桃园生草复合生态系统中桃蚜与草间小黑蛛种群的地统计学分析

利用地统计学原理和地理信息系统(GIS)分析了桃园生草模式下不同时期桃蚜Myzus persicae(Sulzer)种群和草间小黑蛛Erigonidium graminicola Sundevall种群的空间分布格局和空间相关性。结果表明,不同时期桃蚜和草间小黑蛛种群均存在较强的空间相关性,其理想的半变异函数曲线为高斯、圆型、指数或球型,其空间格局均呈聚集分布,变程范围分别为6.8630¹2.0903 m、6.863012.0903 m、6.8630¹2.6980 m,空间结构比例分别为0.011312.6980 m,空间结构比例分别为0.0113⁰.6546、0.06760.6546、0.0676⁰.6129,表明桃园生草模式下桃树草间小黑蛛对桃蚜在空间位置上具有追随关系,对其种群数量的控制有较大作用,草间小黑蛛是桃蚜的优势天敌。     

单季稻田的蜘蛛群落及与褐飞虱的相关性研究

通过对南京地区４种不同类型单季稻田蜘蛛群落的结构及其与褐飞虱的相关性研究,结果表明,该地区蜘蛛群落由１０科２１种组成,其中草间小黑蛛、食虫瘤胸蛛、拟水狼蛛为优势种。物种丰富度、多样性化防田低于生防田,而均匀性则施药田大于不施药田。不同移栽时间的稻田,丰富度、多样性、均匀性迟栽田低于早栽田。蜘蛛与褐飞虱各发育阶段的相关性分析表明,蜘蛛与褐飞属长翅成虫相关性好,而与低龄若虫相关性差;蜘蛛与褐飞虱的相关     

单季稻田的蜘蛛群落及其与褐飞虱的相关性研究

通过对南京地区４种不同类型单季稻田蜘蛛群落的结构及其与褐飞虱的相关性研究,结果表明,该地区蜘蛛群落由１０科２１种组成,其中草间小黑蛛、食虫瘤胸蛛、拟水狼蛛为优势种。物种丰富度、多样性化防田低于生防田,而均匀性则施药田大于不施药田。不同移栽时间的稻田,丰富度、多样性、均匀性迟栽田低于早栽田。蜘蛛与褐飞虱各发育阶段的相关性分析表明,蜘蛛与褐飞虱长翅成虫相关性好,而与低龄若虫相关性差;蜘蛛与褐飞虱的相关性主要由褐飞虱田间第１次若虫高峰时的蜘蛛量和蛛虱比决定,模拟的回归方程为：ｒ＝ － ０．１９９７＋ ０．００７５６ｘ１＋ ０．３３７１ｘ２（Ｆ＞ Ｆ０．０２３）。     

中稻田三种飞虱的捕食性天敌优势种及农药对天敌的影响

对两优0923非防治的中稻田白背飞虱、灰飞虱和褐飞虱与其天敌间的关系,采用灰色关联度法、生态位分析方法,对盆拍法调查的3种飞虱与其捕食性天敌在数量、时间和空间三方面关系进行分析,对每一种天敌对应的关联度、生态位重叠指数和相似性比例等参数标准化后的密切指数相加,按照密切指数值之和大小排序,评判3种飞虱捕食性天敌优势种.并用同样方法分析常规防治田农药对飞虱捕食性天敌的影响,以期为合理施药,科学保护和利用天敌优势种提供科学依据,其结果是,非防治田白背飞虱前三位天敌是条纹蝇虎、草间小黑蛛和锥腹肖蛸;灰飞虱的是八斑球腹蛛、茶色新园蛛和锥腹肖蛸;褐飞虱的是纵条蝇狮、四点亮腹蛛和黑肩绿盲蝽.防治田白背飞虱前三位天敌是条纹蝇虎、草间小黑蛛和锥腹肖蛸;灰飞虱的是拟水狼蛛、四点亮腹蛛和草间小黑蛛;褐飞虱的是黑肩绿盲蝽、拟水狼蛛和四点亮腹蛛.盆拍法的防治田和非防治田之间3种飞虱前三位的相同天敌,白背飞虱完全相同,灰飞虱没有相同天敌,褐飞虱的是黑肩绿盲蝽和四点亮腹蛛.飞虱与天敌在时间和数量关系上,扫网法的防治田和非防治田之间3种飞虱前三位的相同天敌,白背飞虱的是锥腹肖蛸和四点亮腹蛛,灰飞虱完全相同,褐飞虱的是纵条蝇狮和条纹影虎.两种稻田的差异主要是农药杀伤了飞虱,使飞虱数量减少,并对天敌有一定杀伤力,进而影响到天敌的发生规律.非防治田的盆拍法和扫网法之间,3种飞虱前三位相同的天敌,白背飞虱的是锥腹肖蛸,灰飞虱的也是锥腹肖蛸,褐飞虱的是纵条蝇狮.防治田两调查方法结果之间,白背飞虱的是锥腹肖蛸,灰飞虱和褐飞虱前3位天敌中没有相同天敌,其差异主要是两法调查稻株的部位不同所致.     

褐飞虱过氧化物酶基因NlPOD1的克隆、鉴定及功能分析

【目的】探明褐飞虱Nilaparvata lugens过氧化物酶基因NlPOD1的分子特性、表达模式和生物学功能。【方法】基于褐飞虱转录组数据,利用PCR技术克隆获得NlPOD1基因全长cDNA序列;利用生物信息学手段分析其序列特征;通过qRT-PCR技术检测NlPOD1在褐飞虱不同发育时期(卵、1-5龄若虫和初羽化雌雄成虫)和5龄若虫不同组织(头部、脂肪体、血淋巴和肠道)中的表达水平,以及不同微生物(大肠杆菌Escherichia coli、金黄色葡萄球菌Staphylococcus aureus和金龟子绿僵菌Metarhizium anisopliae)（1×10⁷/mL）注射感染褐飞虱5龄若虫不同时间后的诱导表达模式;利用RNAi技术沉默褐飞虱 5 龄若虫NlPOD1基因,并通过生物测定分析NlPOD1基因沉默和接种金龟子绿僵菌(1×108/mL)后褐飞虱的存活率及致死中时(LT₅₀)。【结果】获得褐飞虱NlPOD1全长 cDNA 序列(GenBank登录号: MZ682107),其开放阅读框长2 049 bp,编码682个氨基酸,含有一个典型的动物亚铁血红素过氧化物酶结构域(An_peroxidasedomain),且N端包含一段由29个氨基酸残基组成的信号肽。系统发育分析表明,NlPOD1与半翅目其他昆虫的POD亲缘关系较近,其中与茶翅蝽Halyomorpha halys POD亲缘关系最近。发育表达谱结果表明,NlPOD1在褐飞虱不同发育阶段均有表达,其中卵期表达量最低,5龄若虫中表达量最高;组织表达谱结果表明,NlPOD1在褐飞虱5龄若虫不同组织中均有表达,且肠道和血淋巴中的表达量显著高于头部和脂肪体中的;微生物诱导表达模式表明,与注射PBS的对照组相比,大肠杆菌诱导48 h内各时间点NlPOD1在褐飞虱5龄若虫中的表达量显著上调,而在金黄色葡萄球菌和金龟子绿僵菌诱导下,NlPOD1表达量均呈现先上调后回稳的态势。RNAi分析结果显示,显微注射dsNlPOD1可显著抑制NlPOD1的表达水平。通过RNAi抑制NlPOD1表达后褐飞虱5龄若虫存活率不变,但注射dsNlPOD1联合金龟子绿僵菌感染对褐飞虱5龄若虫的LT₅₀(4.5 d)显著低于注射dsGFP联合金龟子绿僵菌感染的对照组的LT₅₀(5.4 d),说明沉默NlPOD1后褐飞虱对金龟子绿僵菌侵染的抵御能力显著降低。【结论】NlPOD1在褐飞虱病原防御过程中发挥重要作用,可作为开发RNAi和病原真菌联合介导的褐飞虱防治技术中的一个潜在靶标。     

转Bt基因及其亲本水稻上褐飞虱对三唑磷和溴氰菊酯的反应

以转Bt基因抗虫水稻T1C-19(含cry1C基因)和T2A-1(含cry2A基因)及其亲本水稻MH63为材料,用20和40 mg·L^-1的三唑磷以及1、3和6 mg·L^-1的溴氰菊酯喷雾分别处理稻株上的3龄褐飞虱若虫,研究了两种农药对转Bt基因抗虫水稻上褐飞虱再猖獗的影响.结果表明： 三唑磷处理对褐飞虱的若虫历期无显著性影响,溴氰菊酯则能显著降低若虫历期,但随着两种药剂处理浓度的升高,若虫的存活率降低、成虫的产卵量增加.在同一浓度农药药剂处理下,3个水稻品种上的褐飞虱若虫发育历期、若虫存活率、初羽雌成虫体质量、产卵量和卵孵化率等生态学参数均没有显著差异.表明褐飞虱在两种转Bt水稻上对三唑磷和溴氰菊酯诱导再猖獗的反应能力与其亲本水稻MH63没有差异.     

CO2浓度倍增影响转Bt水稻非靶标害虫褐飞虱的生长发育及取食行为

近年来,大气CO₂浓度升高等全球气候变化和转Bt作物非靶标害虫抗虫性等问题备受关注.大气CO₂浓度升高直接或间接地影响植食性昆虫,而迄今为止有关大气CO₂浓度升高对刺吸式昆虫(同时也是转Bt作物的非靶标害虫)的影响结论不一,且对其刺吸取食行为的影响研究少有报道.本研究利用智能人工气候箱设置CO₂浓度,研究大气CO₂浓度倍增(800 μL·L^-1)对转Bt水稻的非靶标害虫褐飞虱取食行为及其生长发育和繁殖等的影响.结果表明: 大气CO₂浓度倍增对褐飞虱卵和若虫历期、成虫体质量和寿命,以及4龄和5龄若虫的刺吸取食行为等都具有显著影响,但对其繁殖力影响不显著.与对照CO₂浓度(400 μL·L^-1)相比,倍增CO₂浓度处理下褐飞虱的卵和若虫历期及雌成虫寿命分别显著缩短了4.0%、4.2%和6.6%;长翅型成虫比例显著增加了11.6%;初羽化成虫体质量降低,且雌成虫体质量显著降低了2.2%;此外,倍增CO₂浓度处理下褐飞虱4龄和5龄若虫口针的刺探效率都显著增加;其中,N4b波的持续时间分别显著延长了60.0%和50.1%,频次分别显著增加了230.0%和155.9%.可见,CO₂浓度倍增可通过提高褐飞虱的刺吸取食而促进其生长发育,并缩短其世代历期、提高长翅成虫比例,最终导致大气CO₂浓度升高下转Bt水稻的非靶标害虫褐飞虱发生危害严重,并面临其迁飞扩散为害加重的风险.     

CO2浓度倍增影响转Bt水稻非靶标害虫褐飞虱的生长发育及取食行为

近年来,大气CO₂浓度升高等全球气候变化和转Bt作物非靶标害虫抗虫性等问题备受关注.大气CO₂浓度升高直接或间接地影响植食性昆虫,而迄今为止有关大气CO₂浓度升高对刺吸式昆虫(同时也是转Bt作物的非靶标害虫)的影响结论不一,且对其刺吸取食行为的影响研究少有报道.本研究利用智能人工气候箱设置CO₂浓度,研究大气CO₂浓度倍增(800 μL·L^-1)对转Bt水稻的非靶标害虫褐飞虱取食行为及其生长发育和繁殖等的影响.结果表明: 大气CO₂浓度倍增对褐飞虱卵和若虫历期、成虫体质量和寿命,以及4龄和5龄若虫的刺吸取食行为等都具有显著影响,但对其繁殖力影响不显著.与对照CO₂浓度(400 μL·L^-1)相比,倍增CO₂浓度处理下褐飞虱的卵和若虫历期及雌成虫寿命分别显著缩短了4.0%、4.2%和6.6%;长翅型成虫比例显著增加了11.6%;初羽化成虫体质量降低,且雌成虫体质量显著降低了2.2%;此外,倍增CO₂浓度处理下褐飞虱4龄和5龄若虫口针的刺探效率都显著增加;其中,N4b波的持续时间分别显著延长了60.0%和50.1%,频次分别显著增加了230.0%和155.9%.可见,CO₂浓度倍增可通过提高褐飞虱的刺吸取食而促进其生长发育,并缩短其世代历期、提高长翅成虫比例,最终导致大气CO₂浓度升高下转Bt水稻的非靶标害虫褐飞虱发生危害严重,并面临其迁飞扩散为害加重的风险.     

石菖蒲提取物及混配剂对水稻褐飞虱的控制研究

为了确定石菖蒲(Acorus gramineus Soland)提取物对褐飞虱Nilaparvata lugens St1的活性及使用浓度,研究了石菖蒲提取物对褐飞虱的触杀毒力,30%石菖蒲乳油及30%石菖蒲扑虱灵混配乳油对褐飞虱的室内盆栽试验及大田试验防治效果。结果表明,石菖蒲提取物对褐飞虱3龄若虫及长翅型雌成虫处理48h后的LD50分别为0.64和0.95μg/头。室内盆栽试验表明:30%石菖蒲乳油30倍、30%石菖蒲扑虱灵混配乳油50倍施药3d后对褐飞虱3龄若虫的校正死亡率分别为85.56%和96.67%。30%石菖蒲乳油20倍、30%石菖蒲扑虱灵混配乳油300倍,施药7d后,对褐飞虱的田间防治效果分别为78.46%和79.76%。     

稻田微蛛优势种形成的若干环境因子分析

草间小黑蛛(Erigone graminicolum)和食虫沟瘤蛛(Ummeliata insecticeps)都有较强的耐寒、耐饥能力和较大的捕食量,在-3—0℃时能存活3天左右,平均耐饥历期大于30天,对稻褐飞虱的平均最大捕食量分别为6.3头/天和6.1头/天;Holling模型分别为N_A(草)=0.9886N_0/(1+0.09N_0)和N_A(食)=1.0234N_0/(1+0.101N_0),它们的抗药能力相差无几。但它们对湿度要求不同,前者较后者耐干旱。草间小黑蛛耐干历期雌蛛为27.2天,雄蛛为9.7天;耐湿历期雌蛛为53.2天,雄蛛为46.2天。食虫沟瘤蛛耐干历期雌蛛为7.7天,雄蛛为4.2天;耐湿历期雌蛛为55.4天,雄蛛为49.0天。温度相同湿度不同时它们的竞争能力不同,湿度较小时草间小黑蛛取胜,湿度较大时食虫沟瘤蛛取胜。它们在稻田中成为优势种的条件,主要取决于稻田生境与周围环境的干湿状况。     

Molecular cloning of the murine substance K and substance P receptor genes.

The peptides substance K and substance P evoke a variety of biological responses via distinct, guanosine-nucleotide-binding-regulatory-protein-coupled receptors. We have screened a murine genomic cosmid library using oligonucleotide probes and have isolated, cloned and characterized the substance K receptor and the substance P receptor genes. The coding portion of the substance K receptor gene consists of five exons distributed over 13 kbp. The substance P receptor gene is considerably larger than that of substance K (more than 30 kbp), however, the boundaries of the four exons that have been characterized in the substance P receptor gene correspond exactly to the homologous exons in the substance K receptor gene. To verify the identity of the isolated genes, we have cloned the corresponding cDNA by means of the polymerase chain reaction and we have expressed these cDNA species in Xenopus laevis oocytes. The ligand binding characteristics determined in this system pharmacologically confirm the identity of the two receptors. The deduced amino acid sequence of the mouse substance K receptor is 94% identical to the rat sequence and 85% identical to the bovine and human sequences. The mouse substance P receptor amino acid sequence is 99% identical to the rat sequence. The cloning of the murine substance K and substance P receptor genes should contribute substantially to the generation of in vivo models for the detailed analysis of the functional significance of these receptors.     

Properties of substance P aggregates. Application to the synthesis and purification of substance P

By 1H-NMR spectroscopy it has been shown that Substance P is largely aggregated at basic and acid pH and in saline solutions. These SP polymers dissociate rapidly by addition of pyridine and acetonitrile and slowly by addition of methanol. The difficulties previously encountered in the purification of SP and SP analogs may be attributed to this aggregation and can be overcome under disaggregating conditions. As a first application of our study we propose a reliable method for obtaining SP with good yield.     

Effects of activators and antagonists of the neuropeptides substance P and substance K on cell proliferation in planarians

Substance P and substance K (Neurokinin A) are mammalian peptides belonging to the tachykinin family. Both have been studied extensively, are widely distributed in both central and peripheral mammalian nervous systems, and seem to be involved in pain reactions and inflammatory responses. We report here that substance P and substance K, as well as Epidermal Growth Factor (EGF), are potent mitogens, at micro and nanomolar concentrations, for planarian cells. This stimulation is inhibited by the substance P and substance K antagonist spantide, while capsaicin, a pungent agent of capsicum peppers that destroys sensory neurons, stimulates cell division, probably through release of substance P. These results, jointly with the reported stimulation of cell division by naloxone and its inhibition by Met-Enkephalin (Bagu?a, 1986), both probably acting on tachykinin release, suggest that target cells, the neoblasts, must have in their cell membranes numerous receptors for growth hormones and neuropeptides analogous to their mammalian counterparts.     

A comparison of the anatomical distribution of substance P and substance P receptors in the rat central nervous system

A comparison of anatomical distributions of substance P (SP) and substance P receptors in the rat central nervous system was performed. SP was localized by microdissection and radioimmunoassay and SP fibers and cell bodies by immunohistochemistry. Receptors for ¹²⁵I-Bolton Hunter labelled SP (¹²⁵I-BH-SP) were characterized pharmacologically by a slice binding technique in sections that contained primarily striatum. The receptor was saturable and had an equilibrium dissociation constant (K_D) of 0.30 nM and maximum number of binding sites (B_max) of 37.8 fmol/mg protein. Pharmacological characterization using C terminal fragments and naturally occurring analogues of SP reflected characteristics of the receptor which had been shown previously in bioassays and biochemical assays. Comparison of distribution of SP fibers and cell bodies and SP receptors indicated that there is no consistent relationship between the amount of SP receptor and density of SP fibers or cell bodies in a given region of the brain.     

Isolation and characterization of substance P, substance P 5-11, and substance K from two metastatic ileal carcinoids

Using an antiserum directed at the COOH-terminus of tachykinins, we have examined postmortem tissue from two cases of metastatic ileal carcinoid for the presence of tachykinin-like immunoreactivity. The vast majority of the immunoreactive tachykinin-like material eluted from a Sephadex G-50 column as two peaks at positions corresponding to molecular weights of 1300 and 850. The 1300 dalton peak was resolved by reverse-phase-HPLC into two components which by Edman sequencing, amino acid analysis, and fast atom bombardment (FAB)-mass spectrometry criteria, were identified as substance P and substance K. The 850 dalton peak was also resolved on RP-HPLC into two peaks which were resistant to Edman degradation but from amino acid analysis and FAB-mass spectrometry criteria were identified as pyro-Glu-substance P 5-11 and oxidized pyro-Glu-substance P 5-11. In control experiments substance P 5-11 was converted to pyro-Glu-substance P 5-11 during the extraction procedure. Both tumors also contained a minor immunoreactive peak which eluted from a Sephadex G-50 sizing column at a position corresponding to a molecular weight of 4000 which probably represents neuropeptide K. These results suggest that beta-preprotachykinin is preferentially expressed in carcinoid tumors and that substance K may also play a role in the carcinoid syndrome.     

Nutrients in the shadow-nutrients of substance

While the dietary importance of proteins, essential fatty acids, vitamins and trace elements has been well recognised, the role of shadow nutrients, a class of metabolites, which are biosynthesized in the body and serve vital functions, such as lipoic acid, choline, inositol, taurine and carnitine, has not been adequately appreciated. There are reasons to believe that during infancy and in ageing, biosynthesis of these metabolites may be limited. The objective of this review is to highlight the essentiality of these nutrients and the need for their supplementation in the diets of infants and in elderly people. Provision of shadow nutrients where the necessary biosynthetic machinery might not have developed to full stature or might have slowed down, is a new concept in nutrition which needs attention.     

Valproic acid inhibits substance P-induced activation of protein kinase C epsilon and expression of the substance P receptor

The neuropeptide substance P (SP) has been hypothesized to be involved in the etiopathology of affective disorders. This hypothesis is based on the findings that neurokinin-1-receptor antagonists have antidepressant effects in depressed patients and that SP may worsen mood. In this study, we investigated the effect of the mood-stabilizing agents valproic acid (VPA), carbamazepine, and lithium on SP-induced gene expression. As a model system, we used primary rat astrocytes and human astrocytoma cells, which both express functional SP-receptors and, upon stimulation with SP, synthesize interleukin-6 (IL-6), a cytokine which has been shown to be elevated during the acute depressive state. We found that VPA dose-dependently inhibited SP-induced IL-6 synthesis which was seen with pre-incubation periods of 30 min, 3, 7 and 14 days, whereas carbamazepine and lithium showed no inhibitory effect. The inhibitory effect of VPA was not mediated by inhibition of the stress-regulated kinases p38 and p42/44 (Erk1/2) but by inhibition of protein kinase C epsilon activation. Furthermore, VPA down-regulated the expression of the substance P receptor (neurokinin(NK)-1-receptor) as assessed by real-time PCR. Whether both mechanisms contribute to the mood-stabilizing properties of VPA has to be evaluated in further studies.