Insect hormones: olive oil is not an inert vehicle for hormone injection into locusts

Like other fatty oils from plants, olive and peanut oils, the most commonly used vehicles for the injection of juvenile hormone and its analogs, contain substances that show effects similar to those of this hormone. A dose of olive oil smaller than that used to dissolve a single injection of juvenile hormone will cause nuclear enlargement in the cells of the prothoracic gland of the desert locus and advance the succeeding molt.     

Reproductive effort, molting latitude, and feather color in a migratory songbird

Toward the end of the breeding season, migratory songbirds face crucial tradeoffs between the timing of reproduction, molt, and migration. Using stable hydrogen isotopes, we show that male American redstarts investing in high levels of reproduction late in the season adopt a unique strategy of combining molt and migration. Tail feathers molted during migration also reflect less orange-red light, indicating reduced carotenoid concentration. Thus, we show how reproduction in a migratory animal can influence both life history strategies (location of molt) and social signals (feather color) during subsequent periods of the annual cycle.     

Lysosomal and free acid phosphatase in salivary glands of chironomus tentans

In cells of salivary glands of last-instar larvae of Chironomus tentans, acid phosphatase activity is bound to (probable) lysosomes and a few other cell organelles. At the end of the pupal molt the salivary gland breaks down. While acid phosphatase in areas of nondegenerated cells is still restricted to the structures mentioned, in degenerated areas the enzyme is freely distributed in the cytoplasm.     

Endogenous reproductive rhythms in a tropical bird

Like other tropical birds, African stonechats breeding at the equator reproduce once a year during the main rainy season and subsequently carry out a complete molt. These two activities are controlled by endogenous circannual mechanisms: in stonechats held in constant conditions of photoperiod and temperature, a rhythm of gonadal size and molt persisted for up to 7.5 years, which would be a lifetime for free-living conspecifics. The fact that the period of these rhythms deviated from 12 months demonstrates their true endogenous nature. The results represent the longest circannual reproductive rhythm yet documented and suggest that circannual mechanisms may be of particular importance for reproductive timing in tropical organisms.     

Feather Replacement in Birds

During natural molt in many birds, feathers of the old generation are passively pushed out of the follicles attached to the tips of the sheaths of incoming feathers.     

黔西南园林植物草履蚧生物学特性观察及药效试验

为了对黔西南地区危害园林植物的草履蚧(Drosicha corpulenta Kuwana)的防治提供参考,对草履蚧进行了生物学特性观察和药剂防治试验.该虫在黔西南1年发生1代,以卵在树干周围的土层(10 cm左右)、土缝、石缝、草堆中越冬.1月中旬卵开始孵化,3月中旬至4月上旬蜕皮,4月下旬开始出现成虫,5月中旬交配,5月下旬至8月下旬产卵.雄若虫4月上旬第2次蜕皮后化蛹,雌若虫第2次蜕皮后则继续取食,4月下旬至5月上旬第3次蜕皮成成虫.40%速扑杀乳油1 000倍液、40%氧化乐果乳油1 000倍液对草履蚧具有良好的防效,药后7 d的防效均达90%以上.     

中国龙虾人工养殖饵料的初步研究

本文研究了贻贝、牡蛎、杂虾、杂蟹、杂鱼和配合饲料６种饵料对中国龙虾的饲养效果。结果表明：饵料对中国龙虾的蜕壳率、蜕壳后体重增长率、生长率和饵料转换效率有显著的影响,而对中国龙虾蜕壳后体长增长率和存活率影响并不明显。各种试验饵料中翡翠贻贝是饲养中国龙虾的最好饵料,其次是牡蛎、杂虾、杂蟹、杂鱼只能作为辅助性饵料,配合饲料的某些成分及其适品性、诱食性尚需改善和提高。     

中国龙虾人工养殖饵料的初步研究

本文研究了贻贝、牡蛎、杂虾、杂蟹、杂鱼和配合饲料６种饵料对中国龙虾的饲养效果。结果表明：饵料对中国龙虾的蜕壳率、蜕壳后体重增长率、生长率和饵料转换效率有显著的影响，而对中国龙虾蜕壳后体长增长率和存活率影响并不明显。各种试验饵料中翡翠贻贝是饲养中国龙虾的最好饵料，其次是牡蛎、杂虾、杂蟹、杂鱼只能作为辅助性饵料，配合饲料的某些成分及其适品性、诱食性尚需改善和提高。     

Behavior and the Crustacean Molt Cycle: Changes in Aggression of Homarus americanus

The phase of the molt cycle affects dominance status and the performance of agonistic acts in individual juvenile lobsters (Homarus americanus). Lobsters in the midphase of proecdysis are more aggressive than those in intermolt; the latter are more aggressive than lobsters in early or late proecdysis and those in postecdysis.     

甘蔗螟虫生物防治策略展望

综述了甘蔗螟虫生物防治的主要策略及研究进展,并探讨了运用RNA干扰技术防治甘蔗螟虫的新策略,为通过转基因技术创制抗甘蔗螟虫新种质提供理论参考。     

Courtship in Spiders without Prior Sperm Induction

Experiments with a lycosid spider demonstrated that courtship behavior is displayed by males independently of whether sperm induction had occurred following the final molt. Contrary to earlier suggestions, proprioceptive feedback from sperm-filled palps is not essential for the onset of reproductive display.     

苯甲酰基脲类和肼类昆虫生长调节剂对棉铃虫的生物活性

研究了作用机制完全不同的苯甲酰基脲类（氟铃脲）和双苯甲酰基肼类（抑食肼和虫酰肼）昆虫生长调节剂（ＩＧＲ）及其混用对棉铃虫的生物活性和作用方式。供试３龄幼虫经氟铃脲点滴处理后,逐渐表现活动缓慢、反应迟钝、取食减少,最终死亡。死亡幼虫体壁薄而易破,头部背面呈现明显突起的白色透明水泡状（易破体并有体液流出）,部分虫体黑化,表现明显的蜕皮障碍。３龄幼虫经抑食肼处理后,最先也表现为行为迟缓、食量减小,最终死亡的幼虫虫体缩小并发黑,部分存活的幼虫２ｄ后即蜕皮。氟铃脲与抑食肼混合处理后,部分试虫呈现氟铃脲的中毒症状,部分试虫则表现抑食肼中毒症状,少量个体两种症状并发。氟铃脲对棉铃虫３幼虫的ＬＤ５０值（点滴法）和１龄幼虫的ＬＣ５０值（叶片法）分别为０．７４３４μｇａ．ｉ．／头和２．０５９２ｍｇ／Ｌ,表现出很强的触杀作用和胃毒作     

蒿柳雌株与雄株在高温胁迫下的生理差异及其变异

利用人工气候箱模拟高温环境,研究40 ℃/30 ℃(白天温度/晚上温度)处理下蒿柳雌株与雄株叶片电导率(EC)、超氧阴离子自由基(O·-2)产生速率、渗透调节物质含量以及抗氧化物酶活性的差异,分析各生理指标在雌株与雄株间的变异系数(VC)及分化系数(VST)。结果表明:高温胁迫下,蒿柳EC值、O·-2产生速率显著上升,但雌株EC值和O·-2产生速率显著大于雄株;脯氨酸(Pro)含量、可溶性蛋白(SP)含量显著升高,但雄株的渗透调节物质含量显著高于雌株;超氧化物歧化酶(SOD)活性、过氧化氢酶(CAT)活性、抗坏血酸过氧化物酶(AsA-POD)活性显著上升,过氧化物酶(POD)活性显著下降,但雄株的4种酶活性显著高于雌株。高温处理下,蒿柳雌株与雄株各生理性状的变异系数(VC)较为接近,说明各生理性状在雌性个体与雄性个体间的变异较为一致。各生理性状的平均分化系数(VST)为17.06%,说明高温胁迫下各生理性状在雌、雄株间的变异小于雌、雄株内(无性系之间)的变异。综上所述,高温胁迫下蒿柳无性系在生理性状上存在丰富的变异,但雄株具有较强的调节、适应能力。因此,在育种工作中适当多选择雄株优树,有助于获得耐热性强的新种质。      

双孢菇培养料工厂化发酵过程中微生物及物质变化研究

[目的]研究双孢菇培养料工厂化发酵过程中的微生物及物质变化规律。[方法]在培养料发酵过程中的几个主要时期采样,研究微生物数量、总氮和硝态氮、总糖和还原糖、含水量、pH值等指标的变化。[结果]随着培养料发酵的进行,细菌、放线菌和霉菌三大类微生物的数量均表现为先下降后上升的趋势,总氮含量和pH值表现为上升趋势,含水量、硝态氮含量和总糖含量则表现为逐渐下降的趋势。发酵期间培养料中的还原糖呈上下波动,发酵结束后含量略有上升。[结论]得到了工厂化培养料发酵过程中微生物和部分理化指标的变化规律,为双孢菇培养料高效发酵技术研究提供理论依据。     

TT基因型龙桑选育的研究

本试验是在1989年试验的基础上进行的,为了得到具有纯合的控制龙桑曲枝性基因(TT)的植株,对1989年获得的T型苗以天然授粉的方法进行测交,在已开花的39株中,发现有4株的基因型为TT.今后,由这些具有TT基因型的植株上所获得的种子育苗时,所获得的全部幼苗都将表现出曲枝性的特征.因而简化了龙桑苗木的繁殖方法,并可以比较容易地大批量的获得龙桑苗木.     

小井沟生态园区药用花卉植物资源调查

对呼和浩特市小井沟生态园区的药用花卉植物的调查和分析,结果显示在野生花卉植物中具药用价值的有53科、143属、253种,其中,菊科种类最多,共19属36种,占总种数的14.22%,其次是豆科12属,28种,占总种数的11.06%;其中清热药中所含的科数最多,共19科71种,占总数的28.06%;蒙医专用植物5科6种,占2.37%;并提出了保护及利用的途径。     

RH 5849, a Nonsteroidal Ecdysone Agonist: Effects on Larval Lepidoptera

The ecdysone agonist RH 5849 (1,2-dibenzoyl-1-tert-butylhydrazine) causes the premature initiation of molting at all stages of larval development of the tobacco hornworm, Manduca sexta. This phenomenon occurs without an increase in the endogenous ecdysone (20-hydroxyecdysone) titers. RH 5849 likewise provokes the initiation of molting in larval abdomens in the absence of a source of endogenous hormone. Although substantially less active than 20-hydroxyecdysone in vitro, RH 5849 was 30 to >670 times as active as the authentic molting hormone in bioassays with isolated larval abdomens or intact hornworms. This reversal in potency can be attributed to the superior transport properties and metabolic stability of RH 5849 relative to 20-hydroxyecdysone. Thus RH 5849 and its analogs are relatively persistent ecdysone agonists that halt feeding in larval lepidoptera by forcing an ultimately lethal, developmentally premature molt.     

利用wx基因分子标记快速鉴定糯性小麦

为了加快培育糯性小麦新品种,联合运用wx-B1基因的STS-PCR标记及wx-A1、wx-D1基因的SSR标记对济麦22×Waxy杂交组合F3代群体的131个单株进行wx基因型鉴定。结果发现：在131株F3代分离群体材料中,单缺失wx-A1a或wx-B1a或wx-D1a基因的材料分别为69、29、35株,分别占52.7%、22.1%和26.7%;同时缺失wx-B1a和wx-D1a基因的材料为10株,占7.6%;同时缺失wx-A1a和wx-B1a基因的材料为13株,占9.9%;未发现同时缺失wx-A1a和wx-D1a基因单株及wx-A1a、wx-B1a和wx-D1a基因全部缺失的单株。     

拔节和挑旗期缺磷对两小麦品种体内磷分配的影响

 采用石英砂培养方法,研究了拔节和挑旗期缺磷对大穗型小麦CA9325和多穗型晋麦2号（JM2）生长后期体内磷分配和成熟期磷利用效率的影响。结果表明,随着生长的延续,两品种供磷植株的主茎、有效分蘖和整株中的磷含量均呈"S"型增加,峰值在灌浆期。两品种所有处理的植株主茎中的磷在整株中所占比例不断增加,而无效分蘖和根系中的磷所占比例不断下降。两品种缺磷植株的有效分蘖中磷含量也呈下降趋势;对照CA9325主茎的籽粒含磷量及其在主茎中所占比例高于有效分蘖;而对照JM2主茎的籽粒含磷量低于有效分蘖,这与二者分属不同穗型小麦有关。缺磷的两品种主茎和有效分蘖营养器官和颖壳中的磷含量均低于同期的对照植株,使得籽粒中磷占主茎和有效分蘖中磷的比例高于对照。尽管如此,主茎和有效分蘖的籽粒含磷量低于对照;到成熟期,两次缺磷均显著降低两品种的籽粒产量。供磷的CA9325磷吸收效率和各处理的CA9325的收获指数均高于JM2,但前者各处理的磷利用效率低于后者。对两品种小麦体内磷利用的差异进行了讨论。     

红掌茎基腐病病原鉴定

 1996～1997年云南省热带作物科学研究所1～2年生地栽红掌发生了严重的茎基腐病,致使根、茎、叶柄变褐,叶片黄化,叶柄脱落,植株枯死。从病组织和土壤基质中分别分离到40和33个分离物,经鉴定寄生疫霉Phytophthora parasitica,光孢镰刀菌Fusariumoxyspo-rum为红掌茎基腐的致病菌。