我国林木种子活力研究概述

对种子活力的抗逆性及影响林木种子活力的内外因素进行全面探讨，并对种子活力的生理、生化指标和物理指标测定方法作了系统回顾，同时讨论了提高种子活力的种子收获、加工、贮藏预处理以及静电、磁场处理等研究概况。     

杉木种子活力研究

通过生理、生化途径对杉木三个种源种子活力的初步研究表明：发芽率、幼根平均长度、发芽指数、发芽高峰值、活力指数等生理发芽指标间紧密相关；在生化指标中，过氧化物酶活性与种子日平均发芽的率的波动呈规律性变化；电导率亦随种子活力的高低而波动。     

樟子松种子园种子质量的评定

林木种子质量的评定通常是以净度、千粒重、含水率、发芽率等指标为依据的。然而,仅用以上指标表示种子的好坏是不完整也不深刻的,尤其是发芽率的测定结果不能全面反映种子的发芽速率及幼苗生长特性。因而,国外早在50年代初就提出了种子活力的概念。种子活力应包括种子的发芽速率、幼苗生长速率及种子对不良环境条件的忍受能力。种子活力是一个决定于基因型,而又受环境因素影响的生理特性。经过种子活力测     

高温高湿对香椿种子活力的影响

种子活力是指种子的健壮度,是由基因所决定而又为环境所改变的一种生理特性。种子成熟后,外界因子对其活力产生影响,改变活力水平。为了保护种子活力,需要弄清环境因子对种子活力的作用规律,并以此为基础制订防止种子活力下降及提高种子活力的措施,服务于生产实践。香椿是优良的用材和木本蔬菜树种,各地广为发展。研究香椿种子活力,不仅可以     

脱氢酶活性与杉木种子活力的关系

幼根、幼苗的活力状况,认为是种子活力的一个重要的、全面的综合表现,已为众多的试验所证实。我们自1982年冬至1985年连续3年,用杉木嫁接初级种子园单亲子代为材料进行了试验。结果田间幼苗重量与种子活力相关密切。为深入了解影响幼苗重量的种子的作用,必须对种子的生理生化基础作进一步的研究。 TZ法已被国际上用来作为鉴别种子生命力和测定种子活力的简易可行的测定方法。在杉木上应用TZ法来比较各单亲子代间种子活力的大小以及它们之间的相互关系,尚未见报道。我们做了一系列的测定,现将试验结果整理如下。     

经济林种子生理研究进展

经济林种子是育苗、造林的物质基础,种子品质的好坏直接关系到苗木生产及造林的成效。本文就经济林种子的休眠与萌发、种子的老化及劣变、种子活力等种子生理工作研究现状进行了较为系统的总结,并提出了今后经济林种子生理的研究方向和发展趋势。     

毛竹种子人工老化过程中生理生化变化

研究人工老化过程中毛竹种子活力及其生理生化变化过程.结果表明:人工老化处理后,种子发芽率、发芽指数和活力指数均先快速下降后缓慢下降,活力指数下降较发芽率和发芽指数快.老化6天时活力指数下降72％,老化12天时种子活力基本丧失.伴随着种子活力下降,表现出种子浸出液相对电导率和可溶性糖含量升高,MDA含量升高,POD,SOD和CAT酶活性降低,可溶性蛋白质含量降低,内源GA3和IAA含量降低,ABA含量升高,GA3/ABA比值降低等一系列生理生化变化.相关分析表明:SOD活性、CAT活性、可溶性蛋白和GA3,IAA,GA3/ABA,与种子活力呈极显著正相关;种子浸出液相对电导率、MDA和ABA含量呈极显著负相关.膜脂过氧化引起的生物膜损伤是加速毛竹种子老化的重要原因,内源激素失衡也是影响种子萌发和加速老化的主要因素之一.     

杉木速生早期预测技术及生理生化基础的研究

1982年冬至1989年,我们开展了从种子阶段进行杉木速生早期预测技术及其生理生化基础的研究。在多年测试与种子活力有关的生理生化指标和大田多点试验,正反验证结果,表示种子活力的幼苗重量与高生长关系密切,与六年生以上杉木生长相关程度达80～90%以上。高活力家系与对照相比,其生长优势达到10%左右。表明以种子活力状况预测杉木速生与否是可能的,也是可靠的。     

木麻黄嫁接种子园种子活力比较研究初报

种子活力,据Woodstock(1965)认为,是指种子能否适应各种环境条件而迅速、整齐地萌发的能力。由于林木生产周期性长,因此,应用种子活力的大小来早期鉴定种子品质;预测种子在田间条件下生产能力,在国内外愈来愈被人们所重视。本试验采用活力指数、发芽值等生理指标,对木麻黄嫁接种子园内30个家系及对照的自由授粉     

书讯

由中美著各种子生理学家赵国芳、郑光华、陶加龄(美籍华人)等教授和浙江林科所史忠礼副研究员合作编著的《实用种子生理学》,已由农业出版社于1990年9月出版发行。全书计500多页,40余万字。共分9章69节。有结论,种子发育生理,种子活力,     

杉木种子园种子生物学特性的地区及年度变异

本研究目的在于揭示杉木种子园种子品质的变异模式。在1981—1983和1986年,对分布区内不同地区的70个种子园的种子取了样,并进行三个特性即发芽率、涩粒率和千粒重的测定。结果表明,经研究的种子特性在不同年份间和种子园间均存在变异:千粒重随种子园的地理经度降低而变轻;其它两个性状表现出非渐变的生态型(地域性)变异模式。发芽率的变异模式与涩粒率的模式相并行,但二者之间为负相关。这些发现为育种工作者确定建立最适宜的杉木种子园地区,提供了科学依据。     

ORGANIC SUBSTANCE METABOLISM DURING SEED GERMINATION OF PINUS BUNGEANA

The metabolism of fats,proteins and carbohydrates and change of enzyme ofseeds of pinus bungeana during the germination were conducted by the methods of gas-—liquid chromatography,flow injection,colorimetric analysis of spectrophotometer,toprovide theoretical basis for seeds dormancy,germination and storage of seeds of foresttree.The results indicate that(1)carbohydrates were first utilized during germination ofseed of pinus bungeana;(2)stored substances in seeds began to decompose quickly afterradicale broke through seed coats;(3)the activity of enzymes in the seeds does not alwayscoincides with the increase or decrease in quantity of its responsible substance duringgermination of the seed.Changes in stored substance relate to metabalism of othermetabolism of other materials and the use of hydrolysates.     

生根粉提高仙客来种子活力的初步研究

采用不同剂号,不同浓度的新剂型ＡＢＴ生根粉浸泡处理仙客来种子,测定了种子发芽率,发芽速率,发芽指数,活力指数,干鲜比等种子活力指标和电导率,可溶性糖含量等部分生理生化指标,并结合仙客来育苗生产调查出了苗率。     

初论杉木种子园的园址选择

通过6个省内28个种子园的数据分析,发现位于杉木不同产区(北部产区、中心产区、南部产区)的种子园,其开花结实年龄、结实量、种子播种品质等均存在较有规律的差异。中心产区无性系一般开花结实迟于北部产区的无性系;产量和种子品质的年变幅大;历年平均产量、球果出籽率和种子发芽率显著低于北部产区。就上述趋势对影响杉木种子生长发育的主要环境因子进行了理论上的讨论分析,并提出杉木种子园园址选择的初步意见。     

杉木种源种子园种子产量和质量分析

1988年在吉安市青原区白云山林场营建的我国第一个杉木种源种子园(面积15hm^2)于1990年开始投产后。每年所产的种子都用于江西及其它省区重点工程造林,产生了较大的经济和社会效益。由于本种子园在营建之初就考虑了影响种子园种子产量和质量的诸多因素．与现有其它杉木种子园相比,在种子产量和质量方面都有较大程度的提高：1990-1997年,平均年产种量为39．45kg／hm^2,平均发芽率达52．05％,最高达78％,远高于我国杉木一级种子发芽率的标准(45％)。杉木种子如此高的发芽率尚未见诸报道。     

Seed Size as a Predictor of Germination Success and Early Seedling Growth in ‘Hollong’ (Dipterocarpus macrocarpus Vesque)

In species with seeds losing viability shortly after dispersal and exhibiting inherently low germination, quick decisions are required with respect to seeds that should be selected to maximize germination success and vigorous growth of seedlings. In ‘hollong’ (Dipterocarpus macrocarpus Vesque), I address the following questions: (a) are seeds that germinate randomly distributed within a seed population, (b) are subpopulations of viable and non-viable seeds separable, (c) does seed size predict which seeds germinate and (d) does seed size predict time required for germination and seedling vigour? Two estimators of seed size, diameter and weight, demonstrated a significant positive linear relationship endorsing assumption that accumulation of mass increases with increase in diameter of seeds. A threshold for selection of potential seeds for germination could not be derived from diameter measurements since seeds in an entire range of diameter did or did not germinate. All seeds <11 g did not germinate, but this threshold lies at the far lower end of the weight range and allows rejection of only a few seeds and acceptance of many seeds that will not germinate. A risk of potential seeds being rejected or non-viable seeds being picked exists if selection was derived from either diameter or weight. However, viable seeds could be better predicted from a scatter-plot of diameter on x-axis and weight on y-axis. Seeds showed a fan-shaped scatter and those developing the lower blade of the fan did not germinate while those following the handle were successful. Hence, two subpopulations segregated, but with a fuzzy edge. Mean diameter and mean weight of germinated seeds were significantly greater than those of ungerminated seeds. Most ungerminated seeds were those that had relatively smaller weight compared to their diameter. Although some large diameter seeds with small weight did germinate, but failed to develop into seedlings. Germination time and seedling vigour parameters (height, leaf number and collar diameter) were correlated both with diameter and weight. However, weight appears to have mattered more than diameter in germination success and early seedling growth.     

Effects of artificial environmental conditions on anatomical and physiological ripening of Pinus sylvestris L. seeds

To determine suitable conditions for artificial ripening of Scots pine seeds, cones collected on seven occasions between August 6 and November 26, 1990, in northern Sweden, were subjected to artificial ripening at different temperatures (+5°–+15°C) and cone moisture contents for 3–9 weeks. Complete physiological ripening and improved seed vigour were attained after artificial ripening if collection occurred no earlier than the beginning of September. The highest germination percentage after artificial ripening, ca 90%, was achieved for seeds collected after the anatomical ripening in nature had ceased and was at least as high as for seeds ripened in nature. Temperature did not influence ripening, whereas a low cone moisture content impaired ripening of those seeds collected earliest. The germination percentage was not influenced by 2–6 months of cone storage subsequent to artificial ripening, but seed vigour was impaired. Anatomical ripening during artificial ripening was very limited.     

ABT生根粉提高报春花种子活力的研究

为 提高报 春花种子 活力和幼 苗的抗 逆性 , 以 Ａ Ｂ Ｔ 生根 粉 不同 剂型 、不 同浓 度浸 泡 处理报春花 种子, 进 行了播种 发芽试 验。结果 表明 , 经 Ａ Ｂ Ｔ 生 根粉 浸 泡处 理 后, 发 芽率 、发 芽速率、发 芽指数、 活力指数 等活力指 标均明 显提高, 以６ 号 Ａ Ｂ Ｔ 生根 粉２０ ｍｇ Ｌ 浸泡２４ｈ 的处理效果最 佳。电导 率值和干 鲜比低 于 Ｃ Ｋ, 与种子 活力存在 负相关 关系。     

Variation in seed traits and seedling vigour of Cordia africana Lam.provenances in Ethiopia

Cordia africana is a very important indigenous tree species for timber and other products and services in Ethiopia.Seed traits and seedling vigour of seeds from 12 provenances of the species were compared.Mean seed mass for each provenance was assessed for 1000 seeds in10 replications,and seed length and width were measured for 100 seeds in four replications per provenance.Germination was assessed in a glasshouse taking 400 seeds from each provenance.Root collar diameter and height of 440 seedlings grown in a nursery for 290 days in Addis Ababa were measured.Seed length,seed width,seed mass,and shoot height and root collar diameter of seedlings showed significant differences(P0.001) among provenances.Correlation analysis between seed and seedling traits and environmental variables revealed significant positive correlations between seed width and germination percentage,seed width and altitude,seed width and longitude and seed length and latitude.Negative correlations were obtained between seed width and temperature,seed width and rainfall,seed mass and temperature,and germination and temperature of the seed source.As expected,differences in seed trait did not explain the variability in seedling vigour.Determining quantitative variations in seed traits and seedling vigour among provenances and the patterns along environmental gradients are essential for informing decisions on the tree improvement programme of the species.     

Variation in seed traits and seedling vigour of <Emphasis Type="Italic">Cordia africana</Emphasis> Lam. provenances in Ethiopia

Cordia africana is a very important indigenous tree species for timber and other products and services in Ethiopia. Seed traits and seedling vigour of seeds from 12 provenances of the species were compared. Mean seed mass for each provenance was assessed for 1000 seeds in 10 replications, and seed length and width were measured for 100 seeds in four replications per provenance. Germination was assessed in a glasshouse taking 400 seeds from each provenance. Root collar diameter and height of 440 seedlings grown in a nursery for 290 days in Addis Ababa were measured. Seed length, seed width, seed mass, and shoot height and root collar diameter of seedlings showed significant differences (P < 0.001) among provenances. Correlation analysis between seed and seedling traits and environmental variables revealed significant positive correlations between seed width and germination percentage, seed width and altitude, seed width and longitude and seed length and latitude. Negative correlations were obtained between seed width and temperature, seed width and rainfall, seed mass and temperature, and germination and temperature of the seed source. As expected, differences in seed trait did not explain the variability in seedling vigour. Determining quantitative variations in seed traits and seedling vigour among provenances and the patterns along environmental gradients are essential for informing decisions on the tree improvement programme of the species.