Molecular characterization of chestnut plants selected for putative resistance to Phytophthora cinnamomi using SSR markers

A set of nine short sequence repeat (SSR) loci was used for the molecular characterization of 32 accessions of 15 chestnut trees selected in the field because of their putative resistance to the ink disease caused by Phytophthora spp. The goal of the present study was to determine the genetic identity of those selected European chestnut trees (Castanea sativa) or interspecific hybrids, considering that hybridization programs between European chestnut and Asiatic species (mainly Japanese chestnut, Castanea crenata) have been carried out in Galicia (Spain) since the early 20th century. The results showed that the analyzed SSR loci were useful to discriminate three Asiatic and the European species of Castanea. The joint information provided by a factorial correspondence analysis (FCA) and the presence of privative alleles allowed the putative molecular assignment of the selected plants to a certain identity. Most of them were determined as hybrids between C. crenata and C. sativa. The individuals coded C036 and C048 were assigned, with a high probability, to C. sativa due to their clustering with accessions of this species and because they had a number of privative alleles of this species. Only a few individuals could not be assigned to any particular genotype.     

甜瓜结实花初花节位QTL分析

 以WI998为母本（纯雌株、厚皮网纹甜瓜品系）,TopMark为父本（雄全同株纯合品系）,配置杂交组合,利用单粒传得到171个株系的重组自交系（F₂S₄）群体构建甜瓜SSR分子标记遗传连锁图谱。该连锁图谱包含19个连锁群,覆盖基因组长度为1 414.2 cM,标记间平均距离为10.2 cM。对结实花初花节位开展QTL分析,共检测到9个QTL,分别分布在第1、9、10、11连锁群上,各QTL的LOD值在2.89 ~ 9.42之间,4个QTL贡献率超过10%。位于第9连锁群的QTL Fp9.4贡献率最大,为18.57%（2010秋季LOD = 9.17）;位于第9连锁群的Fp9.3（2010春季8.64%,LOD = 6.44;2010秋季17.99%,LOD = 9.42）,位于第10连锁群的Fp10.1（2010春季3.59%,LOD = 2.89;2010秋季6.20%,LOD = 3.43）在两季的位置都很稳定。获得与结实花初花节位紧密连锁（< 10 cM）的8个特异标记（SSR01737、MU141991、TJ105、GCM206、SSR04910、MU173563、NR52、MU146331）,为进一步开展QTL精细定位提供参考。     

Inhibition of Ang-2 and RGS-5 expression by nanogold results in normalization of vascellum in hepatic tumor

AIM: To observe the vascular normalization effect of nanogold on hepatic tumor by inhibiting angiopoietin-2 (Ang-2), regulator of G-protein signaling-5 (RGS-5) during certain time window. METHODS: H22 cells, the hepatocellular cancer cell line, were subcutaneously injected into the right armpits of 48 BALB/c nude mice. When the size of transplanted tumor reached 3~4 mm, the mice were divided into 2 groups: 36 mice in experiment group and 12 mice in control group. The mice in experimental group underwent injection of nanogold into the tumor once a day, and the mice in control group were injected with normal saline. After continuous treatment with nanogold for 3 days, 7 days and 11 days, the mice were sacrificed, the liver tumors were taken out to measure the size and weight. The expression of Ang-1,Ang-2 and RGS-5 in the tumor was detected by the method of immunohistochemical staining. The normalizing shapes of tumor vessels and the pericytes were observed under electronic microscope. RESULTS: With nanogold treatment for 3 days, 7 days and 11 days, the positive rates of Ang-1 were 16.7％, 50.0% and 16.7%, respectively. The positive rates of Ang-2 were 33.3%, 16.7% and 41.7%, respectively. The expression of Ang-1 in experiment group was higher than that in control group, especially at the 7th day in experiment group. The expression of Ang-2 in experiment group was lower than that in control group (58.3%), especially at the 7th day in experiment group. With nanogold treatment for 3 days, 7 days and 11 days, the positive rates of RGS-5 were 33.3%, 16.7% and 50.0%, respectively. The immature pericyte coverage indexes (IMPI) were 19.6%±4.3%, 32.5%±7.9% and 41.2%±9.1% respectively. At the 7th day in experiment group, the positive rates of RGS-5 and IMPI were lower than those in other experiment groups and control group. After treated with nanogold for 7 days, the pericytes in the parietal wall of the blood vessels in the tumor showed the tendency to grow normally in morphology and were completely covered by endothelial cells. However, the pericytes in the parietal wall of the blood vessels in control group showed differences in size, impaired integrity and only a few of the pericytes covered by endothelial cells. CONCLUSION: During the time window of nangold treatment for 7 days, the chemical can normalize the blood vessels in liver cancer by inhibiting the expression of Ang-2 and RGS-5.     

Cyclosporine A inhibits intima proliferation of rat abdominal aortas injured by balloon

AIM: To observe the effect of cyclosporine A on intima hyperplasia of rat abdominal aortas injured by balloon.METHODS: Thirty-six healthy adult male SD rats were randomly divided into 3 groups: sham group (n=12), balloon-injured group (n=12) and cyclosporine A treatment group (n=12).From the 3rd day before injury to the 30th day after injury, the rats in cyclosporine A treatment group were treated with cyclosporine A at a dose of 12.5 mg/kg everyday, while the rats in sham group and balloon-injured group were fed with the same volume of water.On the 30th day after injury, the specimens were obtained from the rats.HE staining and immunohistochemistry were used to measure the expression level of calcineurin (CaN) in arterial wall.Pathological changes of the arterial wall were observed under light microscope.The expression of CaN and nuclear factor 3 of activated T-cells(NFATc3) in the abdominal aortas was detected by the technique of real-time PCR.RESULTS: Intimal hyperplasia was observed in balloon-injured rats.The neointima was not uniform in thickness on the 30th day.The thickness of the intimal layers and the ratio of the intimal to the medial layers in cyclosporine A group were obviously lower than those in balloon group(P<0.05).Immunohistochemistry revealed that calcineurin expression increased after balloon injury, but the expression of calcineurin in cyclosporine A group was obviously decreased as compared with balloon group (P<0.05).The results of real-time PCR showed that the mRNA expression of calcineurin and NFATc3 in cyclosporine A group was significantly lower than that in balloon-injured group (P<0.05).CONCLUSION: Cyclosporine A attenuates restenosis by suppressing the CaN-NFATc signaling pathway.     

Role of translationally controlled tumor protein in PRL-3-promoted metastasis of colon cancer cells

AIM: To study the role of translationally controlled tumor protein (TCTP) in the proliferation, migration and invasion of phosphatase of regenerating liver-3(PRL-3)-promoted colon cancer cells.METHODS: The vectors pAcGFP-C3 and pAcGFP-C3-PRL-3 were constructed and transfected into the colon cancer cell line LoVo.LoVo-PRL-3 cells stably expressing PRL-3 and LoVo-control cells were established. The expression levels of PRL-3 and TCTP in both cells were detected by Western blotting and real-time PCR. The specific siRNA sequence for TCTP mRNA and control-siRNA were synthesized and transfected into the LoVo-PRL-3 cells. TCTP expression at mRNA and protein levels in LoVo-PRL-3 was detected by Western blotting and real-time PCR 24 h, 48 h and 72 h after transfection. The proliferation, migration and invasion abilities of LoVo-control cells, LoVo-PRL-3 cells, TCTP-siRNA and control-siRNA cells were detected by CCK-8 assay and the method of Transwell cell culture chambers.RESULTS: The expression of TCTP at mRNA and protein levels in LoVo cells was significantly increased after PRL-3 transfection (P<0.05). TCTP mRNA was significantly inhibited 24 h, 48 h and 72 h after transfection of TCTP-siRNA (P<0.01). TCTP protein was also significantly inhibited 48 h and 72 h after transfection (P<0.01). Compared with LoVo-control cells, the proliferation, migration and invasion abilities of LoVo-PRL-3 cells were significantly enhanced (P<0.05). However, lowering the up-regulated expression of TCTP in LoVo-PRL-3 cells inhibited the proliferation, migration and invasion abilities (P<0.05). CONCLUSION: PRL-3 promotes proliferation, migration and invasion of colon cancer cells by up-regulating the TCTP expression. siRNA targeting TCTP may be an effective method for prevention and treatment of colon cancer cell metastasis.     

2011上半年食糖市场分析

对2011上半年国内外食糖生产、供求走势进行了回顾,对糖料生产成本和食糖价格走势的成因进行了剖析,并对下半年食糖供求和价格形势进行了预测。     

Genetic control of sorghum resistance to leaf anthracnose

A study was carried out to investigate the inheritance of resistance to anthracnose, caused by Colletotrichum sublineolum, in sorghum. Crosses between resistant and susceptible parents and backcrosses between F₁ plants and the susceptible parents were carried out under field conditions. The F₁ generations and the segregant populations were evaluated under artificial inoculation conditions in the greenhouse. In the F₁ generation of all crosses with the respective isolates, all of the plants presented a resistance reaction except for the F₁ plants resulting from the BR009 × SC283 cross. In the F₂ generation, the frequencies of resistant and susceptible plants conformed to the hypothesis that one gene with two alleles controls host resistance, except in one cross. Out of the eight backcrosses, six presented segregation that corresponded to the hypothesis formulated. For most crosses, resistance was dominant, and the proportions of resistant and susceptible plants in the segregant populations conformed to the frequencies expected under the hypothesis of gene‐for‐gene resistance and dominant gene action.     

广南县杉木人工林林分密度控制图的编制

为探讨杉木人工林立木密度对优势木平均高、林分单位面积蓄积量、林分平均直径等生长因子的规律,于2003~2005年在广南县14个乡镇,设置20m×30m的杉木人工林样地215块,在实测胸径和树高的基础上进行资料整理,并编制了杉木人工林林分密度控制图。经检验,其等树高线精度为97.8%,等直径线精度为98.8%。     

果内核桃举肢蛾低龄幼虫防治研究初报

核桃是山区主要经济树种之一,由于核桃举肢蛾(Atrijuglous hetaonei yang)的为害,使核桃大幅度减产、变质,甚致绝收。过去的防治目标集中在果外的各个虫态的防治,防止幼虫蛀入果内,一旦蛀入,多采取摘掉或拾毁虫果,减少了当年的收入,或者是刨树盘树上、树下多次喷药防治成虫,有条件的地区可以收到较好的效果。但是核桃多分布在山区,刨树盘难;干高冠大的树不易喷药,加上山区缺水,连续喷药不易做到。为探讨解决这一问题,1988-1991年,我们作了用高压注射机将久效磷注射到树干内,防治果内低龄幼虫的研究。     

杨树膜脂脂肪酸和磷脂的组成与抗寒性的关系

对一年生草本植物小麦、水稻、玉米等从生物膜膜脂的组成和配比的角度来探讨抗寒机理已有很多的报告,对多年生木本植物的研究还不很多。以前的研究结果大部分都支持了脂肪酸不饱和度与抗寒性的相关性,但各种植物也不尽相同,甚至有一些相反的结论。为了比较杨树耐寒品种和不耐寒品种在化学和生理特性上的差别,本研究用现代仪器分析方法测定了耐寒欧美杨(45杨)和不耐寒美洲黑杨(69杨)的膜脂总脂肪酸、磷脂组分的配比和总磷脂含量,为判别杨树无性系新品种的抗寒能力提供了依据。