Physiological and biochemical aspects of flight metabolism in cocoon-enclosed adults of the fruit beetle,Pachnoda sinuata

We studied several aspects of flight metabolism in cocoon-enclosed adults of the fruit beetle Pachnoda to investigate their flight capability. The majority of adults which were forcefully removed from their pupal cocoon flew off within 5 min of exposure to bright sunlight. Most of the beetles which did not fly voluntarily were, however, capable of flight. Compared with 2-4 week old adults of the same species, cocoon-enclosed adults have higher reserves of glycogen in flight muscles and fat body, whereas the level of total carbohydrates in the haemolymph and the concentration of proline in haemolymph, flight muscles and fat body were similar.Enzymes involved in carbohydrate breakdown (MDH, GAPDH) were more active in flight muscles and fat body of cocoon-enclosed adults compared with adults, while enzymes of proline metabolism in the flight muscles (AlaT, NAD-ME) and fat body (AlaT, NADP-ME) had similar activities in cocoon-enclosed adults and adults. An enzyme of the beta-oxidation of fatty acids (HOAD) had similar activities in flight muscles and fat body of cocoon-enclosed adults and adults.Mitochondria isolated from flight muscles of adults removed prematurely from their cocoon favour the oxidation of proline and pyruvate. Pyruvate, however, is oxidized at higher rates than by mitochondria isolated from flight muscles of adults.During a short lift-generating flight, cocoon-enclosed adults proved that their flight muscles are capable of strong flight performance. During these flights, cocoon-enclosed adults consume proline and carbohydrates at a similar rate to that of adults.The endogenous AKH peptide, Mem-CC, has hyperprolinaemic and hypertrehalosaemic activity in cocoon-enclosed adults. The hypertrehalosaemic effect, however, is stronger in cocoon-enclosed adults than in adults.The content of Mem-CC in corpora cardiaca of larvae (3rd instar), cocoon-enclosed adults and 1 day-old adults is similar at 5-6 pmol per pair of corpora cardiaca, whereas it is higher in 10 day-old adults and 20 day-old adults (37 and 15 pmol per pair corpora cardiaca, respectively).From these results we conclude that cocoon-enclosed adults comply with all the prerequisites for flight performance before they leave their pupal cocoon. Furthermore, cocoon-enclosed adults have a more pronounced carbohydrate-based metabolism before they leave their cocoon compared with adults, which suggests that carbohydrate breakdown is mainly involved in such activities as leaving the cocoon and burrowing activity thereafter.     

烟粉虱MEAM1和MED成虫在辣椒上传播番茄褪绿病毒的特性

【目的】分析与比较烟粉虱Bemisia tabaci MEAM1和MED成虫在辣椒Capsicum annuum植株上对番茄褪绿病毒(tomato chlorosis virus, ToCV)的传播差异,解析媒介昆虫-病毒-寄主植物间的互作关系,为田间辣椒上ToCV防治提供参考。【方法】利用烟粉虱MEAM1和MED成虫及ToCV cDNA侵染性克隆,对烟粉虱MEAM1和MED成虫在辣椒植株上获取和传播ToCV的能力进行比较,同时比较烟粉虱MEAM1和MED成虫在健康和携带ToCV辣椒植株上的取食偏好。【结果】在感染ToCV的辣椒植株上接虫后96 h内,烟粉虱MEAM1和MED成虫体内病毒积累量逐渐增加,MED成虫获毒速度和病毒积累量均大于MEAM1成虫的,MED成虫获毒量是MEAM1成虫的1.74倍;MED成虫在辣椒植株上的传毒量明显高于MEAM1成虫,传毒量平均相差9倍,且MED成虫传毒率比MEAM1成虫高29%。MEAM1和MED成虫对健康和感染ToCV的辣椒植株的取食偏好相似,都明显倾向于取食被ToCV侵染的辣椒植株。【结论】烟粉虱MED成虫在辣椒植株上获取、传播ToCV的能力均...     

不同日龄和吊飞过程中桔小实蝇成虫飞行肌能量代谢相关酶活性的变化

【目的】明确桔小实蝇Bactrocera dorsalis(Hendel)飞行肌对能源物质的利用。【方法】通过生化方法测定了能源物质代谢相关5种酶[3-磷酸甘油醛脱氢酶(GAPDH)、3-磷酸甘油脱氢酶(GDH)、乳酸脱氢酶(LDH)、柠檬酸合酶(CS)和3-羟酰辅酶A脱氢酶(HOAD)]活性的变化。【结果】桔小实蝇成虫中所测的5种酶活性随日龄的变化而变化,4日龄GAPDH,GDH,LDH和CS活性最高,20日龄HOAD活性最高。吊飞过程中,GAPDH,GDH和CS的活性变化基本一致,随吊飞时间的延长活性逐渐升高;LDH和HOAD的活性变化雌、雄虫完全不同。雄虫LDH活性除吊飞2 h外其他时间均高于静息状态,雌虫则始终低于静息状态;雄虫HOAD活性只有吊飞24 h低于静息状态水平,而雌虫吊飞后HOAD活性一直在静息状态水平及以下波动。【结论】桔小实蝇飞行所利用的能源物质包括糖类和脂肪,以糖类能源为主。吊飞过程中,雄虫除可以进行高速有氧代谢以外,还具备一定的无氧代谢能力,而雌虫只进行有氧代谢;雄虫能利用脂肪供给能量,雌虫则几乎不动用脂肪。研究结果为进一步阐明桔小实蝇的迁飞行为机制提供了依据。     

Homing behaviour of the giant African snail,Achatina fulica (Ferussac) (Gastropoda; Pulmonata)

Homing ability ofAchatina fulica was studied in the field by mark-recapture experiments. Snails hid in resting sites in the day and crept out in the rain or at night. Young adults dispersed for longer distance than old adults. Old adults seldom changed resting sites, while young adults changed them left almost every day. It was only young adults that the study site or came in from other areas. In transfer experiments, old adults returned to the initial resting sites in 5 days. These results suggest that old adults have a homing ability, while young adults do not show it clearly. The homing ability ofA. fulica is age-dependent. These differences may be related to the maturation pattern of the reproductive organ.     

The efficacy of cognitive–behavioral therapy for older adults with ADHD: a randomized controlled trial

Older adults with ADHD exhibit significant functional impairment, yet there is little research to guide clinicians in evidence-based care of these adults. This study examined response to treatment in older adults who participated in a previous study of the efficacy of cognitive–behavioral treatment (CBT) in adult ADHD. It was hypothesized that older adults would respond less well to CBT than younger adults, given the cognitive demands of the treatment. As described in the original publication, 88 adults who met DSM-IV criteria for ADHD were randomized to receive either a manualized 12-week CBT group intervention targeting executive dysfunction or a parallel Support group. In the current study, outcomes for 26 adults, aged 50 or older, were compared with those of 55 younger adults with respect to inattentive symptoms assessed on a structured interview by a blind clinician, as well as on ratings by self and/or collateral on measures of attention, executive dysfunction, and comorbidity. Contrary to the hypothesis, older and younger adults were equally responsive to CBT on measures of attention. The older adults also responded as well to Support as to CBT on several outcome measures. The results provide preliminary evidence that CBT is an effective intervention for older adults with ADHD. The unexpected response to support highlights a possible age-specificity of effective therapeutic intervention that requires further investigation.     

Hand Dominance and Age Have Interactive Effects on Motor Cortical Representations

Older adults exhibit more bilateral motor cortical activity during unimanual task performance than young adults. Interestingly, a similar pattern is seen in young adults with reduced hand dominance. However, older adults report stronger hand dominance than young adults, making it unclear how handedness is manifested in the aging motor cortex. Here, we investigated age differences in the relationships between handedness, motor cortical organization, and interhemispheric communication speed. We hypothesized that relationships between these variables would differ for young and older adults, consistent with our recent proposal of an age-related shift in interhemispheric interactions. We mapped motor cortical representations of the right and left first dorsal interosseous muscles using transcranial magnetic stimulation (TMS) in young and older adults recruited to represent a broad range of the handedness spectrum. We also measured interhemispheric communication speed and bimanual coordination. We observed that more strongly handed older adults exhibited more ipsilateral motor activity in response to TMS; this effect was not present in young adults. Furthermore, we found opposing relationships between interhemispheric communication speed and bimanual performance in the two age groups. Thus, handedness manifests itself differently in the motor cortices of young and older adults and has interactive effects with age.     

Audio-Visual and Meaningful Semantic Context Enhancements in Older and Younger Adults

Speech perception is critical to everyday life. Oftentimes noise can degrade a speech signal; however, because of the cues available to the listener, such as visual and semantic cues, noise rarely prevents conversations from continuing. The interaction of visual and semantic cues in aiding speech perception has been studied in young adults, but the extent to which these two cues interact for older adults has not been studied. To investigate the effect of visual and semantic cues on speech perception in older and younger adults, we recruited forty-five young adults (ages 18–35) and thirty-three older adults (ages 60–90) to participate in a speech perception task. Participants were presented with semantically meaningful and anomalous sentences in audio-only and audio-visual conditions. We hypothesized that young adults would outperform older adults across SNRs, modalities, and semantic contexts. In addition, we hypothesized that both young and older adults would receive a greater benefit from a semantically meaningful context in the audio-visual relative to audio-only modality. We predicted that young adults would receive greater visual benefit in semantically meaningful contexts relative to anomalous contexts. However, we predicted that older adults could receive a greater visual benefit in either semantically meaningful or anomalous contexts. Results suggested that in the most supportive context, that is, semantically meaningful sentences presented in the audiovisual modality, older adults performed similarly to young adults. In addition, both groups received the same amount of visual and meaningful benefit. Lastly, across groups, a semantically meaningful context provided more benefit in the audio-visual modality relative to the audio-only modality, and the presence of visual cues provided more benefit in semantically meaningful contexts relative to anomalous contexts. These results suggest that older adults can perceive speech as well as younger adults when both semantic and visual cues are available to the listener.     

Heart Rate Recovery Predicts Memory Performance in Older Adults

The current study examined cardiovascular reactivity and recovery during memory testing in a sample of 28 younger and 28 older adults. Heart rate (HR) levels were measured before, during, and after a memory test (word list recall). Contrary to prediction, older adults did not have a blunted cardiovascular response to memory tasks compared to younger adults. Word list recall performance was predicted by both Age and an Age × HR recovery interaction. As expected, younger adults performed better on the word list task than older adults. In addition, older adults with better posttest HR recovery performed significantly better than older adults with poor posttest HR recovery, whereas HR recovery differences in younger adults were inconsequential. These relationships were not affected by subjective appraisals of anxiety and task difficulty. Overall, cardiac dysregulation, seen here as low HR recovery, represents an important, potentially modifiable, factor in memory performance in older adults. In addition to being beneficial to overall health, interventions designed to help older adults regulate their HR responses may help offset certain memory declines.     

Expression profiling of a diapause-specific peptide (DSP) of the leaf beetle Gastrophysa atrocyanea and silencing of DSP by double-strand RNA

A diapause-specific peptide (DSP) composed of 41 amino acid residues including 6 cysteines, has been isolated from diapausing adults of the leaf beetle Gastrophysa atrocyanea. In this study, DSP was found to be expressed primarily in diapausing adults and to a minor extent in pupae, but not in eggs, larvae, or post-diapausing adults. DSP was not induced by bacterial or fungal challenge. DSP-less adults were generated by the injection of double-stranded RNA (dsRNA) corresponding to the dsp gene into pre-diapausing adults. Gene silencing induced by dsRNA was found to be a useful tool for the analysis of DSP in diapausing adults. DSP-less adults showed similar burrowing behavior and oxygen consumption as control insects suggesting that DSP is not essential for the normal onset and maintenance of diapause.     

异色瓢虫成虫耐寒能力的季节性变化

为研究异色瓢虫Harmonia axyridis自然种群耐寒能力的季节性变化,测定了其过冷却点、体内含水量及总脂肪含量和低温存活力。结果表明：异色瓢虫成虫低温存活力呈现出明显的季节性变化,越冬前成虫的耐寒性显著强于夏季成虫和越冬后成虫。冷驯化（5℃, 5 d）可以显著提高夏季成虫的低温存活力。雌雄成虫过冷却点和体内含水量随气温的降低而降低,升高而升高。过冷却点7月份最高,分别为−7.6℃和−8.0℃;越冬中期（2008-01-15）最低,分别为−18.1℃ 和−16.9℃。雌雄成虫体内含水量9月份最高,分别为66.87%和68.01%,10月份显著降低,越冬后期（2008-02-19）最低,分别为52.94%和51.53%。越冬期间过冷却点和体内含水量显著低于其他时期。而雌雄成虫体内总脂肪含量在越冬开始就达到最高,分别为50.07%和47.93%,随后又逐渐降低,越冬期间显著高于其他时期。由此可知异色瓢虫自然种群的耐寒性呈现出明显的季节性变化,文中还就异色瓢虫自然种群耐寒性影响因素及其越冬策略进行了讨论。     

肠道细菌产酸克雷伯氏菌及其挥发性物质对斑翅果蝇成虫的引诱效果

【目的】明确肠道细菌产酸克雷伯氏菌Klebsiella oxytoca对斑翅果蝇Drosophila suzukii的引诱效果,并鉴定和验证该菌挥发性物质对斑翅果蝇成虫的引诱效果。【方法】在无寄主植物和有寄主植物（巨蜂葡萄）的条件下,测定并分析产酸克雷伯氏菌和NB培养基(对照)的上清液对斑翅果蝇成虫的诱集比例以及被引诱成虫的雌雄性比;利用气相色谱质谱联用法(HS-SPME-GC-MS)分别鉴定产酸克雷伯氏菌和NB培养基(对照)上清液中的挥发性物质,并检测浓度较高的4种产酸克雷伯氏菌挥发性物质对斑翅果蝇成虫的引诱效果。【结果】产酸克雷伯氏菌上清液对斑翅果蝇成虫具有引诱作用。其中,无寄主植物条件下,产酸克雷伯氏菌上清液对雄虫引诱作用强于对雌虫,但是在有寄主植物条件下产酸克雷伯氏菌上清液诱集的雌雄成虫数量差异不显著。在产酸克雷伯氏菌上清液中检测到21种挥发性物质,其中浓度较高的为3-甲基-1-丁醇、2-苯乙醇、乙酸异戊酯和吲哚,斑翅果蝇成虫对3-甲基-1-丁醇、2-苯乙醇和吲哚具有趋向性,而对乙酸异戊酯则有趋避性,且3-甲基-1-丁醇可吸引更多的雄虫。【结论】肠道微生物产酸克雷伯氏菌上清液可用于引诱斑翅果蝇成虫,3-甲基-1-丁醇是产酸克雷伯氏菌代谢物中引诱雄虫的重要物质。本研究为斑翅果蝇的防治提供了参考依据。     

孪斑唇瓢虫成虫对桑白蚧的捕食功能

在实验室条件下,研究孪斑唇瓢虫Chilocorus geminus Zaslavskij成虫对桑白蚧Pseudau lacaspis pentagona(Targioni-Tozzetti)各虫态的捕食功能反应,寻找效应和干扰效应。结果表明,孪斑唇瓢虫成虫对桑白蚧各虫态的功能反应均符合Holling-Ⅱ型圆盘方程。孪斑唇瓢虫成虫对桑白蚧各虫态的寻找效应随自身密度的增加而降低。根据Holling-Ⅲ型功能反应新模型拟合出1头孪斑唇瓢虫成虫对桑白蚧各虫态的最佳寻找密度分别为:成虫26.7头、卵185.2粒、1龄若虫47.9头、2龄若虫46.8头。当孪斑唇瓢虫成虫与桑白蚧各虫态的数量同比例增加时,孪斑唇瓢虫成虫个体间的相互干扰系数为0.3901,0.7891和0.9827;当桑白蚧2龄若虫数量不变而孪斑唇瓢虫成虫数量增加时,孪斑唇瓢虫成虫个体间的相互干扰系数为0.0960。     

Diferencias en función de la edad y la autopercepción del envejecimiento en ansiedad,tristeza, soledad y sintomatología comórbida ansioso-depresiva durante el confinamiento por la COVID-19

ObjectivesTo analyze differences by age group in anxiety, depression, loneliness and comorbid anxiety and depression in young people, middle aged adults and older adults during the lock-down period at home due to the COVID-19 pandemic, and to explore the association between negative self-perceptions of aging and psychological symptoms controlling by age group.MethodParticipants are 1501 people (age range 18 to 88 years). Anxiety, sadness, loneliness and self-perceptions of aging were assessed. The sample was divided according to the age group and quartiles (lower, intermediate levels, and higher) of anxiety, sadness, loneliness and self-perceptions of aging.ResultsOlder adults reported lower levels of anxiety and sadness than middle aged adults, and middle aged adults reported lower levels than younger participants. Middle aged adults reported the lowest loneliness, followed by older adults and younger participants. For each age group, those with more negative self-perceptions of aging reported higher anxiety, sadness and loneliness. More comorbid anxiety and sadness was found in younger adults and less in older adults; more depressed participants in the middle aged group, and more older adults and less younger participants were found in the group with the lowest levels of anxiety and sadness. For all the age groups, participants with high levels of comorbid anxiety and sadness are those who report the highest scores in negative self-perceptions of aging.ConclusionsOlder adults reported lower psychological anxiety, sadness and loneliness than the other age groups. Having negative self-perceptions of aging damage psychological health irrespective of the chronological age.     

Healthy older adults have insufficient hip range of motion and plantar flexor strength to walk like healthy young adults

Limited plantar flexor strength and hip extension range of motion (ROM) in older adults are believed to underlie common age-related differences in gait. However, no studies of age-related differences in gait have quantified the percentage of strength and ROM used during gait. We examined peak hip angles, hip torques and plantar flexor torques, and corresponding estimates of functional capacity utilized (FCU), which we define as the percentage of available strength or joint ROM used, in 10 young and 10 older healthy adults walking under self-selected and controlled (slow and fast) conditions. Older adults walked with about 30% smaller hip extension angle, 28% larger hip flexion angle, 34% more hip extensor torque in the slow condition, and 12% less plantar flexor torque in the fast condition than young adults. Older adults had higher FCU than young adults for hip flexion angle (47% vs. 34%) and hip extensor torque (48% vs. 27%). FCUs for plantar flexor torque (both age groups) and hip extension angle (older adults in all conditions; young adults in self-selected gait) were not significantly <100%, and were higher than for other measures examined. Older adults lacked sufficient hip extension ROM to walk with a hip extension angle as large as that of young adults. Similarly, in the fast gait condition older adults lacked the strength to match the plantar flexor torque produced by young adults. This supports the hypothesis that hip extension ROM and plantar flexor strength are limiting factors in gait and contribute to age-related differences in gait.     

Differences in faecal bacteria populations and faecal bacteria metabolism in healthy adults and celiac disease patients

Differences in the intestinal microbiota between children and adults with celiac disease (CD) have been reported; however, differences between healthy adults and adults with CD have not been clearly demonstrated. The aim of this study was to evaluate the differences in the intestinal microbiota between adults with CD and healthy individuals. Microbial communities in faecal samples were evaluated by PCR-denaturing gradient gel electrophoresis (DGGE) and gas-liquid chromatography of short chain fatty acids (SCFAs). The study group included 10 untreated CD patients, 11 treated CD patients and 11 healthy adults (in normal gluten diet and in GFD). UPGMA clustered the dominant microbial communities of healthy individuals together and separated them from the dominant microbial communities of the untreated CD patients. Most of the dominant microbial communities of the treated CD patients clustered together with those of healthy adults. The treated CD patients showed a reduction in the diversity of Lactobacillus and Bifidobacterium species. The presence of Bifidobacterium bifidum was significantly higher in untreated CD patients than healthy adults. There was a significant difference between untreated CD patients and healthy adults, as well as between treated CD patients and healthy adults, regarding acetic acid, propionic acid, butyric acid, and total SCFAs. In conclusion: healthy adults have a different faecal microbiota from that of untreated CD patients. A portion of the treated CD patients displayed a restored "normal" microbiota. The treated CD patients significantly reduce the Lactobacillus and Bifidobacterium diversity. Healthy adults have a different faecal SCFAs content from that of CD patients.     

Reduced sensitivity to immediate reward during decision-making in older than younger adults

We examined whether older adults differ from younger adults in the degree to which they favor immediate over delayed rewards during decision-making. To examine the neural correlates of age-related differences in delay discounting we acquired functional MR images while participants made decisions between smaller but sooner and larger but later monetary rewards. The behavioral results show age-related reductions in delay discounting. Less impulsive decision-making in older adults was associated with lower ventral striatal activations to immediate reward. Furthermore, older adults showed an overall higher percentage of delayed choices and reduced activity in the dorsal striatum than younger adults. This points to a reduced reward sensitivity of the dorsal striatum in older adults. Taken together, our findings indicate that less impulsive decision-making in older adults is due to a reduced sensitivity of striatal areas to reward. These age-related changes in reward sensitivity may result from transformations in dopaminergic neuromodulation with age.     

Altered coronary vascular control during cold stress in healthy older adults

Cardiovascular-related mortality increases in the cold winter months, particularly in older adults. Previously, we reported that determinants of myocardial O(2) demand, such as the rate-pressure product, increase more in older adults compared with young adults during cold stress. The aim of the present study was to determine if aging influences the coronary hemodynamic response to cold stress in humans. Transthoracic Doppler echocardiography was used to noninvasively measure peak coronary blood velocity in the left anterior descending artery before and during acute (20 min) whole body cold stress in 10 young adults (25 ± 1 yr) and 11 older healthy adults (65 ± 2 yr). Coronary vascular resistance (diastolic blood pressure/peak coronary blood velocity), coronary perfusion time fraction (coronary perfusion time/R-R interval), and left ventricular wall stress were calculated. We found that cooling (via a water-perfused suit) increased left ventricular wall stress, a primary determinant of myocardial O(2) consumption, in both young and older adults, although the magnitude of this increase was nearly twofold greater in older adults (change of 9.1 ± 3.5% vs. 17.6 ± 3.2%, P < 0.05, change from baseline in young and older adults and young vs. older adults). Despite the increased myocardial O(2) demand during cooling, coronary vasodilation (decreased coronary vascular resistance) occurred only in young adults (3.22 ± 0.23 to 2.85 ± 0.18 mmHg·cm(-1)·s(-1), P < 0.05) and not older adults (3.97 ± 0.24 to 3.79 ± 0.27 mmHg·cm(-1)·s(-1), P > 0.05). Consistent with a blunted coronary vascular response, absolute coronary perfusion time tended to decrease (P = 0.13) and coronary perfusion time fraction decreased (P < 0.05) during cooling in older adults but not young adults. Collectively, these data suggest that older adults demonstrate an altered coronary hemodynamic response to acute cold stress.     

Social behaviour of juvenile red sea urchins, Strongylocentrotus franciscanus (Agassiz)

This study examined social behaviour of juvenile red sea urchins, Strongylocentrotus franciscanus (Agassiz). At four coastal locations in British Columbia, Canada, distributions of juvenile sea urchins were examined in relation to adults. One-third of all juveniles were found underneath an adult “spine canopy”, another third outside the spine canopy but close to an adult, and the remainder were found apart from adults. Juveniles associated with adults were contagiously distributed with each other. In the laboratory, juveniles chose adults over other target locations. They selected adults in particular locations over others, and in one case showed selection among adults; but they did not select between fed and non-fed adults, nor between adults that had been “protective” and “non-protective” of juveniles in the field. In time-lapse film studies, starved juveniles showed little change in social behaviour when food was introduced, but showed a dramatic change in behaviour when predators were active. We suggest that juvenile red sea urchins are found under the spine canopies of adults as a result of juvenile behaviour; and that this interaction functions to protect juveniles from predation. The strong gregarious nature of juveniles among themselves may have evolved in a different selective situation as a defence against predation and to ensure reproductive success.     

桑天牛虫体提取物的成分及其在两性通讯中的作用

为明确桑天牛成虫释放的化学信息素成分及其在两性通讯中的作用,利用气质联用仪(GC-MS)分析了桑天牛整体及其腹末组织提取物的化学成分,采用Y型嗅觉仪测定雌雄成虫对5种主要提取物标准品的嗅觉反应,以及雌雄虫对涂抹标准品的洗脱同性与异性成虫的接触反应。结果表明: 桑天牛雌雄成虫整体及其腹末组织提取物化学成分主要为10个碳以上的烷烃和烯烃,其中顺-9-二十三碳烯含量最高,其次为二十七烷、二十九烷、十九碳烯、二十八烷和9-己基-十七烷等,以及少量醛类和酯类物质。嗅觉行为反应结果显示,二十九烷对雌雄虫的引诱作用显著,二十七烷仅对雌虫有显著的引诱作用,而十九碳烯则对雌成虫产生显著的驱避作用,1-二十二碳烯和顺-9-二十三碳烯对桑天牛雌雄虫作用不明显。接触反应结果显示,雄虫对涂抹1-二十二碳烯、二十七烷和二十九烷的洗脱成虫表现出明显的求偶行为,而雌虫仅对涂抹二十九烷的洗脱成虫表现出明显的求偶行为。综合分析发现,1-二十二碳烯、二十七烷和二十九烷是桑天牛性信息素的重要组分,在两性通讯中起重要作用。     

褐飞虱高温条件下应激反应及体内保护酶系活性的研究

利用34℃、36℃、38℃3个温度处理褐飞虱的若虫和不同型成虫,研究其在热休克过程中体内保护酶系活性及脂质过氧化物含量的变化。结果表明,热休克对4龄若虫过氧化氢酶（CAT）活性影响大于3龄、5龄,而其成虫期CAT活性则随日龄增加而增加,36℃为CAT清除H2O2最适温度。高龄若虫全内谷胱甘肽过氧化物本(GSH-px）活性高于低龄若虫,老熟成虫体内GSH－px清除H2O2能力强于初羽化成虫,超氧化物歧化酶（SOD）活性与处理温度呈正相关,而同一处理温度下SOD活性随成虫龄期和成虫日龄增加而降低,长型成虫体内CAT、GSH－px、SOD活性均高于短翅型,而雌、雄成虫间CAT、GSH－px、SOD活性无明显差异（α＞0.05）。褐飞虱体内脂质过氧化物（LPO）含量随处理温度升高而上升,同一处理温度下随若虫龄期和成虫日龄的增加而增加,短型成虫体内LPO含量高于长翅型。