研究了室内条件下信息化合物及稻飞虱卵的形态特征在稻虱缨小蜂识别2种卵寄主褐飞虱和白背飞虱中的作用。结果表明，褐飞虱和白背飞虱雌成虫诱导的水稻挥发物对稻虱缨小蜂的引诱作用显著差异，各自的引诱比例（头数）分别为57.50%（23头）和42.50%（17头）。稻虱缨小蜂对2种飞虱4组材料，完整卵、磨碎卵、带卵叶鞘和若虫为害叶鞘的行为反应，除了在褐飞虱完整卵上的搜索时间极显著地长于在白背飞虱完整卵上的以外，其余的均不存在差异。挥发物捕集结果表明，褐飞虱和白背飞虱雌成虫诱导的水稻挥发物组成相非常一致。上述结果表明水稻挥发物、稻飞虱利它素及飞虱卵的形态特征在稻虱缨小蜂识别褐飞虱和白背飞虱卵中的作用不明显。文中就稻虱缨小蜂识别2种寄主的机制进行了讨论。

利用行为生测考察了褐飞虱为害程度、水稻生育期和品种对水稻挥发物引诱褐飞虱卵期寄生蜂稻虱缨小蜂活性的影响。结果表明，雌成虫10头/株和20头/株为害1d的水稻挥发物，对稻虱缨小蜂具明显的引诱作用，而1头/株、5头/株、40头/株和80头/株为害1d的，与空白对照相比不显示明显的引诱作用。稻虱缨小蜂对TN1未处理稻株挥发物的趋性不明显，并且对不同生育期的稻株亦无明显差异；但受褐飞虱为害后，生育期60d的稻株比90d的对稻虱缨小蜂具更强的引诱作用。不同品种未处理稻株间，TN1挥发物对稻虱缨小蜂的引诱作用明显地比Nabeshi强，而其他品种间差异不显著。在受到褐飞虱为害后，品种间的差异趋于明显。汕优63比TN1具更强的引诱作用，而Nabeshi、IR26和丙97-59等品种对稻虱缨小蜂的引诱作用则明显弱于TN1。

Experiments were conducted in laboratory to study the impacts of rice genotypes and rice plants treated with different levels of nitrogen on the predation rates of the predator, Cyrtorhinus lividipennis Reuter, for eggs of the rice brown planthopper (BPH), Nilaparvata lugens (St

Allopolyploid speciation occurs instantly when the genomes of different species combine to produce self-fertile offspring and has played a central role in the evolution of higher plants, but its consequences for adaptive responses are unknown. We compare herbivore-recognition and-resistance responses of the diploid species and putative ancestral parent Nicotiana attenuata with those of the two derived allopolyploid species Nicotiana clevelandii and Nicotiana bigelovii. Manduca sexta larvae attack all three species, and in N. attenuata attack is recognized when larval oral secretions are introduced to wounds during feeding, resulting in a jasmonate burst, a systemic amplification of trypsin inhibitor accumulation, and a release of volatile organic compounds, which function as a coordinated defense response that slows caterpillar growth and increases the probability of their being attacked. Most aspects of this recognition response are retained with modifications in one allotetraploid (N. bigelovii) but lost in the other (N. clevelandii). Differences between diploid and tetraploid species were apparent in delays (maximum 1 and 0.5h, respectively) in the jasmonate burst, the elicitation of trypsin inhibitors and release of volatile organic compounds, and the constitutive levels of nicotine, trypsin inhibitors, diterpene glycosides, rutin, and caffeoylputrescine in the leaves. Resistance to M. sexta larvae attack was most strongly associated with diterpene glycosides, which were higher in the diploid than in the two allotetraploid species. Because M. sexta elicitors differentially regulate a large proportion of the N. attenuata transcriptome, we propose that these species are suited for the study of the evolution of adaptive responses requiring trans-activation mechanisms.

Although nitrogen (N) availability is known to alter constitutive resistance against herbivores, its influence on herbivoreinduced responses, including signaling pathways, transcriptional signatures, and the subsequently elicited chemical defenses is poorly understood. We used the native tobacco, Nicotiana attenuata, which germinates in the postfire environment and copes with large changes in soil N during postfire succession, to compare a suite of Manduca sexta- and elicitor-induced responses in plants grown under high- and low-N (LN) supply rates. LN supply decreased relative growth rates and biomass by 35% at 40d compared to high-N plants; furthermore, it also attenuated (by 39 and 60%) the elicitor-induced jasmonate and salicylate bursts, two N-intensive direct defenses (nicotine and trypsin proteinase inhibitors, albeit by different mechanisms), and carbon-containing nonvolatile defenses (rutin, chlorogenic acid, and diterpene glycosides), but did not affect the induced release of volatiles (cis-a-bergamotene and germacrene A), which function as indirect defenses. M. sexta and methyl jasmonateinduced transcriptional responses measured with a microarray enriched in herbivore-induced genes were also substantially reduced in plants grown under LN supply rates. In M. sexta-attacked LN plants, only 36 (45%) up-regulated and 46 (58%) down-regulated genes showed the same regulation as those in attacked high-N plants. However, transcriptional responses frequently directly countered the observed metabolic changes. Changes in a leaf's sensitivity to elicitation, an attacked leaf's waning ability to export oxylipin wound signals, and/or resource limitations in LN plants can account for the observed results, underscoring the conclusion that defense activation is a resource-intensive response.

A kairomone produced by the rice white-backed planthopper Sogatella furcifera (Horvath) for the mymarid egg parasitoid Anagrus nilaparvatae Pang et Wang was investigated. Eggs, female and male adults, nymphs, exuvia, honeydew, nymph-damaged plants and plants with S. furcifera eggs all elicited searching behavior in the parasitoid. Eggs, female adults and plants with eggs were the most attractive, while exuvia and honeydew evoked the weakest responses. The active compound(s) from S. furcifera female adults, nymphs and plants with eggs could be effectively extracted with methanol, acetone, n-hexane, ethyl ether and dichloromethane. Isolation of the active chemical(s) in three solvent extracts, the acetone and n-hexane extracts of S. furcifera female adults, and the acetone extract of S. furcifera nymphs, was accomplished by thin-layer chromatography. Only one fraction was active and had the same chemical properties in the three solvent extracts. Infra-red analysis of this fraction revealed a kind of ester with saturated and unsaturated fatty acids, which was previously found to be active in the same compound as the extracts from the nymphs and female adults of the rice brown planthopper, Nilaparvata lugens (St

植物在遭受植食性昆虫攻击时，能通过释放挥发物调节植物、植食性昆虫及其天敌三者间的相互关系，并由此而防御植食性昆虫。主要就虫害诱导的植物挥发物的基本特性、生态学功能及其释放机制进行了系统性综述，并提出了今后的研究方向。

研究了由挥发物传递的稻虱缨小蜂、黑户绿盲蝽种内种间关系。绍果表明，稻虱缨小蜂和黑户绿盲蝽通过挥发物而产生的种内作用不明显；稻虱缨小蜂并不明显避开“稻苗+飞虱雌成虫+黑肩绿盲蝽”复合体，黑肩绿盲蝽则明显地趋向“稻苗+飞虱雌成虫+稻虱缨小蜂”复合体。

以TN1为供试水稻品种，研究了稻株挥发物在褐飞虱、白背飞虱寻找寄主及调节两种飞虱种内种间关系中的作用。结果表明健康稻株挥发物对揭趁虱、白背飞虱具有明显的引诱作用。当稻株被一种飞虱为害12h后。其所释放的挥发物对另一种飞蛾有明显的引诱作用，但对同种飞虱则无显著的吸引或驱避作用。随着为害程度的加重（为害1d以上）两种飞虱均避开虫害株而趋向健康稻株。

利用Y-型嗅觉仪研究了二化螟绒茧蜂Cotesia chilonis对寄主植物（水稻或茭白）、二化螟Chilo suppressalis幼虫、虫粪及虫害苗挥发物的行为反应。健康植株、二化螟幼虫和虫粪的挥发物对二化螟绒茧蜂具有显著引诱作用。在虫害苗与健康苗挥发物之间，二化螟绒茧蜂显著地偏好虫害苗，但当去除虫害苗中的幼虫和虫粪后。寄生蜂对去虫苗与机械损伤苗的选择无显著差异；在虫害苗与有虫健康苗之间，寄生蜂显著趋向虫害苗，表明虫害苗本身释放的挥发物对二化螟绒茧蜂引诱作用与机械损伤苗无显著差异，但与二化螟幼虫或虫粪挥发物之间可能具有协同增效作用。水稻苗经机械损伤或损伤后以二化螟幼虫唾液处理，其挥发物对二化旗绒茧蜂的引诱作用无显著改变。二化螟绒茧蜂对不同为害程度水稻挥发物的选择无显著差异。二化螟绒茧蜂对两种寄主植物的健康苗、虫害苗、取食两种植物的幼虫及虫粪的挥发物的选择无显著差异结果表明二化螟绒茧蜂栖境定位和寄主选择过程中所利用的挥发物主要来自寄主植物、二化螟幼虫和虫粪以及虫害苗与幼虫和虫粪的协同作用。