紫外线胁迫对红色型豌豆蚜生物学特性的影响

由于臭氧层消耗,南北半球中高纬度地区紫外线(UV-B)胁迫增强,为了探求增强的UV-B胁迫对红色型豌豆蚜生物学特性的影响,以期明确UV-B辐射在豌豆蚜种群演替和种下分化中的作用。本研究以40 W紫外线灯连续辐射处理红色型豌豆蚜8代,每代从初产若蚜开始每天处理1次,连续照射6d,分20、30、40、50和60min 5个处理,并设置白炽灯对照。结果显示,同一世代,随着UV-B辐射时间延长,豌豆蚜体长逐渐减短,体重逐渐减轻,净增殖率、内禀增长率、周限增长率逐渐减小,平均世代周期逐渐延长。同一UV-B辐射时间下,随着世代增加,豌豆蚜体长、体重、净增殖率、内禀增长率、周限增长率均呈先上升后显著下降的趋势,平均世代周期呈先下降后显著上升的趋势。至F8代,不同辐射时间下豌豆蚜平均体长为对照的42.58%~81.94%,平均体重为对照的33.77%~73.12%,净增殖率为对照的6.94%~46.55%,周限增长率为对照的77.00%~87.94%,平均世代周期为对照的1.20~1.38倍,内禀增长率降低,且50~60min处理下小于对照的1/2,种群数量增长放缓。以上说明长期UV-B胁迫对豌豆蚜的生长发育和种群增长最终都有抑制作用。     

The systemic effects of juvenoids on the red firebug Pyrrhocoris apterus and on the pea aphid Acyrthosiphon pisum with data on life table response

BACKGROUND: A series of juvenoid alcohols and their glycosidic derivatives (juvenogens), synthesized at the Institute of Organic Chemistry and Biochemistry in Prague, commercially used juvenoids and the natural derivatives of juvabione were evaluated for their systemic juvenilizing effect on the red firebug, Pyrrhocoris apterus L., and on the pea aphid, Acyrthosiphon pisum Harris. A life table response experiment was designed, and demographic characteristics were computed for a cohort of A. pisum following chronic exposure to a range of concentrations of the selected trans-isomer of carbamate juvenoid 8 applied via the broad bean (Vicia faba L.) root system. RESULTS: Using the ratio of topical and per os activities, promising effects were found in two alkyl beta-D-glucopyranosides (3 and 9) and the trans-isomer of carbamate juvenoid 8 in tests on P. apterus. In A. pisum, the highest systemic activity was found in tests with the trans-isomer of carbamate juvenoid 8. The longevity, the number of offspring per female and the number of offspring per reproducing female significantly decreased with concentrations of 0.05 mg mL(-1) and higher. While the net reproductive rate R(0) and the intrinsic rate of natural increase r(m) displayed similar trends, the generation time G varied slightly between 11.6 and 12.8 days. CONCLUSION: Expected systemic activity of glycosidic juvenogens in P. apterus was not confirmed by exposure of the pea aphid on broad bean treated with aqueous solutions of the compounds. Nevertheless, the carbamate juvenoid alcohol 8 displayed a considerable juvenilizing effect on A. pisum in screening tests. Furthermore, this compound indicated a sublethal effect as the realized fecundity U(x) decreased disproportionately to the age-specific survival L(x) with increased concentration. The population parameters are compared with the data in similar demographic studies and are discussed together with the possibilities of using the compounds of this structural type in practice.     

不同寄主植物对豌豆蚜生长发育和繁殖的影响

[目的]掌握不同寄主植物对豌豆蚜生长发育及繁殖的影响规律。[方法]在(23±1)℃、光照时间16h、相对湿度80%的人工气候箱条件下,组建了豌豆蚜在4种寄主植物上的生命表,统计出种群内禀增长率(rm)、净增殖率(R0)、平均世代周期(T)、种群加倍时间(t)和周限增长率(λ)等种群动态参数。[结果]在蚕豆、豌豆、苜蓿、红豆草4种寄主植物上,豌豆蚜的发育历期存在显著差异,内禀增长率rm分别为0.263 2、0.261 9、0.224 3、0.217 1。[结论]豌豆蚜在蚕豆上的适应度和嗜食性最好,并且繁殖速度最快。     

光周期对两种色型豌豆蚜生长发育的影响

为探讨光周期对两种色型豌豆蚜生长发育的影响,本研究设定了低(103μmol-m-2-s-1)、中(212μmol-m-2-s-1)和高(313μmol-m-2-s-1)3个光照强度,3个光周期(10L∶14D、16L∶8D和22L∶2D),测定了两种色型豌豆蚜的龄期、发育历期、体重差、相对日均体重增长率等生物学参数的变化特征。结果表明:在低光照强度下,光周期10L∶14D时,绿色型比红色型豌豆蚜4龄期延长0.21 d(P0.05),发育历期延长,其他各项指标无显著差异(P0.05);光周期16L∶8D时,红色型比绿色型豌豆蚜3龄期延长0.52 d(P0.05),发育历期延长;光周期22L∶2D时,绿色型比红色型豌豆蚜2龄期、4龄期延长0.12 d、0.22 d,差异显著(P0.05),其他指标无显著差异(P0.05)。中光照强度下,光周期10L∶14D时,绿色型比红色型豌豆蚜体重差减轻6.76%,相对日均体重增长率减小14.63%,均为差异显著(P0.05),发育历期无显著差异(P0.05);光周期16L∶8D时,绿色型比红色型豌豆蚜1龄期、2龄期、4龄期延长0.23 d、0.60 d、0.33 d,发育历期延长,体重差减轻28.84%,相对日均体重增长率减小37.21%,均为差异显著(P0.05);光周期22L∶2D时,红色型比绿色型豌豆蚜相对日均体重增长率增高12%(P0.05)。高光照强度下,光周期10L∶14D时,绿色型比红色型豌豆蚜4龄期延长0.58 d(P0.05);光周期16L∶8D时,绿色型比红色型豌豆蚜1龄期延长1.63 d(P0.05);光周期22L∶2D时,红色型豌豆蚜发育历期延长,体重差和相对日均体重增长率无显著差异(P0.05)。综上,在不同光照强度下,光照时间越长,两种色型豌豆蚜生长发育越好;光照强度越强,光周期越短,两种色型豌豆蚜生长发育显著迟缓。由此可见,光周期对两种色型豌豆蚜生长发育的影响与光照强度相关,且红色和绿色型豌豆蚜对光周期的反应均不相同。     

连续UV-B胁迫对绿色型豌豆蚜生物学特性的影响

为了明确连续UV-B胁迫对绿色型豌豆蚜生长发育及种群参数的影响,将12 h内所产绿色型豌豆蚜若蚜经40 W UV-B辐射连续处理8代,每代6次,每天1次,每次分别处理20 min、30 min、40 min、50 min和60 min,每次处理后单头饲养,最终采用实验种群生命表方法进行评价,获得多代种群内禀增长率(rm)、净增殖率(R0)、平均世代周期(T)和周限增长率(λ)等生命参数。结果显示,随着辐射时间延长,世代数增加,各处理下若蚜历期最终延长,最长为8.11 d,成蚜寿命先延长后缩短,F8代为对照的6.71%~21.27%;净增殖率先升高后降低,F8代为对照的0.20%~22.32%;内禀增长率在F8代时显著降低,最高为对照的11.05%;周限增长率先升高后缩短,F8代为对照的0.90%~22.14%;F8代平均世代周期显著缩短,相对于对照减短8.54%~21.11%。连续UV-B胁迫试验中,处理时间越长,随着世代数增多,UV-B对绿色型豌豆蚜生长发育和繁殖抑制作用越强,种群数量增长越慢。     

豌豆品种对绿色型豌豆蚜种群参数的影响

在(23±1)℃、光照时间16 h、相对湿度70%~80%人工气候箱条件下,研究了"草豌豆"、"定豌1号"、"定豌2号"、"G1997"4个豌豆品种对绿色型豌豆蚜种群变化的影响,旨在为种植豌豆时品种的选择提供理论依据。结果表明,在不同豌豆品种上绿色型豌豆蚜的各虫态发育历期和单雌一生最高产仔量均有显著差异,其在"G1997"上完成一生所需时间最长(17.92 d),在"草豌豆"上最短(12.69 d);其最高产仔量在"G1997"上最多,为117头.头1,在"草豌豆"上最少,为60头.头1。存活曲线均为Ⅰ型,存活率高低依次为"G1997"、"定豌2号"、"定豌1号"和"草豌豆";净增值率"定豌2号"、"定豌1号"、"G1997"、"草豌豆"相应分别为40.569 2、37.952 4、31.607 8、25.000 0;内禀增长率在"定豌1号"上最大,为0.275 8,而在"G1997"上最小,为0.188 6;种群加倍时间依次为"G1997"(3.675 0 d)、"定豌2号"(2.867 6 d)、"草豌豆"(2.729 8 d)和"定豌1号"(2.513 1 d);"定豌1号"是其最喜食的品种,其次为"定豌2号"、"草豌豆",最后是"G1997"。     

Per os efficacy of Ajuga extracts against sucking insects

We studied the efficacy of water-soluble extracts from four Ajuga spp on the post-embryonic development of two exopterygota (sucking insect) species. To allow comparison between different Ajuga species, results are expressed in terms of quantity of plant extracted per litre of test solution. Crude methanolic extracts of all Ajuga plants tested, with the exception of A genevensis, showed considerable per os efficacy against larvae of both Dysdercus cingulatus F and Acyrthosiphon pisum (Harris) even at 1 g litre(-1). In the aphid tests the order of efficacy was A bracteosa Wallich ex Benth > A chamaepitys Schreber > A reptans L > A genevensis L. On D cingulatus the order of efficacy was: A reptans > A bracteosa > A chamaepitys > A genevensis. Extracts were fractionated on SepPak using a range of methanol/water mixtures. Results are expressed in terms of the initial weight of plant extracted. The 100% methanolic fraction of A chamaepitys was highly effective on A pisum (100% mortality at 1 g litre(-1)) and less effective on D cingulatus (about 60% mortality at 5 g litre(-1)). The entire 60 methanol + 40 water fraction was effective against test insects but showed different efficacies according to test species and concentration applied. 20-Hydroxyecdysone (20E), cyasterone (Cy) and ajugalactone (Ajl) were identified in the fractions from all Ajuga species, but the remaining phytoecdysteroid profile was quite different between Ajuga species. Capitasterone (Cap) and 28-epi-sengosterone (5Cy28') were found only in A reptans, makisterone A (MaA) and 29-norcyasterone (29NCy) were only in A chamaepitys, while 22-acetylcyasterone (Cy22A), 3-epi-cyasterone (Cy') and 3-epi-22-acetylcyasterone (Cy'22A) were only in A bracteosa. The total amount of phytoecdysteroids was 2053 mgkg(-1) for A bracteosa, 1892 mgkg(-1) for A reptans and 95 mg kg(-1) for A chamaepitys.     

龟纹瓢虫成虫对苜蓿豌豆蚜的捕食功能反应

[目的]了解龟纹瓢虫成虫控制苜蓿豌豆蚜的能力。[方法]在实验室内,测定未饥饿和饥饿24h的龟纹瓢虫成虫对苜蓿豌豆蚜的捕食功能反应。[结果]龟纹瓢虫捕食苜蓿豌豆蚜的数量与苜蓿豌豆蚜密度呈负加速曲线关系,符合Honing-Ⅱ型功能反应模型,x2检验表明圆盘方程的理论值与实测值相符,捕食作用在一定范围内随猎物密度的增加而加大。未饥饿和饥饿24h的龟纹瓢虫捕食苜蓿豌豆蚜的功能方程分别为:1/Na=1.512(1/N)+0.0302、1/Na=1.0875(1/N)+0.0109,未饥饿与饥饿24h的龟纹瓢虫成虫对苜蓿豌豆蚜的日最大捕食量分别为33.11、91.74头。[结论]龟纹瓢虫成虫对苜蓿豌豆蚜的捕食作用较大,对其发生具有一定的调控作用。     

豌豆蚜刺吸胁迫对不同苜蓿品种体内单宁含量及生理活性的影响

通过对甘农5号(G5)、甘农3号(G3)、金皇后(JH)和猎人河(Hu)4种不同抗蚜苜蓿(Medicago sativa L.)品种受豌豆蚜(Acyrthosiphon pisum)胁迫后其叶片内丙二醛(MDA)和单宁含量及防御性酶(超氧化物歧化酶(SOD)和过氧化物酶(POD))活性的动态变化研究,以期明确各项生理指标与抗虫性之间的关系。结果表明:在蚜虫刺吸诱导过程中,抗虫品种(G5)的MDA含量低于低抗品种(G3)和感虫品种(JH),抗虫品种和感虫品种的单宁含量高于低抗品种,感虫品种的SOD和POD活性低于抗虫品种和低抗品种,且所有品种的SOD和POD活性均表现先上升后下降的趋势,而MDA和单宁含量变化无规律。因此,MDA,SOD和POD活性的变化与苜蓿的抗蚜性密切相关,可作为苜蓿抗蚜性生理指标,而单宁与苜蓿抗蚜性的关系有待进一步研究。