不同处理方法对几种牧草种子发芽率的影响

主要对白三叶、紫花苜蓿、苇状羊茅、多年生黑麦草这4种野生牧草种子进行发芽试验,通过温度、NaCl溶液、KNO3溶液、浓H2SO4溶液、H2O2溶液等不同方法对这4种草种进行处理,对提高野生牧草种子的发芽方法进行探讨。结果表明,不同处理方法对发芽率的影响均达到显著水平。     

高校环保社团的作用

正"每个人都是一颗绿色的种子,我们想搬去种子头顶的砖石,通过环境教育让绿色的种子更加开阔地认识外面的世界,让绿色的种子更好地生根发芽、茁壮成长。""每个人都是一颗绿色的种子,我们想搬去种子头顶的砖石,通过环境教育让绿色的种子更加开阔地认识外面的世界,让绿色的种子更好地生根发芽、茁壮成长。"同济大学绿色之路协会环境教育组组长刘子鹏这样介绍他们的愿景。     

重金属联合毒性对植物种子萌发影响的实验研究

重金属具有长期性和滞后性,它能抑制植物的生长,并且富集在植物体内,人类作为食物链的顶端最终会摄入体内,进而对人类健康造成危害。探究联合重金属毒性作用对植物种子萌发的影响。分别配置5种不同浓度梯度的铬和镉重金属实验溶液,培养7 d后观察小白菜种子的发芽率、发芽势、根长、芽长情况,同时设置3个平行实验进行对照,记录培养皿中种子的发芽个数,最后测量植物芽及根的长度,通过绘制曲线来说明种子的生长趋势,讨论不同浓度重金属溶液组合对种子萌发的影响。实验表明,当Cd(≤30 mg/L)+Cr时,重金属对小白菜种子萌发有轻微的促进作用;Cd浓度大于30 mg/L后,开始出现抑制的效果。随着重金属溶液浓度的增加,会一直对种子起到抑制的影响,曲线显现出下滑趋势。     

音频电流种子处理机

音频电流种子处理机主要由音频电压发生器、联接电缆、电极板和浸种容器组成。使用时将浸润的农作物种子放置在电极板间 ,由于交变电流的生化作用 ,增强了种子的活力 ,有利于种子发芽生长 ,提高了出苗率 ,增强了抗病害能力。同时 ,该装置效率高、能耗小、使用简便、成本低 ,适于广泛推广应用。 (ＺＬ 992 0 5999.2 )音频电流种子处理机     

壳聚糖对小麦发芽及生根效应的研究

利用壳聚糖浸泡小麦种子,通过考察小麦的出芽率、发芽指数、活力指数、生根数量和根的长度等各项指标的变化,探讨壳聚糖对小麦发芽和生根生理效应的影响.结果表明,当pH值6.5、壳聚糖浓度为4-6mg/mL时能显著提高小麦种子活力,促进幼苗生长;当壳聚糖浓度低于8mg/mL时,小麦的出芽率、发芽指数、活力指数随壳聚糖处理浓度的增大而明显提高;当壳聚糖浓度为4mg/mL、浸泡时间为10h时,小麦种子生根效应最为明显.     

人工栽培棕树的方法

一、采种和选种棕籽是棕树的果实,一般在立冬后即每年的11月或12月成熟,呈灰黄色。当种子呈黑褐色时,便可采种。采种时应选择树杆粗壮、棕节紧密、果实饱满的棕树采种。采回的棕籽应用清水或木灰水浸泡1～2天,搓去果皮,捞出种子,选择籽粒饱满的种子,去掉嫩子、扁子、虫蛀子,阴干贮藏备翌年播种用。在收藏期应注意勿使种子发烧、生霉变质,以免影响种子发芽。     

冬播包衣种子

冬播包衣种子由种子和保护层构成,可在北方秋收整地后播下,到第二年春天,种子外层保护层降解,种子即可发芽。本种子从而变春播为冬播,对于保护土壤墒情,缓解春耕作业压力具有重要的作用。(ＺＬ972192093)冬播包衣种子...     

继往开来 千乡万村环保科普再放光芒

2007年首次“大学生志愿者千乡万村环保科普行动”已在农村播下了环保科普的种子，2008年，学会在环保部、中国科协的大力支持下继往开来，在原来的基础上再次多样化宣传，并争取多元化支持扩大影响，让环保科普种子生根发芽结果。     

推进环境友好创建 普及可持续发展教育

创建活动像一颗颗蒲公英的种子,正在城市各个领域扎根发芽,向公众传播着绿色环保理念,生态文明的时代风尚。     

迎阳报春种子萌发特性研究

通过种子萌发试验,研究了光照、温度、赤霉素对迎阳报春种子萌发的影响,同时对其种子形态进行了观测.结果表明,迎阳报春成熟种子为黄褐色,呈不规则卵圆形或多面形,种子细小,千粒重为89.52±0.25mg.种子萌发的适宜温度为20℃,对光敏感,光照条件下萌发率较高,萌发进程较快;种子经赤霉素处理后,萌发持续时间缩短,但对种子最终发芽率、发芽势影响不显著.     

柳叶蜡梅化感作用初探

以大豆、玉米作为受体,通过对种子萌发指标和幼苗生长量的测定,探讨柳叶蜡梅叶片水浸提液的化感作用.结果表明,不同浓度的柳叶蜡梅水浸提液对两种受体的种子萌发和幼苗生长量均有不同程度的抑制作用,相对电导率和丙二醛含量增加.因此,柳叶蜡梅对大豆、玉米均有化感抑制作用.     

柳叶蜡梅化感作用初探

以大豆、玉米作为受体，通过对种子萌发指标和幼苗生长量的测定，探讨柳叶蜡梅叶片水浸提液的化感作用。结果表明，不同浓度的柳叶蜡梅水浸提液对两种受体的种子萌发和幼苗生长量均有不同程度的抑制作用，相对电导率和丙二醛含量增加。因此，柳叶蜡梅对大豆、玉米均有化感抑制作用。     

Seed bank composition of open and overgrown calcareous grassland soils--a case study from Southern Belgium

The success of calcareous grassland recreation following abandonment depends to a large extent on the composition of the soil seed bank. We studied the species richness and composition of the seed bank along a chronosequence from well-developed calcareous grassland to scrub and forest vegetation, which had developed on calcareous grassland over the last 225 years. The seed bank density was highest in the calcareous grassland soils (930 seeds/m(2)). However, the seed bank was mainly composed of rather common species of nutrient poor grassland, which were poorly represented in the surface vegetation. There were no significant differences in soil seed bank density and species composition between the calcareous grassland and scrub vegetation that was less than 15 years old, largely because several grassland species had persisted in the scrub vegetation and were therefore able to replenish the soil seed bank. In contrast seed density and species richness declined significantly after 40 years of grassland abandonment. Indeed, forest soils had the lowest seed densities (214 seeds/m(2)) with only a few grassland species represented. This reflects the lack of grassland species in the field layer of the forest, and, therefore, the lack of seed production and seed bank replenishment. It is clear that recreation of calcareous grassland on long abandoned sites cannot rely on germination of target species from the seed bank alone. Even in the calcareous grassland soil, seeds of target species are not abundant as the majority produces transient seeds, which decay rapidly if they do not germinate immediately. Successful grassland recreation on such sites therefore may require seeds of target species to be introduced artificially (e.g. as seed mixtures, green hay, etc.). Alternatively, reinstatement of traditional practices, such as grazing or mowing, will increase the natural dispersal potential of these species, allowing population reestablishment in the long term.     

大庆油田废钻井液对农作物的影响

为了阐明废钻井液对农作物的生物效应，以大庆油田典型的水基废钻井坡进行了玉米、大豆种子发芽率试验及大豆盆栽试验。试验结果表明：各浓度组玉米、大豆种子发芽率均在93％以上，废钻井液未对种子幼芽产生毒害作用；对盆栽大豆籽实中金属及有机污染指标未造成影响；对大豆中营养指标─—蛋白质含量有增加的趋势，其淀粉含量有显著增加效应，脂肪含量无影响；对大豆株高增效明显，相对平均增高21．03％，各浓度组千粒重无明显区别。     

Weed seed viability in composted beef cattle feedlot manure

Manure composting has gained increased acceptance by the beef cattle (Bos taurus) feedlot industry in southern Alberta, Canada. Unlike fresh manure, compost is often promoted as being "weed-free." Studies were conducted with five weed species in 1997 and thirteen in 1999 to examine the effect of feedlot manure composting on weed seed viability. Weed seeds were buried in open-air compost windrows and recovered at various times during the thermophilic phase of composting. Windrow temperature and water contents were also measured. Germinability was zero for all composted weed seeds at all sampling times in 1997. However, some seeds remained viable (positive tetrazolium test denoting respiration) on Day 70. In 1999, only one of the thirteen species retained germinability on Day 21 and only two species had respiring seeds on Day 42. Time-viability relationships during composting were defined by exponential decay models. Lethal temperatures to eliminate viability was species-dependent. In 1999, four weed species were killed in the initial 7 d of composting at a lethal temperature of 39 degrees C while temperatures of > 60 degrees C were required for two species. Regression analysis on weed seed viability versus windrow temperature resulted in significant R2 values, which showed that only 17 to 29% of the variation in viability was accounted for by temperature. The lack of definitive relationships between temperature and weed seed viability demonstrated that factors other than temperature may play a role in eliminating weed seeds during composting.     

Germinable Soil Seed Banks and the Restoration Potential of Abandoned Cropland on the Chinese Hilly-Gullied Loess Plateau

Poor vegetation cover is generally considered to be a major factor causing soil erosion on the Loess Plateau in China. It has been argued that tree planting restoration is ineffective, and natural re-vegetation is an alternative ecological solution for restoring abandoned cropland and controlling soil erosion. The aims of this study were to investigate the characteristics of soil seed banks and to assess the natural restoration potential of abandoned cropland in the hilly-gullied Loess Plateau. The soil seed bank was identified by the germination method with the soil samples, which were collected at four sampling times (April, August, and October 2005 and August 2006) from 12 plots abandoned 3–30 years prior to sampling. The seed bank densities of all of the samples in the 0–10 cm soil layer varied from 1,067 ± 225 to 14,967 ± 1,606 seeds m⁻². Fifty-one species (24 annual and 27 perennial species) belonging to 18 families were identified, and 39% of these species belonged to the families Compositae and Gramineae. The pioneer species Artemisia scoparia dominated the seed bank, with an average seed density of 3,722 seeds m⁻², and accounted for 74.4% of the seeds in the bank. The local dominant species (such as Lespedeza davurica, Artemisia gmelinii, Bothriochloa ischaemun and Stipa bungeana) of the later succession stages also existed at densities varying from 17 to 1, 383 seeds m⁻². The combination of soil seed bank characteristics, reproductive traits of the species, the specific landscape conditions indicates that the potential to restoring the abandoned croplands in the hilly-gullied Loess Plateau via natural re-vegetation could be substantial.     

壳聚糖对小麦期叶中营养物质含量的影响

在不同壳聚糖浓度和时间条件下对小麦种子进行处理,通过小麦萌发后期叶中游离氨基酸、蛋白质、叶绿素和可溶性糖含量的变化,从而得出壳聚糖处理小麦种子的最佳条件为:浓度8g/L、浸种时间10h,其结果将对小麦生产提供理论基础.     

Ecological Impacts of Revegetation and Management Practices of Ski Slopes in Northern Finland

Outdoor recreation and nature-based tourism represent an increasingly intensive form of land use that has considerable impacts on native ecosystems. The aim of this paper is to investigate how revegetation and management of ski runs influence soil nutrients, vegetation characteristics, and the possible invasion of nonnative plant species used in revegetation into native ecosystems. A soil and vegetation survey at ski runs and nearby forests, and a factorial experiment simulating ski run construction and management (factors: soil removal, fertilization, and seed sowing) were conducted at Ruka ski resort, in northern Finland, during 2003–2008. According to the survey, management practices had caused considerable changes in the vegetation structure and increased soil nutrient concentrations, pH, and conductivity on the ski runs relative to nearby forests. Seed mixture species sown during the revegetation of ski runs had not spread to adjacent forests. The experimental study showed that the germination of seed mixture species was favored by treatments simulating the management of ski runs, but none of them could eventually establish in the study forest. As nutrient leaching causes both environmental deterioration and changes in vegetation structure, it may eventually pose a greater environmental risk than the spread of seed mixture species alone. Machine grading and fertilization, which have the most drastic effects on soils and vegetation, should, therefore, be minimized when constructing and managing ski runs.     

Effects of Three Fire-Suppressant Foams on the Germination and Physiological Responses of Plants

Suppressant foams used to fight forest fires may leave residual effects on surviving biota that managers need to consider prior to using them. We examined how three fire-suppressant foams (FSFs) (Forexpan S, Phos-Chek-WD881, and Silv-ex) affected seed germination and physiological responses of three plant species. Exposure to FSFs, whether in diluted concentrations or those typical in the field, reduced final germination percentages of seeds grown in petri dishes and within growth chambers. However, the FSFs did not cause total germination failure in any treatment. Inhibition of germination increased with longer exposure times, but only to diluted FSF solutions. Unlike in the laboratory experiments, none of the three FSFs affected seedling emergence when tested in field conditions. Further, we found no evidence of long-term phytotoxic effects on antioxidant enzyme activity nor chlorophyll content of the plant saplings. Therefore, although the three FSFs showed evidence of phytotoxicity to plants in laboratory tests, their actual impact on terrestrial ecosystems may be minimal. We suggest that the benefits of using these FSFs to protect plants in threatened forest ecosystems outweigh their minor risks.     

川牛膝种子保存技术初探

对川牛膝种子开展室温常规贮藏、室温湿沙贮藏、室温超干燥贮藏、4℃低温贮藏、冷冻贮藏等5种贮藏试验,结果表明：①室温湿沙贮藏是川牛膝种子短期保存的最优方法,能显著提高种子发芽率,其值较常规保存高14.5％;其次为4℃低温贮藏.②冷冻贮藏是川牛膝种子长期保存的最佳方法,保存3年后当其他保存方式的种子寿命几乎丧失时,其生活力及发芽率仍保持在较高水平,分别为60.3％和49.9％;其次为超干燥贮藏,种子生活力和发芽率分别为51.3％和41.2％.