大豆种子劣变研究概况

大豆是重要的作物之一,也是蛋白质和优质食用油的良好来源。大多数的大豆生长在温带,但在亚热带、热带有逐步扩展的趋势。大豆种子形成过程及成熟后,在不良的自然环境(高温、高湿)中,种子生活力不断衰退,造成发芽率降低,称之为劣变。大豆种子劣变,影响种子收获质量、贮存质量、播种质量及商品性,也严重制约着大豆生产和种植区域的扩     

大豆种子抗劣变性的鉴定方法研究

以抗种子劣变性不同的５个栽培大豆和５个野生大豆品种为材料，比较了高温湿（相对湿度１００％，温度４０℃）条件下贮藏３天、７天、１０天和１４天及２０％的甲醇浸泡２小时等５种种子加速第化方法鉴定了种子抗劣变性的效果。结果表明，高温高湿老化７－１０天和２０％的甲醇浸泡２小时，可鉴定出大豆种子抗劣变性。     

不同包装材料不同贮藏条件对黄瓜种子发芽率的影响

跟踪了用铝箔袋、铜版纸袋和罐包装的黄瓜种子存放在不同条件下种子发芽率的变化情况.结果表明:随着贮藏时间的延长,贮藏在北方的3种包装材料包装的黄瓜种子,其发芽率变化差异未达到极显著水平;而贮藏在高温高湿的南方的3种包装材料包装的黄瓜种子发芽率差异达到了极显著水平,铝箔袋包装对黄瓜种子的保存效果最好.因此,在实际生产中,在高温高湿条件下,如果要较长时间存放黄瓜种子,宜采用铝箔包装材料.     

小麦种子安全贮藏的技术措施

小麦种子的发芽率高低与贮藏技术有着密切的关系，同时小麦收获时正逢高温多雨季节，极易吸湿回潮、生虫、发热、霉变，因此，掌握好贮藏技术是十分必要的：     

河北种质库部分作物种子生活力监测分析

对河北省种质库中21种作物1.3万多份种子进行了生活力监测,结果表明,①贮存12~17年后,94.55%以上的被监测种子发芽率仍保持在80%以上,但有292份种子(占被监测份数的2.00%)发芽率出现了明显下降(从80%以上降至70%以下)。②不同作物种子发芽率的变化趋势不完全相同,燕麦和冬小麦亲本两种作物种子平均监测发芽率出现了显著下降。同一作物不同品种、荞麦、冬小麦和玉米不同类型、燕麦入库不同批次、夏大豆不同收获年代等贮藏后发芽率的变化也存在明显差异。与黄粒玉米相比,白粒玉米监测发芽率显著低于入库发芽率,但尚需扩大监测品种数量以验证其普遍性。     

杂交稻种子劣变及提高发芽率的新技术

杂交稻增产显著,种植面积在国内外逐步扩展,从育种、栽培到种子生产已有一整套技术。近年来,生产上种子劣变问题较为突出,种子劣变影响收获质量,贮存质量,播种质量及商品性。研究延缓种子劣变,提高发芽率的技术已成为进一步发展杂交稻的措施之一。     

大豆种子生活力跟踪监测研究

对国家种质库贮存的５０份大豆种子进行生活力跟踪监测试验的结果表明，入库起始发芽率不同梯度的种子，在贮藏过程中，生活力的变化不同，品种间表现出明显差异；三个梯度监测种子发芽率的平均数，在各试验组内年度谙的没有大的差异，但品种间有差异；三个梯度监测种子发芽率的平均数，在各试验组内年度间没有大的差异，但品种间有差异。     

PEG处理对油松种子萌发的影响

以不同贮藏时间和不同贮藏条件下的油松种子为研究材料,利用正交试验设计对种子经PEG处理后的萌发情况进行研究,对种子发芽率、发芽指数、活力指数等指标进行统计。试验结果证实:PEG渗调处理有利于促进种子萌发;PEG分子量、PEG浓度、渗调时间和渗调温度都对种子引发效果有所影响;种子老化后经PEG渗调处理,种子活力有所恢复;PEG渗调条件应依据种子吸水特性和PEG溶液对种子吸水的影响进行选择。     

小麦种子贮藏方法

小麦收获时正逢高温多湿气候，即使经过充分干燥，入库后如果管理不当，仍易吸湿回潮、生虫、发热、霉变，贮藏较为困难，必须引起重视。1小麦种子的贮藏特性     

种子贮藏与发芽率的关系

短期贮存种子,常常也会遇到不良的贮藏条件,使种子的耐贮性发生变化,进而影响发芽率。本研究通过人工老化处理的办法,来研究种子在短期贮存中,温度、时间、品种三因素对种子发芽率的影响及其相互关系,为种子短期贮藏提供正确的科学分析。1 实验材料和方法     

Screening for Drought Tolerance: Evaluation of Seed Germination and Seedling Growth for Drought Resistance in Legume Plants

Experiments were performed to evaluate seed germination and seedling growth in simulated drought as screening techniques for drought tolerance raring. Several laboratory screening tests were evaluated for ability to estimate drought resistance in 18 cultivars of legume plants (field bean, soybean, field pea, lupine). Drought was simulated by a water solution of mannitol of chemical water potential ψ= -0.3 and -0.6 MPa. Both solutions significantly affected seed germination (final germination and promptness index) and seedling growth parameters (seedling height, dry matter of shoot and root as well as leaf injury by drought and high temperature). The tested cultivars could be grouped as drought resistant and drought susceptible plants. Drought tolerance ratings of legume plants in the laboratory tests were, on the whole, consistent with the ratings based on estimation of direct effects of soil drought on seed yield in field experiments. Measurements of electroconductivity of leaf diffusate to evaluate invisible injury caused by drought or high temperature were found to be an adequate criterion for drought tolerance rating. It is concluded that tolerance to drought stress in growing seedlings can be screened for by using mannitol containing nutrient solution. According to the results collected in this research, varieties differences in seed germination, seedling growth and leaf injury affected by drought or heat temperature were evident, however, not all treatments appeared to be equally useful for screening of legume species cultivars.     

充氮储藏对大豆老化劣变影响的研究

研究了充氮气调储藏对大豆老化的影响。控制氮气体积分数分别为98%和78%,比较了水分含量,储藏温度和储藏时间对大豆发芽率、浸出液电导率、丙二醛(MDA)含量和过氧化物酶(POD)活性的影响。结果表明,充氮储藏和普通储藏的大豆种子在储藏过程中发芽率会逐渐下降,水分12.2%的大豆在20℃储藏180d时发芽率保持在85%以上,而高温(30℃)高水分(14.9%)储藏大豆储藏至90d时,发芽率已降至零,种子完全丧失活力;充氮储藏的大豆浸出液电导率和丙二醛含量均比普通储藏的对照组大豆低,根据相关性分析,发芽率、电导率、丙二醛(MDA)和过氧化物酶(POD)存在极显著或显著相关性。充氮气调储藏能在一定程度上延缓大豆在储藏过程中的老化。     

Yield and Seed Quality of Mungbean as Affected by Irrigation in a Dry Season

A field study was conducted with the objective of determining the effects of soil moisture on seed yield and quality of mungbean ( Vigna radiata L. Wilczek) when grown under rainfed and irrigated conditions in a dry season. Seed quality was determined in terms of germination and production of normal seedlings after controlled deterioration. The presence of adequate soil moisture increased growth and yields of mungbean significantly. The seeds from irrigated plots had a greater weight, owing to heavier cotyledons. Although germination of seeds from the irrigated plots was higher before and after controlled deterioration for 72 h, the number of abnormal seedlings was also greater. Controlled deterioration reduced germination of both categories of seed in the same manner. These factors indicate the low potential of using seeds produced under irrigation in dry seasons as planting material, especially after storage.     

Yield Variation of Soybeans in Hawaii

In Hawaii, soybeans planted in November through January will produce yields of 25 to 50 percent compared with those planted through June. Yield components were studied for several soybean cultivars to determine which one was the most sensitive to planting dates and if there were differences between cultivars.
Soybean cultivars, Amsoy 71, Davis, Forrest, Kahala, P.I. 297,550 , and Williams were planted each month for two years. One November planting was lost, so there were 23 tests representing different environments. Each test consisted of 24 plots, six cultivars in four replications in a randomized block.
Analysis of variance of combined tests indicated significant differences between number of plants, pods per plant, seeds per pod, seed weight, yield of seed, plant height, and oil content of the seed that were due to data of planting, cultivar, and date × cultivar interaction.
Regression analysis indicated a closer relationship between pods per plant and yield during stress conditions (November through January plantings), whereas number of seeds per pod was more closely associated with yield during non-stress environments (April through June plantings).     

不同处理方法和贮藏时间对野生大豆种子萌发的影响

采用人工小刀破皮、低温冷冻和浓硫酸处理研究其对野生大豆种子发芽的影响，实验表明：-6——-10℃低温冷冻处理野生大豆种子1、3、5、7、9d可以一定程度的提高种子的发芽率；用体积分数为0．98的浓硫酸处理种子8—10min，对提高野生大豆种子的发芽率有明显的促进作用，发芽率可高达98％。室内贮藏1—4年的种子其发芽率没有明显差异。     

Planting Time and Seed Density Effects on Potato in Subtropical China

Planting times of potato in subtropical China vary and are often not optimal; their effects were studied in association with those of plant density. The research programme included 10 trials at three elevations (500, 750, 1200 m asl) in the spring and autumn seasons of 2 years with several contrasting varieties and different seed origins. Earlier planting in spring increased yield at 500 m asl. This effect was associated with better light use efficiency, higher rates of photosynthesis and more tubers per plant. At 750 m asl the effects of planting time in spring were the opposite: later planting increased yield. At 1200 m asl effects on yield were absent. Effects of planting time in autumn on yield were generally absent at all elevations, although plant stands at early planting were consistently and often severely reduced. Denser planting produced yields that were higher per unit area because of larger accumulated canopy cover but were lower per plant. Higher density consistently reduced plant stand. Density did not interact with planting time, not even in those experiments in which planting time also affected plant stands.
Optimal planting time depended on the amount of rainfall prior to planting especially in the autumn season, but also on cultivar and dormancy of the seed tubers used. The earlier variety yielded more than the later variety at low elevation, whereas the later variety yielded more at higher elevation. It is necessary to use cultivars that tuberize early to make better use of the limited growing period at lower elevation. The large variation of dormancy that affects plant growth and yield is caused primarily by differences in accumulated temperature sum (as affected by planting time, elevation of growth and storage, and season), genetics (variety), and their interaction with cultivation techniques.     

萌发过程中种子贮藏物质的动员和变化规律概述

种子萌发是植物生命的开端,此过程需要多种贮藏物质的动员来提供营养及能量,贮藏物质对种子萌发至关重要.本文概述了种子萌发所需主要贮藏物质(糖类、蛋白质、脂肪、磷)在种子萌发中的作用、动员情况和代谢变化规律,并与经劣变(老化)后的种子进行比较,从贮藏物质角度解析劣变对种子萌发和活力的影响,并对该领域未来的研究方向进行了展望...     

不同棉花品种种子活力对低温和人工老化胁迫的反应差异

为探讨棉花种子活力的品种差异及不同种子活力测定方法对棉子活力结果的影响,以17个棉花主栽品种(系)为材料,用简化的标准发芽、低温发芽和人工老化发芽3种方法测定棉花种子活力,并分析种子物理性状与种子活力的相关性。结果表明:3种活力测定方法下不同品种间种子活力均存在较大差异,各活力指标表现趋势也不一致,低温条件主要抑制种子幼苗的生长势,老化条件则主要抑制种子的发芽率。简化的标准发芽的活力指数与2种逆境发芽下的活力指数间的相关性较低。对3种测定方法的种子活力指标进行聚类分析,筛选出中棉所102、新陆中42、湘杂7号、XG39K5、屯杂6号及皖杂9号等高活力品种。低温和人工老化发芽条件显著降低了种子活力与种子各物理性状间的相关性。种子密度和健子率在不同发芽条件下均与种子活力关系最密切,可作为判断棉花种子活力大小的物理指标。     

不同水稻品种种子萌发生理特性差异研究

为研究不同水稻品种的种子萌发生理特性,根据24个水稻品种的萌发情况,筛选萌发速度差异的水稻品种5个,分别代表萌发速度快、中、慢3种类型。种子萌发生理特性结果表明,萌发期内发芽速度存在差异的水稻品种,其淀粉酶活性、可溶性糖含量均存在差异。萌发速度快的水稻品种‘盐两优888’和‘盐恢888’,其α-淀粉酶活性、β-淀粉酶活性高,有助于种子内淀粉的分解,同时这2个品种在萌发过程中可溶性糖含量高,为种子萌发提供了能量和物质。反之,萌发速度慢的水稻品种,种子淀粉酶活性低、可溶性糖含量低。说明水稻种子中淀粉酶的活性、可溶性糖含量与种子萌发速度呈正相关。     

春播和秋播对南方春大豆种子活力的影响

试验采用春播（４月４日）和秋播（７月３０日）两种播期法，研究春播种子活力低，秋播种子活力高的生理生化原因，结果表明，种子发芽率，发芽指数，电导率，过氧化物酶活性和真菌侵染率，这些反映种子活力的生理指标，秋播种子均优于春播种子，此外，秋播种了表皮结构较春播种子致密，种子表面小孔数目少而小，这可能也是秋播种子活力高的原因之一。