The effects of Trichoderma on preventing cucumber fusarium wilt and regulating cucumber physiology

In our previous studies, we identified 3 Trichoderma strains with anti-Fusarium oxysporum activity, including T. asperellum 525, T. harzianum 610, and T. pseudokoningii 886. Here, we evaluated the effects of these 3 Trichoderma strains on preventing cucumber fusarium wilt through pot culture and greenhouse culture experiments. All 3 Trichoderma strains demonstrated higher control effects toward cucumber fusarium wilt than previous studies, with efficacies over 78%. Additionally, inoculation with the 3 Trichoderma strains significantly promoted the quality and yield of cucumbers. Among the 3 strains, Trichoderma 866 was the most effective, with disease control efficacy of 78.64% and a cucumber yield increase of 33%. Furthermore, seedlings inoculated with Trichoderma exhibited significantly increased measures of plant height, stem diameter, leaf area, aboveground fresh weight, underground fresh weight, chlorophyll content, and nitric nitrogen content, as well as the activities of several stress-resistance enzymes, including superoxide dismutase (SOD), peroxidase (POD), catalase (CAT), polyphenol oxidase (PPO), and ascorbate oxidase (AAO). In addition, the plants inoculated with Trichoderma showed decreased cell membrane permeability and malondialdehyde (MDA) content in the leaves. Together, our results suggest that T. asperellum 525, T. harzianum 610, and T. pseudokoningii 886 inoculations inhibit F. oxysporum infection, stimulate the metabolism in cucumbers, and enhance the activities of stress-resistance enzymes, which consequently promote the growth of cucumber plants, prevent cucumber fusarium wilt, and improve the yield and quality of cucumbers. T. harzianum is a commonly used biocontrol fungus, while few studies have focused on T. asperellum or T. koningense. In this study, strains of T. asperellum and T. pseudokoningii showed excellent plant disease prevention and growth promoting effects on cucumber, indicating that they also have great potential as biocontrol fungi.     

豫西褐土区施钾对芥菜品质的影响

在豫西褐土区研究了施钾对芥菜品质、硝酸还原酶(NR)、谷丙转氨酶(GPT)等活性的影响。试验结果表明，在速效钾含量为82 mg/kg的供试土壤上施用钾肥，芥菜(块根)的品质性状明显受到影响；施钾量在0~17.5 kg/667 m2时，增施钾肥对芥菜品质的改善效应增强；超过17.5 kg/667 m2时，芥菜品质趋于稳定，进一步增加钾肥对品质的影响作用减小；施钾量增加对荠菜品质的改善，与叶片的NR和GPT活性增强有关。     

Knowledge Mapping Analysis on Global Bovine Mastitis Vaccine Research

To understand the overall status and focus of bovine mastitis vaccine research,knowledge maps of mainly country,institution,author,cite journal,cite reference,keyword,year distribution of publications on research of bovine mastitis vaccine were studied by Citespace Ⅲ,which collected 4 205 international scientific literatures download from Web of Science^TM core collection (1995 to 2015).The results showed that in research field of bovine mastitis vaccine,the number of published papers increased from 1995 to 2012,but it began to decrease in 2013;Countries and institution involved in the research were mainly distributed in America,Europe and Asia,and universities played important roles in this field;In addition,the research field were mainly focus on:Isolation and identification of pathogens,detection of drug susceptibility and pathogenesis exploration;Immune response and relevant regulatory factor in infected dairy cows;Best period for prevention and treatment;Screening for candidate antigen.In future time,studies will pay more attention on research of NF-κB and biofilm in field of bovine mastitis vaccine.     

INTERFERENCE BY NON-HOST PLANT ROOTS AND ROOT EXUDATES IN THE INFECTION PROCESSES OF PHYTOPHTHORA NICOTIANAE

• The roots of non-host plant interfere infection of Phytophthora nicotianae.• Vanillin and other compounds play key roles in antimicrobial activity of fennel roots.• ROS accumulation is the potentially mechanism involved in inhibition of antimicrobial compounds on P. nicotianae.Crop rotations are widely used because they can significantly reduce the incidence of pests and diseases. The interactions between non-host roots and pathogens may be key in the inhibition of soilborne pathogens in crop rotations. Interactions between fennel (Foeniculum vulgare) roots/root exudates and Phytophthora nicotianae were investigated because of the known allelopathy between fennel and tobacco (Nicotiana tabacum). The effects of the key compounds in the fennel rhizosphere on the mycelial growth and zoospore behavior of P. nicotianae were assessed. The roots of fennel attracted P. nicotianae zoospores and inhibited their motility and the germination of cystospores, with some cystospores rupturing. 4-ethylacetophenone, vanillin and N-formylpiperidine were consistently identified in the fennel rhizosphere and were found to interfere with the infection of P. nicotianae, especially vanillin. Hyphae treated with these compounds produced more abnormal branches and accumulated reactive oxygen species. These interspecific interactions between non-host roots and pathogens were found to be an important factor in the inhibition by fennel of infection by P. nicotianae.     

桃PpCBF2基因克隆及其响应低温表达特性研究

为探讨桃品种间抗寒差异的分子基础,以野生毛桃(Prunus persica)和17个桃品种和品系为试验材料,通过PCR与RT-PCR克隆PpCBF2基因;并利用qRT-PCR分析‘早红霞’和‘大久保’叶片中PpCBF2在低温下的表达特性。结果表明:1)毛桃PpCBF2基因的DNA和cDNA全长序列均为894bp,开放阅读框为690bp,编码229个氨基酸并且含有CBF家族的AP2/EREBP功能域;2)供试的17个桃品种和品系的PpCBF2基因核苷酸序列全长和编码氨基酸数目与毛桃相同,但有9个品种发生1～2个氨基酸位点突变:其中‘白芒蟠桃’、‘81715’和‘大久保’的突变发生在N-豆蔻酰化位点或酪蛋白激酶II磷酸化位点;‘Italia 3’、‘寒露’和‘B6832’的突变发生在AP2/EREBP功能域;3)‘早红霞’和‘大久保’PpCBF2基因均被低温诱导,品种间表达水平有显著差异。综上,该基因在桃品种间进化较为保守,但少数品种基因功能位点发生了突变;该基因被低温显著诱导,与抗冷性有关。     

药食同源植物葛根的研究进展

葛根营养丰富,是一种重要的药食同源植物,可开发为多种药用和保健食品,市场前景广阔。综述了葛根资源与分布、化学成分、药用历史、食品开发与利用、育种栽培等方面的研究进展,以期为葛根的研究及开发利用提供参考。     

香梨优斑螟危害调查及其空间分布格局研究

通过全面调查4块不同立地条件下的扁桃(Amygdalus communis L.)标准地,针对香梨优斑螟(Euzo-phera pyriella Yang)在扁桃上的危害特点进行分析,并采用5种不同的判断空间分布格局的聚集度指标法和Iwao、Talor等回归分析法对香梨优斑螟的空间分布型进行了研究。结果表明,香梨优斑螟的发生程度与树龄、树体部位之间有密切关系,危害程度随树龄增大而加重,最高有虫株率达82.4%,危害部位主要集中在侧枝和主枝,以侧枝居多,最高有虫株率达54.01%。香梨优斑螟幼虫的空间分布为聚集型,并且分布的基本成分为个体群,个体间相互吸引。根据Iwao方法确定了香梨优斑螟幼虫在不同密度下的最适抽样数公式为m*=2.868 74+1.704 18m。     

两年制硕士研究生创新教育探析

分析了我国目前硕士研究生创新教育中存在的问题,指出了两年制硕士教育的改革需要指导教师,从创新意识和创新基础两方面加强对学生的指导,同时要为研究生创造适宜的创新环境,才能保证硕士研究生的教育质量。     

Laplace多尺度图像增强去噪算法

针对传统的单尺度图像增强算法的不足,提出了一种基于Laplace多尺度分解的图像增强算法。该算法将图像分为由高频到低频若干个子图像,对每个频道的细节图像进行不同的非线性变换,使得图像中最细微的、对诊断有用的信息得到有效的增强,同时图像又不被过增强,再通过分解的逆过程重建图像。试验表明,该方法能有效提高图像中细节的清晰度并抑制噪声。     

利用破产概率分析彩票中的风险问题

主要研究彩票公司发行彩票所存在的风险问题.通过引入保险中"破产"的概念,建立了彩票风险的数学模型,定义了某一期彩票破产的概率.应用一些概率方法得到了某一期彩票破产概率函数的表达式及破产概率的上、下界.指出当破产概率大于某个值的时候,彩票公司的运营就会存在危险.