梯度磁场对水稻幼苗生长发育影响的研究

本文用梯度磁场处理早稻２号,旱粳子,中百４号和越富四个品种的水稻种子,同时测定了水稻幼苗叶片的叶绿素,脯氨酸,蛋白质含量和膜透性以及ＳＯＤ,ＰＯＤ活性的变化来研究梯度磁场对水稻幼苗的生物学效应,结果结果;处理后,叶绿素,脯氨酸和蛋白质含量增加,ＳＯＤ活性升高,膜透性降低,ＰＯＤ活性下降,蛋白质的电泳图谱表明,磁场处理的四个水稻,其蛋白质带和形状相同,但影响蛋白质的表达。     

花生种子的磁处理对其萌发及幼苗生长的影响

本试验着重研究了用交、直流磁场对花生种子进行处理后,在种子萌发及幼苗生长过程中产生的影响。结果表明,一定强度的交流或直流磁场对种子的萌发及幼苗生长有一定的促进作用。处理过的种子存放一年后,磁场对种子萌发的作用依然存在。     

南亚热带森林24种乔木的种子萌发和幼苗生长

以膨胀珍珠岩为基质,在光和暗的条件下,对２４种南亚热带森林乔木的种子萌发和幼苗生长进行了研究。种子的形态和重量与种的演替阶段有关,种子的重量也与不同的种有关。不同种的萌发率差异较大,种子较大的种,萌发率较高。肉质果实的种子,开始萌发的时间较长。光和暗条件对萌发率和萌发速度无明显影响。幼苗高度和种子重量呈正相关,这一相关在光条件下比暗条件下更明显。暗条件明显地引起群落演替早期的树种的茎徒长,限制根的生长,而对演替后期种无显著的影响。幼苗地上部分和根系生物量的分配与种的演替阶段有关,也与不同的科有关。幼苗地上部分和根系生物量的分配也受光暗条件的影响,而不受种子重量的影响。根和叶的生物量分配和种在其群落演替阶段有关。幼苗的生物量与种子重量有显著的正相关。幼苗的相对生长率相差较大,在没有营养供应的生长基质中,以演替中间阶段的种的相对生长率较大。幼苗从种子的物质利用效率与种子重量呈负相关,而与种的演替阶段无明显的相关。     

南亚热带森林几种乔木种子萌发和幼苗生长观察

本文对香椿（Ｔｏｏｎａｓｉｎｅｎｓｉｓ（Ａ．Ｊｕｓｓ．）Ｒｏｅｍ．）、木蝴蝶（Ｏｒｏｘｙｌｕｍｉｎｄｉｃｕｍ（Ｌ．）Ｖｅｎｔ．）、扁斗青冈（ＱｕｅｒｃｕｓｈｕｉＣｈｕｎ）、泡桐（Ｐａｕｌｏｗｎｉａｆｏｒｔｕｎｅｉ（Ｓｅｅｍ．）Ｈｅｍｓｌ）罗浮柿（ＤｉｏｓｐｙｒｏｓｍｏｒｒｉｓｉａｎａＨａｎｃｅ）、枳（ＢｅｒｃｈｅｍｉａｄｕｌｃｉｓＴｈｕｎｂ．）等南亚热带森林乔木种子萌发和幼苗生长进行观察．香椿、扁斗青冈、罗浮柿种子在轻阴（５５％光）条件下萌发率最高,分别为７０％、９０％、３０％,木蝴蝶种子在重阴（３８％光）条件下萌发率最高,为８０％,枳种子在光照条件下萌发率最高,为１５％．阳性树种香椿、木蝴蝶、泡桐、枳幼苗生长速度较快,属速生型树种,其幼苗在光照条件下生长速度最快,森林中树种扁斗青冈、罗浮柿幼苗生长速度较慢,属慢生型树种,其幼苗在轻阴条件下生长较好．随着施肥量的增加,幼苗生长速度明显提高．     

FIELD GERMINATION AND SEEDLING GROWTH OF CH AND CL PROGENY OF IMPATIENS CAPENSIS (BALSAMINACEAE)

The germination behavior and early growth of chasmogamous (CH) and cleistogamous (CL) progeny of Impatiens capensis were investigated in two eastern Nebraska stands. Field germination of families of buried seeds was scored in mid-April. In one stand a significantly higher proportion of CL seeds germinated than CH seeds while no significant differences were observed in the second stand. Among-family variation in germination rates was significant in both stands. The time course of field germination was similar for CL and CH seeds. A sample of the germinated CL and CH seedlings, matched in size, was planted individually in pots and grown in the greenhouse for five wk. Early growth of CL and CH seedlings was similar. In addition, CL seedlings were as variable as CH seedlings for four morphological traits. Overall, a large fitness advantage for CH progeny was not detected in the germination and early growth of Impatiens capensis seedlings.     

不同浓度MNP与水稻种子萌发和幼苗生长间的相关性研究

MNP（2-methoxy-5-nitro-phenal的钠盐)是一种植物生长调节剂,它是笔者参照类似物的合成原理和方法研制而成。本文研究了MNP对水稻种子萌发和幼苗生长的作用,从而为合成物MNP在农业上的应用。提供了科学依据。     

GERMINATION AND GROWTH OF CELOSIA CRISTATA L., UNDER VARIOUS LIGHT AND TEMPERATURE REGIMES

Continuous light or alternating light and dark appear to be necessary for good germination of Celosia cristata L. As temperature increased up to 31 C so did germination; thereafter, it decreased. There appears to be a preference for high constant or high alternating temperatures in germination. As light intensity decreased so did growth in terms of leaf area, dry weight and relative growth rate. Proportionally more leaf is also made and leaf:area ratio increased. However, root weight ratio decreased. Although both high light intensity and high temperature are required for the good growth of Celosia, temperature appeared to be more important than light. A reduction of less than one-third of full light may not cause a significant reduction in growth. The results explain the observed differences in the nature of C. cristata in the field as well as its distributional limits.     

GERMINATION AND GROWTH OF BIRD-DISPERSED PLANTS: EFFECTS OF SEED SIZE AND LIGHT ON SEEDLING VIGOR AND BIOMASS ALLOCATION

I examined germination and seedling growth in nine species of fleshy-fruited plants from Washington and Idaho to assess their relative responses to sun and shade. I allowed seeds to germinate over a period of 500 days, and grew the seedlings in a greenhouse for 35 days prior to harvest. Cumulative percentage germination of six species approximated logistic curves. Species with larger seeds were more shade-tolerant, which resulted largely from greater biomass allocation to roots by these species. Seedlings of Rosa gymnocarpa, Sorbus scopulina, Symphoricarpos albus, Clintonia uniflora, and Streptopus amplexifolius grew larger in open sun than in shade (35% open sun), whereas those of Actaea rubra, Disporum trachycarpum, Smilacina racemosa, and Smilacina stellata showed no differences. Percentage root biomass was higher in sun than in shade for R. gymnocarpa, S. scopulina, S. albus, C. uniflora, and S. amplexifolius, but lower for S. stellata. In C. uniflora, S. racemosa, and S. stellata, seeds from unripe fruits failed to germinate. The results suggest that light gaps resulting from periodic disturbance of canopy influence recruitment of bird-dispersed species differentially and thereby contribute to maintaining high species richness and diversity in understories of temperate coniferous forests.     

沙冬青种子萌发及幼苗生长特性

沙冬青(Ammopiptanthus mongolicus)是亚洲中部荒漠特有种,由于其分布的环境条件特殊,现存植被天然更新困难,人工育苗、造林存在一定问题。为改善种皮透水性,获得整齐一致的发芽,分别用21.5 (室温)、40、60、80和90 ℃的温水浸种5 min。结果表明: 60 ℃温水浸种效果最好,与对照相比,显著地提高了种子发芽势,并有效地降低硬实率。对比分析了15、20、25、30、35和40 ℃环境温度下种子萌发的特性,种子发芽最适温度是30 ℃,而胚根及下胚轴伸长最快的温度为25~30 ℃。较低温度下种子发芽延续时间较长,并且种子萌发后下胚轴和胚根伸长缓慢,易形成畸形(胚根严重扭曲、缢裂)幼苗。15 ℃时畸形幼苗占发芽种子数的28.1%,而30~40 ℃时仅占5.2%~8.6%。温度过高不利于种子萌发及幼苗生长,40 ℃时,吸胀种子绝大部分丧失活力,发芽种子在35 ℃以上温度下生长2~3 d,胚根胚轴组织呈水渍状坏死。另外,催芽后的种子播种在河沙中子叶出土最快,出土率可达63%,显著高于在粘质壤土中出土率(11%)。不同粒径的种子播种后幼苗生长特性表现出一定的差异,粒径5 mm以下小粒种子播种后幼苗长势弱,苗期成活率低,生长70 d后幼苗成活率仅为35.4%,而粒径5 mm以上种子同期幼苗成活率达56.2%。据上述试验结果,结合自然分布区内环境条件的资料,分析了沙冬青濒危原因,并为植被恢复育苗措施提出建议。     

各种酵母菌经超低温冻结和融化后的反应

本文报告用液氮超低温(-196℃)冻结和融化后,对酵母菌的影响。34种酵母菌经慢速(冷却速度为1℃/min)冻结后细胞成活率普遍高于快速(冷却速度为450℃/min)冻结。10%甘油和10%二甲亚砜比水在冻结中呈现出显著的保护作用。冻结保藏4个月后,细胞成活率都在11%以上,最高达97%,平均70.4%,而水,最低者仅0.4%,最高87%,平均46.5%。所观察的白地霉 Geotrichum candidum As 2.361,椭圆酿酒酵母 Saccharomyces cere-visiae var.ellipsoideus AS 2.541,八孢裂殖酵母 Schizosaccharomyces octosporus AS 2.1148,其细胞在冻结过程中的形态,最初质壁分离,继之整个细胞收缩,而融化后则可复元.解脂假丝酵母 Candida lipolytica AS 2.1207和2.1405经冻结48小时以上,融化后的细胞悬液直接接种培养后检测脂肪酶活力;酿酒酵母 Saccharomyces cerevtsiae AS 2.399和椭圆酿酒酵母 As 2.541冻结48小时后乙醇发酵力;异常汉逊酵母 Hansenula auomala AS 2.300和 AS 2.470冻结后形成乙酸乙酯的能力,都无明显的减退,而且以甘油作保护剂的细胞,较未经冻结者呈现出稍强的活力。就代谢产物而言,用气相色谱法分析发酵液,乙醇或乙酸乙酯都是很纯的终产物。嗜渗压的固囊酵母 Citeromyces matritensis AS 2.1401和汉逊德巴利酵母 Debaryomyceshansenii AS 2.45冻结后的细胞耐 NaCl 的能力无改变.冷冻真空干燥法保藏菌种,适合的菌类较广,是久经考验的方法。但是对于酵母菌冻干后细胞成活率平均为8.6%,而超低温冻结24小时细胞成活率平均为86.7%,大了10倍。     

稀土元素对甜菜种子萌发,幼苗生长及块根产量的影响

本文研究了稀土元素对甜菜的生物效应。结果表明,稀土元素可显著地提高种子萌发率,促进幼苗生长,增加幼苗根系活力、叶片净光合速率与块根产量,并明显地降低了甜菜叶片细胞膜在低温下的透性,即提高了叶片的抗寒力。     

水青冈林中两种鹅耳枥种子萌发和幼苗的生存与生长（英文）

 千金榆(Carpinus cordata var．chinensis)和千筋树(Carpinus fargesiana)是四川省北部山地水青冈林中的两种主要落叶阔叶树。两种植物种子萌发和幼苗生存与生长的实验研究结果显示：千金榆种子秋季成熟落地后有一年多的休眠期,种子主要在落地后的第二和第三个生长季萌发;千筋树种子成熟落地后有的可在来年萌发,但大部分是在第二个生长季萌发;由于每2～3年两种树就有一个较大的结实年,每年都会有一些新的幼苗在林中出土;尽管两种树是耐荫的,但幼苗在较好光照条件下(如林窗)生存和生长明显好于在林冠遮荫的地方;施肥会加速幼苗的死亡,特别是在阴暗的林下,但在光照较好的条件下能促进幼苗的生长。结果说明两种鹅耳枥的幼苗可以在林下持续存在,但只有在较好的光照条件下,如稀疏的林冠下或林窗下才会有明显的净生长。     

高浓度氧对种子萌发和幼苗生长的伤害

绿豆、木豆和水稻等种子在氧气下萌发生长会引起不同程度的氧伤害,这种伤害不因二氧化碳、光照和温度条件的改变而减轻或消除。水稻萌发生长对高浓度氧的忍耐是有限度的,氧处理1～2天后移置空气中,能恢复生长;处理3～4天恢复生长缓慢;处理5天失去生长能力。种子萌发的氧伤害,表现出种子吸水膨胀率和浸泡液电导率较高,糖和蛋白质外渗量大,以及膜脂过氧化产物丙二醛含量较高。     

黄腐酸和汪平酸对小麦种子萌发与幼苗生长及绿豆下胚轴生根的影响

用黄腐酸和汪平酸浸种后,对于小麦种子萌发无明显影响。用不同浓度的黄腐酸和汪平酸溶液培养小麦幼苗,发现适当浓度时对于幼苗及根系生长与分化有促进作用,高浓度则表现为抑制作用。10ppm黄腐酸和50ppm汪平酸可显著增加去根绿豆下胚轴再生根数,而且在一定的浓度范围内,随着浓度的增高,根数不断增加而根长却逐渐减短。