光周期和温度诱导美国白蛾滞育

【目的】探究光周期和温度对美国白蛾滞育的影响,明确诱导美国白蛾滞育的主控因子和幼虫敏感龄期,为深入研究光周期诱导美国白蛾滞育的分子机制和开发新型防治技术奠定基础。【方法】设置4个温度(21、23、25和27℃)和7个光周期(L8∶D16、L10∶D14、L12∶D12、L13∶D11、L14∶D10、L15∶D9和L16∶D8),统计和比较28种不同处理条件下美国白蛾的滞育结果,阐明光周期和温度对美国白蛾滞育和临界光周期的影响; 23℃条件下,在美国白蛾幼虫不同发育阶段分别给予长光照(L16∶D8)和短光照(L10∶D14)交替饲养处理,统计和比较32种不同处理下美国白蛾的滞育结果,明确光周期诱导美国白蛾滞育的敏感龄期。【结果】在21、23、25和27℃条件下,光照时间小于13 h,可导致美国白蛾滞育发生,光照时间达到16 h,美国白蛾个体继续发育而无滞育发生,光照时间在13～16 h之间时,滞育同时受光周期和温度调控,且滞育率随光周期增长或温度升高均呈下降趋势。21、23、25和27℃条件下的临界光周期分别为14 h 58 min∶9 h 02 min(L∶D)、14 h 45 min∶9 h 15 min(L∶D)、14 h35 min∶9 h 25 min(L∶D)和14 h 24 min∶9 h 36 min(L∶D),临界光周期随温度升高逐渐缩短。短光照对美国白蛾滞育诱导具有累积效应,美国白蛾幼虫3龄、4龄和5龄对光周期诱导滞育最为敏感。【结论】美国白蛾属典型的长日照发育-短日照滞育型昆虫,光周期在美国白蛾滞育诱导中发挥主导作用,温度伴随光周期发挥作用,低温和短光照利于滞育发生;临界光周期受温度调控,随温度升高逐渐缩短;美国白蛾对光周期诱导滞育具有累积效应,感受光周期最敏感的阶段为幼虫3～5龄。     

环境温度和光周期对枣镰翅小卷蛾求偶活动及性信息素释放的影响

本文研究了温度和光周期对枣镰翅小卷蛾求偶行为及性信息素释放的影响,结果表明 ,越冬代枣镰翅小卷蛾雌蛾的求偶高峰期为暗期6.0～8.0h。温度越高,雌蛾开始求偶的时间越迟,求偶的持续时间也越短,求偶高峰期比在正常温度下明显推迟。温度为21℃时雌蛾产生的性信息量最高,26℃时略低,而在31℃和16℃时雌蛾性信息素释放量仅为21℃时的1/5～1/4;雌蛾所释放的性信息素中顺、反异构体比例随温度的降低向顺式异构体增加的方向漂移,其变异系数均控制在10%以下。当把第2日龄的雌蛾从14L∶10D光周期转移到连续黑暗下时,雌蛾表现的求偶行为和性信息素产生与14L∶10D下相似,均表现出明显的节律;当转移到连续光照下时,求偶行为变得不活泼和不规则,而产生的性信息素量却等于或高于14 L∶10D光周期下所产生的性信息素量。     

3种饲料对异色瓢虫生长发育的影响

为筛选异色瓢虫的适宜饲料,观察比较了菜缢管蚜、麦蛾卵和人工饲料对异色瓢虫生长发育的影响。结果显示:菜缢管蚜饲养的异色瓢虫发育最快,世代历期为25.3d,产卵前期为11.0d,平均单雌产卵量为929.3粒;麦蛾卵饲养的世代历期为39.5d,产卵前期为18.2d,平均单雌产卵量为391.9粒;人工饲料饲养的世代历期为44.9d,产卵前期为17.2d,平均单雌产卵量为262.3粒。由此表明,菜缢管蚜的饲养效果最好,麦蛾卵和人工饲料虽能满足异色瓢虫世代营养的需求,但发育历期明显延长、产卵量明显下降。因此,在天然食物蚜虫不足时,麦蛾卵和人工饲料可作为补充饲料。     

云南切梢小蠹雌成虫卵巢发育程度的分级研究

[目的]探究卵巢发育与环境温度在云南切梢小蠹生殖和种群繁衍中的作用,进而加深对其种群数量动态和成灾机制的认识。[方法]采用随机抽样法,于2014年12月—2016年1月解剖正在云南松枝梢内取食的云南切梢小蠹雌成虫。[结果]云南切梢小蠹雌成虫卵巢位于第4腹节消化道侧下方,由1对卵巢、2根短侧输卵管、1根中输卵管、受精囊和附腺构成;卵巢包括四根管状的卵巢管,每个卵巢管前端延伸出端丝并集合成悬带,附着于体壁或脂肪体上。根据卵巢发育形态特征的变化,分为透明期(I级)、延伸期(Ⅱ级)、卵黄沉积前期(Ⅲ级)、卵黄沉积期(Ⅳ级)、产卵期(Ⅴ级)共5个等级,卵巢发育过程与蛀梢补充营养密切相关,每一级别可持续1～4月不等; I-Ⅳ级卵巢管长度增长较慢,Ⅴ级增长快速,而卵巢管宽度Ⅱ级和Ⅴ级增加快,卵巢面积呈幂指数级增长。结合环境温度和林间蛀干调查,发现云南切梢小蠹卵巢发育与温度呈正相关,而蛀干产卵与温度负相关。[结论]云南切梢小蠹雌成虫卵巢发育主要集中在Ⅲ～Ⅴ级,且温度影响该蠹虫的蛀梢和蛀干产卵,研究可为云南切梢小蠹产卵期的预测预报提供理论依据。     

黄野螟的羽化和生殖行为节律

黄野螟Heortia vitessoides Moore是近年来大面积爆发的严重危害土沉香Aquilaria sinensis(Lour.)Gilg的食叶害虫,为寻找其羽化和生殖行为发生规律,为生态防控提供技术参考,在温度(25±1)℃,光周期L:D=14:10,相对湿度RH=75%~80%的条件下,观察了黄野螟成虫的羽化和生殖行为。结果表明:黄野螟的羽化率为83.20%,羽化期为10 d左右,日羽化高峰在20∶00~22∶00,雌雄性比为1.12∶1,且雄蛾先于雌蛾羽化。成虫在羽化后2 d达到性成熟,2日龄雌蛾开始求偶,3~4日龄雌蛾求偶最为强烈,雌蛾的求偶行为多发生在20∶00~21∶00,成虫光期未见交尾行为,成虫日龄影响交尾行为,4日龄成虫交尾率最高。卵多产于叶片背面,孵化率超过90%。交尾雌虫和雄虫的平均寿命为6.32 d和5.75 d,未交尾雌虫和雄虫的平均寿命为8.83 d和8.24 d,说明交尾缩短雌雄成虫寿命。     

杜鹃三节叶蜂羽化与生殖行为节律观察

野外采集杜鹃三节叶蜂Arge similis 3龄及以上老熟幼虫或茧在室温(25±1)℃、光周期L∶D=14∶10(光期6∶00—20∶00,暗期20∶00—6∶00)、空气相对湿度RH=75%±10%的实验室饲养,观察成虫羽化、求偶、交尾等生殖节律。结果表明:杜鹃三节叶蜂结茧后10 d即可羽化,主要集中在蛹期12~16 d的光期,13 d为羽化高峰,光期3~7 h(9∶00—13∶00)为羽化高峰期;求偶行为主要发生在光期7. 5~9 h(13∶30—15∶00),高峰期出现在光期8. 5 h(14∶30),雌虫求偶率和求偶次数随着日龄增大而降低;成虫交尾主要集中在前3日龄,交尾持续时间随日龄增加而下降,交尾后雌虫的平均产卵量为25粒。     

河北省长针线虫新纪录种松长针线虫Longidorus pinus Xu,Ye,Wang & Zhao的形态与分子鉴定

2018年,在河北省保定市园林植物紫荆(Cercis chinensis)根围分离到一种长针线虫。经形态学观察和28S rDNA D2D3区序列分析,将其鉴定为松长针线虫(Longidorus pinus Xu, Ye, Wang&Zhao)。其雌虫主要形态特征为:雌虫体长3 048～3 464μm,唇区明显缢缩,宽9.5～10.5μm,侧器囊袋状,齿尖针长66.0～69.5μm,导环距体前端27.5～30.0μm,尾长31～33μm,短圆锥形,尾长与肛门处体宽比值=1.5～1.6。松长针线虫河北种群28S rDNA D2D3区与GenBank数据库的山西种群进行序列比对,相似性为99.2%～99.9%。松长针线虫是河北省长针线虫新纪录种。紫荆是松长针线虫的新寄主。     

光周期和温度对美凤蝶滞育诱导的影响

对光周期和温度对美凤蝶峨眉种群滞育诱导的影响进行了研究,结果表明:光周期对美凤蝶滞育的诱导作用与温度有关,在20℃的恒温条件下,光照在12～13 h范围内,随着光照时间的缩短,滞育个体增加,在光照时间短于12.5 h后达到100%;在25℃时,光照时间在11～13.5 h范围内,随光照时间的缩短,滞育率增加,但没有出现全部个体滞育的情况,最高滞育率为94.5%;在30℃时,在实验光周期范围内没有出现滞育个体.温度对滞育的影响受光周期的影响,在相同光照条件下,在一定温度范围内,随着温度的上升,滞育率下降,当温度上升幅度达到30℃,无论长短光照条件下均不出现滞育个体.只有在短光照条件下,低温才有利于滞育,而长光照和高温则有利于个体的发育而抑制滞育产生.短光照对滞育的诱导作用具有累积效应.在20℃恒温条件下,美凤蝶的临界光周期为LD 13 h 11 min:10 h 49 min;而在25℃恒温条件下,美凤蝶的临界光周期为LD 12 h 49 min:11 h 11 min.随着温度的升高,临界光照长度缩短.美凤蝶对光周期的敏感期为5龄幼虫.     

青斑蝶雌成虫内生殖器官形态与发育

[目的]青斑蝶是重要的观赏性昆虫,准确掌握和了解其内生殖器官结构和发育状态,能够为其人工培育和利用提供理论依据。[方法]通过对1 12日龄青斑蝶雌成虫内生殖系统解剖,观察内生殖器官结构组成,并测定内生殖器官特征参数,同时根据内生殖器官各组成部分特征对雌性卵巢发育进行分级,从而系统了解青斑蝶雌成虫内生殖器官形态与发育。[结果]1)雌性青斑蝶的内生殖器官由1对卵巢、1对侧输卵管、1根中输卵管、交配囊腺和受精囊组成;2)内生殖器官发育显著受到日龄影响,卵巢管长度随着日龄增长而显著生长,至10日龄最长,卵巢小管和侧输卵管直径随日龄增长而缓慢增大;3)随着日龄的增长,卵巢中成熟卵的数量先增大后减小,未成熟卵数量始终缓慢增加;4)根据卵巢的发育特征,将卵巢发育分为乳白透明期、卵黄沉积期、成熟待产期、产卵盛期、产卵末期。[结论]雌性青斑蝶内生殖器官结构组成与其它蝴蝶类似,其发育均显著受到日龄影响,卵子发育随日龄增长而逐渐成熟。雌性青斑蝶卵巢分级将为人为调控雌蝶产卵量提供理论指导。     

四种赤眼蜂对槐尺蠖卵的寄生能力及适应性

为筛选有效防治槐尺蠖Chiasmia cinerearia的优势赤眼蜂蜂种,在温度(25±1)℃、相对湿度(60±5)%、光周期14 L∶10 D的恒温培养条件下,比较4种赤眼蜂对槐尺蠖卵的寄生能力和发育适合度。结果表明：4种赤眼蜂均可寄生槐尺蠖卵,但寄生数量有差异。松毛虫赤眼蜂Trichogramma dendrolimi单雌平均寄生57.9粒卵,与玉米螟赤眼T.ostriniae单雌平均寄生44.7粒无显著差异,但显著高于螟黄赤眼蜂T.chilonis和广赤眼蜂T.evanescens。4种赤眼蜂寄生槐尺蠖卵后,均能顺利完成发育,羽化率均高于97.0%,发育历期为9.0～9.9 d,子代雌蜂率均高于65.0%,单卵子蜂数为1.0～2.0头。松毛虫赤眼蜂每雌子代总蜂数平均为84.9头,且显著高于其他3种赤眼蜂。松毛虫赤眼蜂的寄生能力最强,可作为防治槐尺蠖的候选赤眼蜂用于进一步的田间防治试验。     

Wirkungen der Fotoperiode und Temperatur auf die Entwicklungsstadien von Acrotylus insubricus Scop. (Orthopt., Acrididae)

Effect of photoperiod and temperature on the developmental stages of Acrotylus insubricus Scop. (Orth., Acrididae) The effect of different temperatures and photoperiods on the developmental stages ofAcrotylus insubricus Scop. was studied. The species has no embryonic or nymphal diapause. The relatively low temperature of the winter months prolonges the incubation period as well as the nymphal development. By rising temperature both eggs and nymphs began to continue their development. The shortest nymphal duration at 27 °C (63.9 days) was obtained when rearing nymphs at long photoperiod (16L:8D), while the longest duration (92 days), was recorded at short photoperiod (8L:16D). In intermediate photoperiod (12L:12D), the nymphal duration was 82.8 days, between the long and the short photoperiods. At 37 °C, the nymphal durations were shorter than at 27 °C and still the shortest at a long day (4310 days) than the two other conditions. The total nymphal mortality was higher at short day-length than that at the other photoperiods tested. The incubation period as well as the percentage of hatching were not affected by the different photoperiodic regimes while the low temperature prolonges the incubation period and nymphal development. The higher temperature (37 °C) tended to mask or abolish the effect of the photoperiod while the moderate temperature (27 °C) clarified this effect when the two factors were combined together.     

Über die Wirkung der Photoperiode auf den Schlüpfrhythmus der Falter vonSpodoptera littoralis Boisd. (Lep., Noctuidae)

Effect of photoperiod on emergence rhythm of adult Spodoptera littoralis Bolsd. (Lep., Noctuidae) Adult emergence ofSpodoptera littoralis Boisd. from pupae, reared since the egg stage at different photoperiodic conditions was studied. The photoperiods tested were: 8 hours light and 16 hours darkness (8L:16D), 10L:14D, 12L:12D, 16L:8D together with continuous light (24L:0D) and complete darkness (0L:24D), In the shortest day-length (8L:16D) all adults emerged at night, while in the longest one (16L:8D) 40%) only emerged during the dark period of the day. In the intermediate photoperiods, the percentage of the light-emerging moths increased with the prolongation of the photophase, thus at the photoperiods of 10L:14D, 12L:12D and 14L:10D such percentages were 9, 13 and 28 respectively. In cases where insects were reared in continuous light (24L:0D) or complete darkness (0L:24D), emergence took place at random and the rhythmicity disappeared. By transferring newly formed pupae, reared in complete darkness, to photoperiod of 12L:12D, adults emerged mainly during the dark phase (90%). On the other hand, when pupae reared in 12L:12D were transferred to complete darkness emergence took place at random (arrhythmic emergence). This indicates that the pupal stage is the sensitive one to phase regulation and not the larval stage.     

Spring growth of Douglas-fir seedlings from two bud development regimes

The effect of two bud development treatments on post-dormancy shoot growth was investigated with 1-year-old container-grown Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco) seedlings. A difference in the date of budset and number of overwintering primordia was obtained by applying 8-hour or 17-hour photoperiods in growth rooms during summer months. Seedlings were then chilled for 14 weeks at 4 °C and finally held 2 months at 22 °C under either an 8-hour or 16-hour photoperiod. The new shoot growth of seedlings with early budset had greater length, stem unit numbers, average stem unit length, and dry weight. Stem unit number of the post-dormancy seedlings was unaffected by photoperiod during flushing. Significant free growth occurred only in late budset seedlings and accounted for 40% and 46% of the fixed growth under 16-hour and 8-hour flushing photoperiods, respectively.     

光周期和低温处理对泡桐叶片抗性影响研究

对毛泡桐1年生实生苗进行不同光周期和低温处理。结果表明:在相同光周期条件下,随着温度的降低SOD与CAT活性逐渐降低;MDA与脯氨酸含量逐渐上升,D16L8和D14L10光周期条件下较D8L16和D12L12条件下提前进入休眠。     

Bud dormancy in beech (Fagus sylvatica L.). Effect of chilling and photoperiod on dormancy release of beech seedlings

Two-year-old Fagus sylvatica L. seedlings were subjected to natural winter chilling or were overwintered in a heated greenhouse. Plants were then grown in controlled environment chambers with photoperiods of 9 or 13 h. Renewal of bud growth was found to be mainly determined by winter chilling. There was a slight interaction between chilling and photoperiod. Sprouting of apical buds took two to three times as long in unchilled plants as in chilled plants. Shoot elongation was influenced by chilling and was also greater in the 13-h photoperiod than in the 9-h photoperiod, but this may have been due at least in part to the higher irradiance. Chilling resulted in rapid dormancy loss and changed the growth pattern from basitonal to acrotonal.     

桉树杂交种生长及抗风性状的遗传分析和选择

为了筛选出优良家系及单株,为桉树良种改良提供优质的遗传材料,对27月生30个桉树杂种家系试验林的生长和抗风能力进行分析和遗传评估.结果表明:试验林的树高(H)、胸径(D)、材积(V)、抗风指数(WR)在家系水平上、家系×重复交互作用水平上均存在极显著的差异(P＜0.01),在家系水平上4个性状均受到较高程度的遗传控制,单株水平上H、D、V3个性状受到较高强度的遗传控制,而WR受到较弱程度的遗传控制.遗传相关分析表明H、D、V、WR4个性状两两之间都呈极显著正相关(P＜0.01),其中,在生长性状中,D与V之间的相关关系最为密切;在抗风能力方面,WR与D之间的相关关系最为密切.通过构建性状选择指数方程,按照选择标准选出8个优良家系,39个优良单株,入选率分别为26.67％、5.65％.其中优良家系的遗传增益在H、D、V和WR上分别达到了8.24％、9.99％、25.24％和3.76％,优良单株的遗传增益在H、D、V和WR上分别为22.55％、13.45％、105.49％和1.90％.     

小悍蟋若虫发育的光周期反应模式

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