低剂量快中子对角倍性蚜世代（虫袋）效应的研究

本文通过对角倍蚜性蚜世代（虫袋）的低剂量快中子辐射处理,来探索提高角倍产量的新途径,并提出适宜的辐射剂量和方法,研究表明,角倍性蚜世代（虫袋）经辐射处理后,在每虫袋平均产干母个数、结部数、产倍数、单倍均重方面,与对照组相比,以10^6剂量辐射处理组的效应最佳。但方差分析表明差异不显著。     

γ射线辐射杉木压缩木材的固定和蠕变(英文)

为了探讨木材压缩变定固定的机理 ,该研究对杉木压缩木材进行γ射线辐射处理 ,射线辐射剂量分别为 0 (作为对照试材 ) ,10 3 ,5× 10 3 ,10 4 ,5× 10 4 ,10 5,5× 10 5,10 6,5× 10 6Gy ,然后测定和讨论了γ射线辐射杉木压缩木材的重量损失率、平衡吸湿含水率 (EMC)、吸湿回复率 (RSA)和吸水回复率(RSW )、绝干状态下和吸湿解吸过程中的蠕变。该研究表明 :γ射线的辐射剂量对杉木压缩木材的重量损失率、EMC、RSA、RSW有重要的影响 ,当辐射剂量超过 10 6Gy后 ,试材的重量损失率和EMC显著增大 ,RSA和RSW显著下降 ;另外 ,随着γ射线辐射剂量的增大 ,绝干状态和吸湿解吸过程中杉木压缩木材的瞬时柔量和蠕变柔量均呈增大趋势 .从该研究结果可以推测 ,当γ射线辐射剂量较大时 ,特别当辐射剂量在 5× 10 6Gy左右时 ,杉木压缩木材的细胞壁中发生了降解反应或非结晶化反应 .而且 ,该研究证明了压缩木材细胞壁主成分发生的降解反应能够使木材压缩变定得到一定程度的固定     

CPV-Bt对湖南马尾松毛虫的药效试验

以湖南马尾松毛虫发生地采集的马尾松毛虫为试验材料，选用CPV、Bt 2种微生物复配后对其进行室内药效试验，结果表明：Bt对越冬代松毛虫前12d死亡率的影响显著，死亡率与Bt浓度呈正比，Bt浓度为6×10^7个芽孢／mL时，死亡率可达70．36％；Bt使用浓度为5×10^6芽孢／mL时，第一代松毛虫（群体饲养）处理6d平均死亡率可达70．41％，Bt使用浓度为1×10^7芽孢／mL时，平均死亡率可达75．09％；CPV对越冬代松毛虫处理12d后残留种群带毒率影响显著，带毒率与CPV浓度呈正比，当CPV浓度为2×10^5个多角体／mL时，其带毒率可达53．68％；复配药荆按其对第一代松毛虫（单虫饲养）的药效（前6d死亡率）可分为5类，其平均药效（死亡率）最高达100％，最低的仅为43．12％；CPV-Bt复配药刺防治马尾松毛虫的越冬代和第一代，若只需达到70％杀虫率和50％残留种群带毒率水平，越冬代宜选用2×10^5个多角体／mL＋6×10^7个芽孢／mL，第一代宜选用5×10^4个多角体／mL＋1×10^7个芽孢／mL。     

白足蚜小蜂对桃蚜的取食和寄生功能反应及搜寻效应

为评估白足蚜小蜂Aphelinus albipodus对桃蚜Myzus persicae的防控效果,在室内测定了白足蚜小蜂对不同发育阶段桃蚜的功能反应和搜寻效应,并对种内干扰和分摊竞争强度进行了比较。结果表明:白足蚜小蜂对不同发育阶段桃蚜的取食量和寄生量均随着蚜虫密度增加而增加,取食量和寄生功能反应均符合HollingⅡ模型。白足蚜小蜂对桃蚜的理论最大取食量2.809头,瞬时攻击率0.218,处理时间0.023 d;白足蚜小蜂对3～4日龄桃蚜寄生量最大,为47.62头,寄生瞬时攻击率0.723,处理时间0.021 d。搜寻效应均随蚜虫密度的增加而下降,且与蚜虫密度呈负相关。白足蚜小蜂个体之间存在种内干扰作用,随着自身密度增加,单头寄生率相对下降,分摊竞争强度增大,干扰效应符合Hassell-varley模型。由功能反应、种内干扰等指标可见白足蚜小蜂对桃蚜具有较好的防控作用。     

引进日本花角蚜小蜂试验

1988年作者在惠东试点,对从日本冲绳引进的花角蚜小蜂进行了形态、生物学特性和繁育条件的研究。经4代繁育试验表明,此蜂对马尾松上的松突圆蚧寄生能力强,寄生率高,特别是能寄生叶鞘内的雌蚧。同时,还可以看出,温度、营养和光照是影响繁蜂的主要因子。     

钴60辐射红掌组培材料的实验初报

用60Co 0.5-6 5Gy剂量辐射处理红掌6个品种的不定芽和愈伤组织材料,并进行组培试验,结果表明辐射愈强,参试材料受抑制程度愈大;不同红掌品种对辐射的敏感性不同;初步看出60Co对不定芽半致死剂量为30-40Gy,对愈伤组织半致死剂量为10-20Gy。     

不同剂量~(60)Co-γ射线对凤丹种子生根、出苗及幼苗生长的影响

以凤丹(油用牡丹)的干种子、湿沙层积的湿种子为辐射诱变材料,通过不同剂量60Co-γ射线照射处理,研究对种子生根、幼苗生长及幼苗变异情况的影响。结果表明:凤丹干、湿种子的生根率、主根长度≥4 cm种子的百分率、须根的比率均表现为低剂量促进、高剂量抑制的趋势。低剂量辐射处理干、湿种子,均表现为初萌期提前,出苗指数和出苗率提高;随着剂量增加,初萌期延迟,出苗指数和出苗率降低。根据出苗率计算出凤丹干、湿种子的半致死辐射剂量分别为18.94 Gy和9.51 Gy。干种子中低辐射剂量(10 Gy)处理的苗高与对照无显著差异;当辐射剂量超过20 Gy时,苗高随辐射剂量的增大而降低。各处理幼苗的茎粗与对照均无显著差异。辐射对湿种子幼苗高度的影响与干种子相似,但湿种子耐辐射能力稍差,辐射超过6 Gy,苗高即显著低于对照;而较高辐射处理(10—20Gy)的湿种子幼苗茎粗显著低于对照。干、湿种子的幼苗变异率均表现为随辐射剂量加大逐渐增大的趋势。60Co-γ射线对凤丹幼苗的诱变效应主要表现为小叶退化和叶色变化,且随辐射剂量增大,幼苗也会出现叶片畸形、叶尖枯萎、茎徒长等畸变。     

应用快中子处理角倍蚜对后代生育及产结倍作用的初步研究

五倍子蚜虫的瘿外世代死亡率较高,影响五倍子产量的提高.本文报道了1987～1988年应用快中子辐照角倍好的试验结果,倍蚜能够完成生活周期,减少越冬死亡数,提高春迁蚜的羽化率,增加结倍数.辐照剂量为10~(16)通量的处理组,增产率最高,达108.3%.     

我国观赏植物辐射诱变育种研究进展

文章论述了国内外观赏植物辐射诱变育种研究进展，详细阐明我国近年在诱变源、辐射诱变机理、辐射效应、诱变材料、辐射剂量与变异率的关系等方面研究概况，提出今后辐射育种研究的主要方向。     

三个菊花品种花器官愈伤组织辐射效应的研究

用辐射剂量为10、15、20Gy的60Coγ射线对金莲、白矮生和矮红3个小花型夏菊品种的舌状花和管状花产生的愈伤组织进行辐射处理,研究了辐射处理对愈伤组织褐化率、分化率以及分化芽的数量的影响.结果表明:γ射线对3个品种不同来源愈伤组织的褐化、分化能力均有影响.随着辐射剂量的增加,不同来源的愈伤组织的褐化程度均加重,而分化能力则减弱.此外,不同基因型和不同来源的愈伤组织,对γ射线敏感性也有差异,矮红品种的愈伤组织最敏感,舌状花产生的愈伤组织比管状花产生的愈伤组织辐射敏感性强.     

Parasitism byMeteorus rubens onAgrotis ipsilon as affected by supplementary food and kairomone, field studies

Field experiments in clover field showed that releasing of 10 matedM. rubens females/m², increased parasitism amongA. ipsilon larvae from 16.7% at 0 to 43,3% after 10 days. Also, releasing 10 females/m² after spraying 3% molasses in tomato field increased parasitism from 4% at 0-day to 27.5% after 10 days amongA. ipsilon larvae. Spraying molasses and kairomone together on maize plants, increased markedly the rate of parasitism amongS. cretica larvae comparing with parasitism obtained when each of them was sprayed alone. The release ofM. rubens in a rate of 10 females/m² after spraying molasses and kairomone induced a significant increase in the rate of parasitism amongS. cretica larvae after 10 and 15 days compared to releasing 3 or 4 females of the parasitoid. A significant increase in parasitism amongS. cretica larvae on tomato after 10 and 15 days was recorded whenM. rubens was released at the rates of 5 and 10 females/m², after spraying molasses and kairomone, compared to other treatments.     

释放方法和种源对花绒寄甲防治光肩星天牛效果的影响

为有效利用花绒寄甲Dastarcus helophoroides防治光肩星天牛Anoplophora glabripennis,在武威绿洲区开展试验研究.通过采用不同释放方式、不同时期、释放不同数量和种源的花绒寄甲,进行防治效果比较.结果表明:直接释放和打孔释放的防治效果无差异;6月初释放的防治寄生率比9月下旬释放的高...     

黄粉甲饲养方式对川硬皮肿腿蜂人工繁育的影响

以花鸟市场购买的普通黄粉甲幼虫和湖南省林业科学院培养的川硬皮肿腿蜂为试材,就黄粉甲的饲养方式对川硬皮肿腿蜂人工繁育的影响进行了研究。结果表明:20、24、28℃3种温度条件下培养的黄粉甲的老、熟、幼虫体长、初化蛹时间及蛹个体大小均有差异,随着饲养温度的降低,黄粉甲老、熟、幼虫体形变长、蛹的个体变大、初化蛹时间延长;3种温度下所化黄粉甲蛹按蜂蛹比1∶1接入川硬皮肿腿蜂后,其寄生率有显著性差异,而子代出蜂量无显著差异,20℃条件下所化蛹的寄生率和出蜂量分别较其它处理组提高了12%~22%和3~5头;在相同温度下饲喂葡萄糖的黄粉甲组与没有饲喂葡萄糖组相比,其肿腿蜂寄生率和子代数量均无显著性差异。     

川硬皮肿腿蜂与中华甲虫蒲螨协同防治天牛类蛀干害虫技术研究

根据川硬皮肿腿蜂(Scleroderma scichuanensis Xiao)和中华甲虫蒲螨(Pyemotes zhonghuajia)的作用特点和优势,主要以协同防治天牛类蛀干害虫为例,进行野外释放及防效研究。结果表明:川硬皮肿腿蜂和中华甲虫蒲螨对天牛均有控制作用,两者的交互作用,平均寄生率为52.8%,虫口减退率为54.62%,防治效果均优于农药;二者作用时期不同,蒲螨对低龄幼虫寄生率高,肿腿蜂对中高龄幼虫寄生率高。在防治时,应根据两者的作用特点和优势,在不同时间(龄期)进行2种天敌的先后释放可达到较高的寄生率和虫口减退率。     

低温贮藏对白蛾黑基啮小蜂羽化及出蜂的影响

白蛾黑基啮小蜂(Tetrastichus nigricoxae Yang)在柞蚕(Antheraea pernyi Guerin-Meneville)蛹内分别发育至老熟幼虫期、预蛹期和蛹中期,再于5 ℃分别冷藏7,14,21 d后让其正常发育至羽化出蜂,测定低温贮藏对该寄生蜂羽化及出蜂的影响.结果表明白蛾黑基啮小蜂于5...     

Impact of neem and chinaberry fruit extracts on the pest/parasitoid (Pieris rapae/Hyposoter ebeninus) interactions

A new technique was performed to simulate exposure of the host Pieris rapae larvae to both botanical treatment and the parasitoid Hyposoter eheninus in different sequences. It was found that: host larvae subjected to both parasitoid and 1?% neem treatment showed significant or insignificant reductions both in pupal formation as well as adult emergence percentages when treatment preceded or followed parasitism, respectively. Both neem treatments revealed significant prolongation in the development of unparasitized and parasitized larvae (on average 4 to 5 days delay), whereas chinaberry caused significant prolongation only among parasitized larvae (on average 2.7 days delay in egg-larval duration). Fate of parasitism among untreated hosts was found to be faster than among neem-treated ones. Parasitism percentages among 1 and 0.5?% neem-treated third instar host larvae held 7 days before parasitism reached 3 and 2 times that achieved among those reared on untreated diet for the same period, ­respectively. It was concluded that prolongation of the preferred target instars of the host, due to neem treatments, increased the chance for parasitism. Nevertheless, treatment with neem at the LC₅₀ level exhibited a great reduction in parasitoid progeny. However, a lower concentration (LC₂₅) could reasonably potentiate parasitism without drastic losses in parasitoid emergence.     

The effect of oviposition experience of adult Microplitis pallidipes parasitoids on discrimination between nucleopolyhedrovirus-infected and healthy Spodoptera litura larvae

Using multiple pest-mortality sources is a basic tenet of IPM, but they may not always be compatible. To that end, we examined compatibility of parasitism and nucleopolyhedrovirus (NPV) infected. Specifically, we examined the effects of prior oviposition experience by Microplitis pallidipes on its ability to distinguish NPV-infected from healthy larvae of Spodoptera litura. We found that time spent searching for hosts was significantly lower, while the number of attacks, percentage of first attacks, and parasitism rate were all significantly higher in healthy versus virus-infected hosts for parasitoids that had experienced healthy hosts. Meanwhile, parasitoids that had experienced infected hosts spent significantly more time searching for infected hosts starting on day 2. For these parasitoids, the number of attacks, percentage of first attacks, and parasitism rate were all significantly lower from day 2 in virus-infected versus healthy larvae. We found no significant differences between parasitoids without experience versus ones experienced with infected hosts in search time for infected hosts, number of infected host attacks, or percentage of first attacks on infected hosts. In comparison, parasitoids that had experienced healthy hosts spent less time searching for healthy hosts than parasitoids without experience, and displayed a higher frequency of attack on healthy hosts and a higher percentage of first attacks on healthy hosts. Experience with healthy larvae aided parasitoids in distinguishing healthy from virus-infected larvae, but experience with virus-infected larvae did not convey the same discrimination. This information provides a better understanding of how to integrate NPV applications with naturally occurring parasitism for this pest in crops.     

白蛾周氏啮小蜂可持续控制美国白蛾的研究

利用白蛾周氏啮小蜂防治美国白蛾,在老熟幼虫期和化蛹初期分别放蜂1次,放蜂量为美国白蛾幼虫数量的5倍,连续放蜂防治两代美国白蛾,就可将其种群数量有效控制,使有虫株率降到1.25%,天敌的总寄生率达到92.67%。放蜂防治后连续5年,共追踪调查10代美国白蛾的发生情况,发现这种小蜂具有良好的持续控制效果。美国白蛾在防治后第2年至第5年有虫株率均保持在0.1%以下的低水平,天敌的寄生率仍高达92%,表明持续控制作用十分显著。研究中,还对我们计算出的回归模型y=-51.60795 77.47512lgx进行了实际检验。结果显示,利用该模型计算出的多种天敌的总寄生率与实际调查所得的总寄生率之间没有显著差异,因此,该模型可以用于调查天敌的寄生率,能够大大节约工作量,利于生产单位实际应用。     

Predicting the number of nymphal instars plus new-generation adults of the Sunn Pest from overwintered adult densities and parasitism rates

The present study evaluated the effect of overwintered adult density and egg and adult parasitism rates on the new-generation population densities of the Sunn Pest (Eurygaster integriceps Put.) under field conditions. We quantified the abundance of overwintered adult densities and egg and adult parasitism rates in 20 one-ha unsprayed wheat fields in southeastern Turkey to assess their impact on nymphal instars, plus new-generation adult densities. The number of overwintered adults per square meter and the percent of egg parasitism rates were positively and negatively correlated with new-generation densities of the Sunn Pest, respectively. The results of multiple regression analysis produced the equation Y = 15.037 + 8.287 OW (overwintered adult) − 0.235 egg PR (parasitism rate). The findings suggest that the egg parasitoids may suppress nymphal instars plus new-generation adult densities of the Sunn Pest. The findings also suggest that the present formula can be used to determine the spraying areas in which densities reach economic threshold for the integrated Sunn Pest management program in wheat fields in Turkey.     

新物种——青檀绵叶蚜寄主及天敌种类调查

青檀绵叶蚜是危害青檀的蚜虫新种。该文报道了该虫的寄主和天敌,根据试验结果:青檀是该虫的唯一适合寄主;调查到4科6属8种捕食性天敌,以异色瓢虫Leis axyridis(Pallas)、中华草蛉Chrysoperla sinica Tjeder、大草蛉Chrysopa pallens(Rambur)、黑带食蚜蝇Epistrophe balteata DeGeer、中华狼蛛Lycosa sinensis Schenkel数量大,捕食量大。除1种寄生螨外,未发现其他寄生性天敌。