作物QTL定位常用作图群体

作物大多重要农艺性状是数量性状,受多基因控制,基因之间及基因与环境之间都会发生互作,这为研究带来了很大的不便。因此,好的QTL作图群体,是研究QTL间的互作、QTL与环境的互作、QTL定位以及基因克隆的最根本保障。随着分子标记技术的发展,QTL定位的作图群体也在不断的发展并逐渐满足研究者对于QTL的精细定位及基因克隆等研究的进一步要求。文章主要综述了作物QTL定位常用作图群体的构建及优缺点。     

西双版纳少数民族地区主要作物地方品种调查与分析

对云南省西双版纳傣族自治州勐海县和勐腊县的傣族、哈尼族、拉祜族、彝族地区的作物地方品种进行了调查,收集了粮食作物、蔬菜、果树、经济作物的地方品种和野生资源样本共353份,分属40科71属87种。通过分析上述调查资源的特性及分布特点,基本明确了西双版纳傣族自治州主要作物资源的保存现状,揭示了不同少数民族的传统喜好、宗教祭祀以及不同生态环境对作物种质资源多样性保存的作用。针对该地区作物种质资源的特性,提出了西双版纳少数民族地区主要作物地方品种的保护策略。     

N,P供给对作物排放N2O的影响研究初报

Ｎ、Ｐ供给对作物排放Ｎ_２Ｏ的影响研究初报陈欣,沈善敏,张璐,吴杰,王学强（中国科学院沈阳应用生态研究所,沈阳１１００１５）ＡｐｒｅｌｉｍｉｎａｒｙｒｅｓｅａｒｃｈｏｎｔｈｅｅｆｆｅｃｔｏｆｎｉｔｒｏｇｅｎａｎｄｐｈｏｓｐｈｏｒｕｓｓｕｐｐｌｙｏｎＮ_...     

催化示波极谱法测定农作物中的微量铅

1 前言 农作物中铅的含量在很大程度上反映出土壤和成土母岩中铅的水平。铅是一种有毒元素,人体摄入过量的铅,就会导致一系列的病变。因此,农作物中铅的测定对调查和评价环境中铅的污染,估算人畜食入铅的量,研究各类因铅中毒引起的疾病,做到对症下药具有十分重要的意义。本文根据前人的经验研     

Biological Control of the Bulb Mite, Rhizoglyphus robini , by the Predatory Mite, Hypoaspis aculeifer , on Lilies: Predator-Prey Dynamics in the Soil, under Greenhouse and Field Conditions

We tested the capacity of the soil-dwelling predatory mite, Hypoapsis aculeifer , to control mites attacking lily bulbs. Experiments in the greenhouse and in the field showed that in the absence of predatory mites populations of the bulb mite, Rhizoglyphus robini , on lily bulbs increased, whereas the release of predatory mites either slowed down the increase - as observed in the field - or caused the bulb mites populations to decrease - as observed in the greenhouse. In all cases the population of predatory mites increased as long as bulb mite densities were not too low. However, within the first week after predator release there was usually a sharp decline to 10-40% of the original number released. Greenhouse experiments on intact lily bulbs in pots, boxes and 1 m 2 plots with peat soil showed that when released in a ratio of 1 predator to 2 or 5 prey, the predatory mite, Hypoaspis aculeifer , suppressed populations of bulb mites to less than 10 individual per bulb within 6 weeks. Elimination of bulb mites was observed only when the predator-to-prey ratio at release was equal to 3:1. Field experiments in 2 m 2 plots with intact bulbs in rather compact sandy soil showed that when released in ratio of 1 predator to 1 or 2 prey, the predatory mite, H. aculeifer , did not cause the population of bulb mites to decrease, but it did reduce their population growth. The initial predator-to-prey ratios required to achieve suppression (ca 1:2) or elimination (3:1) in the soil environment are much higher than those required for bulb mite elimination when lily bulb scales were embedded in a medium of vermiculite (ca 1:20). Among the possible causes are: (1) the initial losses of predators in the greenhouse and even more so in the field due to mortality and/or emigration from the experimental plots; (2) the lower temperatures in the greenhouse and especially in the field, which slow down the growth and predation processes and thereby delay prey extinction; and (3) the spatial complexity of the soil environment which creates refuges for the bulb mites.     

闪电河流域6种农作物磷元素含量动态变化规律研究

本文报道了闪电河流域１５种植物磷含量特征及６种农作物含磷量的动态变化规律。结果表明：闪电河流域植物平均含磷量为１．３８±０．６２ｍｇ·ｇ￣（－１）,最高达２．２５ｍｇ·ｇ￣（－１）,最低只有０．８８ｍｇ·ｇ￣（－１）,与海河流域及锡林河流域植物磷含量基本一致。６种农作物在整个生长期间的磷含量变化规律表现为三种类型：禾本科植物小麦（Ｔｒｉｔｉｃｕｍａｅｓｔｉｖｕｍ）、莜麦（Ａｖｅｎａｎｕｄａ）和油料作物类亚麻（Ｌｉｎｕｍｕｓｉｔａｔｉｓｓｉｍｕｍ）,果实成熟期＞幼苗期＞营养期（Ｐ＜０．０５）;豆科作物豌豆（Ｐｉｓｕｍｓｅｔｉｖｕｍ）和蚕豆（Ｖｉｃｉａｆａｂａ）幼苗期＞营养期≥果实成熟期（Ｐ＜０．００１）;块茎类作物马铃薯（Ｓｏｌａｎｕｍｌｕｂｅｒｏｓｕｍ）则表现为营养期＞幼苗期＞果实成熟期（Ｐ＜０．００１）。６种农作物不同器官部位中根、茎、叶表现为幼苗期＞营养期＞果实成熟期（马铃薯除外）,而果实则为成熟后期＞果实形成期。不同器官磷含量比率的变化可反应磷在根、茎、叶、果４个器官的迁移清况,研究认为植物磷在幼苗期及营养期,通过根→茎→叶迁移,而在果实成熟期则通过根→茎叶→果途径运输。     

Nitrogen assimilation in plants: current status and future prospects

Nitrogen(N) is the driving force for crop yields; however, excessive N application in agriculture not only increases production cost, but also causes severe environmental problems. Therefore, comprehensively understanding the molecular mechanisms of N use efficiency(NUE) and breeding crops with higher NUE is essential to tackle these problems. NUE of crops is determined by N uptake, transport, assimilation, and remobilization. In the process of N assimilation, nitrate reductase(NR), nitrite redu...     

几种作物的生理指标对土壤水分变动的阈值反应

 在生长盛期,谷子、高梁、冬小麦的气孔导度、叶水势和光合速率在一定土壤含水量范围内并不随着土壤含水量的降低而发生明显变化,只有当土壤含水量低于一定程度时,才随着土壤湿度的降低而减少,表现为对土壤水分有明显的阈值反应。不同作物此阈值下限存在差异,高粱在大于田间持水量42％～45％的根层土壤湿度条件下,气孔阻力和叶水势基本维持恒定;谷子的这个指标在50％左右,冬小麦在60％左右。而夏玉米在所试土壤湿度范围内(20％～30％土壤体积含水量),气孔阻力和叶水势基本维持不变,而光合作用随着土壤含水量的增高而出现增加趋势。表明在这4种作物中,只有玉米需要充足的水分供应才能维持其良好的生长发育,而高粱具有比其它3种作物更强的适应土壤水分变动能力,从而比其它作物更抗旱和耐旱。     

三种农作物中镉积累与全硫含量的关系

采用田间试验方法,研究了土壤中镉浓度分别为2和5 mg·kg^-1时,向日葵(Helianthus annuus)、玉米(Zea mays)和大豆(Glycine max)从苗期至成熟期各生长阶段茎叶中镉积累与全硫含量的关系。结果表明,玉米和向日葵各生长时期茎中镉含量与其全硫含量呈极显著相关,叶片中镉含量与硫含量没有相关性,说明硫在植物镉的运输过程中发挥着重要的作用。土壤中镉浓度为2 mg·kg^-1时,籽实中镉含量从高到低的顺序是：向日葵＞大豆＞玉米;土壤中镉浓度为5 mg·kg^-1时,籽实中镉含量从高到低的顺序是：大豆＞向日葵＞玉米,与籽实中硫含量的高低顺序一致;玉米籽实中镉含量最低,在2个镉浓度处理下平均值仅为0.01和0.03 mg·kg^-1,低于国家标准食品中镉限量值。