双低三系杂交油菜蜀杂9号选育研究

蜀杂9号为四川大学生命科学学院育成的甘蓝型油菜细胞雄性不育三系中熟杂交种,参加四川省区试产量为1917．0－2256．0kg/hm^2,比对照种中油821增产33．82％,生产示范最高产量2541．0kg/hm^2。品质优良,芥酸含量0．02％,硫甙（含吲哚硫代葡萄糖甙）含量23．03μmol/g,含油量（干基）41．47％,2001年通过四川省农作物品种审定委员会审定。     

Untersuchungen zum endophytischen Befall von Fusarium proliferatum (Matsushima) Nirenberg in geernteten Stangen von Spargel (Asparagus officinalis L.)

Zusammenfassung Erstmalig wurden mit den vorliegenden Untersuchungen Spargelstangen zur Haupterntezeit auf endophytischen Pilzbefall untersucht. Sie zeigen, dass im Ernteprodukt zwar Fusarium proliferatum als potenzieller Mykotoxinbildner zu finden ist. Eine mögliche natürliche Kontamination mit Fumonisinen bestätigte sich nicht. Von den mit F. proliferatum infizierten Stangen wies nur eine Stange mit grau-rosa-orange farbenen Gewebeveränderungen an der Basis sichtbare Symptome auf. Allgemeine Rückschlüsse auf eine mögliche Gefährdung oder Nichtgefährdung des Verbrauchers beim Verzehr von mit F. proliferatum kontaminierten, symptomlosen Stangen können aus der Analyse nicht gezogen werden. Hierzu müssen weitergehende Untersuchungen zur Wirt-Pathogen-Interaktion erfolgen und die phänotypischen und genotypischen Einflussfaktoren in diesem Prozess noch näher untersucht werden.     

Light, temperature and burial depth effects on Rumex obtusifolius seed germination and emergence

Trials were carried out to investigate the effects of light and temperature on germination of Rumex obtusifolius L. After several months of storage, seeds gradually lost dormancy and became photosensitive. Thermal optima for germination were between 20 °C and 25 °C in light or in darkness. At lower temperatures there was a greater demand for light, so that the greatest differences in germination percentage (between low and high temperatures) were found within the 10–15 °C temperature range. The calculated thermal minima ( x -intercept method) in light and darkness were 8.3 °C and 6.1 °C respectively. Daily temperature fluctuation increased germination even after seed irradiation with far-red light, suggesting a lower demand for the far-red-absorbing form of phytochrome. Seed burial inhibited germination in proportion to depth; however, germination inhibition was independent of seed phytochrome photo-equilibrium, which had been diversified by seed pretreatment with light. Seedlings did not emerge when seeds were buried >8 cm deep. Recovery of ungerminated seeds showed that excessive burial did not impede seedling emergence but rather prevented seed germination. However, this induction of dormancy was lost once germination processes were activated (24–48 h at 20 °C) that made germination irreversible. Temperature was also involved in inhibition, and low temperature (<15 °C) induced the least inhibition. This is discussed in terms of processes of respiration and fermentation in buried seeds.     

Inhibitory and promotive allelopathy in rice (Oryza sativa L.)

Studies on allelopathic rice, which inhibits the germination and development of weeds such as barnyardgrass ( Echinochloa spp.) and ducksalad [ Heteranthera limosa (Sw.) Wild.], have been strongly conducted in the USA, the Philippines, Japan, Korea, and other countries since the 1980s. Weed-suppressing rice plants can compete with weeds for light and mineral nutrients by their rapid and thick growth characteristics, and probably also by their allelopathic effects. It was suggested that allelopathic properties were inherited from parents. Different screening methods for finding allelopathic rice simply and rapidly have been proposed. In contrast, stimulative allelopathy in rice, which promotes germination of the dormant and dormancy-awakened seeds of Monochoria vaginalis (Burm. f.) Kunth var. vaginalis , has been investigated by the authors since the 1990s. Rice seeds promoted the germination in the dark and in light under submerged conditions. Our experiments suggested that rice seeds, hulls, plants and straw contain stimulative substance(s) that promote seed germination of M. vaginalis .     

小菜蛾弯尾姬蜂室内批量繁殖的技术

报道小菜蛾弯尾姬蜂室内批量繁殖工艺技术。实验室温度：20℃－25℃，光照：L：D12：12，相对温度：65％－70％，40m^2温室面积用于栽培甘蓝。在此条件下，每周可生产2000头－3000头小菜蛾弯尾姬蜂，可田间释放寄生蜂防治小菜蛾15亩－20亩。     

The influence of cyst nematodes and drought on potato growth. 3. Effects on carbon isotope fractionation

A good agreement was found between drought induced water-use efficiencies and carbon isotope fractionation of potato plants of the same age. Discrimination of¹³Carbon isotope increased with plant age and with the rank order of the distinguished plant organs. In young plants, nematode infection (contrary to drought) reduced¹³C discrimination but also reduced the water-use efficiency, leading to the conclusion that nematode infection, by slowing down the plant metabolism may have reduced the extrusion of¹³C. Towards senescence both nematode infection and drought reduced¹³C discrimination and increased water-use efficiencies indicating that then nematode caused water stress in the plants.     

Relation between cropping frequency of peas and other legumes and foot and root rot in peas

The relation between the frequency of legume crops in a rotation and the root rot severity in pea was examined in a field survey. Additionally, greenhouse experiments were performed with soil samples from legume rotation trials or from farmers' fields. The frequency of pea crops in current rotations proved to be much less than the recommended value of one in six years. The correlation between pea root rot and the number of years that pea or other legumes were not grown on the field under consideration (called crop interval) was weak. Root rot severity correlated better with the frequency of peas or legumes in general over a period of 18 years, but the frequency still explained only a minor fraction of the variation in disease index. Some experimental data pointed to the occurrence of a highly specific pathogen microflora with continuous cropping of only one legume species, but this phenomenon probably does not occur in farmers' fields. In field samples, root disease index for pea correlated well with that for field bean. The survival of resting structures of pathogens such asAphanomyces euteiches probably explains why the frequency of legume cropping has a higher impact than crop interval on root disease incidence. Pea-free periods and legume frequencies have a poor predictive value for crop management purposes.     

我国麻黄属的分类问题

本文对我国麻黄属植物进行了分类整理,计有2组15种2变种1变型。其中增补了国内原有12种4变种的记载,同时对易于混淆的种进行了讨论。     

稚蚕人工饲料中桑绿枝粉的添加效果及加工特点

在家蚕稚蚕人工饲料中分别添加 15 %的桑绿枝粉、冬桑条粉、桑皮粉等 ,并与豆腐渣、市售纤维素粉末等进行了对照试验 ,结果以添加桑绿枝粉的稚蚕人工饲料各项成绩最为理想 ,稚蚕对其有良好的摄食性 ,从而为研制稚蚕低成本人工饲料开辟了新的原料来源     

小果宜昌橙—柑桔属宜昌橙的新变种

本文对柑桔属宜昌橙(Citrus ichangensis Swingle)的一个新变种——小果宜昌橙进行了定名,并介绍了该变种的主要特征。 该变种形态类似宜昌橙,与宜昌橙的主要区别是子房心室少(5-7个),每个心室中胚珠少(3-4个),果实小。而宜昌橙子房心室7—10个,每个心室胚珠4-8个,果实较大。本变种为常绿乔木,树高3-5m,枝梢有刺,叶、花、果上均有油胞。果实长圆形,果皮紧、淡橙黄色,汁胞柔软,味酸苦,具有5—7个囊瓣。种子大、单胚,子叶白色。叶柄具翼,很宽大,大体上与叶片等长。主要分布于云南省的漾濞、巍山、保山、腾冲等县。