大葱生产用种量试验研究

经过2000～2001年两年试验,育苗面积66.7m2,每定植667m2大葱生产田,用种100g育出的葱苗数量少,满足不了定植需求;用种150～250g育出的葱苗质量高,数量充足,生产出的鲜葱质量和产量较高,是适宜用种量范围;用种300～450g育出的葱苗质量不高,达到壮苗标准的葱苗较少,种子浪费较多,生产出的鲜葱质量和产量较低,不宜提倡.     

Soil steaming to reduce intrarow weed seedling emergence

Steaming the soil prior to crop establishment can be a very effective method of preventing weed seedling emergence on raised beds of vegetable crops. However, current mobile steaming technology for outdoor vegetables is characterized by an extremely high energy consumption and a low work rate. This has led to the concept of band-steaming, where only a limited soil volume is steamed corresponding to the intrarow area of a row-grown vegetable crop. Weeds growing in the intrarow area are difficult to remove by traditional non-chemical means, usually involving substantial input of manual labour in organic cropping. This paper presents the initial results from laboratory studies with steaming a limited soil volume simulating a band. The investigations describe the relationship between maximum soil temperature achieved from soil steaming for different periods and effects seen on subsequent weed seedling emergence. The relationships obtained were generally sigmoid and could appropriately be described by a common dose–response function. Seedling emergence from natural weed species was reduced by 90% when the maximum soil temperature reached 61°C, and a further 10°C rise in temperature gave 99% reduction. Added and non-imbibed seeds of Lolium perenne and Brassica napus generally required higher temperatures to achieve the same control level as the natural weeds in the soil samples.     

洋葱的贮藏原理及方法

洋葱是一种无呼吸跃变的蔬菜,具有明显的休眠期。洋葱的贮藏原理就是人为地抑制其呼吸强度,延长其休眠期。为此,根据洋葱的贮藏原理和贮藏环境因素,研究了目前国内主要采用的几种洋葱贮藏方法的特点,为洋葱的贮藏与加工提供一定的参考。     

韭菜、大葱、洋葱种子芽期过氧化物酶同工酶的研究

本试验采用聚丙烯酰胺凝胶电泳技术,分析了韭菜、大葱、洋葱10个品种的种子芽期过氧化物酶同工酶的酶谱,迁移率及同工酶酶谱光密度。研究结果表明:韭菜、大葱、洋葱之间,种子芽期过氧化物酶同工酶酶谱有明显的差异。韭菜的酶带数为7条,大葱为8条,洋葱为7条,各自酶带的迁移率有很大差异,完全可以从酶带数和酶带迁移率准确鉴别这3种蔬菜作物的种子。     

Effect of Placement and Dose of Phosphatic Fertilizers on Onion

ABSTRACT

An experiment was conducted with six doses of phosphorus (P) and three placements to judge their effects on yield under gangetic alluvial soil. Univariate analysis of variance revealed that 60 kg ha^?1 P in combination with placement at 5 cm are the best with respect to different vegetative ant yield characters. Correlation and path analysis revealed that yield has got significant negative correlation with leaf dry weight. A direct negative effect of fresh weights of leaves was also evident from the path coefficient analysis. Multivariate cluster analysis following complete linkage using Euclidean distance by forming dendrogram could identify four clusters taking all the characters together. The treatment combinations T5 (2.5 cm, 60 kg ha^?1), T11 (5.0 cm, 60 kg ha^?1), T17 (7.5 cm, 60 kg ha^?1) along with T10 (5.0 cm, 45 kg ha^?1) are found to be the best lot of treatments for growth and yield of onion.     

洋葱高频离体再生体系的建立

 以洋葱（Allium cepa L.）品种‘W465’的幼嫩花序和不同发育时期的幼蕾为外植体材料,研究激素配比对其愈伤组织诱导、再生和生根驯化的影响,以建立洋葱高频离体再生体系。研究结果表明,洋葱幼嫩花序为最佳外植体材料,在含有1.0 mg · L^-1 2,4-D + 1.0 mg · L^-1 6-BA 的B5 培养基上愈伤诱导率为100%,在添加1.0 mg · L^-1 TDZ 的B5 培养基上再生芽分化率为78.13%,在1/2 MS + 0.01 mg · L^-1 NAA 培养基上可诱导生根,驯化移栽成活率达到95%。     

磷钾素处理对红葱生长和品质的影响

以1/2 Hoagland完全营养液配方为基本配方,研究了不同磷钾水平对红葱生长和品质的影响。结果表明：在相同磷浓度下,随着钾浓度升高,红葱单丛质量、单丛叶片数逐渐增加,单丛分蘖数、株高、假茎长和假茎粗有增大趋势|食用部分可溶性糖含量逐渐升高,叶片丙酮酸和大蒜素含量降低。磷浓度为0.25 mmol·L-1时,随着钾浓度升高,红葱食用部分VC含量逐渐增加,硝酸盐含量和可溶性蛋白含量均先增加后降低。P0.125K1.5处理红葱叶片和假茎总酚及总黄酮含量最高。     

西昌白皮洋葱品种春播秋收栽培试验

在3个不同的播期对中日照白皮洋葱品种12C1进行栽培对比试验.试验结果表明,中日照白皮洋葱品种12C1适宜在西昌春播秋收,最适播种期为1月19日,最适收获期为8月14日.     

激光诱变对黄皮洋葱须根的生物学效应研究

[目的]对激光诱变黄皮洋葱须根的生物学效应进行研究。[方法]采用CO2激光和He-Ne激光对黄皮洋葱2个品种的湿种子进行辐射,通过随机区组设计,利用生物统计学和生理生化的方法,从个体及生化水平上考查激光诱变黄皮洋葱L1代须根的生物学效应。[结果]经激光诱变处理的黄皮洋葱在须根长度、数目、须根重以及根系活力等方面,表现为不同处理引起的生物学效应差异显著,其中,激光种类不同引起须根长度的变异达到5%显著差异;洋葱品种不同,激光辐照引起的须根变异明显,但各处理间差异均未达到5%显著水平;激光剂量不同,引起须根数的变异达5%显著水平;激光辐射对洋葱根系活力表现为刺激效应。[结论]该研究结果为激光诱变黄皮洋葱育种提供了参考依据。     

分蘖洋葱ISSR-PCR扩增体系的建立

以分蘖洋葱幼嫩叶片DNA为试材,采用单因素试验,对ISSR-PCR扩增体系中的退火温度、模板DNA量、Mg2+浓度、dNTP浓度、Taq酶含量以及引物浓度等各因素进行优化.结果表明,在反应体系为25μL反应液中,包含DNA模板40 ng(2μL),10×PCR Buffer 3μL,Mg2+(2.5 mmol·L-1)2μL,dNTPs(2.5 mmol·L-1)3μL,引物(5 mmol·L-1)3μL,Taq酶(5 U·μL-1)0.4μL,退火温度为56℃时,分蘖洋葱ISSR-PCR扩增获得最佳效果,初步建立分蘖洋葱叶片最佳ISSR-PCR扩增体系,为ISSR分子标记技术应用于分蘖洋葱种群遗传多样性分析、遗传图谱构建、核心种质资源保存利用等奠定分子生物学的理论基础和技术支撑.