苜蓿籽蜂越冬虫态对温度的敏感性

本研究将当年收获的苜蓿（Medicago sativa）种子储存于4个温度条件下,采用定期剖种的方法,调查苜蓿籽蜂（Bruchophagus roddi）的越冬虫态及其存活情况。结果表明,苜蓿籽蜂主要以3龄幼虫在苜蓿种子内滞育越冬。10月从田间将苜蓿种子收回,储存温度在18.0 ℃、平均湿度为27.2%（10―12月）时,越冬幼虫于当年12月下旬开始化蛹;储存温度在9.9 ℃,平均湿度为40.1%（10月―次年2月）时,越冬幼虫于次年2月下旬开始化蛹。不同温度和不同时间梯度处理苜蓿种子结果表明,在50 ℃、-30 ℃条件下处理1 d,籽蜂幼虫的死亡率均达100%,苜蓿种子的发芽率分别为93.33%和88.33%。     

桑螟越冬幼虫滞育解除和发育历期的初步研究

研究了桑螟越冬幼虫滞育解除作用,结果表明:加温处理是桑螟越冬幼虫滞育解除的主导因子,30℃时经过4d即可化蛹,平均化蛹前期9.7d,平均蛹历期7.6d,平均蛾历期3.6d;20℃时最短10d化蛹,平均化蛹前期23.5d,平均蛹历期17.7d,平均蛾历期5.4d。30℃对越冬桑螟化蛹前期的发育比20℃有利,而20℃时桑螟蛹期的成活更高,有利于延长蛹期光照总时长,提高羽化率。低温刺激、不同光周期对越冬桑螟幼虫滞育解除无明显的促进作用。     

不同饲养基质对豆天蛾越冬影响的研究

研究豆天蛾的越冬条件,以便为饲养繁殖豆天蛾提供科学依据。以纯土、蘑菇料土、锯末土和纯锯末为豆天蛾越冬的饲养基质,通过用4种饲养基对豆天蛾的室内、室外处理发现,室内处理的豆天蛾化蛹率为纯锯末>锯末土>蘑菇料土>纯土,死亡率为纯锯末>纯土>蘑菇料土>锯末土;室外处理的豆天蛾化蛹率为纯锯末>锯末土>蘑菇料土>纯土,死亡率为纯土>蘑菇料土>纯锯末>锯末土。研究结果表明,饲养基质中有机质的含量影响豆天蛾的化蛹率和死亡率,豆天蛾趋向于含有有机质较多的饲养基质中越冬。     

甘肃省5种昆虫病原线虫对草地贪夜蛾的致病力测定

探讨甘肃省昆虫病原线虫对草地贪夜蛾(Spodoptera frugiperda)的防治效果。通过室内生物测定研究了甘肃省5种10个昆虫病原线虫品系对草地贪夜蛾2龄幼虫的致病力,并用筛选出的高效品系对预蛹和蛹进行致病力测定。结果表明,夜蛾斯氏线虫(Steinernema feltiae) 0663PG和卡森斯氏线虫(Steinernema krussei) 0657L对草地贪夜蛾2龄幼虫有较高的致病力。在线虫和2龄幼虫数量比为160∶1时,夜蛾斯氏线虫0663PG和卡森斯氏线虫0657L侵染72 h后,草地贪夜蛾死亡率分别达到100%和80%。草地贪夜蛾预蛹在夜蛾斯氏线虫0663PG的处理下2 d后均可成功化蛹,处理15 d后在数量比为3 200∶1时,蛹的羽化率为96.67%。数量比为12 800∶1时,夜蛾斯氏线虫0663PG侵染草地贪夜蛾蛹13 d后,蛹的羽化率为93.33%,夜蛾斯氏线虫0663PG对草地贪夜蛾预蛹和蛹的致死率均低于10%。综上可知,夜蛾斯氏线虫0663PG线虫品系对草地贪夜蛾幼虫具有较好的防治效果。草地贪夜蛾预蛹和蛹对昆虫病原线虫不敏感,线虫侵染后对蛹的羽化率和羽化时间没有显著影响(P 0.05)。     

甘肃省5种昆虫病原线虫对草地贪夜蛾的致病力测定

探讨甘肃省昆虫病原线虫对草地贪夜蛾(Spodoptera frugiperda)的防治效果.通过室内生物测定研究了甘肃省5种10个昆虫病原线虫品系对草地贪夜蛾2龄幼虫的致病力,并用筛选出的高效品系对预蛹和蛹进行致病力测定.结果表明,夜蛾斯氏线虫(Steinernema feltiae)?0663PG和卡森斯氏线虫(Steinernema krussei)?0657L对草地贪夜蛾2龄幼虫有较高的致病力.在线虫和2龄幼虫数量比为160:1时,夜蛾斯氏线虫0663PG和卡森斯氏线虫0657L侵染72?h后,草地贪夜蛾死亡率分别达到100％和80％.草地贪夜蛾预蛹在夜蛾斯氏线虫0663PG的处理下2?d后均可成功化蛹,处理15?d后在数量比为3200:1时,蛹的羽化率为96.67％.数量比为12800:1时,夜蛾斯氏线虫0663PG侵染草地贪夜蛾蛹13?d后,蛹的羽化率为93.33％,夜蛾斯氏线虫0663PG对草地贪夜蛾预蛹和蛹的致死率均低于10％.综上可知,夜蛾斯氏线虫0663PG线虫品系对草地贪夜蛾幼虫具有较好的防治效果.草地贪夜蛾预蛹和蛹对昆虫病原线虫不敏感,线虫侵染后对蛹的羽化率和羽化时间没有显著影响(P?>?0.05).     

人工低温冷藏处理解除一化性柞蚕越年蛹滞育试验初报

采用人工低温冷藏处理一化性柞蚕越年蛹 ,具有解除其滞育的效果。在温度为 0℃下冷藏处理一化性柞蚕越年蛹 8d、6 d、4d和在温度为 - 1 8℃下冷藏处理 4d,其解除一化性柞蚕越年蛹滞育的效果与出蛾集中程度、制种成绩等均优于现行的感光处理解除滞育的方法。出蛾的实际时间较感光处理解除滞育法推迟了 3 d以上     

余甘子蛀干害虫——桔斑簇天牛生物学特性研究

通过野外调查和室内饲养对发生在云南保山余甘子Phyllanthus emblica Linn.植株上的桔斑簇天牛Aristobia approximator（Thomson）形态特征和生物学特性进行研究。结果表明，桔斑簇天牛1年发生1代，以卵和1~3龄幼虫在产卵槽底部和蛀食坑道内越冬。越冬期大龄幼虫于翌年3月下旬化蛹，低龄幼虫于5月下旬化蛹，蛹平均历期65~78d。6月上旬至10月上旬为成虫羽化期，6月下旬至8月中旬为羽化高峰期，成虫平均寿命为38~47d。7月上旬至10月上旬为产卵期，树皮厚度为3~5mm之间的产卵量最多，产卵率为96.03%。7月中旬至11月下旬为卵孵化期，卵孵化率为91.80%，卵的平均历期18~25d。10月中旬卵和幼虫进入越冬，10月中旬至11月下旬平均气温在10~15℃时越冬卵孵化率下降为57.30%。越冬期幼虫处于持续蛀食发育状态，幼虫平均历期为225~240d，幼虫大致分为6龄，4~5龄幼虫取食量最大，平均单日蛀道容积为28.26cm3。     

短期低温冷藏对柑橘大实蝇蛹发育的延迟效应

柑橘大实蝇Bactrocera minax（Enderlein）为我国柑橘类的重要害虫，其人工饲养技术尚未突破，虫源主要从野外收集并于室内保蛹。而短期低温冷藏对其蛹发育的延迟效应尚不明确。作者研究了柑橘大实蝇0级蛹在10℃下短期冷藏后，对1级蛹、2级蛹、3级蛹和4级蛹发育的延迟效应。结果表明：10℃冷藏处理0级蛹0d、29 d、35 d、40 d、45 d后，1级蛹、2级蛹、3级蛹和4级蛹，蛹级高峰延迟天数分别符合线性关系y = 0.5195x -1.6813（R2 = 0.9104）、 y = 0.4605x - 1.7231（R2 = 0.8668）、 y = 0.6888x -1.9274（R2 = 0.9058）、 y = 0.6773x - 3.9843（R2 = 0.6841）。成虫羽化高峰期延迟天数符合线性回归方程：y = 0.4135x – 2.1222（R2 = 0.7616）。冷藏40 d和45d时， 羽化率显著下降。柑橘大实蝇0级蛹在10℃冷藏35d时，1级、2级、3级和4级蛹高峰分别可延迟15d、15d、24d和15d。本文结果可为柑橘大实蝇蛹的保存和成虫预测提供依据。     

黑绒金龟甲的发生规律研究

采用田间调查及室内饲养观察相结合的方法,研究了黑绒金龟甲(Serica orientalis)在兰州市的生活史、降水量对其田间消长动态的影响以及室内温度对其生长发育、卵孵化的影响。结果表明:25℃条件下,黑绒金龟甲的卵期6~9 d,幼虫3龄,幼虫期为53~86 d,蛹期9~16 d,成虫期长达9个多月,即280 d;黑绒金龟甲在兰州一年发生1代,4月下旬入蛰成虫开始出土,5月中旬~6月下旬成虫交配产卵;5月下旬~7月上旬为幼虫危害时期,7月中旬老熟幼虫开始转入地下化蛹,8月中旬蛹开始羽化,成虫当年不出土,在地下越冬,翌年4月下旬出蛰,黑绒金龟甲卵在18℃以下不能孵化,22~30℃时卵的历期随温度的升高逐渐缩短,32~35℃卵的历期则随温度的升高逐渐延长;其中,30℃时卵的孵化天数最短,为6.6 d;25℃时卵的孵化率最高,为95.00%,35℃时孵化率最低为21.25%。黑绒金龟甲的发生量与降水量有关,在每一个降水高峰期后,黑绒金龟甲的出土量明显增加。     

不同储藏方式对鸡蛋品质的影响

 为探讨夏季常温保存和低温冷藏两种储藏方式对鸡蛋品质的影响,选择540个鸡蛋随机分为9组,1组当天测定蛋品质,3组置于28.31 ℃、湿度为68.13%的室温下保存,5组置于4~8 ℃的冷藏室保存,分别于第7、14、21、42和56 d测定蛋品质。结果表明,常温储藏的鸡蛋随着存放时间延长,鸡蛋品质不断下降,储藏21 d后,蛋重降低5.30%（P<0.05）,蛋壳厚度变薄（P<0.05）;哈氏单位随着储藏时间的延长迅速下降,第0 d比第21 d的哈氏单位值高59.18%（P<0.05）;蛋黄比率随储藏时间的延长有不断变大的趋势,第0 d的蛋黄比率比第21 d低15.58%（P<0.05）。低温冷藏的鸡蛋储藏到21 d时,仅哈氏单位比第0 d低6.78%（P<0.05）;冷藏到56 d时,蛋重和哈氏单位比第0 d分别降低5.63%和15.07%（P<0.05）,蛋黄比率提高了5.21%（P<0.05）。试验表明,鸡蛋在室温下的新鲜度适宜保存期不应超过21 d;低温冷藏时可以保存到56 d。     

26种昆虫体内的1-脱氧野尻霉素含量测定

为发掘新的富含1-脱氧野尻霉素(DNJ)的昆虫资源,共测定了26种昆虫体内的DNJ含量。除家蚕(Bombyxmori)之外,野桑蚕(Bombyx mandarina)、桑蟥(Rondotia menciana)、桑尺蠖(Phthonandria atrineata)、桑螟(Diaphaniapyloalis)等4种仅取食桑叶的单食性或寡食性昆虫也富含DNJ,其中桑蟥和桑尺蠖幼虫中的DNJ质量分数分别为1.0648%±0.1134%、0.5138%±0.0083%,高于家蚕幼虫中的DNJ含量(0.4238%±0.0108%),并且桑尺蠖春季越冬代幼虫及其室内桑叶饲育的第1代幼虫和蛹、成虫均含有DNJ,具有开发利用价值。从桑园采集的兼性食桑昆虫中,人纹污灯蛾(Spilarectia subcarnea)、美国白蛾(Hlyphantria cunea)、大造桥虫(Ascotissele naria)、黄斑星天牛(Anoplophora nobilis)等4种昆虫的幼虫中含有微量DNJ,而褶翅尺蠖(Zamacra excauvata)、枣尺蠖(Sucra jujuba)、桑毛虫(Euproctis similis xanthocampa)幼虫和桑天牛(Apriona ger-mari)成虫中不含DNJ。豆天蛾幼虫(Clanis bilineata)等13种非食桑昆虫体内均不含DNJ。研究结果也提示取食桑叶的昆虫对DNJ的富集能力存在很大差异。     

Studies on Rhinoestrus purpureus (Diptera: Oestridae) larvae infesting donkeys (Equus asinus) in Egypt. III. Pupal duration under controlled conditions.

The pupal duration of Rhinoestrus purpureus was studied under variable degrees of temperature and relative humidity (RH). It was found that pupal duration was affected by temperature but not by RH. An increase in the temperature above 22 degrees C decreased the pupal duration: 26-27 days at 22 degrees C, 16-24 days at 27 degrees C, 13-15 days at 32 degrees C. At 37 degrees C, the pupated larvae failed to pupate and died. The deformity ratio of emerged flies was 25-30% at 22-32 degrees C, but it was directly proportional to RH at a constant temperature of 32 degrees C: 26.1% at 75% RH, 16.7% at 50% RH, 6.7% at 30% RH. It was concluded that the optimum temperature and RH for obtaining normal active flies were 32 degrees C and 30%, respectively.     

Development and survival of free-living stages of equine strongyles under laboratory conditions

In a series of laboratory studies the optimum conditions for the development and survival of the free-living stages of strongyle parasites occurring in horses in tropical north Queensland were determined. No differences in behaviour were noted between the strongyle species. Development to the infective stage occurred only between 10 and 35 degrees C. The rate was affected by temperature, taking 15-24 days and 3 days, respectively, at the lowest and highest temperatures for the developing stages to reach the infective third stage. Yields of infective larvae were very low outside the range 20-33 degrees C, and were highest at 28 degrees C. Survival of infective larvae was good between 20 and 33 degrees C, and large numbers were recovered after 3 months in faeces incubated at 20-28 degrees C. At 33 and 37 degrees C larval survival was affected by the moisture content of the faeces, with infective larvae surviving better in dry than in moist faeces; even a residual moisture level of 40% significantly reduced the number of larvae recovered from faeces incubated at 37 degrees C for 1 month. Moisture also affected larval development, especially at the higher temperatures of 25-39 degrees C. When faecal moisture content fell to less than or equal to 20% by 3 days, larvae which had not yet reached the infective stage were still pre-infective at 7 days, while all larvae in faeces with adequate moisture had reached the infective third stage. It was not possible to determine the critical faecal moisture level below which larval development ceased, however, 28 degrees C (range 25-33 degrees C) was found to be the optimum temperature. Larval development was very rapid and yields of infective larvae highest at this temperature.     

The role of temperature and light on inhibition of development of Cooperia oncophora.

Infective Cooperia oncophora larvae were temperature and light conditioned by holding them at various temperatures and daily light intensities for up to 56 days prior to administration to parasite-free calves via stomach tube. The calves were killed either on day 20 or day 21 postinfection. A marked (up to 80.5%) inhibition of development occurred in larvae held at 4 degrees C while little or no inhibition occurred in larvae held at room temperature or in fresh larvae. Marked inhibition also occurred in larvae held at 15 degrees C for 56 days while a low rate of inhibition occurred in larvae held at 17 degrees C for 42 days. Low incidence of inhibition was recorded in two of four calves given larvae held at ambient temperatures of mid-summer while appreciable inhibition of development of larvae occurred in two calves permitted to graze during the second and third week of September in 1975. Temperature conditioning of C. oncophora eggs for 27 days did not result in inhibition of development of infective larvae subsequently cultured from the eggs. Photoperiod or the presence of light did not have any appreciable effect on the development of inhibition of C. oncophora under the conditions of these investigations.     

饲料蛋白质含量对家蚕生长发育和繁殖的影响

本试验用脱脂大豆粉和纤维素粉含量不同的8种人工饲料处理5龄雌蚕。结果用含蛋白质5.62%的饲料,蚕仅存活6.12天;含9.12％的,结茧少且不能化蛹,高于12.63%时能正常结茧化蛹。随着饲料蛋白质含量从9.12％增至37.18％,五龄经过从10.5缩短至7天,熟蚕体重从2.35克增至3.93克,干物消化量从0.40克升至0.86克,消化率从14.49％升至33.08％。但全龄干物食下量和排粪量则以取食蛋白质含量为12.63％的最高,而以取食37.18%的最低。蛹重和卵量也随五龄饲料蛋白含量升高而增加。     

Recovery of nematode eggs and larvae in deer: evaluation of fecal preservation methods

Fresh fecal specimens from deer were examined for nematode eggs (primarily Haemonchus and Ostertagia), using a flotation technique (sugar, sp gr = 1.27), and then were reexamined for up to 200 days after storage in 2.5, 5, or 10% formalin, absolute methyl alcohol, or 70% ethyl alcohol at room temperature (20 C) or after storage without preservative at 4, 0, or -20 C. For long-term storage, 10% formalin was the best fixative for recovery of eggs (compared with the rate of recovery of eggs from fresh feces). Approximately 50% of the strongyle eggs were detected in feces stored in formalin for 200 days. However, between days 3 and 10 of storage, the recovery rate was low (less than 50%), presumably due to ion binding. Alcohols were unsuitable for preservation, and storage at 0 or -20 C resulted in an egg recovery rate of less than 50%. Storage at 4 C for 50 days resulted in approximately 90% recovery of nematode eggs. Number of Parelaphostrongylus tenuis larvae recovered from fecal specimens stored in 10% formalin for 24 days was greater than that recovered from fresh fecal specimens.     

Effect of condensed tannins extracted from four forages on the viability of the larvae of deer lungworms and gastrointestinal nematodes

The inhibitory activity of condensed tannins extracted from four forage legume plants were evaluated by using a larval migration inhibition assay. The first (L1) and third (L3) stages of deer lungworm (Dictyocaulus viviparus), and the third stage (L3) of deer gastrointestinal nematodes were incubated with tannins extracted from Lotus pedunculatus, Lotus corniculatus, sulla (Hedysarum coronarium) and sainfoin (Onobrychus viciifolia). The tannins extracted from all the forages had inhibitory activity as measured by their ability to paralyse the larvae and inhibit them from passing through sieves. At the highest concentration used (1200 microg/ml) the tannins extracted from sainfoin had the highest activity against ensheathed L1 lungworm larvae (58 per cent), followed by L. pedunculatus (45 per cent), sulla (42 per cent) and L. comiculatus (35 per cent) when the larvae were incubated at 37 degrees C. The same trend, but with lower activities, was observed when the larvae were incubated at 22 degrees C. Anthelmintic activity against L3 lungworm larvae was evaluated by measuring the death rate of ensheathed L3 larvae after incubation with condensed tannins for two, 24 and 48 hours at room temperature (22 degrees C). The death rate was significantly higher (P<0.001) after 48 hours incubation than after two hours or 24 hours, and significantly higher (P<0.001) after 24 hours than after two hours incubation. Condensed tannins from sainfoin had the highest inhibitory activity followed by L. pedunculatus, sulla and L. comiculatus. The tannins from sainfoin also had the highest activity against L3 larvae of gastrointestinal nematodes, followed by L. pedunculatus, sulla and L. comiculatus. Exsheathed larvae of gastrointestinal nematodes were significantly more susceptible to the action of the tannins than ensheathed larvae.     

粗狭肋鳃金龟的生物学特性及防治

粗狭肋鳃金龟（Holotrichia scrobiculata Brenske）是蓝莓主要害虫，以幼虫在地下啃食根系为害。为掌握该虫在麻江的发生特点，探讨有效的综合防控措施，采用定期定点调查及室内饲养相结合的方法，对该虫的生物学特性进行了系统研究。结果表明：粗狭肋鳃金龟在贵州省黔东南州麻江县1年发生1代，以蛹越冬；翌年3月下旬至6月下旬成虫羽化出土，5月上旬开始产卵，5月下旬幼虫孵化，12月上旬老熟幼虫开始作蛹室化蛹并在土中越冬。成虫于每晚6点至10点集中出土并转移至壳斗科植物上进行取食或生殖活动，出土高峰期为4月下旬至6月上旬，寿命22.50-24.40 d；晚上20:00-21:00为成虫交配高峰期，交配后4-7天开始产卵，卵期10-20 d，产卵高峰期为6月，单雌产卵量30-50粒，散产；7月为幼虫孵化盛期，幼虫共3龄，历期219-252 d。此外，提出了黑光灯诱杀、人工采虫、冬季深耕翻土等有效的防治方法。