凯特杏设施栽培特性研究

对凯特杏设施栽培特性研究表明:凯特杏的光饱和点和CO2饱和点较低,耐弱光和低浓度CO2环境的能力强;它的开花需冷量较低,雌蕊败育率低,自花结实率高,丰产、稳产性强;在设施栽培条件下凯特杏果实特征发育充分表达,单果重显著增大,果实的产量和品质明显提高。凯特杏在设施栽培条件下的优势表现达,说明其适宜于设施栽培。     

可追溯茶叶产品的认知、信任与购买意愿研究

基于646份消费者调查数据,通过结构方程模型,分析消费者对可追溯茶叶产品的认知情况、信任程度与其购买意愿间的关系.研究发现,对可追溯茶叶产品认知程度的增加会提升消费者对可追溯茶叶产品的信任程度,对可追溯茶叶产品信任程度的增加会显著提升消费者购买可追溯茶叶产品的意愿;认知程度对提升消费者对可追溯茶叶产品的购买意愿有正向影...     

3SFBQ-500型果园气爆松土注肥机的优化设计与试验

针对目前果园开沟施肥存在的易伤树木根系、耕作能耗大、施肥不均等问题,该文研制了3SFBQ-500型果园气爆松土注肥机,采用液力辅助气铲激振的钻杆结构,建立液力辅助气铲钻土的力学模型及运动学方程,分析了钻杆的土力学关系,优化了钻头构型参数,优化后的钻头锥角60°、钻杆圆柱半径12.5 mm;设计了一种基于PLC控制的经济型多旋钮式开关操控系统,实现了机具手动、自动控制作业,一键操作可完成钻杆钻土、气爆松土、液肥注射、钻杆回升四步操作;在SolidWorks软件中建立了样机模型,并完成了样机的试制与田间试验工作。样机田间试验结果表明,气爆作用可在土体内部产生裂隙并扩散,300 mm钻深、0.8 MPa气爆压力下的土体最大裂隙宽约3~4 mm,裂隙扩展扰动半径约400 mm;土壤在气爆下发生扰动,扰动系数达50.11%;液肥在注肥机构作用下可在深土层中无堵塞喷射,并均匀扩散;样机操作简便,运行稳定,工作效率至少0.048 hm~2/h,满足果园施液肥农艺要求,适用于果树、园林、绿化地的施肥作业。     

峡江水利枢纽鱼道过鱼效果的初步研究

为了解峡江水利枢纽鱼道过鱼效果,采用张网法和截堵法,于2019年10月、2020年1月、2020年4月、2020年8月对峡江水利枢纽鱼道的过鱼效果开展季度调查.鱼道内共采集鱼类4605尾,计42种,隶属于4目、9科、34属,以中小型鱼类为主,体长范围为2.3～48.5 cm,优势种为宽鳍鱲(Zacco platypus...     

工艺参数对大豆基木质刨花板性能的影响

大豆蛋白类胶黏剂具有绿色、环保等特点,已成功应用于胶合板生产,但在刨花板领域应用较少。采用不同热压工艺参数,以改性双组份大豆基胶黏剂制备木质刨花板;通过正交试验研究密度、热压温度、热压时间、热压压力等因素对大豆基木质刨花板性能的影响,结果表明:密度对其性能影响最为显著,热压压力次之,而热压温度和热压时间影响不显著。生产性试验表明:大豆基木质刨花板的主要物理力学性能满足GB/T 4897—2015《刨花板》标准要求,可作为基材广泛应用于家具、墙体板等领域。     

水稻稻曲病研究进展

稻曲病已成为世界水稻生产的重要病害之一。通过对国内外稻曲病的分布与为害、稻曲病菌的生物学特性和稻曲病的侵染循环等研究进行综述,并就稻曲病抗病材料的筛选、抗性基因鉴定等方面进行了详细的说明,最后,系统分析当前稻曲病研究中存在的问题,就如何进一步深入开展稻曲病相关研究进行分析和展望。     

Screening of culture conditions for pathogens of potato dry rot

Dry rot is a severe fungal disease during potato storage. Fusarium spp. is the pathogen causing severe rot of potato tubers, producing Fusarium toxins and contaminating food. The disease leads to a huge loss to China's potato industry. The present research optimized and screened the culture conditions of the major pathogens causing potato dry rot including Fusarium culmorum, Fusarium avenaceum, Fusarium sambucinum, Fusarium solani var. coeruleum, Fusarium trichothecioides, and Fusarium sporotrioides. The results showed that F. sambucinum and F. culmorum were sensitive to temperature and pH. F. sambucinum, F. trichothecioides, F. Solani var. coeruleum, and F. sporotrioides are favorable to the glucose-based culture while F. culmorum and F. avenaceum were to sucrose-based culture. Illumination stimulated the growth of F. sambucinum and F. sporotrioides but inhibited the growth of F. culmorum and F. avenaceum. It is concluded that the culture conditions are different with species of Fusarium and the understanding of the culture conditions is expected useful in research and the disease control.     

3株O3血清型鳗弧菌灭活疫苗的免疫原性和免疫保护效果

鳗弧菌(Vibrio anguillarum)O3血清型菌株是感染鱼类的重要病原菌,本文研究了3株O3血清型鳗弧菌(SMP1、SMP3和SMP4)灭活疫苗的免疫原性和免疫保护。首先在牙鲆(Paralichthys olivaceus)体内对3株鳗弧菌进行复壮;检测复壮后的菌株毒力,检测的3株鳗弧菌对蓝蔓龙(Trichogaser trichopterus)的半数致死量(LD50)分别为105.1 CFU/ml(SMP1)、104.7 CFU/ml(SMP3)和105.4 CFU/ml(SMP4);制备了3株菌的甲醛灭活疫苗,注射免疫牙鲆,免疫后第7天可检测到牙鲆的血清特异性抗体产生,免疫后第28天的血清特异性抗体效价为1:1280(SMP1)、1:640(SMP3)和1:905(SMP4),提供的免疫保护率(Relative percent survival rate,RPS)为94.4%(SMP1)、100%(SMP3)和73.7%(SMP4)。研究表明,3株致病性O3血清型鳗弧菌菌株具有良好的免疫原性,其中SMP3为最适疫苗候选株。本研究为鳗弧菌O3血清型疫苗的开发应用奠定了基础。     

秦油2号角果的生长特性

通过测定秦油２号角果长、宽的增长及其亮、籽粒重量变化。角果长度在花后１２—１５天定型，宽度在花后２１—２８天定型。当长度达到最大值时，宽度的增长速度达最大值；当宽度达最大值时，果壳的鲜重、干重及籽粒的鲜重也达最大值。秦油２号籽粒增重具有明显的优势。     

Effects of Extrusion and Starch Removal Pretreatment on Zein Proteins Extracted from Corn Gluten Meal

In this study, the structure and selected properties of zeins extracted from corn gluten meal (CGM) pretreated by extrusion and removal of starch were investigated. The structure and properties of the zeins from pretreated CGM changed significantly. Pretreatments can decrease the extraction yields of zeins and change the granule shape and size of zein aggregates. The studies indicated that extrusion and removal of starch can significantly decrease the thermal enthalpy (ΔH₁ and ΔH₂) of zein from 1.94 ± 0.20 to 0.19 ± 0.10 and from 107.20 ± 0.80 to 78.62 ± 2.30 and J/g, respectively. The SDS‐PAGE results confirmed that the molecular weight of zeins from CGM was 24,000 and 27,000, and the molecular weight of zeins did not change with the pretreatment. On the other hand, the circular dichroism spectroscopy results showed that the processing of extrusion and removal of starch can change the secondary structure content of β‐sheets and β‐turns; these results indicated that extrusion and removal of starch can significantly break the secondary structure of zeins. Furthermore, extrusion and removal of starch can change the sulfhydryl content of zeins. The obtained results provided some fundamental information that is useful for further modification of CGM to improve its functional properties and industrial applications.