松阿扁叶蜂越冬幼虫体内抗寒物质分析

用高效液相色谱法、氨基酸分析法、分光光度法等测定了不同时期松阿扁叶蜂AcantholydaposticalisMatsumura越冬幼虫体内抗寒物质含量,结果显示越冬期较越冬初期小分子碳水化合物、血淋巴丙氨酸、甘油、糖蛋白含量均有明显增加,依次增加了105,95,210和81%;而蛋白质、脂肪含量分别下降了16%,15%。据此认为越冬幼虫的抗寒物质系统为:小分子碳水化合物—丙氨酸—甘油—糖蛋白。     

不同寄主上桃蛀螟越冬幼虫体内生化物质变化与抗寒性研究

为预测不同寄主植物上桃蛀螟Conogethes punctiferalis(Guenée)越冬种群的变化,研究了幼虫期取食玉米、高粱和向日葵的桃蛀螟越冬幼虫体内水分和脂肪及血淋巴小分子糖(醇)与抗寒性的关系。与取食高粱和向日葵相比,取食玉米的桃蛀螟幼虫生长发育更好,越冬幼虫体重、脂肪含量显著高于前二者,降低体内含水量时期显著早,12月上旬为74.0%,而前者为82.3%和84.6%,过冷却点显著低。初冬和初春,3种寄主植物上桃蛀螟越冬幼虫的过冷缺点没有显著差异。然而隆冬季节,玉米上越冬幼虫的过冷缺点最低(-17.74℃),其次是高粱(-14.62℃),向日葵的最高(-11.68℃)。这说明,寄主植物对幼虫的生长发育、越冬物质储备及含水量有显著的影响,从而影响了滞育幼虫的抗寒能力。越冬幼虫血淋巴中小分子糖(醇)主要有海藻糖、甘油、肌醇、葡萄糖、山梨醇、半乳糖和甘露糖等。从初冬到隆冬,幼虫体内甘油含量显著上升,提高了15～101.8倍,而葡萄糖的含量变化则相反,越冬幼虫体内甘油含量变化与其抗寒能力的变化一致,说明甘油是越冬幼虫提高抗寒能力的重要物质,而合成甘油需要葡萄糖。     

松阿扁叶蜂越冬幼虫体内氨基酸含量的测定分析

本文测定了不同时期松阿扁叶蜂Acantholyda posticalis Matsumura越冬幼虫虫体、血淋。巴内氨基酸含量,并对影响幼虫抗寒的氨基酸进行了探讨。对越冬幼虫体内17种氨基酸的研究结果表明,从越冬初期至越冬期,氨基酸种类并没有发生变化,但各种氨基酸含量变化不同,丙氨酸、谷氨酸、脯氨酸、精氨酸和胱氨酸随着温度的下降呈增加趋势。幼虫虫体总氨基酸含量增幅最大的为丙氨酸,比越冬初期增加了28.8%,其次是脯氨酸、酪氨酸、苯丙氨酸,分别比越冬初期增加了9.4%、6.4%和5.4%,其他氨基酸增加不明显;幼虫血淋巴内游离氨基酸中的丙氨酸、胱氨酸和谷氨酸含量分别比越冬初期增加了94.6%、80.2%和19.6%。因此认为体内这些氨基酸含量的变化可能与低温抗寒密切相关。     

红脂大小蠹幼虫和成虫耐寒能力及耐寒物质的研究

为明确红脂大小蠹Dendroctonus valens LeConte的耐寒能力以及主要耐寒物质,对越冬期幼虫和成虫的过冷却点及冰点进行了测定,同时对越冬期及非越冬期幼虫和成虫体内的抗冻保护物质进行了测定.结果表明,越冬期幼虫和成虫的过冷却点差异不显著,分别为-18.34±0.26℃和-18.59±0.63℃,冰点差异显著,分别为-10.17±0.36℃和-15.90±0.70.越冬期幼虫体内脂肪、甘油、海藻糖和山梨醇含量均显著高于非越冬期幼虫,水分、糖原和蛋白质含量差异不显著;越冬期成虫体内糖原、甘油、海藻糖和山梨醇含量均显著高于非越冬期成虫,水分、脂肪和蛋白质含量差异不显著.甘油、海藻糖、山梨醇是红脂大小蠹幼虫和成虫的主要抗冻保护物质,在越冬过程中发挥重要作用;此外,脂肪在红脂大小蠹幼虫越冬过程中也发挥重要作用,糖原在红脂大小蠹成虫越冬过程中发挥重要作用.     

低温和光周期对西藏飞蝗体内物质的影响

为探讨西藏飞蝗对环境的适应机制,本文采用全光照(24L/0D)、全黑暗(0L/24D)与5 ℃低温相结合的试验处理,研究了低温和光照胁迫对西藏飞蝗体内物质含量变化的影响.结果表明： 西藏飞蝗虫体脂肪含量以未经低温胁迫的全光照处理最高,达到11.8%.经低温和黑暗处理的西藏飞蝗虫体脂肪含量最低,为4.7%.经低温胁迫处理后虫体的海藻糖、甘露醇以和山梨醇含量显著高于未经低温胁迫处理.虫体糖原含量以未经低温胁迫的全光照处理最高,达6.40 mg·g^-1.低温和黑暗处理还诱导丙氨酸、谷氨酸、赖氨酸和苯丙氨酸累积,促使西藏飞蝗体内多种氨基酸、甘油、小分子碳水化合物积累,糖原和脂肪含量降低.     

高温对家蚕三品系血淋巴中糖水平的影响（英文）

家蚕Bombyx mori的两个二化性品系热耐受型NB4D2和热敏感型CSR2均适合于温带气候,而多化性的PM（Pure Mysore) 品系适合于热带气候,将这3种品系5龄幼虫分别置于32℃和36℃的高温下,观察高温对其5龄幼虫至蛹期血淋巴中糖含量及海藻糖酶活性的影响。结果表明： PM幼虫和蛹的死亡率均小于NB4D2和CSR2。在蜕皮期间血淋巴海藻糖水平较高,而葡萄糖水平及海藻糖酶活性较低。32℃和36℃的高温下,幼虫蜕皮期间血淋巴中糖含量及海藻糖酶活性仅在其各自的水平上表现为小幅度的增加。蜕皮后幼虫血淋巴中海藻糖含量显著下降,而葡萄糖含量和海藻糖酶活性显著上升。在较高温度下,蜕皮后幼虫血淋巴中海藻糖含量下降幅度更大,而葡萄糖含量及海藻糖酶活性上升水平也更加显著。25±1℃下取食幼虫血淋巴中葡萄糖含量显著下降,海藻糖含量显著上升;3℃和36℃下PM 和NB4D2取食幼虫血淋巴葡萄糖和海藻糖含量以及海藻糖酶活性增加,而CSR2均减少或降低。吐丝幼虫血淋巴中葡萄糖含量及海藻糖酶活性显著下降,海藻糖小幅度下降。而在较高温度下,耐热型PM 和NB4D2吐丝家蚕血淋巴糖含量含量和海藻糖酶活性明显增加,而热敏感型CSR2的则明显下降。这3种品系蛹发育期的血淋巴糖含量及海藻糖酶活性均下降。在两较高温度下,PM蛹期血淋巴糖和海藻糖酶活性增加,而NB4D2 36℃时增加幅度小于32℃时。对于CSR2,32℃时观察到其血淋巴葡萄糖含量增加,但当环境温度增加到36℃时其血淋巴葡萄糖含量降至正常水平下。然而,当CSR2的蛹置于32℃和36℃时血淋巴海藻糖含量及其酶活性下降,且36℃时下降幅度更大。因此,桑蚕对高温的适应取决于家蚕的品系及发育阶段,并可通过其血淋巴糖及海藻糖酶活性水平进行验证。     

轮纹异痂蝗卵的过冷却能力与其体内水分和生化物质含量的关系

【目的】低温是影响昆虫生长发育和存活的关键因子之一。为明确轮纹异痂蝗Bryodemella tuberculatum dilutum卵的抗寒性及其机理, 研究了其过冷却能力与其体内水分及其他抗寒性相关生化物质含量的关系。【方法】采用热电偶法测定了轮纹异痂蝗卵的过冷却点,同时采用烘干法、残余法、氨基酸自动分析仪和高效液相色谱法分别测定了其卵的含水量、脂肪、氨基酸及小分子糖醇的含量。【结果】土壤含水量对轮纹异痂蝗滞育前卵的含水量、脂肪含量（鲜重）及过冷却点有极显著的影响(P<0.01)。随着土壤含水量从4%增加到13%,卵含水量从45.12%上升到55.25%,卵脂肪含量（鲜重）从10.39%下降到9.39%,而过冷却点从-30.11℃上升到-25.69℃。不同发育阶段卵的过冷却点、含水量、脂肪、氨基酸及小分子糖醇含量存在极显著差异(P<0.01)。从卵产下当天至120 d,卵过冷却点从-26.78℃下降至-30.18℃,含水量从51.93%下降至46.69%,脂肪含量分别从9.99%（鲜重）和17.37%（干重）上升至13.92%(鲜重)和25.29%（干重）。滞育卵的过冷却点显著低于滞育前卵的过冷却点。从卵中共检测到17种氨基酸,其中5种与过冷却点存在显著的相关关系(P<0.05)。卵过冷却点随着甘氨酸和脯氨酸含量的升高而降低,而随着胱氨酸、亮氨酸及天冬氨酸含量的增加而升高。随着卵的发育,海藻糖、甘油、肌醇和山梨醇含量逐渐上升,而葡萄糖和果糖含量逐渐下降。在卵发育过程中,海藻糖和甘油的含量显著高于其他4种物质的含量。卵过冷却点与上述6种小分子糖醇均存在显著的相关关系,其中与海藻糖和葡萄糖的相关性最强。过冷却点随海藻糖、甘油、肌醇和山梨醇含量的升高而降低,而随葡萄糖和果糖含量的升高而上升。【结论】轮纹异痂蝗卵在发育过程中,通过降低含水量,积累脂肪、脯氨酸、甘氨酸及海藻糖、甘油、肌醇和山梨醇等抗寒物质,从而提高其过冷却能力。     

温度胁迫对二化螟滞育幼虫生理指标的影响

为从生理生化水平上探讨二化螟滞育幼虫应对温度胁迫的生理机制,分别对系列温度胁迫(STS)和梯度温度胁迫(GTS)处理后的幼虫水、脂质、总糖、小分子碳水化合物含量及超氧化物歧化酶(SOD)、过氧化物酶(POD)、过氧化氢酶(CAT)活性进行了测定.结果表明:随着温度的降低,两种处理二化螟滞育幼虫虫体含水量趋于减少,且0℃以下时GTS处理下降幅度较STS处理显著;两种处理脂质含量均逐步下降且二者间无显著差异;两种处理总糖含量分别先减后增和持续下降,均检测出4种小分子碳水化合物,其中STS处理葡萄糖、甘油和果糖含量先增后减,海藻糖含量变化与此相反,而GTS处理海藻糖含量先减后增,葡萄糖和甘油含量呈相反变化,果糖含量无变化;14～-14℃范围内STS处理SOD和POD活性较GTS处理低,CAT活性相反.二化螟滞育幼虫生理指标的变化反映了其应对不同温度胁迫的生理响应.     

冷驯化对油松毛虫越冬幼虫过冷却点及主要耐寒物质的影响

【目的】冷驯化可增强昆虫的耐寒性,本文研究旨在明确不同冷驯化条件下油松毛虫Dendrolimus tabulaeformis Tsai et Liu越冬幼虫的过冷却点和主要耐寒物质的变化规律。【方法】利用热电偶方法测定越冬幼虫的过冷却点,分别采用差量法、氯仿甲醇法、苯酚硫酸法及毛细管气相测谱法测定其含水率、脂肪、糖原和小分子糖醇的含量。【结果】冷驯化会导致幼虫含水率显著降低;过冷却点和脂肪含量在低于环境气温5℃冷驯化后显著降低,当驯化温度低于环境气温10℃及以上则升高;糖原含量在9月份显著增加,越冬中期(1、3月份)含量略有降低但不显著;小分子糖醇含量的变化均不显著;海藻糖含量略降低;甘油、葡萄糖和半乳糖含量在低于环境气温5℃冷驯化后略降低,低于环境气温10℃冷驯化则升高。【结论】冷驯化使幼虫虫体含水率和脂肪含量降低,糖原含量提高,从而导致其过冷却点降低,耐寒能力提高;冷驯化的温度和时间均会影响其过冷却能力,在最适合的温度和时长可以最大程度提高其耐寒能力。研究结果为揭示油松毛幼虫的耐寒机制及潜在分布区预测提供了科学依据。     

白蜡虫及其寄主植物游离氨基酸的研究

作者研究了白蜡虫越冬前后体内游离氨基酸的组成及变化 ,并通过对虫体、蜜露及被寄生植物游离氨基酸含量及百分率组成进行对比分析 ,探讨了白蜡虫对游离氨基酸的利用问题。虫体含量较高的氨基酸有丙氨酸、谷氨酸、苏氨酸、丝氨酸、缬氨酸。大部分氨基酸及其总量在越冬期下降 ,越冬以后升高 ,逐渐超过越冬前水平。虫体大量吸收的氨基酸是丙氨酸 ,利用较少的氨基酸是天门冬氨酸 ,其它氨基酸或多或少地为白蜡虫所利用。     

Energy Allocation Changes in Overwintering Adults of the Common Pistachio Psylla, Agonoscena pistaciae Burckhardt & Lauterer (Hemiptera: Psyllidae)

The common pistachio psylla, Agonoscena pistaciae Burckhardt & Lauterer (Hemiptera: Psyllidae), is known as the key pest of pistachio orchards in Iran. This pest passes the winter as adults. In this study, energy allocation changes in relation to ambient temperature were investigated in field-collected adults by measuring total body sugar, trehalose, glucose, sorbitol, myoinositol, glycogen, lipid, and protein contents. Glycogen content decreased with decrease in ambient temperature. The decrease in glycogen content was proportional to the increase in total body sugar, trehalose, myoinositol, and sorbitol contents. In January, with mean ambient temperature of 5.4°C, glycogen content was at the lowest level, whereas total body sugar, trehalose, glucose, and sorbitol were at the highest level. Total body sugar, trehalose, myoinositol, and sorbitol contents increased as temperature decreased from 22.7°C in October to 5.4°C in January. In conclusion, low molecular weight carbohydrates and polyols may play a role in winter survival and adaptation to cold of the common pistachio psylla by providing the required cryoprotection. Also, overwintering adults of the common pistachio psylla may store energy in the form of lipid for later utilization during the overwintering.     

Effects of larval host plants on over-wintering preparedness and survival of the cotton bollworm, Helicoverpa armigera (Hübner) (Lepidoptera: Noctuidae)

Laboratory colonies of cotton bollworm larvae, Helicoverpa armigera, kept at 20 degrees C under a photoperiod of L:D=10:14 were fed on five host plants (cotton, corn, kidney bean, tobacco and tomato) and an artificial diet (control) to determine the effects of larval host quality on survival and pupal over-wintering preparedness. A separate experiment showed that diapausing pupae weighed more and contained greater nutrient stores than did non-diapausing pupae. Diapausing pupae reared on different host plants showed significant differences in terms of over-wintering reserve storage, and degree of cold-hardiness (extent of low-molecular-weight substances and SCPs), and survivorship. The more nutrients the host plant had, the more the pupae weighed and the higher the levels of total lipids and glycogen. Body water content was also significantly affected by larval food quality. The mean pupal super-cooling capacities varied significantly from -16.7 to -18.9 degrees C according to host plants the larvae feed on, and these significantly related to water content, pupal weight, lipid and glycogen content, and the levels of glycerol. Levels of trehalose, glycerol, and inositol, which were mainly low-molecular-weight substances, showed no significant differences among different host plants, except for trehalose. Pupal mortality varied from 39.7% on corn to 3.3% on the artificial diet, which was significantly related to pupal weight, total lipid content, trehalose levels, and super-cooling points. These results suggest that larval food quality can affect survival and influence the over-wintering preparedness of the cotton bollworm.     

Factors affecting carbohydrate and free amino acid content in overwintering larvae of Enosima leucotaeniella

Amounts of several metabolites were measured in overwintering larvae of Enosima leucotaeniella acclimated to temperatures between -5 and 15 degrees C for 30days. In the diapausing stage, cold hardiness, as shown by the survival rate, began rising below 15 degrees C. Glycogen content decreased as the temperature decreased from 10 to 0 degrees C. Trehalose content rose as the temperature decreased from 15 to 5 degrees C, but remained unchanged as the temperature decreased from 5 and 0 degrees C. Twenty-eight free amino acids were detected in the haemolymph; levels of proline, glutamine and glutamic acid increased at high temperatures, but alanine increased at low temperatures, especially as temperature decreased from 5 to 0 degrees C. Lipid content was unchanged by the different acclimation temperatures. The effects of temperature, diapause and aerobic conditions on the levels of carbohydrates and amino acids in overwintering larvae were analyzed. Alanine levels rose at low temperature only when the larvae were in the diapausing stage. The level of trehalose rose at low temperature in both the diapausing and post-diapausing stages, although it was higher at aerobic conditions in the post-diapausing stage. These results suggest that efficient trehalose synthesis occurs under the combination of low temperature and aerobic conditions of the post-diapausing stage, so that cold hardiness in overwintering E. leucotaeniella larvae may rise to a high level in winter.     

寄主植物对甜菜夜蛾三龄幼虫抗寒力的影响

寄主植物是影响昆虫抗寒性的主要因子之一。研究了不同温度下甜菜夜蛾Spodoptera exigua(Hübner)3龄幼虫取食小白菜、甘蓝、葱和菠菜后,对过冷却能力和体内冷冻保护剂的影响。结果表明,寄主植物对甜菜夜蛾3龄幼虫的过冷却能力有显著性影响,其中以取食甘蓝的幼虫过冷却点最低。温度和寄主植物对其过冷却点、结冰点和虫体含水量有明显的交互作用。寄主植物对其体内的海藻糖含量有显著性影响,而对甘油和糖原含量没有显著性影响。温度和寄主植物仅对海藻糖含量有显著的交互作用。随着温度的升高,取食不同寄主的幼虫体内海藻糖和糖原含量的变化趋势完全相反,认为海藻糖是由糖原转化而来。研究结果提示冬季合适的寄主植物有利于甜菜夜蛾低龄幼虫越冬。     

Study on the physiology of diapause, cold hardiness and supercooling point of overwintering pupae of the pistachio fruit hull borer, Arimania comaroffi

The pistachio fruit hull borer, Arimania comaroffi (Ragonot) (Lepidoptera: Pyralidae), is a key pest of pistachio orchards in Iran. This pest passes the winter as diapausing pupae. In this study, some physiological changes in relation to environmental temperature were investigated in field collected pupae. The relationship between supercooling point, cold hardiness and physiological changes of a wild population of this pest was also investigated. The glycogen content decreased with decrease in environmental temperature. Decrease in glycogen content was proportional to increase in total body sugar, trehalose, myo-inositol and sorbitol contents. In January with mean ambient temperature of 5.4°C, glycogen (5 mg/g fresh body weight) content was at the lowest level whereas total body sugar (10.3 mg/g fresh body weight), trehalose (8.6 mg/g fresh body weight), myo-inositol (5.3 mg/g fresh body weight) and sorbitol (2.6 mg/g fresh body weight) were at the highest levels. Total body sugar, trehalose, myo-inositol and sorbitol contents increased as mean temperature decreased from 22.7°C in October to 5.4°C in January. Total body lipid decreased during overwintering and reached to the lowest level at the end of March. Supercooling points were decreased from October to January and reached to the lowest level (-16°C) in January with minimum ambient temperature of -10°C. Survival at low temperature after 24 h was also greatest in January with 72% survival at -10°C, 39% survival at -15°C and 0% survival at -20°C. Increase in temperature from February onward, was proportional with increase in supercooling points and decrease in survival rate. Regardless of sampling date, all pupae died after 24 h at -20°C, whereas none pupae died after 24 h at -5°C. This indicates that this insect is freeze-intolerant.     

抗寒类蛋白与冷驯化诱发昆虫耐寒性研究进展

昆虫是变温动物,温度对其生长发育、基本行为及进化途径都会产生很大的影响,种群的繁衍面临如何安全度过漫长而寒冷的冬季的挑战。通过长时间的进化,昆虫获得一系列完整的耐寒策略。绝大多数的昆虫都是耐寒昆虫,在陆地寒冷温度刺激下,昆虫受抗寒基因的调控,体内产生大量抗寒物质,如海藻糖、甘油、山梨醇、抗冻蛋白、热激蛋白等,提高昆虫的耐寒能力,使其得以在低温寒冷的条件下成功越冬。同样,经过冷驯化后的昆虫能显著提高昆虫的耐寒力。近年来,关于昆虫耐寒性、抗寒类蛋白的研究不断开展,研究内容涉及昆虫的耐寒性、抗寒基因HSPs和AFPs的调控、冷驯化诱导抗寒等方面。本文综述了昆虫耐寒性、主要耐寒策略及冷驯化诱发昆虫耐寒性增强等研究内容。有助于全面认识昆虫耐寒性及其作用机制,为天敌昆虫低温储存和提高生物防治等应用打下坚实的基础。     

Geographic differences on accumulation of sugars and polyols in locust eggs in response to cold acclimation

The accumulation of low molecular weight sugars and polyols is one of major mechanisms hypothesized to increase cold tolerance in overwintering insects. But little is known about whether these sugars and polyols are involved in geographic variation of cold tolerance. In this study, we investigated accumulation patterns of eight low molecular weight sugars and polyols of eggs in tropical and temperate populations of the migratory locust, which exhibits between-population variation in cold tolerance, in response to cold acclimation (5, 0 and −5 °C). Excluding erythritol, the other seven carbohydrates were identified as possible cryoprotectants in locust eggs. Basal maximal and minimal concentrations were 45 μg/g wet weight for trehalose and 0.59 μg/g wet weight for glycerol. Most sugars and polyols were elevated after a −5 °C exposure. In a tropical population, fructose, glucose, sorbitol and myo-inositol were significantly accumulated by low temperature treatments, but glycerol was not. In the temperate population, glycerol, glucose, mannitol, sorbitol, myo-inositol were significantly accumulated but trehalose did not increase. Our results suggest different accumulation patterns of these carbohydrates of locust eggs between tropical and temperate populations and highlighted possible roles for them in geographic variation of cold tolerance in the migratory locust.     

The ontogeny of cold tolerance in the gall fly, Eurosta solidagensis

The lower lethal temperature of many insects indicates an overwintering flexibility as a result of either extensive supercooling or production of cryoprotectants. Ontogenetically, the gall fly (Eurosta solidagensis) utilizes both means of seasonal cryoprotection. All stages except third instar larvae demonstrate supercooling points well below the lowest temperature normally experienced by that particular stage. The third instar larvae exhibit a high supercooling point but are well protected by a cryoprotectant system consisting of glycerol, sorbitol, and trehalose. Glycerol is accumulated, possibly from triglyceride sources, during early autumn and reaches plateau levels (0·6 M) by early winter. Sorbitol synthesis is delayed until freezing exposures and reaches a plateau with glycerol at 0·3 M. It is not until mid-winter that peak trehalose levels are reached (300 mg %). All cryoprotectant levels are a reflection of haemolymph concentrations.Laboratory acclimation experiments further quantify these results. Trehalose synthesis is time and temperature dependent and appears to be affected by developmental processes.