蕹菜有机水培试验

采用水培方法,研究发酵油菜籽油粕原液稀释成4种浓度的油粕营养液对蕹莱生长发育的影响。试验结果表明,10％油菜籽油粕原液除地下部鲜质量、干质量两项指标稍低外,蕹菜的地上部鲜质量和干质量、最大枝长、最大叶面积、总叶绿素含量均为最大,且可食部分产量最高。由此可见,10％油粕营养液浓度是一种比较适宜有机水培蕹菜的菜籽油粕原液稀释浓度。     

不同播种期对水培生菜产量和品质的影响

以生菜品种绿领和弘农为材料,研究了春季不同播种期对水培生菜生长发育、产量和品质的影响。结果表明,不同播种期下生菜的产量和品质有显著差异,早播和晚播均降低生菜的产量和品质,播期为3月17日时产量最高,绿领和弘农分别为271.19 g/株和243.67 g/株;此播期的2个生菜品种VC含量也最高,且硝酸盐含量相对较低,表明选择适宜的播种期有助于提高生菜的产量和品质。     

Dissemination of Phytophthora cactorum, cause of crown rot in strawberry,in open and closed soilless growing systems and the potential for control using slow sand filtration

Closed (recirculating) growing systems provide a greater potential for the dispersal of water-borne plant pathogens and disease expression compared to open (run-to-waste) systems. Here we studied the effects of three soilless growing systems (open, closed, and closed with slow sand filtration) on the dispersion of Phytophthora cactorum propagules and the severity of the crown rot disease in strawberry (Fragaria × ananassa Duch.). The plant-growth medium used was coir fiber. The three growing systems showed the same density of P. cactorum propagules in the water drained from the growing media. However, propagules of this pathogen were not detected by the baits in the filtered solution recovered from slow sand filtration. In all systems Phytophthora propagules dispersed from the inoculated plant to adjacent uninoculated plants. At the end of the first crop no differences in the severity of crown rot were found between the different systems of crop culture. However, at the end of the second crop cycle, crown rot in the closed soilless system without slow sand filtration was more severe than in the other two systems. These results demonstrated that the commercial potential of slow sand filtration to prevent propagule dispersal and hence suppress crown rot in strawberry crops grown in a closed culture system.     

吉林地区香椿水培生产研究

［目的］为把高档蔬菜香椿引入吉林地区提供科学依据。［方法］以清水为对照,用3种传统培养液,即凡尔赛营养液、道格拉斯的孟加拉Ⅲ营养液、波司特营养液作为基本营养液,各自添加不同的微量生长激素对香椿进行水培试验。［结果］3种配方的水培营养液均适合对香椿进行水培,但其中以道格拉斯的孟加拉Ⅲ营养液添加IBA0.5mg/L为最好,在水培的各个生长阶段都表现优良,水培到25d平均高度和侧枝的长度最大,单株平均重268g。而采用凡尔赛基本营养液＋IAA0.5mg/L和波司特基本营养液＋NAA0.5mg/L作为水培营养液配方的单株平均重分别为248、250g。［结论］建议在生产香椿水培苗的过程中采用道格拉斯的孟加拉Ⅲ基本营养液＋IBA0.5mg/L作为水培营养液配方。     

A century of Nordic barley breeding—Effects on early vigour root and shoot growth, straw length, harvest index and grain weight

In cereals early vigour has been identified as an important trait affecting drought tolerance, nutrient uptake, weed competitive ability and yield. To further study how this trait has changed following years of barley (Hordeum vulgare L.) breeding for improved yield, landraces and cultivars from Sweden and Denmark were analysed for seedling root and shoot growth in hydroponics. The Swedish and Danish materials, 35 and 39 cultivars, respectively, represented the gene pool used during one hundred years of barley breeding. Besides seedling growth characteristics, straw length, harvest index and 1000-grain weight were studied in field trials over two years in Sweden, Norway and Latvia. From 1890 to 2005 straw length has decreased from 110 cm to 60–70 cm and harvest index has improved from 0.42 to 0.55, with highly significant linear relationships with year of introduction (r = −0.87 and r = 0.89, p < 0.001, for straw length and HI, respectively). Other traits like 1000-grain weight, heading and maturity date have been less affected. Seedling root weight has also decreased by 33.9 and 25% in Swedish and Danish germplasms, respectively. The decrease in shoot weight is similar to that of the root biomass. Seedling root length (longest seminal root) has decreased by about 10%, while specific root length (mm root mg⁻¹ root dry matter) has increased by 28.6 and 19.0% in Swedish and Danish cultivars, respectively, indicating the development of finer roots in modern cultivars. There are indications that during recent years the deceasing trends have been broken by the introduction of new high yielding cultivars with improved seedling growth. In line with this there are also significant positive relationships between both seminal root length (r = 0.60–0.84, p < 0.05–0.001) and root weight (r = 0.62–0.78, p < 0.05–0.001) and grain yield from official variety trials carried out in Sweden in 1995–1999 and in Sweden and Denmark in 1999–2005. Reasons for the previously decreasing trends and the new trend in modern cultivars are discussed as well as the possibility of using hydroponics for selection.     

线辣椒根系分泌物中几种化感物质对其种子萌发和幼苗生长的影响

为了探究线辣椒连作障碍的机理，通过线辣椒种子萌发和苗期水培试验，研究线辣椒根系分泌物中的6种化感物质［邻苯二甲酸二异丁酯、雪松醇、丙炔酸、2,4-双(1,1 二甲基乙基)-苯酚、二苯并呋喃、芴，其中后3种物质没有进行水培试验］对其自身种子萌发和幼苗生长发育的影响。结果表明：这6种化感物质对线辣椒种子萌发（包括发芽率、发芽势、发芽指数、胚芽长、胚根长、苗鲜质量）和苗期生长（包括株高、茎粗、根系活力、抗氧化酶活性、丙二醛含量、培养液电导率）总体表现为低浓度（0.001 mol/L以下）无影响或有促进作用，其中雪松醇的促进作用相对明显；高浓度（0.002 mol/L以上）则具有抑制作用。综合判断，丙炔酸的抑制作用最强，邻苯二甲酸二异丁酯、2,4-双(1,1 二甲基乙基)-苯酚、二苯并呋喃、芴这4种物质的抑制作用相当，程度居中，雪松醇的抑制作用最小。     

低磷胁迫下甘蓝型油菜幼苗根系差异蛋白双向电泳图谱分析

利用优化的水培体系对油菜品种中油杂9号进行缺磷和足磷幼苗根系差异蛋白表达研究，采用自制管状胶双向电泳体系技术分析幼苗根系差异蛋白，揭示油菜耐低磷胁迫的分子机制。双向电泳获得的图谱经PDQuest8.0.1软件分析表明，未处理和缺磷处理12 d的油菜根蛋白表达图谱之间的相关系数为0.720 22；根系中差异显著的蛋白质点有 62 个,稳定上调表达的蛋白点为25个，下调表达的为37个。缺磷条件下，油菜根系蛋白表达量的差异表明，在逆境中油菜可以通过调节多种蛋白的表达来适应外界环境中磷水平的变化。