the three endogenous AKH peptides: 5 pmol of the endogenous peptide Locmi-HrTH and 10 pmol of corazonin failed to activate lipase. High doses of octopamine did not activate lipase nor did they elevate the lipid concentration in the haemolymph. TAG lipase is stimulated by flight activity but activation is slower than that of glycogen phosphorylase: after 30 min of flight or after 5 min of flight plus 1h of subsequent rest, activity of TAG lipase is increased, but not immediately after 5 min of flight. In contrast, glycogen phosphorylase is activated significantly after 5 min of flight. These activation patterns of the two enzymes mirror-image the concentration of their substrates in the haemolymph: there is a significant decrease in the concentration of carbohydrates after 5 min of flight, whereas no change of the concentration of lipids can be measured after such short time of flight activity; however, a subsequent rest period of 1h is sufficient to increase the lipid concentration.     

龟纹瓢虫卵黄蛋白的分子特性及发生动态

研究了龟纹瓢虫Propylea japonica (Thunberg) 卵黄蛋白的基本特性以及卵黄发生过程中卵黄蛋白的动态变化。PAGE和SDS-PAGE实验表明,龟纹瓢虫卵黄蛋白分子量为294.81±40.70 kD,并由分子量分别为144.68±0.03 kD和51.23±0.27 kD的两种亚基组成。对卵黄蛋白的氨基酸组成和含量分析发现,其必需氨基酸总量占57.48％,略高于非必需氨基酸,其中谷氨酸（Glu）含量最高,为15.26％;色氨酸（Trp）和蛋氨酸（Met）含量较低,分别为0.50％和0.11％。采用间接竞争ELISA法,系统测定了龟纹瓢虫成虫期脂肪体、血淋巴和卵巢中卵黄蛋白的动态变化,结果表明：脂肪体是卵黄原蛋白合成的场所,卵黄原蛋白的合成始于羽化后第2天;脂肪体、血淋巴和卵巢中卵黄原蛋白的滴度在羽化后第4天开始迅速上升,至成虫期的第8天左右达到高峰期。     

家蚕感染蛹虫草后的生理生化变化

蛹虫草分生孢子侵染5龄家蚕Bombyx mori后,家蚕血淋巴中总糖、海藻糖、蛋白质和甘油酯含量均有不同程度的下降,其中甘油酯含量下降最为明显。海藻糖酶活性在侵染初期也明显降低。接种后家蚕体内的保护酶超氧化物歧化酶、过氧化物酶和过氧化氢酶活性也有较大变化,其中超氧化物歧化酶活性上升最为明显,在4日内由441.841 U/mL升至601.255 U/mL。     

Carbohydrate metabolism in the stick insect, Carausius morosus

Age-related changes in some parameters related to carbohydrate metabolism in the stick insect, Carausius morosus, were investigated during the 6th instar and up to day 37 of adult life. Total haemolymph carbohydrate concentration and the fat body glycogen content are low and may be related to the low activity of this insect. Trehalose constitutes about 75–80% of the total blood carbohydrate pool. During the moult, total blood carbohydrate, fat body glycogen and haemolymph volume, decrease while glycogen phosphorylase activity of the fat body is slightly activated. The effects are brought about mainly by reduced feeding activity, but may also be influenced by the shedding and replacement of the cuticle. During starvation, blood homeostasis is maintained at the expense of fat body glycogen via an activation of phosphorylase. During reproduction, although no dramatic changes in fat body glycogen levels occur, blood carbohydrates are maintained and fat body phosphorylase is slightly activated. The possibility is discussed that during moulting and reproduction, blood sugar homeostasis is maintained by a hormonal mechanism controlling glycogen phosphorylase. No circadian rhythm in any parameter investigated is observed.     

Specificity and localisation of lipoprotein lipase in the flight muscles of Locusta migratoria

Using natural lipoproteins as substrates, lipase activity has been measured in leg muscle, fat body, midgut and flight muscles of Locusta migratoria. The enzymic activity in the flight muscles is higher than in those other tissues tested, confirming the potential of the flight muscles to utilise lipids at high rates. In addition, a membrane-bound lipoprotein lipase can be extracted from flight muscle. The flight muscle enzyme activity shows a marked substrate specificity; at lipoprotein concentrations equivalent to those found normally in flown or resting locusts respectively, the enzyme hydrolyses diacylglycerols associated with lipoprotein A+ (present in the haemolymph of flown or adipokinetic hormone-injected locusts) at about 4 times the rate of those associated with lipoprotein Ayellow (which is the major lipoprotein in resting locusts). In addition, the hydrolysis of lipids carried by lipoprotein Ayellow is dramatically reduced in the presence of lipoprotein A+. These observations indicate that the enzyme plays a specific role in the uptake of lipids at the flight muscles to ensure a smooth transition from carbohydrate to lipid based metabolism during flight.     

The neuro-endocrine control of protein metabolism in the migratory grasshopper, Melanoplus sanguinipes

In normal females, distinct fluctuations in the protein content of the fat body and haemolymph are evident during each gonotrophic period. These fluctuations partly reflect changes in the protein requirements of the developing oocytes. Almost one half of the total protein deposited in the mature ovary is sequestered during the final stages of vitellogenesis when protein accumulated in the fat body and haemolymph is rapidly depleted. Although similar amounts of protein are deposited in the ovary during the first and subsequent gonotrophic periods, significantly less extraovarian protein is present throughout the latter periods.The accumulation of large amounts of protein in the fat body and haemolymph of ovariectomized females suggests that most yolk protein is of extraovarian origin. As the total protein content of these insects is comparable to that of vitellogenic females, ovariectomy apparently has no immediate effect on protein synthesis.Allatectomy or cautery of the median neurosecretory cells (mNSC) prevents vitellogenesis. Although protein gradually accumulates in the fat body and haemolymph of allatectomized females, the total protein content of these insects is significantly lower than that of controls. Treatment of allatectomized females with juvenile hormone analogue leads to a temporary but significant increase in the protein content of the fat body. However, the subsequent decline in fat body protein is paralleled by a pronounced increase in the protein content of the ovary. These findings suggest that the corpora allata (CA) stimulate both yolk protein synthesis in the fat body and its uptake into the ovary. The total protein content of mNSC-cauterized females is less than that of allatectomized females. This observation supports the proposal that the mNSC have not only an allatotropic effect but also a direct effect on protein synthesis.