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61.
Edgardo S. Jiménez-Martínez & Nilsa A. Bosque-Pérez 《Entomologia Experimentalis et Applicata》2009,133(1):19-26
The life history of the bird cherry-oat aphid, Rhopalosiphum padi (L.) (Hemiptera: Aphididae), was studied via laboratory assays on Wheat streak mosaic virus (WSMV)-infected and non-infected transgenic and non-transformed wheat [ Triticum aestivum L. (Poaceae)]. Although R. padi is not a WSMV vector, it is known to colonize WSMV-infected wheat plants. Two transgenic soft white winter wheat genotypes, 366-D03 and 366-D8, that express the WSMV coat protein gene, and the WSMV-susceptible non-transformed cultivar Daws were tested. All genotypes showed disease symptoms when infected with WSMV. Whereas plant height was significantly reduced on virus-infected compared to non-infected plants of all genotypes, virus-infected transgenic plants exhibited lower virus titer and lower disease rating scores than Daws. No significant effects of WSMV infection or genotypes were observed on the length of R. padi nymphal development period, nor on their pre-, and post-reproductive periods. Rhopalosiphum padi reproductive period was significantly longer on Daws infected with WSMV than on non-infected plants of this cultivar. In contrast, there were no significant differences in length of R. padi reproductive period between virus-infected and non-infected transgenic plants within a genotype. Rhopalosiphum padi daily fecundity was significantly lower and adult longevity significantly longer on virus-infected than on non-infected plants of all genotypes. Total aphid fecundity and intrinsic rate of increase were not significantly different among treatments. The percentage of winged aphids that developed was greater on WSMV-infected compared to non-infected plants within a genotype. Results indicate that both virus infection status of plants and wheat genotype influence the life history of R. padi. 相似文献
62.
Mostafa A. Abbassy Samir A. M. Abdelgaleil & Rasha Y. A. Rabie 《Entomologia Experimentalis et Applicata》2009,131(3):225-232
The essential oil from leaves of Majorana hortensis Moench (Lamiaceae) was isolated by hydrodistillation with a yield of 1.6% (wt/wt). The insecticidal activity of the oil was evaluated against fourth instars of Spodoptera littoralis Boisduval (Lepidoptera: Noctuidae) and adults of Aphis fabae L. (Hemiptera: Aphididae). The oil showed a remarkable toxic effect against S. littoralis in a topical application assay (LD50 = 2.48 μg per larva) and in a residual film assay (LC50 = 3.14 g/l). The oil of M. hortensis also exhibited a pronounced toxic effect against A. fabae adults with LC50 values of 1.86 and 2.27 g/l in rapid dipping and residual film assays, respectively. Gas chromatography-mass spectrometry analyses of M. hortensis essential oils revealed the presence of 31 compounds and the main components were terpinen-4-ol (30.0%), γ-terpinene (11.3%), and trans -sabinene hydrate (10.8%). Repeated column chromatography of M. hortensis oil on silica gel led to the isolation of two major constituents, which were characterized based on 1 H-nuclear magnetic resonance and mass spectrometric data, as terpinen-4-ol and γ-terpinene. These two components were examined for their insecticidal and synergistic activities towards S. littoralis and A. fabae . Terpinen-4-ol and γ-terpinene exhibited a significant insecticidal activity against both insects, but γ-terpinene was more toxic than terpinen-4-ol. When tested in a binary mixture with the synthetic insecticides profenofos and methomyl, it was found that both compounds enhanced the insecticidal activity of these insecticides by two- to threefold. These results show that terpinen-4-ol and γ-terpinene have a synergistic effect on the insecticidal activities of synthetic insecticides profenofos and methomyl. 相似文献
63.
Abstract Identification of aphid species is always difficult due to the shortage of easily distinguishable morphological characters. Aphid genus Toxoptera consists of species with similar morphology and similar to Aphis in most morphological characters except the stridulatory apparatus. DNA barcodes with 1 145 bp sequences of partial mitochondrial cytochrome‐coxidase I (COI) genes were used for accurate identification of Toxoptera. Results indicated mean intraspecific sequence divergences were 1.33%, whereas mean interspecific divergences were greater at 8.29% (0.13% and 7.79% if T. aurantii 3 and T. aurantii 4 are cryptic species). Sixteen samples were distinguished to four species correctly by COI barcodes, which implied that DNA barcoding was successful in discrimination of aphid species with similar morphology. Phylogenetic relationships among species of this genus were tested based on this portion of COI sequences. Four species of Toxoptera assembled a clade with low support in maximum‐parsimony (MP) analysis, maximum‐likelihood (ML) analysis and Bayesian phylogenetic trees, the genus Toxoptera was not monophyletic, and there were two sister groups, such as T. citricidus and T. victoriae, and two clades of T. aurantii which probably presented cryptic species in the genus. 相似文献
64.
蚜属轭蚜亚属的研究及一新种记述(同翅目:蚜科) 总被引:1,自引:1,他引:0
本文记述世界范围蚜属的轭蚜亚属11种,其中包括1新种,地肤轭蚜Aphis (Zyxaphis)kochiae Zhang et Zhang,sp.nov.。给出分种检索表。该亚属为中国新纪录。模式标本存放在中国科学院动物研究所标本馆。地肤phis(Zyxaphis)kochiae Zhang et Zhang,sp.nov.,(图1~6)正模,无翅孤雌,No.Y7701-2-其余同正模。中与A.( 相似文献
65.
张丽坤 《Entomologia Sinica》2000,(4)
依阿华蚜属仅在美国报道过 ,原为单种属。本文记述依阿华蚜属 1新种 ,张依阿华蚜Iowanazhangi ,增加了该属在中国分布的记录。文中给出分种检索表。新种的模式标本采自黑龙江省尚志县帽儿山 ,现存放在中国科学院动物研究所标本馆。新种张依阿华蚜Iowanazhangi与I .frisoni的区别为 :1)尾片三角形 (后者 :宽圆形 ) ;2 )腹管表面光滑 (后者 :有瓦纹 ) ;3)触角 6节 (后者 :5节 ) ,末节鞭部为基部的 2 .0 2倍 (后者 :1.4 3倍 ) ;4 )触角末节的原生感觉圈有副感觉圈相伴 (后者 :无 ) ;5)喙末节为后跗节II的 1.0 5倍 (后者 :1.71倍 )。该新种种名以昆虫学家张广学院士的姓氏命名。 相似文献
66.
Fitness effects of two facultative endosymbiotic bacteria on the pea aphid,Acyrthosiphon pisum,and the blue alfalfa aphid,A. kondoi 总被引:4,自引:0,他引:4
De-Qiao Chen Clytia B. Montllor Alexander H. Purcell 《Entomologia Experimentalis et Applicata》2000,95(3):315-323
The effects of two bacterial endosymbionts, designated PASS and PAR, were evaluated on the pea aphid, Acyrthosiphon pisum (Harris) (Hemiptera:Aphididae), in which they occur facultatively, and on the blue alfalfa aphid, A. kondoi Shinji, in which these bacteria have not been found in natural populations. Subclones of pea aphids and blue alfalfa aphids, derived from parent aphid clones that did not contain PASS or PAR, were infected with one or both bacteria, generating PASS- and/or PAR-positive subclones with minimal genetic differences from the parent clones. Under laboratory conditions at 20 °C, PAR consistently reduced the fecundity (by between 19 and 60%) of subclones derived from three different parent pea aphid clones on bur clover, Medicago hispida Gaertn. PAR had intermediate effects on pea aphids reared on sweet pea, Lathyrus odoratus L., and had no significant effect on pea aphids on alfalfa, Medicago sativa L. The effect of PASS was either neutral or negative, depending on parent clone as well as host plant. Also at 20 °C, PASS reduced fecundity (70–77%) and longevity (40–48%), and increased the age of first reproduction (by up to 1.5 days) of blue alfalfa aphid reared on alfalfa and clover. PAR had a less dramatic effect (e.g., 30–39% reduction in fecundity) on these traits of blue alfalfa aphid. In contrast, PAR and PASS increased the fitness of pea aphid subclones of one parent clone reared for three generations at 25 °C on each of the three test plants. Without facultative bacteria, fecundity of the parent clone was reduced to a mean total of < 6 offspring per adult at this elevated temperature, but with PASS or PAR, mean total fecundity of its subclones was > 35. However, this ameliorative effect of facultative bacteria at 25 °C was not found for two other sets of parent clones and their derived subclones. Alate production in pea aphids was significantly increased in large populations of two PASS- and PAR-positive subclones relative to their parent clones. Attempts to transmit PASS or PAR horizontally, i.e., from aphid to aphid via feeding on host plants (bur clover), were unsuccessful. 相似文献
67.
中国椴斑蚜属Tiliaphis Takahashi已知2种,朝鲜椴斑蚜Tiliaphis coreanus Quednau,1979和小椴斑蚜T.shinae(Shinji,1924)(中国新纪录)。文中提供了分种检索表,各种提供了观察标本、地理分布、寄主植物等信息新纪录种提供了详细的形态记述和形态特征图。研究标本保存在中国科学院动物研究所动物标本馆。 相似文献
68.
扁蚜亚科昆虫虫瘿多样性研究(半翅目,蚜科) 总被引:2,自引:0,他引:2
虫瘿是蚜虫诱导植物异速生长的结果,虫瘿作为蚜虫重要的延伸特征,对蚜虫系统分类、系统发育关系、以及起源演化等研究具有非常重要的作用.而且虫瘿的形态结构、着生部位等在蚜虫的物种间存在非常丰富的多样性,是蚜虫重要的生物学特征,也是物种鉴定的重要依据之一.本文在已有标本采集记录和资料的基础上,从结瘿的植物、虫瘿着生部位、形态结构及类型等4个方面对扁蚜亚科虫瘿的多样性进行了系统研究.结果表明该亚科蚜虫大多都在原生寄主上形成虫瘿,个别属及种可在次生寄主上成瘿;虫瘿在类型上有虫瘿和伪虫瘿之别;在着生部位上,有叶片、叶脉、叶柄、小枝、粗枝等;虫瘿的形状也十分多样,有管状、袋状、球状、半球形、刺球状、纺锤形、圆锥形、分支状、香蕉束状等;在结构上既有单室、多室之分,也有开放型、封闭型之别.对于虫瘿多样性的研究,可为虫瘿演化规律的探讨提供重要信息,也是基于虫瘿进行物种鉴定的重要基础. 相似文献
69.
An assessment was made of the antibiotic and antixenotic resistance of three cultivars of autumn flowering chrysanthemum (derived
fromDendranthema morifolium (Ramat) Tzvelev andD. indicum (L.) Desmoulins) to the aphidAphis gossypii Glover. Antibiosis was also assessed at the top, middle and lower leaves of the plant. The three cultivars showed a range
of resistance with Hero being the most susceptible, Surfine the most resistant and Purple Anne intermediate. There was a trend
for antibiosis to improve with position down the plant, however there were cultivar by position interactions. Antixenosis
was assessed at two levels, the first being under conditions where the aphid had complete access to the plant in caged choice
assays and the second being under conditions where the aphid only had host odour to assess under olfactometer choice conditions.
Preferences under the caged choice conditions found Hero to be the most preferred cultivar while there was no preference shown
between Purple Anne and Surfine. However, olfactometer assessments showed Hero to be the least preferred of the three cultivars
and, again, no preferences could be found between Purple Anne and Surfine. 相似文献
70.