Effectiveness of a naturally derived insecticide, spinosad, against the pine processionary moth Thaumetopoea wilkinsoni Tams (Lepidoptera: Thaumetopoeidae) under laboratory conditions

The pine processionary moth Thaumetopoea wilkinsoni Tams is a serious pest on pine trees in southwestern Turkey. The efficacy of a naturally derived insecticide, spinosad, on fourth-fifth instar larvae of T. wilkinsoni was studied under laboratory conditions. The product exhibited strong larvicidal activity and at doses above 5 mg litre(-1) caused > 90% mortality in the fourth-fifth larval stages of the species after 72 h. At 72 h the LD50 and LD90 values were 3.26 and 5.69 mg litre(-1) respectively. The results showed that spinosad is highly effective on T. wilkinsoni larvae.     

Native entomopathogenic nematodes isolated from Turkey and their effectiveness on pine processionary moth,Thaumetopoea wilkinsoni Tams

Two native entomopathogenic nematodes were isolated from soil samples in Eastern Mediterranean region of Turkey and characterized based on 28S rDNA region. BLASTN homology and phylogenetic analysis of SK17 and SK-71 isolates indicated 98% and 99% identity to Steinernema affine and Steinernema feltiae, respectively. The results were constructed by neighbour-joining and bootstrap tree methods. Efficacy of S. affine (SK-17 strain) and S. feltiae (SK-71 strain) was tested against the larvae of pine processionary moth, Thaumetopoea wilkinsoni Tams, and remarkable mortality rates were obtained. Both strains caused complete mortality upon application of 500 IJs in foliar tests. However, the same strains caused 30% and 33% mortality at 80 IJs/cm² in soil applications. It was concluded that these native strains could be considered as potential biocontrol agents for reducing the damage caused by T. wilkinsoni larvae.     

牛至精油及其主要成分香芹酚和百里酚对16种植物病原真菌的抑制活性

为评价牛至精油及其2种主要成分香芹酚和百里酚在植物真菌病害防治方面的应用前景,采用菌丝生长速率法和孢子萌发法测定3种物质对16种植物病原真菌菌丝生长和孢子萌发的抑制活性,并采用黄瓜子叶法测定其对黄瓜灰霉病的防治效果。结果表明,牛至精油在500 mg/L浓度处理下可完全抑制番茄早疫病菌Alternaria solani、黄瓜灰霉病菌Botrytis cinerea和小麦根腐病菌Bipolaris sorokiniana等12种植物病原真菌的菌丝生长,对棉花黄萎病菌Verticillium dahliae的菌丝生长抑制率也达到97.66%。牛至精油对这13种病原真菌的EC₅₀在83.09~236.58 mg/L之间,香芹酚和百里酚对这13种病原真菌的毒力均高于牛至精油,其中香芹酚对黄瓜灰霉病菌、油菜菌核病菌Sclerotinia sclerotiorum、小麦全蚀病菌Gaeumannomyces graminis、棉花黄萎病菌和小麦茎基腐病菌Fusarium pseudograminearum菌丝生长的毒力较强,EC₅₀分别为9.09、22.45、24.28、28.40和28.80 mg/L;百里酚对黄瓜灰霉病菌和小麦全蚀病菌菌丝生长的毒力较强,EC50分别为21.32 mg/L和27.08 mg/L。香芹酚和百里酚对棉花黄萎病菌、玉米大斑病菌Setosphaeria turcica、苦瓜枯萎病菌Fusarium oxysporum f.sp.momordicae、黄瓜灰霉病菌和黄瓜炭疽病菌Colletotrichum orbiculare的孢子萌发亦有较强毒力,其EC₅₀为3.78~289.07 mg/L。1 000 mg/L牛至精油对黄瓜灰霉病的预防效果与400 mg/L嘧霉胺悬浮剂的预防效果无显著差异;500 mg/L百里酚对黄瓜灰霉病的预防效果和治疗效果均与400 mg/L嘧霉胺悬浮剂的效果相当,而香芹酚的治疗效果显著优于400 mg/L嘧霉胺悬浮剂。表明牛至精油及其主要成分香芹酚和百里酚的抑菌谱广且活性强,具有作为植物源杀菌剂的开发应用潜力。     

Impact of defoliation by the pine processionary moth (<Emphasis Type="Italic">Thaumetopoea pityocampa</Emphasis>) on radial,height and volume growth of calabrian pine (<Emphasis Type="Italic">Pinus brutia</Emphasis>) trees in Turkey

An outbreak of the pine processionary moth (PPM),Thaumetopoea pityocampa Schiff. (Lepidoptera: Thaumetopoeidae), began in spring 1998 and lasted 5 years in aPinus brutia Ten. (Calabrian pine) stand. Tree volume and volume elements increments were examined throughout a PPM outbreak cycle from 1981 to 2003, for an even aged, pure, undisturbed, young Calabrian pine stand. Tree ring chronologies of ‘control’ Calabrian pine, which was not defoliated by PPM during the period of 1998–2003, were used to estimate potential growth characteristics in the ‘host’ Calabrian pine (moderate and high defoliation groups) for current and past outbreaks. Increment cores were collected from 70 host and 78 control dominant or co-dominant trees and annual radial growth indices from 1981–2003 were calculated for each defoliation group in a 41 point sampling. Growth functions were defined as the cumulative sum of radial, height, and volume increment, and graphically compared between host Calabrian pine (3 moderate and one high), four control Calabrian pine and one host Crimean pine (Pinus nigra Arnold) sample trees. At least three severe outbreak periods were identified (from 1981–86; 1992–97; and 1998–2003), much of the study area being severely affected by PPM. Tree ring evidence suggests that large scale (in 1981, 1992, 1998) and partial (in 1988) outbreaks occurred in the study area. Negative inflections of host radial growth curves relative to control height and volume indicated PPM activity. The periodic average diameter growth reductions (in %) in 1981, 1988, 1992 and 1998, respectively, were 0, 13, 5 and 0 for control, 12, 8, 7 and 2 for moderate, and 18, 5, 0 and 7 for high defoliation groups. Outbreaks appear to be associated with dry winter and spring weather prior to the autumn and winter in which feeding occurs. http://www.phytoparasitica.org posting Sept. 28, 2004.     

光果莸挥发油的化学成分及其对两种仓储害虫防治作用

探究光果莸挥发油的化学组成及其对两种仓储害虫的防治效果。利用GC/MS分析光果莸挥发油的化学成分,通过触杀、熏蒸和驱避试验评价光果莸挥发油对两种昆虫的生物活性。结果表明,光果莸挥发油中共鉴定出20种化合物,占总成分的94.08%,主要化合物为反乙酸松香芹酯(36.1%),柠檬烯(23.1%),β-蒎烯(13.6%),邻异丙基甲苯(5.6%),桃金娘烯醛(3.3%)。光果莸挥发油对烟草甲和嗜卷书虱表现出一定触杀作用(半数致死量LD_(50)分别为24.90μg/头和2.74μg/cm~2)和熏蒸活性(半数致死浓度LC_(50)分别为37.62 mg/L air和9.88 mg/L air),且光果莸挥发油对嗜卷书虱具有明显的驱避活性。结果提示,光果莸挥发油具有进一步开发为植物源杀虫剂的潜力。