嗜卷书虱抗气调品系的选育及其适合度研究

于恒温条件下以人工饲料饲养的嗜卷书虱Liposcelis bostrychophila,在35% CO₂和1% O₂组配的气调环境中以50%左右的选择压力处理,以选育其抗气调性。至30代获得抗性品系(CA-R),抗性倍数达5.6倍,且有继续增强的基因潜能。该抗性品系对气调的抗性不太稳定,在无选择压力的情况下经室内5代饲养,抗性衰退了63.2%。CA-R品系与敏感品系在无气调选择压力的条件下相比具有一定程度的繁殖不利性;但没有发现CA-R品系在生长发育特性上的不利性。以净增殖率来衡量,CA-R品系相对于敏感品系具有0.39的适合度。     

嗜卷书虱低氧耐性品系的选育及其遗传稳定性和生态适合度研究

室内恒温条件下以人工饲料饲养的嗜卷书虱Ｌｉｐｏｓｃｅｌｉｓ ｂｏｓｔｒｙｃｈｏｐｈｉｌａ Ｂａｄｏｎｎｅｌ成虫,分别在０．５％和１％Ｏ２组配的气调环境中以７％左右的选择压力处理,以选育其耐低氧气调性。选育至３０低氧品系ＬＯＣ１和ＬＯＣ２,以ＬＴ５０为标准其性倍数分别达４．７和３．９倍。整个选育过程中,气调暴露时间对数值与死亡率机率值间的回归直线基本平行,其值均低于敏感基线的斜率值,这表明嗜卷书虱对     

嗜卷书虱抗气调性的一些生物化学特性研究(英文)

嗜卷书虱成虫于２８°Ｃ、７０％—８０％ＲＨ条件下,在３５％ＣＯ２。和１％Ｏ２。组配的气调环境中连续暴露３０代,选择压力保持在７０％左右,以选育其抗气调性。至第３０代,以ＬＴ５０。为指标衡量其抗性倍数达５．６倍。生化分析表明,抗性选育过程中离体羧酸酯酶（ＣａｒＥ）和超氧化物歧化酶（ＳＯＤ）活力均随选育代数的增多而显著增强,且酶活力与抗气调水平显著相关。第３０代,抗性品系（ＣＡ－Ｒ）的ＣａｒＥ和ＳＯＤ活力分别是敏感品系（ＣＡ－Ｓ）的４．０６和５．２２倍。两品系暴露于气调环境中,其ＣａｒＥ活力均受抑制,但对ＣＡ－Ｓ品系的抑制率显著强于ＣＡ－Ｒ品系。短时间的气调暴露对ＳＯＤ具有诱导作用,但诱导作用的时间及强度ＣＡ－Ｒ品系明显长（强）于ＣＡ－Ｓ品系。离体过氧化氢酶（ＣＡＴ）活力也随着抗气调性的增强而增强,但两着之间并无显著的相关性。抗性选育过程中离休酸性磷酸酯酶（ＡＣＰ）和碱性磷酸酯酶（ＡＬＰ）活力均未发生明显的变化。过氧化物酶（ＰＯＤ）在两品系中均未检测出。由此看出,ＣａｒＥ和ＳＯＤ活力增强是嗜卷书虱抗气调性形成的主要机制,ＣＡＴ可能对低氧气调抗性的形成具有辅助作用。     

嗜卷书虱的实验生态研究

在8种温度(17.5～35℃)及5种相对湿度(50%、60%、70%、80%和90%)条件下,以全麦粉、酵母粉、脱脂奶粉(10∶1∶1)为食料,系统研究了嗜卷书虱Liposcelis bostrychophila Badonnel实验种群生态学特性。获得了该虫在不同温、湿度条件下生长发育、生存和繁殖的一系列特性和参数,包括各虫态发育历期、存活率、发育起点温度、有效积温和平均繁殖力等,并建立了发育速率、存活率及繁殖力的理论模型。     

储藏物害虫嗜虫书虱的生物学研究(英文)

以全麦粉和酵母粉（10：1）为饲料,分别在8种温度（17．5－35℃）及5种相对湿度（50％－90％RH）条件下系统地研究了嗜虫书虱的生物学特性,获得了其在不同温、湿度组合情况下的生长发育、生存和繁殖的一系列特性和参数。结果表明,在75％RH、20－35℃范围内,世代发育历期在71．9－21．7天之间。世代发育起点温度和有效积温分别为15．7℃和460．7日·度。各虫态及世代存活率均以27．5℃时最高,温度过高或过低均不利于该虫存活。成虫平均寿命在64．4－32．4天之间。每雌平均产卵量为21．1－13．9粒。在28℃条件下,较高的相对温度有利于该虫生长发育和繁殖。相对湿度低于50％或温度低于17．5℃,该虫均不能完成世代发耷。总体来看该虫生长发育、繁殖的最适温区为28－30℃,最适相对湿度在80％—90％之间并就该虫在我国分布及为害严重的原因进行了探讨。     

甜菜夜蛾虫酰肼抗性品系选育及相对适合度研究

本试验在室内对甜菜夜蛾Spodoptera exigua(Hübner)武汉敏感品系进行了8代群体汰选后分别于9、10、12代采用了单对汰选。结果表明虫酰肼处理后各单对品系后代幼虫存活率发生明显分离,F9(s1)、F10(s2)和F12(s3)代幼虫平均存活率分别为48.34%、11.72%和2.37%,筛选后分别为84.00%、83.33%和7.29%。经过12代汰选后,汰选品系抗性倍数为敏感品系的5.24倍,且单对汰选世代对虫酰肼的抗性发展较快,其抗性倍数分别是群体汰选的1.27、1.67和1.38倍。比较单对汰选世代与群体汰选世代某些生物学特性,显示单对汰选世代并不存在生长发育和生殖不利性,表明在虫酰肼群体汰选中穿插几代单对汰选可以加速抗性品系的选育。汰选品系相对于敏感品系具有0.31的适合度,表明甜菜夜蛾对虫酰肼产生抗性后存在适合度缺陷。     

嗜卷书虱实验种群生命表的研究

在不同温度和湿度条件下对嗜卷书虱进行饲养,分别组建春实验种群特定年龄和特定时间生命表,并应用Morris模式及SWeibull频数分布以探讨温、湿度与嗜卷书虱种群数量变动的关系。结果表明,温、湿度对存活率的作用是影响该实验种群趋势指数（I）值最重要的因子,在适宜温、湿度条件下,种群存活曲线属DeeveyⅠ型,而在不太适宜条件下则属DeeveyⅢ型,理论上30.63℃时周限增长率（λ）最大,达1.0628倍／天,该虫发育和繁殖的最适温区为28-30℃,最适相对湿度在80％左右。     

褐飞虱抗吡虫啉品系生物适合度研究

毒力测定结果显示 ,虽然褐飞虱NilaparvatalugensSt l田间品系对吡虫啉还没有表现出明显的抗性 ,但室内筛选品系已经出现了一定水平的抗性 ,抗性品系 1 (R1)和抗性品系 2 (R2 )的抗性倍数分别为 2 5 3 8和 68 92。通过建立抗性品系、田间种群和敏感品系的生命表 ,发现抗性品系适合度显著下降 ,而且R2 品系下降的幅度明显大于R1品系。存在显著变化的因素有低龄若虫存活率、成虫羽化率、交配率、产卵量和孵化率下降 ,雌虫寿命缩短 ;R2 品系还表现为卵历期延长 ,3龄若虫至 5龄若虫存活率下降。R2 品系产卵高峰期迟 ,高峰期日虫量显著低于敏感品系和田间种群。用种群数量趋势指数 (I)来确定抗性品系的相对生物适合度 ,发现与敏感性品系相比 ,R1品系和R2 品系的相对适合度分别为0 60 9和 0 2 45。     

棉铃虫对氰戊菊酯抗性品系和敏感品系的相对适合度

通过构建棉铃虫Helicoverpa armigera(Hubner)对氰戊菊酯抗性品系(Fen-R)和敏感品系(S)的实验种群生命表,比较了一系列生长发育和繁殖特征,并用净增殖率(Rn)来确定两个品系的相对适合度。 结果表明,Fen-R品系与敏感品系相比具有一定程度的繁殖不利性,包括雌蛾交配率降低,每头雌蛾的平均产卵量减少以及较低的卵孵化率;没有观察到Fen-R品系在生长发育上的不利性。Fen-R品系相对于敏感品系具有0.69的适合度。     

SELECTION OF RESISTANCE STRAINS IN LIPOSCELIS BOSTRYCHOPHILA BADONNEL TO CO2-ENRICHED ATMOSPHERES*

Abstract Adults of the psocid Liposcelis bostrychophila Badonnel were exposed to atmospheres containing 35% and 55% CO₂ for 30 generations to select strains resistant to high CO₂ content (HCC). Selection pressure was maintained at around 70% of mortality. At the 30th generation, comparison of sensitivities between the selected strains (HCC₁ and HCC₂) and the original susceptible strain (MA-S) revealed a resistance factor (RF) at the 50% mortality level (LT₅₀) of 4. 6-and 5. 3-folds, respectively. Throughout the selection process, log-time against probit-mortality lines remained roughly parallel and the slopes remained lower than that of MA-S strain until the last generation. It is inplied that the genetic potential of L. bostrychophila to develop resistance to CO₂ was not exhausted until the 30th generation. Removal of selection pressure for 5 generations from 2 sub-populations of two selected strains from the 25th generation caused significant reduction in resistance. In the absence of MAs exposure, the two selected strains (HCC₁ and HCC₂) possessed the fitness defect. HCC₁ and HCC₂ were calculated by R₀ to have a fitness value of 0. 52 and 0. 45 relative to MA-S.     

SOME BIOCHEMICAL ASPECTS OF RESISTANCE TO CONTROLLED ATMOSPHERE IN LIPOSCELIS BOSTRYCHOPHILA BADONNEL (POSCOPTERA: LIPOSCELIDIDAE)*

Abstract Adults of the psocid Liposcelis bostrychophila were exposed to an atmosphere containing 35% CO₂ and 1% O₂ for 30 successive generations at 28 C and 70%–80% RH in order to select a resistant strain to controlled atmosphere (CA). At the 30th generation the resistance factor (LT₅₀ for selected generation / LT₅₀ for non-selected generation) reached to 5. 6-folds. The results of biochemical assays showed that the activities of carboxylesterase (CarE) and superoxide dismutase (SOD) in vitro increased considerably from generation to generation during the selection process, and they were closely correlated with the resistance levels. At the 30th generation, the CarE and SOD activities in the resistant strain to CA (CA-R) were 4. 06-and 5. 22-folds as much as those in the susceptible strain to CA (CA-S), respectively. Exposure to CA resulted in decrease in CarE activity; however, the decreasing range for CA-S was significantly greater than that for CA-R. CA had induction effect on SOD within short time, but for CA-R the induction time was longer and activity induced was higher than CA-S. Catalase (CAT) activity was also raised with the resistance development, but no statistical relationship was found between CAT activity and CA resistance. No significant difference of both acid phosphatase (ACP) and alkaline phosphatase (ALP) was found in CA-R and CA-S during the selection process. Peroxidase (POD) activity was not detected in L. bostrychophila. These suggest that the major mechanism responsible for CA resistance appears to be the enhanced CarE and SOD activities, and probably CAT plays an additionary role to adopt low O₂ concentration in CA resistance.     

Toxicological and biochemical characterizations of GSTs in Liposcelis bostrychophila Badonnel (Psocop., Liposcelididae)

Abstract: The toxicological and biochemical characteristics of glutathione S‐transferases (GSTs) in the resistant and susceptible strains of Liposcelis bostrychophila were investigated. The two resistant strains were the dichlorvos‐resistant strain (DDVP‐R) and PH₃‐resistant strain (PH₃‐R), and the resistance factors were 22.36 and 4.51, respectively. Compared with their susceptible counterparts, the activities per insect and specific activities of GSTs in DDVP‐R and PH₃‐R were significantly higher. The apparent Michaelis–Menten constant values (K_m) for 1‐chloro‐2,4‐dinitrobenzene (CDNB) were obviously lower in DDVP‐R and PH₃‐R (i.e. lower K_m values, 1.5625 mm for DDVP‐R and 0.6230 mm for PH₃‐R) when compared with their susceptible counterpart (K_m = 3.5520), indicating a higher affinity to the substrate CDNB in resistant strains. In contrast, the catalytic activity of GSTs towards CDNB in the susceptible strain was significantly higher than those in resistant strains. It was noticeable that when reduced glutathione (GSH) was used as substrate, GSTs from resistant strains both indicated a significantly declined affinity. For the catalytic activity of GSTs towards GSH, only the V_max value in DDVP‐R increased significantly compared with that from the susceptible strain, suggesting an overexpression of GST in this resistant strain. The inhibition kinetics of insecticides to GSTs in vitro revealed that dichlorvos and paraoxon possessed excellent inhibition effects on GSTs. The susceptible strain showed higher sensitivity (I₅₀ = 0.9004 mm ) to dichlorvos than DDVP‐R and PH₃‐R (higher I₅₀s, 8.0955 mm for DDVP‐R and 9.3346 mm for PH₃‐R). As for paraoxon, there was a similar situation. The resistant strains both suggested a higher I₅₀ (1.8735 mm for DDVP‐R, and 0.4291 mm for PH₃‐R) compared with the susceptible strain (0.2943 mm ). These suggested that an elevated detoxification ability of GSTs developed in the resistant strains.     

嗜卷书虱气调抗性形成过程中能源物质的积累与利用

报道了嗜卷书虱对高二氧化碳,低氧气调抗性形成过程中能源物质的积累以及抗性形成后在气调胁迫下能源物质的利用情况。结果表明随着抗性水平的提高。嗜卷书虱体内甘油三酯,多糖以及游离氨基酸含量均显升高。在气调胁迫环境下,嗜卷书虱抗性品系能源物质的消耗率明显低于敏感品系,甘油三酯的积累以及在气调摁迫下缓慢消耗可能是其抗气调性的主要内在机理之一。     

江苏太湖地区几种种植制度的能量转换状况

江苏太湖地区是全国主要高产粮区之一,建国以来,农业生产更有较大发展,但近年来出现了人多与地少、粮食与多种经营、用地与养地、增产与增收、提高生产水平与能源供应、提高劳动生产率与剩余劳力安排等矛盾。用生态系统的观点与综合分析的方法,从整体和全局上认识与解决这些矛盾,就是本研     

不同食物对嗜卷书虱发育和繁殖的影响

通过单头饲养方法综合比较了嗜卷书虱取食９种基本食物或食物组合的发育和繁殖情况,结果表明全麦粉最有利于该虫的发育和繁殖;在全麦粉中加入少量酵母粉和脱脂奶粉后,该虫发育明显加快、存活率及繁殖力均显著提高。此外还就该虫嗜食不同食物的原因进行了探讨。