首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 93 毫秒
1.
在用棉花、大豆、花生功能叶饲养棉铃虫幼虫的基础上,测定各寄主功能叶的营养成分、木质素和纤维素含量,研究棉铃虫在取食不同寄主叶片后的生物学和营养效应。结果表明:1、取食棉花叶的生物学效应较好,取食花生叶的幼虫成活率下降,取食大豆叶的幼虫体重偏轻;2、取食棉花叶的营养效应较好,大豆叶最次;3、棉铃虫幼虫的食物转化率和食物利用率以棉花叶最高,棉铃虫嗜食棉花叶,在3种作物田同时存在的情况下,棉田被害最重。  相似文献   

2.
采用RT-PCR结合RACE技术从陆地棉中棉所12中克隆得到全长为1280 bp的苯甲酸/水杨酸羧基甲基转移酶基因序列,命名为GhBSMT1。预测该转移酶分子量40.8 kD,等电点6.12,为不稳定的亲水蛋白。通过原核表达获得大小约41 k D的可溶性重组目标蛋白。利用实时荧光定量PCR技术检测了棉花中GhBSMT1在植物激素处理和棉铃虫取食后表达转录情况,发现GhBSMT1在棉花的根、茎和叶中均有表达。水杨酸甲酯(Me SA)处理能够引起GhBSMT1下调表达,而茉莉酸甲酯(Me JA)处理对靶标基因影响不显著。另外,棉铃虫取食棉株6 h或48 h后,GhBSMT1表达量显著降低。结果表明,GhBSMT1在棉花各组织均有分布并受外源Me SA调控,该基因的表达还被棉铃虫取食抑制。  相似文献   

3.
利用室内饲喂法,以抗Cry1Ac近等基因系棉铃虫为材料,比较转基因棉花33B和SGK321及其对照亲本DP5415和石远321对抗、感棉铃虫生长发育的影响。结果表明,抗性棉铃虫在取食常规棉叶后表现出一定的适合度代价。取食DP5415和石远321两种常规棉花后,抗性品系棉铃虫的幼虫存活率显著低于敏感品系,取食33B和SGK321两种转基因棉花的抗性棉铃虫,不仅其幼虫存活率显著高于敏感品系,而且致死中时间也比敏感品系延长。取食9天后,抗性品系在常规棉花石远321和DP5415上发育到3龄和4龄幼虫的比例显著低于敏感品系,取食33B和SGK321转基因棉花的抗性品系发育到3龄幼虫的比例均显著高于敏感品系。抗性品系在常规棉上的蛹重均显著低于敏感品系,部分取食转基因棉花的抗性品系棉铃虫可以化蛹,而敏感品系不能在转基因棉花上化蛹。  相似文献   

4.
载脂蛋白受体(lipophorin receptor, LpR)在昆虫体内脂质转运中发挥重要作用。为了明确棉铃虫载脂蛋白受体基因在其卵巢发育及饥饿胁迫中的功能, 本研究克隆了棉铃虫 HaLpR 基因的cDNA序列(GenBank登录号KU355886.1), 全长3 117 bp, 开放阅读框为2 643 bp, 编码880个氨基酸; 其氨基酸序列包含典型的低密度脂蛋白受体结构域, 与其他鳞翅目昆虫的LpR相似度>80%。荧光定量PCR检测结果显示, HaLpR 在雌蛾的卵巢和脂肪体组织中相对转录水平最高; 在雌蛾卵子发生期均有转录, 在雌蛾羽化后3 d表达量达到最高峰; 饥饿处理会抑制 HaLpR 在雌蛾卵巢和脂肪体中的转录。研究结果有助于解析HaLpR参与棉铃虫卵巢发育过程中的脂质转运以及应对饥饿胁迫的作用。  相似文献   

5.
为明确N6-甲基腺苷(N6-methyladenosine,m6A)修饰在棉铃虫核型多角体病毒(Helicoverpa armigera nucleopolyhedrovirus,HearNPV)侵染棉铃虫中的作用,根据基因组和转录组数据,对棉铃虫m6A结合蛋白基因YTHDF1(YTH domain-containing family protein 1)进行鉴定和分析,利用实时荧光定量PCR技术检测棉铃虫YTHDF1基因的时空表达模式、HearNPV处理后的表达变化情况以及RNA干扰效率,并调查该基因下调后对HearNPV复制及感染HearNPV棉铃虫死亡情况的影响。结果显示,棉铃虫YTHDF1基因开放阅读框全长为2 019 bp,编码672个氨基酸,含有1个保守的YTH结构域,其氨基酸序列与斜纹夜蛾Spodoptera litura同源物序列一致性达87.52%。YTHDF1基因在棉铃虫不同发育阶段均有表达,其中在进入5龄期24 h幼虫中的表达量最高,在2龄取食期幼虫中的表达量最低。YTHDF1基因的空间表达谱呈现一定的组织特异性,在幼虫血细胞和成虫头部的表达量最高。HearNPV侵染棉铃虫后YTHDF1基因上调表达,经RNA干扰使该基因下调后显著抑制了HearNPV多角体蛋白基因polyhedrin的表达并延迟了感染HearNPV棉铃虫的死亡时间。表明YTHDF1基因在HearNPV侵染棉铃虫的过程中发挥着重要作用。  相似文献   

6.
为评估转Cry1Ac/1Ab基因棉花对棉铃虫Helicoverpa armigera的抗性及对非靶标害虫甜菜夜蛾Spodoptera exigua和斜纹夜蛾S.litura生长发育的影响,采用室内生测法测定其对棉铃虫的抗性及对甜菜夜蛾和斜纹夜蛾不同龄期幼虫存活率、营养代谢及中肠酶活性的影响。结果表明,转Cry1Ac/1Ab基因棉花对棉铃虫第2代幼虫的抗性程度最高,幼虫校正死亡率达91.33%,但对甜菜夜蛾和斜纹夜蛾的抗性程度较低,幼虫校正死亡率分别为15.33%和13.33%。甜菜夜蛾和斜纹夜蛾各龄期幼虫取食转Cry1Ac/1Ab基因棉花后,其存活率与取食常规棉花对照无显著差异;甜菜夜蛾对转Cry1Ac/1Ab基因棉花叶片的相对取食量、近似消化率分别为16.68和93.12%,均高于取食常规棉花对照的10.72和92.00%,但差异不显著,而斜纹夜蛾取食转Cry1Ac/1Ab基因棉花后的各项营养指标均低于取食常规棉花对照,差异也不显著。取食转Cry1Ac/1Ab基因棉花后,甜菜夜蛾的过氧化物酶活性为0.02 U/mg prot,显著低于取食常规棉花的0.05 U/mg prot;斜纹夜蛾的酸性磷酸酶活性为0.15 U/mg prot,高于取食常规棉花的0.10 U/mg prot,但差异不显著,其它中肠酶活性均低于对照,亦无显著差异。  相似文献   

7.
室内测定了转慈姑蛋白酶抑制素(API)基因棉对棉铃虫幼虫的抗虫活性及对中肠蛋白酶活性的影响。结果表明,以转基因棉饲养棉铃虫,对幼虫拒食率24h达76.49%,72h达80.57%,试虫体重在取食48h后显著下降,72h后较对照低54.04%。试虫取食转API基因棉后,中肠的强碱性胰蛋白酶和类胰凝乳蛋白酶活性显著降低,取食24、48h后的强碱性胰蛋白酶酶活性分别只有对照组的68.1l%和55.89%;类胰蛋白酶活性分别为对照组的85.87%和64.61%;对弱碱性类胰蛋白酶活性不明显。显示转API基因棉对棉铃虫幼虫中肠蛋白酶的抑制作用与对棉铃虫生长发育的阻滞有良好的相关性。  相似文献   

8.
为明确美洲棉铃虫Helicoverpa zea幼虫腹侧可外翻腺(ventral eversible gland,VEG)分泌物对植物抗虫反应的影响,在宾夕法尼亚州立大学帕克分校校园日光温室大棚内分别测定取食未损伤、机械损伤后涂抹磷酸缓冲盐溶液(phosphate buffer saline,PBS)和机械损伤后涂抹VEG分泌物3种处理的番茄叶片后美洲棉铃虫幼虫体重增加量,不同处理番茄叶片中防御关键酶多酚氧化酶(polyphenol oxidase,PPO)活性、胰蛋白酶抑制剂(trypsin proteinase inhibitors,TPI)抑制率以及防御相关的蛋白酶抑制剂Ⅱ(proteinase inhibitor Ⅱ,PIN2)基因相对表达量。结果显示,3种处理中,取食机械损伤后涂抹VEG分泌物的番茄叶片的美洲棉铃虫幼虫体重较处理前增加量最少,为4.27 mg,显著低于其它2种处理;机械损伤后涂抹VEG分泌物的番茄叶片中PPO活性和TPI抑制率最高,分别为109.16 U/mg和27.48%,分别显著高于其它2种处理;同时机械损伤后涂抹VEG分泌物的番茄叶片中PIN2基因相对表达量显著上调,分别是未损伤和机械损伤后涂抹PBS缓冲液处理的11.83倍和1.17倍。表明美洲棉铃虫幼虫VEG分泌物能够促使防御关键酶的大量积累,使得防御相关基因的相对表达量上调,显著诱导番茄的抗虫反应,阻止后续昆虫的取食。  相似文献   

9.
棉铃虫多代连续取食转基因抗虫棉的抗性演变   总被引:11,自引:0,他引:11  
1997-1999年,用含45%Bt CPT1双抗基因棉半人工饲料饲喂棉铃虫幼虫5.5天,连续16代汰选。结果:幼虫校正死亡率由79.18%下降到49.36%;其体长达取食45%泗棉3号半人工饲料幼虫平均体长,由第一代的0上升到第16代的23.32%;幼虫体长、体重增长速率由第一代负增长分别上升为55.29%和366.67%。表明棉铃虫幼虫经取食转基因抗虫棉连续16代,其中肠对抗虫棉已产生一定的亲和性及适宜性,进入早期抗性阶段。  相似文献   

10.
江苏沿海棉区转Bt基因抗虫棉种植效应研究   总被引:6,自引:0,他引:6  
通过常规棉苏棉9号与4个转Bt基因抗虫棉的系统对比,明确了抗虫棉的抗虫增产效应;取食转Bt基因抗虫棉营养器官的棉铃虫幼虫死亡率高,残虫基本不能化蛹;抗虫棉对棉田。其它的鳞翅目昆虫幼虫有兼抗作用;在棉铃虫中等发生年份,2、3代无需专门防治,4代可按虫量指标防治1-2次,最终比苏棉9号增产一成左右,节省药工费60%以上,增收1500元/hm^2以上,并且有利于天敌增殖,经济、社会、生态效益明显。  相似文献   

11.
为明确云南省元阳县籼/粳型稻瘟病菌中无毒基因的多样性及差异,采用接种鉴别品种方法和PCR技术对9株粳型菌株和21株籼型菌株中无毒基因Avr-Pia、Avr-Pita1和Avr-Pii的多样性进行分析。结果显示,30株稻瘟病菌菌株中无毒基因Avr-Pia、Avr-Pita1和Avr-Pii的平均出现频率分别为33.3%、76.7%和0,Avr-Pia、Avr-Pita1在籼型菌株和粳型菌株中的出现频率分别为4.8%和100.0%、66.7%和100.0%。Avr-Pia主要为存在/缺失的多样性,籼/粳型菌株对水稻品种Achiasahi(Pia)的致病率分别为100.0%和11.1%;Avr-Pita1可划分为3个类群,除菌株CH1195属于PO类群外,籼型菌株均属于J1类群,粳型菌株则属于J2/J3类群;籼/粳型菌株对水稻品种K1(Pita)的致病率分别为100.0%和0,且籼/粳型菌株Avr-Pita1蛋白序列在第83位和第192位氨基酸差异明显。Avr-Pii在30株稻瘟病菌菌株中均未检出,籼/粳型菌株对水稻品种Fujisaka No. 5(Pii)的致病率分别为100.0%和0。表明Avr-Pia和Avr-Pita1在粳型菌株中的出现频率高于籼型菌株且变异程度低,粳型菌株中可能存在其它无毒基因使其不能侵染Fujisaka No. 5。  相似文献   

12.
Fusarium graminearum, Fusarium culmorum and Fusarium cerealis are major causal agents of Fusarium Head Blight (scab) which is a disease of global significance in all cereal growing areas. These fungi produce trichothecene mycotoxins, principally nivalenol (NIV) and deoxynivalenol (DON). Genes Tri13 and Tri7 from the trichothecene biosynthetic gene cluster convert DON to NIV (Tri13) and NIV to 4-acetyl-NIV (Tri7). We have developed positive–negative PCR assays based on these two genes, which accurately indicate a DON or NIV chemotype in F. graminearum, F. culmorum and F. cerealis. These assays are useful in assessing the risk of trichothecene contamination, and can be informative in epidemiological studies. All NIV chemotype isolates studied have functional copies of both Tri13 and Tri7, and all DON-producing isolates have both genes disrupted or deleted. We have identified several mutations in these genes, which are conserved across F. graminearum lineage, RAPD and SCAR groupings and between the three species. There appears to be evidence of inter-species hybridisation within the trichothecene biosynthetic gene cluster.  相似文献   

13.
Floral malformation caused by Fusarium mangiferae is a serious threat to mango cultivation in various countries. Different long-term measures suggested to control it were found to be unsuccessful. Present studies clearly showed strong antifungal activity of a concoction brewed from Datura stramonium, Calotropis gigantea, Azadirachta indica (neem) and cow manure (T1) followed by methanol-water (70/30 v/v) extracts of Datura stramonium, Calotropis gigantea and Azadirachta indica (T2) against Fusarium mangiferae. Optimal control of floral malformation was found in trees sprayed with T1 followed by T2 at bud break stage and again at fruit set stage when compared with the control. All the malformed buds or panicles completely dried two days after foliar spray with T1 or T2. In the trees treated with T1 at fruit set stage, flower abscission was observed from the fourth day after spraying and all flowers dropped by the ninth day without requiring any manual de-blossoming, whereas in the control, the malformed panicles remained green and competed with the growing fruits for plant nutrients. In vitro culture of fresh malformed tissues in MS media along with T1 or T2 showed no growth of any fungus in the media. However, in vitro culture of the completely dry malformed tissues in MS media after foliar treatment with T1 or T2 revealed growth of F. mangiferae on the twenty fifth day indicating that the concoction-brewed compost (T1) or methanol-water (70/30 v/v) extracts (T2) could not completely eliminate the pathogen but helped in controlling malformation by suppressing the activity of F. mangiferae. Mango trees sprayed with T1 and T2 revealed significant differences in percent fruit set and retention when compared with the control. This could be due to observed higher levels of nitrogen, phosphorus, potassium, calcium, magnesium, copper, zinc, iron and manganese in T1, followed by T2 when compared with T3 (control). Among the different fruit quality parameters analysed, the total flavonoids were found to be significantly higher in T1 and T2 when compared with T3. The study proved that the concoction-brewed compost (T1) is effective, inexpensive, easy to prepare and constitutes a sustainable and eco-friendly approach to control floral malformation in mango when it is sprayed at bud break stage and again at fruit set stage. In this present study, exogenous treatment of emerging buds with (Tc) further proved that with increase in the number of malformed panicles/tree the number of buds developing into healthy panicles/tree decrease.  相似文献   

14.
玫烟色棒束孢与球孢白僵菌对桃蚜致病力对比   总被引:3,自引:2,他引:1  
为选取具有杀蚜潜力的虫生真菌,采用喷雾法比较研究了玫烟色棒束孢IF-1106和球孢白僵菌BB-1339对桃蚜成蚜的致病力,并利用时间-剂量-死亡率模型估计了2菌株对桃蚜的致死剂量与致死时间。结果表明,菌株IF-1106侵染桃蚜后菌丝如棉絮状,形成淡玫瑰色分生孢子,且菌丝侵染速度快于菌株BB-1339;菌株BB-1339侵染桃蚜后菌丝短而致密,形成白色分生孢子。菌株IF-1106在浓度为1×108 CFU/mL时,累计死亡率达到91.7%,而菌株BB-1339最高仅为55.0%。时间-剂量-死亡率模型中Hosmer-Lemeshow方法拟合异质性检验表明模型拟合良好,在接种后7 d,菌株IF-1106和BB-1339对桃蚜的半致死浓度分别为1.20×105 CFU/mL和8.15×107 CFU/mL;当浓度为1×108 CFU/mL时,2菌株对桃蚜的半致死时间分别为4.2 d和6.8 d。表明菌株IF-1106对桃蚜的致病力高于菌株BB-1339,更具开发潜力。  相似文献   

15.
三种常用农药对环棱螺、圆田螺和河蚬的急性毒性研究   总被引:2,自引:0,他引:2  
采用急性毒性试验方法,研究了3种常用农药毒死蜱、丁草胺和三唑酮对3种本地底栖生物环棱螺Bellamya quadrata、圆田螺Cipangopaludina cathayensis和河蚬Corbicula fluminea的毒性效应,同时测定了螺类不同大小个体对供试农药的敏感性。结果显示:毒死蜱、丁草胺和三唑酮对环棱螺的96 h-LC50值分别为4.32、3.62和15.2 mg/L,对圆田螺的96 h-LC50值分别为6.31、4.31和16.9 mg/L,对河蚬的96 h-LC50值分别为8.75、6.83和26.5 mg/L;毒死蜱和丁草胺对3种供试生物均为中等毒性,三唑酮属低毒。环棱螺幼螺对毒死蜱、丁草胺和三唑酮的敏感性分别比大螺高2.52、1.84和1.72倍,圆田螺幼螺对毒死蜱、丁草胺和三唑酮的敏感性分别比大螺高2.26、2.26和2.67倍。因此,在田间使用3种供试农药时需注意对供试底栖生物尤其是其幼体的保护。  相似文献   

16.
The effects of Glomus intraradices, Pseudomonas alcaligenes and Bacillus pumilus on the root-rot disease complex caused by the root-knot nematode Meloidogyne incognita and the root-rot fungus Macrophomina phaseolina in chickpea was assessed by quantifying differences in the shoot dry mass, pod number, nodulation, and shoot content of chlorophyll, nitrogen, phosphorus and potassium. Inoculation of plants with G. intraradices, P. alcaligenes and B. pumilus alone and in combination significantly increased shoot dry mass, pod number, and content of chlorophyll, nitrogen, phosphorus and potassium in plants inoculated with pathogens over that in the uninoculated control plants. P. alcaligenes caused a greater increase in shoot dry mass, pod number, chlorophyll, nitrogen, phosphorus and potassium in plants with pathogens than did G. intraradices or B. pumilus. Combined application of G. intraradices, P. alcaligenes and B. pumilus to plants inoculated with pathogens caused a greater increase in shoot dry mass, pod number, nitrogen, phosphorus, and potassium than did an application of P. alcaligenes plus B. pumilus or of G. intraradices plus B. pumilus. Root colonization by G. intrardices was high when used alone, while inoculation with the pathogens reduced root colonization by G. intraradices. In the presence of P. alcaligenes and B. pumilus, root colonization by G. intraradices increased. In plants inoculated with just one antagonist, P. alcaligenes reduced galling and nematode multiplication the most, followed by G. intraradices, then B. pumilus. The greatest reduction in galling, nematode multiplication and root-rot was observed when both bacterial species and G. intraradices were applied together.  相似文献   

17.
Restriction fragment length polymorphism (RFLP) analysis of the PCR amplified fragments of recA, gyrA and rpoS genes was applied for the characterization of Erwinia amylovora and Erwinia strains, which cause fire blight and Asian pear blight in orchards. Primers, constructed on the basis of the published recA, gyrA and rpoS gene sequences of Erwinia carotovora, allowed us to amplify DNA fragments for RFLP differentiation of E. amylovora and E. pyrifoliae and finally to distinguish strains within these species and relate them to pear pathogens from Japan. Three to seven restriction endonucleases were applied for RFLP analysis of each gene fragment. The electrophoretic patterns generated after PCR–RFLP for each of the tested genes, were characteristic and specific for each species and allowed their differentiation. The data show that PCR–RFLP analysis of the recA, gyrA and rpoS gene fragments may be considered as a useful tool for the identification and differentiation of E. amylovora and E. pyrifoliae. Almost identical restriction patterns of the analyzed gene fragments indicated a high relationship of E. pyrifoliae strains from Korea and pear pathogens from Japan and a divergence to E. amylovora. For quick and effective differentiation of E. amylovora strains from Erwinia strains from Asia without nucleotide sequencing we recommend the amplification of recA and rpoS gene fragments and digestion of each of them with restriction endonuclease Hin6I.  相似文献   

18.
为了解决深圳特区甜玉米产区日趋严重的农药污染问题,笔者在深圳龙岗生态示范农场甜玉米地研究了玉米螟赤眼蜂Trichogramma ostriniae的应用技术,分析了玉米螟赤眼蜂释放量、释放次数对亚洲玉米螟Ostrinia furnacalis Guen6e控制作用的关系,提出了最件释放方法.  相似文献   

19.
20.
研究了昆虫病原线虫共生细菌4个种和1组未定名种28个菌株发酵液对棉铃虫、菜青虫幼虫的致死、抑制生长和拒食作用。嗜线虫致病杆菌对棉铃虫幼虫具有较高的口服毒性,含20%(V/W)嗜线虫致病杆菌CBl2、CB6、CB5、CB28菌株发酵液的人工饲料饲喂棉铃虫初孵幼虫6天后,幼虫校正死亡率分别为97.7%、88.7%、88.4%和88.4%,饲喂棉铃虫3龄幼虫5天后,相对生长抑制率分别为96.4%、95.1%、95.6%和93.8%,上述菌株发酵原液涂抹白菜叶片饲喂5龄棉铃虫幼虫24h后相对拒食率分别为87.6%、83.6%、91.4%和89.8%;光杆状菌CBl、cBl52菌株、嗜线虫致病杆菌CB19菌株和波氏致病杆菌CB32菌株发酵原液涂抹白菜叶片饲喂菜青虫24h后,相对拒食率分别为82.7%、77.2%、75.8%和75.0%。  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号