不同性诱剂对橘小实蝇的监测作用

橘小实蝇Bactrocera dorsalis是一种世界性检疫害虫,可危害250多种水果和蔬菜。通过在湖南农业大学2hm2柑橘园开展的4种不同性诱剂对橘小实蝇的监测诱集试验结果表明：橘小实蝇对湖南农业大学橘园危害并不明显,橘小实蝇（Me）诱剂对橘小实蝇的监测效果最好,可为及时发现该虫危害、监测疫情提供依据。     

避雨对‘热农1号’杧果果实发育和采后耐贮性的影响

为掌握自然条件下阿里山潜蝇茧蜂[Fopius arisanus(Sonan)]对橘小实蝇[Bactrocera dorsalis(Hendel)]为害的控制效果，研究阿里潜蝇茧蜂与橘小实蝇数量之比对橘小实蝇卵的被寄生率的影响和阿里山潜蝇茧蜂对橘小实蝇的持续控制效果。结果表明：当阿里山潜蝇茧蜂与橘小实蝇数量之比达到3:1时，阿里山潜蝇茧蜂对橘小实蝇卵的寄生率达57%左右，再增加阿里山潜蝇茧蜂不会显著提高橘小实蝇卵的被寄生率；阿里山潜蝇茧蜂对橘小实蝇的有效控制时间为15 d左右。由此可见，田间应用阿里山潜蝇茧     

23种植物精油对橘小实蝇的行为反应研究

通过超临界 CO2 萃取技术萃取 23 种植物精油,并使用 Y 型嗅觉仪测试了 23 种植物精油对橘小实蝇雌虫的行为反应。 结果表明,当精油质量浓度为0.5％时,在5min内,番石榴果精油、黄皮果皮精油、莲雾叶精油对橘小实蝇雌成虫有明显的引诱效果;香蕉叶精油、大叶桃花心木精油、番石榴叶精油对橘小实蝇雌成虫有明显的驱避效果。     

生境及气象因子对南瓜实蝇雄成虫数量动态的影响

监测不同生境下南瓜实蝇雄成虫的数量动态,分析影响南瓜实蝇数量变动的关键气象因子。结果表明:生境和气象因子显著影响南瓜实蝇雄虫的数量动态。混合菜地、园林区以及混合果园诱集的南瓜实蝇雄虫数量多于住宅区、农贸市场、苦瓜种植地同期诱集的雄虫数;通过逐步回归分析和通径分析得出影响南瓜实蝇雄虫数量动态的气象因子有月平均气温、月平均气压、月平均相对湿度、月最小相对湿度和月日照时数,其中月平均温度是影响其数量动态的最关键气象因子。基于本研究的结果,建议对南瓜实蝇的防控应不仅仅局限在具有其寄主植物的生境,而应根据监测的数据对其他生境的南瓜实蝇进行一并治理。     

番石榴产区橘小实蝇转移为害规律研究

诸多室内研究结果表明番石榴(Psidium guajava L.)是橘小实蝇[Bactrocera dorsalis (Hendel)]最嗜好的寄主。然而,自然条件下番石榴的果实成熟期均有明显的季节性,当其采收后橘小实蝇种群如何生存和繁衍尚不明确。假设番石榴果实成熟采收前后橘小实蝇会转移为害,且其转移为害规律与气象因子紧密相关。为验证该假设,本研究选择广西番石榴主产区,调查了橘小实蝇寄主种类、为害率、转移为害规律及其与气象因子的关系。结果表明,番石榴产区不同月份成熟的13种瓜果中有10种受橘小实蝇为害,番石榴的受害率最严重,最高达84.00%;橘小实蝇的转移为害规律为番石榴和杨桃(Averrhoa carambola L.)(1—2月)→番石榴、杨桃和桑葚(Morus alba L.)(3—4月)→番石榴和香水柠檬[Citrus limon (L.) Burm. f.](5月)→番石榴、香水柠檬、莲雾[Syzygium samarangense (Bl.) Merr. et Perry]、荔枝(Litchi chinensis Sonn.)和龙眼(Dimocarpus longan Lour.)裂果(6月)→番石榴、杨桃、香水柠檬和莲雾(7—9月)→番石榴、杨桃、香水柠檬、金橘[Fortunella margarita (Lour.) Swingle]和青枣(Zizyphus mauritiana Lam.)(10—12月);番石榴产区全年均可诱捕到橘小实蝇成虫,共有5个成虫发生高峰期,分别为5月下旬、7月下旬、8月下旬至9月下旬、11月上旬和12月上旬。气温和降水量分别是影响番石榴产区橘小实蝇转移为害规律的主要和次要因子。研究结果明确了番石榴产区橘小实蝇的转移为害规律及其与气象因子的相关性,为制定其种群控制策略和防治技术提供重要参考。     

应用GF-120诱杀橘小实蝇成虫效果评价

通过室内和田间引诱试验,观察不同浓度的GF-120对橘小实蝇成虫的诱杀效果以及对雌、雄两性成虫诱杀效果的差异。结果表明:在室内,GF-120原液与水为1∶4和1∶6(V/V)混合24 h时,诱杀效果最好,1∶2时效果最差;在田间,GF-120原液与水为1∶4时诱杀效果较好,1∶10时效果较差。而在本试验处理中,对橘小实蝇雌雄虫诱杀效果均无显著性差异。     

杨桃橘小实蝇的防治试验

采用套袋、药剂、信息素诱集成虫等方法对杨桃果实上橘小实蝇进行防治试验，结果表明套袋防治效果最好，药剂防治效果较差，信息素诱集成虫有一定的防效，建议在激素诱集成虫的基础上进行套袋防治橘小实蝇。     

橘小实蝇生物学及防治研究

橘小实蝇Bactrocera dorsalis(Hendel)是我国南方水果生产上危害最为严重的害虫之一。对橘小实蝇在18,20,25,28,30℃下卵、幼虫、蛹的发育历期及室内条件下成虫羽化、取食、交配、产卵等生物学特性的研究,结果表明,橘小实蝇卵、幼虫、蛹的发育历期随温度的降低而延长,其发育最适温度为25～28℃。在25℃下,卵、幼虫、蛹的平均发育历期分别为1.5,16和13d;在28℃下,卵、幼虫、蛹的平均发育历期分别为1.3,14和12.5d。橘小实蝇的防治措施多使用不育处理技术,引进利用"性诱剂"捕杀柑橘小实蝇技术,达到安全、环保防治的效果。     

对甲基丁香酚无趋性的橘小实蝇遗传性别品系雄虫的筛选

为了弱化橘小实蝇雄性不育技术与性诱灭雄技术间的冲突,本试验尝试从橘小实蝇遗传性别品系中筛选出对ME无趋性的雄虫。研究结果表明,剔除掉每世代对ME有趋性的雄虫后,繁育出的雄虫中对ME无趋性雄虫的比例增加,但只能增加至占总体雄虫的30%左右。室内与田间测试均显示,自F2后,筛选出的雄虫对ME的趋性明显低于对照,交配竞争能力与不经筛选的雄虫相当。     

假眼小绿叶蝉的日飞行活动性及成虫飞行能力的研究

茶树假眼小绿叶蝉（Empoasca vitis Göthe）在早晨和傍晚各有一个飞行活动高峰,早晨的活动高峰时间为6:00~7:00,傍晚的活动高峰时间为16:00~17:00。假眼小绿叶蝉成虫的平均飞行距离、平均飞行时间和平均飞行速度在一天之中不同的时间段下无显著性差异,但雌雄成虫的平均停飞时间在晚上（22:00~23:00）显著增加,在中午（12:00~13:00）雄虫的平均停飞时间显著要长于雌虫。研究结果为假眼小绿叶蝉的生物特征分析和田间防治提供了参考。     

水稻光合日变化与内生节奏的关系

 1986-1990年以水稻原丰早、837等为材料研究了水稻的光合日变化及其与内外因素的关系。水稻的光合日变化呈典型的双峰曲线。光合日变化与气孔开度日变化基本上是同步的。叶面喷水和磷、钾溶液，可减缓光合午睡的程度，但未见午睡消失。延迟见光，短时间的反光周期处理或全光照处理，不改变光合日变化原有的时间节奏。长时间反光周期或全日照处理，则适应形成新的光合日变化规律。说明水稻光合日变化与内生节奏的调节有关。     

Spontaneous internal desynchronization of locomotor activity and body temperature rhythms from plasma melatonin rhythm in rats exposed to constant dim light

Background  

We have recently reported that spontaneous internal desynchronization between the locomotor activity rhythm and the melatonin rhythm may occur in rats (30% of tested animals) when they are maintained in constant dim red light (LL_dim) for 60 days. Previous work has also shown that melatonin plays an important role in the modulation of the circadian rhythms of running wheel activity (R_w) and body temperature (T_b). The aim of the present study was to investigate the effect that desynchronization of the melatonin rhythm may have on the coupling and expression of circadian rhythms in R_w and T_b.     

Adult Behavior of Tirumala limniace (Lepidoptera: Danaidae)

Tirumala limniace Cramer as an ornamental butterfly is utilized in butterfly garden, in this article we study their adult activities include flight, foraging, courtship, mating, and oviposition. We found that males spent 22.1% of its time flying, 14.1% foraging, 63.8% in courtship and mating. And females spent 30.8% of its time flying, 10.1% foraging, 57.1% in courtship and mating, and 2% ovipositing. Adults emerged from pupae when temperatures were above 23.5°C and eclosion took only ∼1 min, typically followed by a small amount of flight on the first day. Flight activity peaked from the ninth to the thirteenth day after eclosion, and there were two daily peak flight times: 10:00–13:00 and 15:00–18:00. The peak of flower-visiting activity was from the eighth to the thirteenth day after eclosion, and there were two daily peak foraging times: 11:00–12:00 and 16:00–17:00. Flight and foraging frequency and time were positively correlated and both were closely related to temperature, with very little flight or foraging below 18°C and an increase at temperatures above 22°C. Courtship and mating took place on the sixth day after eclosion, while oviposition occurred the following day. Oviposition occurred over 8 d, and the shortest time of a single oviposition was 2 s. The average life expectancy of males was 16.5 d, while that of females was 15 d.     

Spontaneous internal desynchronization of locomotor activity and body temperature rhythms from plasma melatonin rhythm in rats exposed to constant dim light

Background  

Daylight saving time is widely adopted. Little is known about its influence on the daily rest-activity cycles. We decided to explore the effects of transition into daylight saving time on the circadian rhythm of activity.     

Determinants of the daily rhythm of blood fluidity

Background  

Numerous processes in the living body exhibit daily rhythmicity. In this study, we characterized a daily rhythm of blood fluidity and identified its determinants.     

Effects of the insecticide triazophos on the ultrastructure of the flight muscle of the brown planthopper Nilaparvata lugens Stål (Hemiptera: Delphacidae)

The brown planthopper (BPH), Nilaparvata lugens (Stål) (Hemiptera: Delphacidae), is a long-distance migratory insect pest in temperate eastern Asia and is a classical resurgent rice pest that is induced by insecticides. Knowledge of the effect of insecticides on the flight capacity of insects is needed to understand their migration, which may help to improve the management of insect pests. Our previous study demonstrated that some insecticides enhance the flight capacity of BPH. However, the effect of insecticides on the flight muscle of BPH is not well understood. Thus, the present study examined the effect of triazophos, a classical insecticide that induces the resurgence of BPH, on the ultrastructure of macropterous females using transmission electron microscopy. The results showed that the diameter of myofibrils one and two days after adult female emergence (DAE) following treatment with 40 ppm triazophos was significantly greater than that of the control, increasing by 31.4 and 21.5%, respectively. In addition, the length of the sarcomeres at two and three DAE was significantly greater than that of the control, increasing by 73.8 and 50.8%, respectively. The percentage of mitochondrial volume in the muscle fibres at one and two DAE was 146.2 and 67.7% greater than that of the control, respectively. These findings show that the mechanisms of triazophos-induced enhancement of the flight capacity of BPH involve changes in the ultrastructure of the flight muscle.     

Summer activity patterns among teenage girls: harmonic shape invariant modeling to estimate circadian cycles

Background

Physical activity as measured by activity counts over short time intervals across a 24 h period are often used to assess circadian variation. We are interested in characterizing circadian patterns in activity among adolescents and examining how these patterns vary by obesity status. New statistical approaches are needed to examine how factors affect different features of the circadian pattern and to make appropriate covariate adjustments when the outcomes are longitudinal count data.

Methods

We develop a statistical model for longitudinal or repeated activity count data that is used to examine differences in the overall activity level, amplitude (defined as the difference between the lowest and highest activity level over a 24 hour period), and phase shift. Using seven days of continuous activity monitoring, we characterize the circadian patterns and compare them between obese and non-obese adolescent girls.

Results

We find a statistically significant phase delay in adolescent girls who were obese compared with their non-obese counterparts. After the appropriate adjustment for measured potential confounders, we did not find differences in mean activity level between the two groups.

Conclusion

New statistical methodology was developed to identify a phase delay in obese compared with non-obese adolescents. This new approach for analyzing longitudinal circadian rhythm count data provides a useful statistical technique to add to the repertoire for those analyzing circadian rhythm data.     

A new model for predicting the flight activity of Lobesia botrana (Lepidoptera: Tortricidae)

The grape vine moth, Lobesia botrana (Denis and Schiffermüller) (Lepidoptera: Tortricidae), attacks vineyards mostly in Southern Europe and Northern Africa. The efficiency of most control methods depends on the treatment of pest populations at their most susceptible stages, therefore the prediction of the moth’s development cycle would help greatly in determining an optimal treatment schedule. One strategy for protecting against this pest is based on the day of maximum flight of males per generation (peak flight), when the mating between males and females and the laying of eggs reaches its maximum. The knowledge of these times would enable us to decide the kind of insecticide and the best time to target it. The time of maximum flight can be predicted by the Touzeau model of accumulated average daily temperature exceeding the development threshold. As shown, the fit of this model on data from the Ribera del Duero region in Spain is not accurate enough. Therefore, we propose an empirical and biologically plausible model based on logistic transformation of daily temperatures, which proves a better fit and permits simple inclusion of additional variables such as relative humidity.     

Time for sex: nycthemeral distribution of human sexual behavior

Background  

Nycthemeral (daily) oscillation has been documented in a variety of physiological and behavioral processes. The present study was carried out to evaluate the existence of a nycthemeral rhythm of human sexual behavior and to identify environmental factors responsible for the rhythmic pattern.