亚致死剂量苏云金杆菌蜡螟亚种对大蜡螟幼虫SOD和POS活性的影响

本文研究了亚致死剂量苏云金杆菌蜡螟亚种对大蜡螟幼虫超氧化，物歧化酶和过氧化物酶的影响。结果透明，经Ｂｔ晶体处理后大蜡螟幼虫体内和幼虫肠道超氧化物歧化以及过氧化物酶活力增强，幼虫体内过氧化物酶同功酶增加一条谱带，但超氧化物歧化酶同功谱无明显变化。     

亚致死剂量苏云金杆菌蜡螟亚种对大蜡螟幼虫酯酶活力的影响

本文研究了亚致死剂量苏云金杆菌蜡螟亚种对大蜡螟幼虫以及幼虫肠道、血淋巴酯酶的影响。结果表明，经Ｂ．ｔ．晶体处理后大蜡螟整体幼虫和肠道酯酶比活力均下降，同功酶谱无明显变化；血淋巴酯酶同功酶活力及同功酶谱亦无明显变化     

亚致死剂量苏云金杆菌蜡螟亚种对大蜡螟幼虫酯酶活力的影响

本文研究了亚致死剂量苏去杆菌蜡螟亚种对大蜡螟幼虫以及幼虫肠道、血淋巴酯酶的影响。结果表明，经Ｂ．ｔ．晶体处理后大蜡螟整体幼虫和肠道酯酶比活力均下降，同功酶谱无明显变化；血淋巴酯酶同功酶活力及同功酶谱亦无明显变化。     

蜡螟绒茧蜂对大蜡螟幼虫的寄生作用

以大蜡螟的低龄幼虫为寄主,在实验室条件下对蜡螟绒茧蜂的寄生作用进行了研究。结果表明：蜡螟绒茧蜂一生最多产卵68粒,平均45.85粒。蜡螟绒茧蜂卵产于寄主体内的位置多在1～4腹节;多数在寄主体内只产1粒或2粒卵。该蜂能寄生大蜡螟1～4龄幼虫,但2～4龄幼虫同时存在时,偏爱寄生2、3龄幼虫,其选择系数分别为0.35和0.42。     

亚致死剂量苏云金杆菌蜡螟亚种对大蜡螟幼虫物质代谢的影响

本文研究了亚致死剂量苏云金杆菌蜡螟亚种(Bacillus thuringiensis galleriae)晶体蛋白对大蜡螟(Galleria mellonella)幼虫物质代谢的影响。结果表明,大蜡螟幼虫经亚致死剂量B.t.galleriae晶体蛋白处理后,中肠糖原、组蛋白及RNA的量均较正常幼虫减少。处理组幼虫整体匀浆物中可溶性蛋白质含量也较正常幼虫低。大蜡螟幼虫经B.t.galleriae晶体蛋白处理后中肠上皮细胞明显空泡化,并发生解体。     

大蜡螟防治研究初报

大蜡螟Galleria mellonella L.是蜜蜂的重要敌害之一,对中华蜜蜂Apis cerana F.危害尤重。1984～1988年,我们在研究大蜡螟生物学的基础上,根据大蜡螟产卵及幼虫上脾危害等习性,研制成一种阻隔器,安装在蜂箱前、后壁上,控制了大蜡螟幼虫上脾途径,取得了良好的防治效果。     

温度对大蜡螟生长发育和繁殖的影响

为预测大蜡螟Galleria mellonella的发生期并为其田间有效防控提供参考依据,采用室内人工恒温饲养方法,测定27、29、31、33、35℃五个温度下大蜡螟幼虫龄期、各虫态存活率和发育历期及成虫寿命和繁殖力,对其发育速率与温度进行回归分析,计算各虫态发育起点温度和有效积温。结果显示,27～35℃范围内,大蜡螟能正常发育,但低温会使幼虫龄期减少,29～35℃下大蜡螟有7～10龄幼虫,而27℃下,大蜡螟仅有6～8龄幼虫。温度显著影响各虫态存活率,低龄尤其1龄幼虫受温度的影响较大,27～33℃下其存活率低于26.06%,当温度为35℃时其存活率高达87.27%。世代及各虫态的发育历期均与温度呈负相关,卵期、幼虫期、蛹期及世代发育历期均在35℃降至最小值,分别为5.00、25.90、7.05和37.95 d。各虫态发育速率与温度符合二次回归模型。由直接最优法计算得到大蜡螟卵、幼虫、蛹及世代的发育起点温度分别为13.11、13.69、19.83和13.19℃,有效积温依次为100.32、514.09、95.13和789.87日·度。雌雄成虫的寿命和雌成虫产卵历期均随温度升高而缩短,温度...     

经低温贮存的大蜡螟幼虫对线虫侵染率及侵染强度的影响

大蜡螟（Ｇａｌｅｒｉａｍｅｌｏｎｅｌａ）幼虫对昆虫病原线虫极为敏感，又易于人工标准化饲养，因此常作为昆虫病原线虫的资源调查、活体繁殖、线虫回收和线虫毒力测定等研究的试虫。大蜡螟幼虫在真菌、细菌等其它微生物研究中也有广泛用途。在实际工作中，一次试验需用...     

大蜡螟个体生物学研究

大蜡螟Galleria mellonella L·是中华蜜蜂Apis cerana F·的主要敌害。据我们1984年1～6月在试验蜂场先后抽脾(边脾)33张剥查,其中有大蜡螟2719头,占99.02％,有小蜡螟Achroia grisella F·27头,占0.98％,平均每张巢脾有大蜡螟82.39头,给养蜂生产造成了严重的经济损失。为了给养蜂业中大蜡螟的防治研究提供理论依据,1984～1988年,代们对大蜡螟个体生物学进行了观察研究,现将结果报告如下。     

诱集植物香根草对大螟幼虫营养作用及消化酶的影响

香根草能够有效诱集水稻害虫大螟Sesamia inferens(Walker)在其上产卵,但孵化出的幼虫在香根草上不能完成生活史,香根草对大螟幼虫表现出致死作用。为明确香根草对大螟幼虫致死的作用机制,本研究分析测定了取食香根草后大螟幼虫的营养指标及体内消化酶的变化。结果表明,取食香根草能显著影响幼虫的生长效率及体内消化酶活性。与取食水稻的幼虫相比,取食香根草的幼虫粗生长效率ECI和净生长效率ECD显著降低;除蔗糖酶外,其他消化酶的活性在特定龄期呈显著下降的趋势,具体表现为4龄幼虫蛋白酶比活力、2~4龄幼虫淀粉酶比活力和1~4龄幼虫海藻糖酶比活力显著降低,而1~3龄幼虫蔗糖酶比活力显著提高。本文为进一步阐明香根草对大螟的致死作用机制奠定了基础,为开发以香根草为基础的稻螟绿色防控新技术提供了理论依据。     

抗虫绿豆对绿豆象生长发育及体内几种酶活性的影响

为明确抗虫绿豆对绿豆象Callosobruchus chinensis L.生长发育的抑制作用,采用室内人工接虫和生化测定的方法,研究了绿豆象幼虫取食抗虫绿豆后其体重、体内消化酶、保护酶和解毒酶活性及成虫羽化率和体重的变化。结果表明,取食抗虫绿豆的绿豆象幼虫体重、雌、雄成虫体重以及成虫羽化率分别是取食感虫绿豆的0.69、0.69、0.71及0.14倍;取食抗虫绿豆8~16 d的绿豆象幼虫中肠总蛋白酶、α-淀粉酶和α-葡萄糖苷酶活性均显著低于对照;保护酶超氧化物歧化酶、过氧化物酶和过氧化氢酶与解毒酶羧酸酯酶和谷胱甘肽转移酶的活性在绿豆象幼虫取食8~12 d时均显著高于对照,但取食14~16 d时,2种解毒酶活性与对照差异不显著。表明抗虫绿豆可抑制绿豆象幼虫中肠消化酶活性,影响其体内保护酶和解毒酶活性,从而使绿豆象幼虫不能正常生长发育。     

Activities of antioxidant enzymes and photosynthetic responses in tomato pre-treated by plant activators and inoculated by Xanthomonas vesicatoria

The activities of antioxidant enzymes and photosynthetic responses were investigated in tomato (Lycopersicon esculentum L. var.) pre-treated by plant activators and inoculated by Xanthomonas vesicatoria. Plants were sprayed with acibenzolar-S-methyl, ASM [Bion^® 50 WG (0.2 g l⁻¹)] and aqueous extract from dry necrotic tissue flour (VLA) of ‘Lobeira’ (Solanum lycocarpum) bush. Four days later, the plants were challenged with a virulent strain of X. vesicatoria, under greenhouse conditions. Tomato leaves were then assessed to determine the activities of the main antioxidant enzymes: superoxide dismutase (SOD), catalase (CAT), peroxidase (POX), and ascorbate peroxidase (APX). A reduction of bacterial leaf spot severity was observed in plants treated by ASM (49.3%) and VLA (31.4%), without any in vitro inhibitory activity over the pathogen. Controls showed decreases in CO₂ assimilation, transpiration, photosynthetic rates, and stomatal conductance. Water use efficiency and carboxylation efficiency were strongly affected in ASM- and VLA-treated, in comparison to controls and healthy plants. The tested substances induced increases in SOD and CAT activities in a delayed enzymatic response typical in compatible plant–pathogen interactions. Measured at daily intervals, activities of APX and POX were significantly (ρ0.05) higher in treated plants than in controls, except for APX in ASM-treated plants where no difference was found when compared to controls. Only POX was clearly induced at the earlier stages after spraying the tomato plants with ASM or VLA. Our results suggest that late increases in antioxidant enzyme activities may play a role in mitigating oxidative damage in restoring the photosynthetic imbalance imposed by the expansion of bacterial lesions.     

不同地理种群二化螟滞育和解除滞育幼虫的抗逆性酶活性比较

测定了不同地理种群二化螟滞育和非滞育幼虫的过氧化氢酶(CAT)、过氧化物酶(POD)、超氧化物歧化酶(SOD)、乳酸脱氢酶(LDH)和ATP酶的活性。不同地理种群二化螟滞育幼虫体内5种抗逆性酶的活性没有显著差异;解除滞育幼虫体内的抗逆性酶活力随着纬度的降低而上升,长沙种群的酶活性明显高于哈尔滨种群的酶活性;滞育幼虫体内CAT、POD和SOD酶活性高于解除滞育幼虫体内的酶活性,而ATP和LDH的活性解除滞育幼虫高于滞育幼虫。二化螟滞育幼虫体内酶活力的增高和下降与抗寒有着较密切的关系。不同虫态体内的5种抗逆性酶的活性测定结果显示老熟幼虫体内的CAT、POD和SOD酶活性低于蛹期,而ATP和LDH酶的活性老熟幼虫高于蛹期。     

Bioactivity of pyrogallol against melon fruit fly, <Emphasis Type="Italic">Bactrocera cucurbitae</Emphasis>

The insecticidal effects of pyrogallol were studied by treating eggs and larvae of the melon fruit fly, Bactrocera cucurbitae (Coquillett) (Tephritidae: Diptera), with various concentrations (1, 5, 25, 125, 625 and 3125 ppm) of the phenolic compound. Although egg hatching decreased following treatment of 0–8-h old eggs with pyrogallol, the decrease was not significantly different from the control. Larval period and total development period declined significantly in 64–72-h-old and 88–96-h-old B. cucurbitae larvae fed on pyrogallol-treated diet. However, in the 44–48-h-old larvae, the larval period and total development period were not affected by pyrogallol treatment at any of the tested concentrations. None of them survived up to the pupal stage at the highest concentration. Number of pupae formed and adult emergence decreased significantly in all larval instars following feeding on pyrogallol-treated diet. The analysis of enzymes in 64–72-h-old larvae treated with LC₄₀ concentration (16.21 ppm) of pyrogallol at three time intervals, i.e., 24 h, 48 h and 72 h, showed significant induction in the activities of ascorbate peroxidase (APOX) and glutathione S-transferases (GSTs) at 24 h but a decrease was observed following prolonged treatment. On the other hand, superoxide dismutase (SOD) and peroxidases (POX) activity remained suppressed during the initial treatment interval but increased with prolonged treatment in 136–144-h-old larvae. The catalase (CAT) activity was suppressed at all treatment durations whereas glutathione reductase (GR) activity was not affected by pyrogallol treatment. An increase in the activities of ascorbate peroxidase, superoxide dismutase, peroxidases and glutathione S-transferases indicates an induction of defensive response of the melon fruit fly to the toxic effects produced by ingestion of pyrogallol. Although the effects of the compound on enzyme activity were tested on second instar, it would be interesting to see the effects on other instars too.     

稻纵卷叶螟感染苏云金杆菌后的组织病理观察

采用石蜡组织切片法,观察了稻纵卷叶螟5龄幼虫感染苏云金杆菌后中肠的组织病理变化。感染2小时,幼虫中肠无明显变化;6小时,上皮细胞出现少量空泡;10小时,空泡数量增多;22小时,中肠出现溃烂现象。感染致死的虫体,中肠完全溃烂,但肠腔内含物不渗入体腔。     

菜青虫感染B.t.(HD-1)乳剂后的组织病理观察

用光学显微镜观察了青菜虫感染B.t.乳剂(湖北省农科院研制)后的组织病理变化。在30℃条件下,感染后2小时,中肠上皮细胞膨大,形成空泡;4小时以后,空泡进一步扩大,细胞质开始解体,8小时后,细胞完全崩溃脱落;感染后10小时,基底膜出现破裂,血腔中其他组织亦遭破坏,进而引起幼虫死亡。所得结果,与前人用其它昆虫试验结果基本一致。     

吡虫啉对番茄幼苗根系活力及生理生化指标的影响

本论文以70%吡虫啉水分散粒剂为研究药剂,以番茄为研究试材,通过室内盆栽法研究了不同剂量的吡虫啉对番茄植株生长量的影响,以及对番茄体内过氧化氢酶(CAT)、超氧化物歧化酶(SOD)和番茄根系活力进行了测定。结果表明70%吡虫啉水分散粒剂分别以有效成分用量1.0、1.5、2.5、3.0mg/株和5.0mg/株5个剂量处理番茄幼苗,在处理后30d测定番茄展开叶片数、株高、主根长、地上和地下部分鲜重,随着药剂浓度的增加,各测定指标呈现先升高后降低的变化趋势,其中以2.5mg/株剂量影响最大,与清水对照比差异显著。测定不同浓度的吡虫啉处理番茄后30d叶片及根系中CAT、SOD的活性和根系活力,结果表明不同剂量的吡虫啉均对番茄叶片和根系的CAT、SOD活性和根系活力有一定的影响,其效应并不是随药剂浓度的增加而增加,与清水对照比以2.5mg/株剂量各生理指标活性增加最大,超过2.5mg/株的剂量有下降趋势。     

Biological control mechanisms of D-pinitol against powdery mildew in cucumber

D-pinitol is an effective agent for controlling powdery mildew (Podosphaera xanthii) in cucumber. In this study, we determined the mechanisms of D-pinitol in controlling powdery mildew in cucumber plants. We compared P. xanthii development on cucumber leaf surface treated with D-pinitol or water (2 mg ml⁻¹) at different time points after inoculation. The germinating conidia, hyphae, and conidiophores of the pathogen were severely damaged by D-pinitol at any time of application tested. The highest level of suppression of fungal development was obtained at 3 days after inoculation. The contents of chlorophyll, total phenolics, flavonoid, and gallic acid and its derivatives (GAD); the activities of phenylalanine ammonialyase (PAL), polyphenoloxidase (PPO), peroxidase (POX), and superoxide dismutase (SOD); and the expression of the genes encoding for PR-1, peroxidase (POX), lipoxygenase (LOX1), chitinase (Chit1) were higher in the cucumber leaves treated with D-pinitol and inoculated than in the leaves either treated with D-pinitol or inoculated with the pathogen. These results suggest that D-pinitol triggers several plant defense responses in cucumber leading to pathogen suppression and resistance to powdery mildew.     

Soil applied propiconazole alleviates the impact of salinity on Catharanthus roseus by improving antioxidant status

An investigation was carried out to estimate the salt stress ameliorative effect of propiconazole (a triazole group of fungicide cum plant growth regulator) on the NaCl stressed Catharanthus roseus. The experiment was conducted in pots. All the pots were irrigated to the field capacity with ground water up to 30 days after sowing (DAS). The treatments were given as 80 mM NaCl, 80 mM NaCl + 20 mg l⁻¹ propiconazole and 20 mg l⁻¹ propiconazole alone on 30, 50 and 70 DAS. The samples were collected on 60 and 80 DAS. NaCl stress inhibited the root and stem length, total leaf area, fresh and dry weight, and antioxidant enzymes superoxide dismutase (SOD), peroxidase (POX) and polyphenol oxidase (PPO) activities. Plants treated with NaCl with propiconazole increased these parameters to a larger extent when compared to NaCl stressed plants. The propiconazole treatment increased the root length, fresh and dry weight, and SOD, POX and PPO activities, but decreased the stem length and leaf area when compared to control. The results showed that the propiconazole could significantly ameliorate the effect of NaCl stress in Catharanthus roseus.