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111.
【目的】本研究旨在明确韭菜迟眼蕈蚊Bradysia cellarum成虫行为活动的昼夜节律,为其室内饲养、行为学研究和研发精准、高效的监测与防控新技术提供依据。【方法】室内系统观察记录了韭菜迟眼蕈蚊成虫羽化盛期求偶、交配、产卵、移动与静息等行为的昼夜节律,分析了其特定行为的时间分配特征。【结果】韭菜迟眼蕈蚊成虫的运动行为和静息行为白天和黑夜均有发生,夜间的繁殖行为(求偶、交配和产卵)频次高于白天的,各时间点的移动、静息和繁殖行为频次占比间均具有显著性差异。韭菜迟眼蕈蚊雌雄成虫的求偶节律相同,一天中求偶有两次高峰,分别出现在3:00和7:00。韭菜迟眼蕈蚊雌雄成虫的交配节律与雌成虫的产卵节律相似,雄成虫移动行为频次占比的峰值时刻均出现在3:00时,雌成虫移动行为频次占比的峰值时刻则出现在19:00时。雌雄成虫静息行为的频次占比均无明显昼夜节律高峰。在日时间分配上,雌、雄成虫以静息行为的时间占比最多,分别为89.53%和89.90%;求偶行为的时间占比最少,分别为0.56%和0.89%。雌雄成虫各行为的日时间占比差异不显著。【结论】韭菜迟眼蕈蚊成虫的求偶、交配、产卵、移动和静息行为具有明显...  相似文献   
112.
《Journal of Asia》2014,17(2):169-174
The robber fly, Promachus yesonicus, a predator of scarab adults and larvae was observed on golf clubs in Korea to determine its seasonal activity, daily activity, and relationship to scarab adult activity. P. yesonicus adult density varied more than 10-fold among the four golf clubs where it was observed, with the most activity being at golf clubs with the most scarab adults in June and July. At Yongwon Golf Club P. yesonicus activity closely tracked Popillia quadriguttata activity and both peaked in late June and early July. The ratio of scarab adults (mostly P. quadriguttata):P. yesonicus adults was 8:1. On average mean of 7.5% of all P. yesonicus adults observed in visual surveys were holding captured prey. 50% of all captured prey was a scarab turf pest, P. quadriguttata. At Yongwon Golf Club, regression analysis indicates that P. quadriguttata activity explains 75% of the variation in activity of P. yesonicus. The potential impact of P. yesonicus on populations of P. quadriguttata and other scarab turf pests is discussed.  相似文献   
113.
森林-草原交错带土壤节肢动物群落多样性   总被引:5,自引:1,他引:4  
在河北北部的塞罕坝森林草原交错区进行了土壤节肢动物群落组成与多样性调查,共获得土壤节肢动物25类,10420头,分属于6纲24目.交错区地带土壤节肢动物群落优势类群为弹尾目和蜱螨目,常见类群有8类,稀有类群15类.群落的多样性分析表明,森林带的多样性指数(H′)、密度-类群指数(DG)和均匀度指数较大,而草甸草原带各种指数较小.pH值与土壤节肢动物的类群数关联度较大,而温度和含水量与土壤节肢动物的个体数关联度较大.  相似文献   
114.
Chinese jujube (Ziziphus jujuba), an economically important species in the Rhamnaceae family, is a popular fruit tree in Asia. Here, we surveyed and characterized simple sequence repeats (SSRs) in the jujube genome. A total of 436,676 SSR loci were identified, with an average distance of 0.93 Kb between the loci. A large proportion of the SSRs included mononucleotide, dinucleotide and trinucleotide repeat motifs, which accounted for 64.87%, 24.40%, and 8.74% of all repeats, respectively. Among the mononucleotide repeats, A/T was the most common, whereas AT/TA was the most common dinucleotide repeat. A total of 30,565 primer pairs were successfully designed and screened using a series of criteria. Moreover, 725 of 1,000 randomly selected primer pairs were effective among 6 cultivars, and 511 of these primer pairs were polymorphic. Sequencing the amplicons of two SSRs across three jujube cultivars revealed variations in the repeats. The transferability of jujube SSR primers proved that 35/64 SSRs could be transferred across family boundary. Using jujube SSR primers, clustering analysis results from 15 species were highly consistent with the Angiosperm Phylogeny Group (APGIII) System. The genome-wide characterization of SSRs in Chinese jujube is very valuable for whole-genome characterization and marker-assisted selection in jujube breeding. In addition, the transferability of jujube SSR primers could provide a solid foundation for their further utilization.  相似文献   
115.
木兰围场典型落叶松-杨桦混交林生物量及固碳能力   总被引:1,自引:0,他引:1  
以木兰林管局北沟林场内典型落叶松-杨桦混交林、落叶松人工林、白桦天然次生林、山杨天然次生林为研究对象,利用分层切割法和分层挖掘法对华北落叶松、白桦、山杨的生物量进行测定,并通过解析木进行了生长量的测定,从而建立生物量、生长量模型对林分的碳储量和固碳能力进行了估算。其研究结果表明:落叶松-杨桦混交林较落叶松人工林、白桦天然次生林、山杨天然次生林具有一定幅度的增产效益。落叶松-杨桦混交林中落叶松、白桦、山杨表现均优于各自的人工林或天然林,平均胸径分别高出6.7%、12.8%、4.1%,平均树高分别高出12.1%、1.4%、11.1%。落叶松-杨桦混交林中落叶松、白桦、山杨的固碳量增幅分别为29.74%、28.36%、34.52%;落叶松人工林固碳量增幅27.09%;白桦天然次生林固碳量增幅26.34%;山杨天然次生林固碳量增幅26.24%。落叶松-杨桦混交林中落叶松、白桦、山杨固碳量的增幅分别高于所对应树种的2.65%、2.02%、8.28%。  相似文献   
116.
117.
培养条件对茄链格孢产孢的影响   总被引:3,自引:0,他引:3  
茄链格孢Alternaria solani在体外培养条件下不产生或产生极少量的分生孢子。研究了培养基、菌丝损伤、紫外线照射和温度变化对7个茄链格孢菌株产孢的影响,发现这些处理方法对供试大多数菌株的产孢都有显著影响,确立了茄链格孢大量产孢的最优条件。利用优化后的条件对160株采自不同地区的茄链格孢进行体外诱导产孢,发现120株可大量产孢,占总数的75%,产孢量为1.26×104–5.03×104个/cm2。  相似文献   
118.
目的:研究回生口服液对晚期非小细胞肺癌患者血浆纤维蛋白原和血小板水平的影响。方法:选取2011年1月至2013年7月已被收治的112例晚期非小细胞肺癌患者按照知情同意原则随机分为治疗组(60例)和对照组(52例)两组,治疗组在支持、对症治疗的基础上口服回生口服液治疗,对照组仅给予支持、对症治疗,4周后观察两组患者经两种不同的治疗方案治疗后患者血浆纤维蛋白原及血小板水平变化。结果:治疗组经给药治疗后血浆纤维蛋白原及血小板水平与治疗前相近,差异均无统计学意义(P〉0.05);对照组经治疗后血浆纤维蛋白原及血小板水平较治疗前高,差异均有统计学意义(P〈0.05);治疗组给药治疗后血浆纤维蛋白原及血小板水平均较对照组低,差异均有统计学意义(P〈0.05)。结论:回生口服液可能是通过降低血浆纤维蛋白原及血小板的含量从而改善晚期非小细胞肺癌患者的血液高凝状态。  相似文献   
119.
《Fungal biology》2014,118(9-10):755-763
Morchella species are edible fungi in high demand and therefore command high prices in world markets. Phenotypic-based identification at the species-level remains inadequate because of their complex life cycles, minor differences and plasticity of morphological characteristics between species, and the lack of agreement between scientific and common names. In Patagonia–Argentina, morels are associated with native forests of Austrocedrus chilensis (Cordilleran or Chilean cypress) and Nothofagus antarctica (ñire) and several exotic conifers that were introduced from western North America. Little is known about their taxonomy and phylogenetic relationships with other species in the genus. This work focused on the identification of collections of Morchella from Patagonia and their phylogenetic relationships with other species from the Northern Hemisphere. The comparison was made by analysis of DNA sequences obtained from four loci: the nuclear ribosomal internal transcribed spacer region (ITS) and the partial RNA polymerase I gene (RPB1) for the complete collection; and ITS, RPB1, RNA polymerase II gene (RPB2), and translation elongation factor (EF1-α) for the species-rich Elata Subclade. Analyses of individual and combined data sets revealed that Patagonian morels belong to the Elata Clade and comprised three strongly supported species-level lineages from both Patagonian native forest, and exotic trees introduced from western North America. One lineage was identified as Morchella frustrata phylogenetic species Mel-2, which is known from the USA and Canada. The second lineage, which appeared to be ‘fire-adapted’, was identified as Morchella septimelata phylogenetic species (Mel-7), which is also known from the USA. This species was collected from burned native forests mainly composed of A. chilensis and N. antarctica but also Pseudotsuga menziesii (Mirb.) Blanco, which is native to western North America. The phylogenetic analyses suggested that the third species from Patagonia was nested within the species-rich Elata Subclade and represents a new species-level lineage (informally designated Mel-37) within Elata Clade. The present collections from Patagonia constitute the southernmost latitude from which Morchella has been reported to date. The identification of two Argentine morels as North American taxa is therefore a remarkable biogeographic pattern. In view of the hypothesis that the Elata Clade originated in western North America, we speculate that at least two of the lineages colonized South America from North America via long distance dispersal, migration or, more likely, they were introduced with the exotic tree species that they were collected near.  相似文献   
120.
The striped flea beetle, Phyllotreta striolata (F.) (Coleoptera: Chrysomelidae) is a key pest of crucifer vegetables in Southern China. The use of entomopathogenic nematodes (EPNs) within an integrated pest management approach may offer an effective and environmentally safe strategy to suppress outbreaks of this pest. In the present study, the efficacy of Steinernema carpocapsae All and Heterorhabditis indica LN2 for the control of P. striolata in the field was evaluated, as well as the combined application of EPNs and azadirachtin against the pest. Both nematode species were capable of reducing populations of the soil-dwelling stages of P. striolata, thus leading to a reduction of the adult populations and the associated shot-hole damage on the leaves. Nematode treatments also increased cabbage yields as compared to the control and azadirachtin treatments alone. Azadirachtin alone was not effective to prevent damage by P. striolata, but it could enhance the control effect of S. carpocapsae shortly after application. Osmotically treated infective juveniles (IJs) of S. carpocapsae All performed as well as untreated IJs.  相似文献   
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