A new species of cyst nematode, Cactodera chenopodiae n. sp., parasitizing common lambsquarter, Chenopodium album L., is described from native vegetation in Liaoning, China. Cactodera chenopodiae n. sp. has a circumfenestrate pattern typical of the genus and is morphologically similar to C. cacti Krall & Krall, 1978. However, in the new species, females and cysts show a larger L/W ratio whereas second-stage juveniles (J2s) have a longer hyaline region. The new species is also morphologically similar to C. milleri Graney & Bird, 1990, but the J2s differ by a larger b ratio and longer tail. Based on DNA sequences of the 28S and ITS rRNA, C. chenopodiae n. sp. comes close to C. estonica Krall & Krall, 1978, although it is distinct from the latter with respect to the presence of a punctate eggshell and larger b ratio in the J2s. Although morphometric comparisons with additional Cactodera species show the overlapping of diagnostic morphological characters, our phylogenetic analyses based on both rRNA genes support C. chenopodiae n. sp. as a unique lineage.

为了明确我国大豆主产区大豆胞囊线虫群体的发生分布及致病性分化情况,同时也为我国大豆胞囊线虫防治及抗病育种工作提供依据,本研究在全国范围内开展大豆胞囊线虫种群监测工作,对2012-2014年国家大豆产业体系的29个大豆试验站所辖150个示范县进行大豆胞囊线虫的种群密度检测,并在国际统一的鉴别寄主上进行生理小种鉴定。明确了大豆胞囊线虫在我国20个省（市/自治区）发生分布,总检出率达69.4%。并对其中11个群体进行生理小种鉴定,共鉴定出生理小种5个,即1、2、3、4和14号生理小种。其中安徽宿州、甘肃镇原、内蒙古赤峰、陕西延安和宁夏银川的鉴定此前未见报道。2012-2014年我国大豆胞囊线虫病害的发生比较严重,平均胞囊量高达99个·L -1 ,我国大豆胞囊线虫致病性分化并无明显变化,鉴定结果中1、3和4号生理小种出现频率较高,为72.7%。

采用国际通用的鉴别寄主法,鉴定连作条件下大庆和安达大豆胞囊线虫天然育种病圃生理小种和HG毒力类型.结果表明:生产条件下安达地区大豆胞囊线虫优势小种为毒力较强的14号生理小种,大庆地区为3号生理小种.室内盆栽鉴定安达试验基地HG类型为1.3.4.7,大庆试验基地HG类型为7.由于大豆胞囊线虫生理小种和毒力类型的组成日趋多样性,迫切需要发掘新的抗源和加紧培育水平抗性品种.

【Objective】The objective of this study is to research into the early stage root gene expression profile of G.max induced by H.glycines and to explore the resistant mechanism to the pathogen at molecular level.【Method】SSH-cDNA libraries enriched with differentially expressed ESTs were constructed from SCN-challenged root tissues at pre-penetration and early infection stages from Xiaoli black bean(G.max) by suppression subtractive hybridization and reverse Northern blot.【Result】 One hundred and sixty-six unique ESTs were identified and analyzed with Blastx and Blastn by comparing sequences in the GenBank.One hundred and ninteen unigenes accounted for 83% of all the unigenes showed high homology with the function known genes or proteins.The function-known ESTs were annotated into functional categories including signal recognition and transduction,energy and material metabolism,stress responses,transcriptional regulation,protein synthesis and/or modification,transport functions,cellular architecture.【Conclusion】Discreet gene tag clusters primarily including catalase,ubiquitin,chitinase,lipoxygenase,aquaporin,ripening related protein,metallothionein,plasma membrane intrinsic protein,cytochrome P450,glyceraldehyde-3-phosphate dehydrogenase were abundant in the SCN-infected roots.It is speculated that those genes played an important function in the incompatible interaction between Xiaoli black bean and H.glycines.

Hsp90 had been identified to be highly conserved among different species.The Sl-hsp90 gene of tomato was amplified from Solanum lycopersicum L-402 cultivar genome DNA by DNA-PCR method.The plant expression vector pCAMBIA1302 containing Sl-hsp90 gene was constructed.Meanwhile,we quantitatively investigated the changes in the total mRNA levels of Hsp90 in tomato roots treated with Meloidogyne incognita.Expression levels of Sl-hsp90 were examined by fluorescent real-time PCR.The stability of mRNA was estimated.It was found that Hsp90 was more inducible after nematode infected.In addition,females and second-stage juveniles(J2) of M.incognita were exposed at 4℃ and 35℃ for different times in order to explore the impact of adverse temperature on Mi-hsp90 gene expression.Expression levels of Mi-hsp90 on 35℃ in females and J2 were more than that of Mi-hsp90 at 4℃.At 35℃ a burst of expression for Mi-hsp90 was observed in J2 after 2h of heat shock treatment,then expression dropped,although remaining still relatively high after 24h.Female and J2 are more suitable for high temperature.We established the Hsp90 high expression in nematode stressed by temperature and tomato roots infected by root knot nematode.