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1.
桃小食心虫(Carposina niponensis Wals)是我国苹果、梨上的重要害虫,初孵幼虫在果面爬行片刻,即蛀入果内。幼虫能否入果,除受捕食性天敌和风雨等外界条件影响之外,与果实表皮组织有关系,蛀入果内幼虫的成活数量和生长情况亦受果肉组织及果实内含物的直接影响。因此,研究食料条件与桃小食心虫发生数量的关系,对提高该虫现有  相似文献   
2.
中国的散白蚁属及新亚属新种   总被引:1,自引:0,他引:1  
散白蚁(Reticulitermes)的名称,来源于浙江东阳一部分以防治白蚁为专业的农民,他们根据实践经验,积累了丰富的生态和防治知识,知道这类白蚁,缺乏大型巢窟,常集较小群体,散居于有树根和腐木的地下,一般危害房屋下部。在全世界来说,广布于温带及亚热带地区。本文对我国散白蚁属进行了系统的整理,把本属分设两个新亚属:额白蚁亚属(Frontotermes)和平额白蚁亚属(Planifrontotermes),前者分布偏于南方,后者偏于北方。记载4个新种,并分别订正长期存在着争论的4个老种。 散白蚁属与其近缘属——异白蚁属[Heterotermes Froggatt,1896(=Leucotermes Silvestri,1901)]极相似,但散白蚁属成虫有单眼,翅面脉网较显著,毛被稀少,兵蚁上唇舌形,有时尖锐,分布偏于北方。而异白蚁属成虫一般缺单眼,翅面脉网微弱,毛被较密而显著,兵蚁上唇尖锐,分布偏于热带,两者可以区别。  相似文献   
3.
斜纹夜蛾核多角体病毒病的研究   总被引:1,自引:0,他引:1  
本文报道斜纹夜蛾核多角体病毒病的实验室和田间试验结果。 多角体形状不规则,直径平均1.9微米。病毒粒子杆状,单个或成束存在。单个粒子大小为335×90毫微米,病毒束的直径140毫微米。生物测定结果表明,幼虫死亡率依多角体浓度和虫龄而变化,在25℃条件下,3龄幼虫的致死中浓度为1×105.3多角体/毫升。龄期相同时,幼虫死亡速度依多角体浓度和环境温度而变化。多角体喷洒到植物叶面后,数日内可以损失大部分感染力,损失的速度与阳光照射的时间长短以及多角体浓度有关。感染力的损失主要是由于紫外光的灭菌作用。病毒与苏云金杆菌同时感染没有增效作用。斜纹夜蛾核多角体病毒对小地老虎、黄地老虎、粘虫和家蚕无感染力。田间初步试验表明,应用病毒防治斜纹夜蛾是可能的。  相似文献   
4.
Auxin and abscisic acid (ABA) modulate numerous aspects of plant development together, mostly in opposite directions, suggesting that extensive crosstalk occurs between the signalling pathways of the two hormones. However, little is known about the nature of this crosstalk. We demonstrate that ROP‐interactive CRIB motif‐containing protein 1 (RIC1) is involved in the interaction between auxin‐ and ABA‐regulated root growth and lateral root formation. RIC1 expression is highly induced by both hormones, and expressed in the roots of young seedlings. Whereas auxin‐responsive gene induction and the effect of auxin on root growth and lateral root formation were suppressed in the ric1 knockout, ABA‐responsive gene induction and the effect of ABA on seed germination, root growth and lateral root formation were potentiated. Thus, RIC1 positively regulates auxin responses, but negatively regulates ABA responses. Together, our results suggest that RIC1 is a component of the intricate signalling network that underlies auxin and ABA crosstalk.  相似文献   
5.
ABSTRACT Central nervous system (CNS) of arachnids is still mysterious and has a rich unexplored field compare to what is known in insects or crustaceans. The CNS of the spider, Achaearanea tepidariorum, consists of a dorsal brain or supraesophageal ganglion and circumesophageal connectives joining it to the subesophageal mass. As the segmentation of the arachnid brain is still under discussion, we classify the brain as a protocerebral and tritocerebral ganglion depending on the evidences which generally accepted. The subesophageal nerve mass underneath the brain is the foremost part of the ventral nerve cord. All of this nerve mass is totally fused together, and forming subesophageal ganglia in this spider. In the brain, the nerve cells are packed in the frontal, dorsal and lateral areas, but are not absent from the posterior and ventral regions. In addition, the nerve cells of the subesophageal and abdominal ganglia are only restricted to the ventral and ventolateral regions. The CNS of the spider, Achaearanea tepidariorum is similar in feature to the Family Araneidae.  相似文献   
6.
7.
Abstract. The Dolichopodidae is a species‐rich dipteran group with almost 7000 described species. The monophyly of the subfamilies and their relationships remain largely unknown because the polarities of key morphological characters are unclear and molecular data are available only for 9 of the 19 proposed subfamilies. Here we test whether molecular data from two nuclear (18S, 28S) and four mitochondrial (12S, 16S, Cytb, COI) genes can resolve the higher‐level relationships within the family. Our study is based on 76 Oriental species from 12 dolichopodid subfamilies and uses eight species of Empididae and Hybotidae as outgroups. Parsimony and likelihood analyses confirm the monophyly of the Dolichopodidae, as well as the monophyly of five of the ten subfamilies represented by more than two species [Sympycninae, Sciapodinae, Dolichopodinae, Hydrophorinae (excluding tribe Aphrosylini), Neurigoninae]. There is strong support for restoring the tribe Aphrosylini as a separate subfamily Aphrosylinae. The monophyly of Medeterinae, Peloropeodinae and Diaphorinae is dependent on which tree reconstruction technique is used, how indels are coded, and whether the fast‐evolving sites are excluded. Overall, we find that our sample of Oriental species is largely compatible with the subfamily concepts that were developed for the northern temperate fauna. However, our data provide little support for relationships between the subfamilies. Branch lengths, saturation, and distance plots suggest that this is probably the result of the rapid origin of dolichopodid subfamilies over a relatively short time. We find that genera that are difficult to place into subfamilies based on morphological characters are generally also difficult to place using molecular data. We predict that a dense, balanced taxon sample and protein‐encoding nuclear genes will be needed to resolve the higher‐level relationships in the Dolichopodidae.  相似文献   
8.
The present study relates to a methanol extract of the seed coat of Ginkgo biloba, and tested particularly on the third instar larvae of Spodoptera exigua. The extract was found to have an inhibitory effect on the growth of the larvae besides bringing a change in the nutrient reserves in the body of the insect. Topical application of five different doses of the methanol extract resulted in a mortal effect to third instar larvae of S. exigua that is very much dependent on the dose as well as duration of exposure. Lower doses revealed lower mortality after 24 h of application. At doses of 1.00, 2.00, 4.00, 8.00 and 16.00 ng/larva, mortalities were 9.25, 26.07, 50.32, 56.28 and 92.44%, respectively. The dose for 50% mortality (LD50) of methanol extracts by applied by a topical method with 1 µL of acetone solution was 1.92 ng/larva. Nutrient reserves like protein, glycogen and lipid are known to regulate pupation and adult emergence. These reserves have been found to be lower in treated larvae, indicating the insecticidal role of methanol extracts from G. biloba against third instar larvae of S. exigua.  相似文献   
9.
Four species of the family Polycentropodidae –Plectrocnemia baculifera, P. kusnezovi, Paranyctiophylax hjangsanchonus and Polyplectropunocturnus– are recorded from Korea. Polyplectropus nocturnus is newly recorded from the Korean peninsula. The other three species are recorded from the Republic of Korea for the first time.  相似文献   
10.
The effect of Hg treatment on hemolymph and tissue ferritin in the wax moth Galleria mellonella was examined by western blotting. At 48 h after feeding HgCl2, the level of hemolymph ferritin increased approximately 1.8‐fold over that of control insects that were not fed HgCl2, while there was a small increase in tissue ferritin. Time series experiments showed that tissue ferritin had a typically saturated pattern, with a maximum level from 24 to 72 h, although it decreased 12 h following HgCl2 feeding, while hemolymph ferritin first decreased but subsequently increased. Tissue ferritin in the fat body, gut and Malpighian tubules, the main tissues of ferritin expression, was upregulated over time following treatment with Hg, and in particular, tissue ferritin in the gut increased by a large amount at 12–48 h. The results suggest that in G. mellonella, the ferritin‐inducible mechanisms following treatment with HgCl2 are different for hemolymph and tissue ferritin, as are their biochemical properties.  相似文献   
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