不同色彩棉花抗旱性鉴定指标及评价

以抗旱性不同的白棉、棕棉和绿棉品种(品系)为试验材料,应用多元统计分析的理论与方法,研究了不同水分亏缺灌溉条件下花铃期棉花生理生化指标与抗旱性的关系.结果表明:棕色棉BC05-07-18-2抗旱性最强,绿色棉G3-6抗旱性最弱,叶片相对含水量和类胡萝卜素含量可作为棉花抗旱鉴定的重要指标,叶绿素含量和可溶性糖含量可作为参考指标.棉花品种的抗旱系数与叶片相对含水量和可溶性蛋白含量存在线性回归关系,与细胞膜透性呈显著负相关.     

黄瓜‘浙秀1号’种子纯度的SSR鉴定

种子纯度在种子生产中的重要性日益提升,分子标记技术因其具有高效、稳定、可靠等优点越来越多地被应用到种子纯度鉴定中。本研究利用SSR分子标记技术对黄瓜杂交品系‘浙秀1号’及其两亲本之间的多态性进行了引物筛选和种子纯度鉴定研究。结果表明,在699对供选SSR引物中,有3对引物分别在‘浙秀1号’杂交种和其双亲之间表现为稳定的共显性,杂交种带型为双亲的互补带型,适合于杂交种纯度鉴定。经田间试验验证,引物稳定性良好,且与田间鉴定结果非常接近,可用于‘浙秀1号’杂交种种子纯度的鉴定,显示出SSR标记技术在黄瓜杂交种子纯度的室内快速检测中有广泛应用前景。     

一些重要作物拟茎点霉属病原生物学及致病机制研究概况

拟茎点霉属(Phomopsis)是腔孢纲球壳孢科真菌中的一个大属,含有100多个不同的种,可寄生于70多种不同科的植物。该属病原菌地域分布广泛,引起植物的叶枯、枝枯、烂茎、溃疡及果腐等严重病害,造成重大的经济损失。综述了一些主要作物的拟茎点霉属真菌病害在发生特点、致病症状及特性、生活周期循环、病害生化防控及病菌生物学特性等方面的研究进展,并展望了其今后研究热点及发展趋势,认为今后应加强从组织细胞学和分子生物学方面明确其致病机制,鉴定该属的致病特异性,并构建抗病分子育种技术体系等为病害安全、高效防控提供基因基础。     

地衣芽孢杆菌抗菌肽的纯化及抗菌特性分析

从地衣芽孢杆菌（Bacillus licheniformis）LY12发酵液中分离纯化抗菌肽,并得到抗菌肽抗菌特性。通过超滤、(DEAE-Sepharose FF离子交换层析、Sephadex G-15分子筛凝胶过滤层析、反向高效液相色谱（RT-HPLC）等方法纯化该抗菌肽。LC-ESI-MS质谱显示抗菌肽分子量为2750.785Da,同Tricine SDS-PAGE分析结果基本一致。体外抗菌试验结果显示,抗菌肽LYF12能够抑制丝状真菌、细菌的生长。对枯草芽孢杆菌（Bacillus subtilis）、大肠杆菌（Escherichia coli）、铜绿假单胞菌（Pseudomonas aeruginosa）、金黄色葡萄球菌（Staphylococcus aureus）、藤黄微球菌（Micrococcus aureus）、蜡状芽孢杆菌（Bacillus cereus）、副溶血性弧菌（Vibrio parachaemolyticus）的最低抑菌浓度分别为9.8、19.8、20.7、7.2、9.6、10.2 和15.7μg/ml。抗菌肽显示出对革兰氏阴性细菌、革兰氏阳性细菌及真菌具有较好的抗菌效果。从地衣芽孢杆菌LY12分离的抗菌肽在食品防腐中具有潜在的应用价值。     

油棕园间套种菠萝对土壤养分及酶活性的影响

为了探索幼龄油棕园间套种菠萝对土壤养分以及酶活性的影响,采用大田试验,在油棕与不同品种菠萝间套种种植模式下比较分析油棕园土壤养分及土壤酶活性大小。结果表明：间套种菠萝能够降低土壤pH值,有机质含量间套种处理与对照差异不明显,菠萝收获期较生长期有机质含量提高。土壤碱解氮、有效磷含量间套种处理要高于对照,土壤速效钾生长期间套种处理高于对照,成熟期处理与对照间差异不显著。间套种处理整体上降低土壤脲酶和酸性磷酸酶的活性,但却提高了过氧化氢酶的活性。     

储藏物冷却机在高温高湿区高大平房仓的应用

选用功率较小的储藏物冷却机与负压通风相结合,对福建漳州地区的粮面压盖稻谷仓进行降温冷却,通过改变粮面压盖方式实现冷却的均匀性和彻底性.累计运行时间112.7 h,降温3.3℃,水分变化为0.1％,达到了保水降温的效果.运行期间的降温单位能耗为0.47 kW·h/℃·t,符合《谷物冷却机低温储粮技术规程》的规定,结束降温后粮面压盖延缓了粮温复温.     

Cotton Chemical Topping by Applying DPC in Different Cotton-Growing Regions

[Objective] The objective of this study was to investigate the stability and universality of cotton chemical topping by applying mepiquat chloride (1,1-dimethyl-piperidinium chloride, DPC) in different cotton-growing regions. [Method] Field experiments were conducted in 2018 at 10 locations in the Yellow River basin (Hejian and Handan, Hebei province; Dezhou and Wudi, Shandong province), the Yangtze River basin (Dafeng, Jiangsu province; Huanggang, Hubei province), and Xinjiang area (Shihezi location I and loacation II, northern Xinjiang and Luntai and Shaya, southern Xinjiang). Local cultivars/lines were used, and the experiments were performed using a randomized complete block design with three or four replicates. Accompanied with typical DPC multi-application in each location, chemical topping was conducted at 10 days before manual topping (T1) or at the same time with manual topping (T2) by applying four dosages of DPC (0, 90, 180, 270 g·hm^－2), manual topping was used as the first control and non-topping as the second control. [Result] The time of chemical topping significantly affected cotton plant height (except for the results in Handan, Dezhou and Wudi) and the number of fruit branches (except for the results in Dafeng and Huanggang). It was observed that earlier chemical topping would result in lower cotton plant height and a fewer fruit branches. In Hejian and Shihezi location I, the average plant height across DPC chemical topping at T1 stage was not only lower than that of T2 stage but also 3.3 cm and 4.6 cm lower than that of manual topping, respectively. In most locations, chemical topping at T1 stage increased around two fruit branches per plant compared with manual topping, while in T2 stage the increased fruit branches per plant ranged from 2.3 to 7.7. Also, we found that a higher dosage of DPC resulted in shorter plant height (except for that in Huanggang). In some locations, plant heights of chemical topping with 180 g·hm^－2 or 270 g·hm^－2 DPC were even shorter than that of manual topping. The number of fruit branches per plant of 0 g·hm^－2 DPC increased by 2.4-8.3 compared with manual topping. However, chemical topping with 90-270 g·hm^－2 DPC significantly reduced the number of fruit branches compared with 0 g·hm^－2 DPC. There were no significant differences in the number of fruit branches among three DPC dosages (90, 180, and 270 g·hm^－2). In Handan, seed cotton yield of chemical topping at T2 stage was significantly lower than that of manual topping due to the decreased boll number, which is possibly associated with the high temperature and drought weather after chemical topping. While at other locations, most treatments of chemical topping by using DPC did not produce significant effects on yield. In addition, chemical topping by using DPC did not delay cotton maturity, characterized by their similar boll-opening rate and the first harvest rate to those of manual topping before spraying harvest aids. [Conclusion] Cotton chemical topping with DPC is more stable and universal across different cotton-growing regions. We suggest that 90-180 g·hm^－2 DPC could be used at the same time with manual topping for cotton chemical topping.     

海南海花岛软基处理工程中真空预压法的改进与机理分析

疏浚淤泥这种超软土地基目前主要采用排水固结法进行加固,然而,工程实践发现,淤堵是一个重要的问题,新型防淤堵材料和施工工艺是研究的热点。依托恒大海南海花岛真空预压处理工程,引入一种应用于超软土地基处理的新型防淤堵真空预压法。该方法是直排式真空预压方法的进一步改进,将防淤堵排水板取代传统排水板,在连接方式上,将无孔钢丝软管取代了水平波纹管,也将传统的包扎捆绑改进成了三通密封接头,枪钉固定。结合施工动态监测和加固后检测,表明了该方法的加固效果和实用性。在此基础上,结合已有的室内模型试验研究,阐述其抽真空过程中在排水板附近防淤堵的原理和改善机制。     

平房仓横向通风技术在玉米储藏上的应用研究

为了研究平房仓横向通风技术在玉米储藏上的应用效果,明确玉米储藏过程横向通风工艺及其参数,利用高大平房仓中设计安装的横向通风设施,以及在储藏玉米粮堆中预埋的插入式毕托管,对高大平房仓横向通风系统进行实仓测试。全面开展了玉米储藏过程中横向通风工艺应用研究,测试了在横向通风系统通风时,风速、风量、系统各部分阻力和粮堆压力分布。研究发现,在储藏玉米的高大平房仓中应用横向通风系统时,粮堆单位粮层阻力较小,在实用单位通风量时,横向通风系统总阻力不大于1200Pa;同时横向通风还具有风量分配均匀、粮堆通风均匀性良好的特点。该研究为玉米在配备横向通风系统的高大平房仓储藏提供了技术支持。     

菜籽油实罐储存品质变化规律研究

通过对2010~2014年大、中、小不同罐容实罐储存的四级菜籽油,采取定点、定罐、定层、定期跟踪观察油罐"三温"变化并取样检测,发现罐温、油温均随着气温的变化而变化,其中罐温最高,油温从上至下依次降低。菜籽油的水分及挥发物、色泽、气味、滋味、加热试验(280℃)等指标在储藏期间变化均较平稳,酸值和过氧化值均呈不断上升趋势,且不同年限的菜籽油其过氧化值上升幅度明显高于酸值。油罐容量越大,满罐存储时其存油品质的稳定性越好。罐内上、中、下层酸值变化差异不明显,上层和底层的过氧化值明显高于中层。严格控制好入罐油品质量,菜籽油储藏4~5年后酸值、过氧化值等质量指标仍可保持在国家限量标准以内。