两种独行菜种子萌发对不同浓度NaCl胁迫的响应     

李天永  严子柱  姜生秀 《草地学报》2021,29(1):88-94

为探究腺独行菜（Lepidium apetalum Willd）和宽叶独行菜（Lepidium latifolium L.var.affine C.A.mey）种子萌发耐盐性特征，用玻璃培养皿采用暗发芽的方法，在恒温25℃种子培养箱中进行发芽试验，测定不同NaCl浓度（0，50，100，150，200，250，300 mmol·L^-1）胁迫下两种独行菜种子的发芽率、发芽势、日均发芽率、日相对发芽率和种子胚芽、胚根的长度。结果表明：在同等盐胁迫下，腺独行菜种子的发芽率、发芽势等各项指标均显著大于宽叶独行菜种子的。在不同盐胁迫下，随NaCl浓度增大，腺独行菜种子发芽率呈先增大后减小的特征，发芽势呈持续下降趋势；宽叶独行菜种子的发芽率和发芽势均呈显著下降特征，且NaCl浓度达到150 mmol·L^-1后，失去发芽能力；种子胚芽、胚根生长始终表现为腺独行菜优于宽叶独行菜。  相似文献   

Roads limit of seed dispersal and seedling recruitment of Quercus chenii in an urban hillside forest     

《Urban Forestry & Urban Greening》2018

Paved roads in urban forests cause forest fragmentation and thus reduce animal populations, threaten dispersal and recruitment of animal-dispersed plants. Here, we tracked animal-mediated seed dispersal of Quercus chenii in the urban forest centre and near roadsides to test the effect of paved roads on seed dispersal and recruitment. We conducted experiments in a forest patch in urban areas of Wuhan, China. The forest was dominated by the focal tree species and separated by paved roads. Only two potential seed dispersal animals, one rodent (Niviventer confucianus) and one jay (Garrulus glandarius) were observed in this stand. Seeds were removed farther but not as fast in the forest centre compared to roadsides, while no differences of seed fate, dispersal direction, and seedling establishment were detected between the forest centre and roadsides, indicating the thick vegetation along roadsides provided feeding shelters for small animals. However, when compared with primary forests containing more seed dispersers, seed removal rate in this urban forest fragment was much slower in both forest centre and roadside. Furthermore, due to road barriers, seeds were seldom moved across the paved road and remained in the fragmented stand, reflecting a limited function of seed dispersers. These results suggested paved roads isolated forests into small “islands” and weakened the ecological function of seed dispersers by impeding long distance seed dispersal. Reintroducing dispersers and building wildlife corridors would be impactful ways to restore urban forest patches.  相似文献   

桃种子的休眠与萌发研究──种皮的调控作用     

陶俊  陈云志 《果树学报》1996,(4)

用桃品种秋香蜜去核壳种子，探索了种皮控制休眠与萌发的效应及作用机制。结果表明：①桃种子剥除种皮，休眠可被解除，出苗率与有皮种子经ＧＡｓ２００ｍｇ·ｌ￣（－１）浸种２４ｈ相近；种皮抑制萌发的效应与ＡＢＡ５ｍｇ·ｌ￣（－１）浸渍去皮种子２４ｈ相当。②桃新鲜种子内ＡＢＡ主要存在于种皮中，ＧＡ３主要存在于胚和子叶中，剥除种皮即人为地改变种子内ＧＡ＿３／ＡＢＡ值，有利于种子由休眠向萌发方向转化。③桃种皮对种子内过氧化物酶活性具强烈抑制作用；去皮种子的酶活性随ＧＡ３处理而增强，随ＡＢＡ处理而被抑制。④桃种皮无透水性障碍，种皮对种子的吸水总量虽有一定限制，但不影响种子萌芽。  相似文献   

Biological control of Rhizoctonia sp. root rot of Casuarina equisetifolia seedlings by Frankia spp. strains   总被引：1，自引：0，他引：1  

S. Gopinathan 《Biology and Fertility of Soils》1995,20(4):221-225

Seventy Frankia spp. strains (nodulating N₂-fixing actinomycetes) were isolated from root nodules of Casuarina equisetifolia from different localities of Tamil Nadu state, India. From these, four strains (UMCe12, UMCe23, UMCe35, and UMce55) were selected. Their potential use as biological control agents for Rhizoctonia solani root rot disease of C. equisetifolia seedlings and their relative efficiency in nodule production were investigated. Between the two inoculum broadcast systems tested, seed-coating with Frankia spp. cell suspension was superior to the soil application of cells as sand-vermiculite-basal ammonium propionate inoculum. UMCe12 was the promising strain, offering the highest level of disease protection (81.1%) and nodule production (88.1%) in the R. solani-infested soil, followed by UMCe23 (60.3 and 65.5% of disease protection and nodule production, respectively), UMCe55 (53.5 and 58.2%), and UMCe35 (45.4 and 44.5%). Further, a significant positive correlation was observed between the dose of Frankia spp. and efficiency in both disease control and nodule production.  相似文献   

High Protein Soybean Performance Under Field Conditions     

B. L. Ma    S. Leibovitch    H. D. Voldeng  D. L. Smith 《Journal of Agronomy and Crop Science》1993,170(5):327-329

An early maturing soybean [ Glycine max (L.) Merr.] cultivar has been developed with substantially higher seed protein concentration than previously available cultivars. The objectives of this study were to evaluate the performance of the high protein line under field conditions in Eastern Canada, and to investigate the interrelationships between protein and oil concentrations, seed weight and yield. A field experiment, including the high protein line OT89-16 and its recurrent backcross parent Maple Arrow grown side by side, was conducted at McGill University, during 1990 and 1991. The protein concentration of OT89-16 was 17 % greater than that of Maple Arrow for both years. However, the protein yield of OT89-16 was not significantly increased, the oil content was 19 to 23 % lower, and oil yield per ha was over 30 % lower than those of Maple Arrow. The lower yield of OT89-16 was closely associated with its lighter seeds. Further efforts to improve the high protein line should attempt to maintain the same high protein levels but achieve yield equal to that of the parent line through selection for heavier seeds.  相似文献   

不同树种采用种基盘造林时出苗情况初报   总被引：1，自引：0，他引：1  

武应霞  汪泽军  林春阳 《河南林业科技》2003,23(3):3-4

在太行山南麓三种不同的立地条件下,采用种基块造林方法,对8个拟选造林树种进行了出苗试验研究。结果表明:臭椿、胡枝子、80℃温水处理的金合欢适应性较强,它们的出苗率分别为91％、67.5％、52％。  相似文献   

松嫩平原蒙古蒿无性系种群结构的研究   总被引：7，自引：1，他引：6  

杨允菲  王德利  张宝田  李建东 《草业学报》2003,12(3):8-15

蒙古蒿为根茎型多年生草本菊科植物。在生长季后期，分株在根颈处产生两种芽越冬，翌年根颈芽和根茎顶端芽均可发育为分株。通过对蒙古蒿的研究，创建了按根茎芽的繁殖世代数划分根茎型多年生草本菊科植物种群无性系分株的年龄及鉴别方法，以及用不同世代成员的数量配置来分析草本植物种群分株的年龄结构。龄级的划分标准是；由根茎顶端芽形成的分株为营养繁殖一代，作为1供级；1龄级分株死亡后，由根颈芽第1次萌生向上生长的分株为营养繁殖二代，作为2龄级；2龄级分株死亡后，由根颈芽第2次萌生向上生长的分株为营养繁殖三代，作为3龄级。鉴别时，如果分株顶端受损发生在根颈区以上的任何分枝均仍为原龄级，而不为下一个世代的龄级；如果根颈区有2个以上的芽同时萌生向上生长成株，则划分为同龄级。蒙古蒿的根茎芽最多可营养繁殖3个世代，根颈的生活年限最多为4年。在松嫩平原割草场，蒙古蒿种群进入开花期以后，种群由营养分株和生殖分株组成。各分株组分均有3个龄级，其数量和生物量均呈增长型年龄结构。生殖分株的生产力是营养分株的4—7倍。蒙古蒿芽库的潜在种群呈增长型年龄结构。分株根颈的繁殖潜力以1龄级最大，随着龄级的增加依次减弱。如果环境条件有利，蒙古蒿种群将以每年10cm的速度扩展种群的生态位空间。  相似文献   

柠条种子象甲研究初报     

冀卫荣  谢映平 《山西农业大学学报(自然科学版)》1993,13(4):313-314

柠条种子象甲(Apion sp.)在晋西北地区柠条林内发生严重,占总虫量的66.7～81.3%是当地柠条种子的主要害虫。本文描述了其形态学特征,生活史和生物学特性,并对柠条林内的虫口密度和寄生性天敌做了抽样调查。  相似文献   

云南板栗实生选种     

邵则夏  陆斌  郑子英  徐跃  李顺荣 《西部林业科学》1995,(4)

本文论述了云南板栗（ＣａｓｔａｎｅａｍｏｌｌｉｓｓｉｍａＢｌ．）的地理分布，生产中存在的问题以及实生选种的目的意义。对入选的３６个优株进行评比试验。经子代测定，选出了１７个优系，描述了特征特性，并建立了采穗圃，为云南板栗生产良种化、产业化和商品化提供了可靠的种质资源。  相似文献   

防治甘蓝种带病菌的药剂筛选     

李明 《山西农业科学》1994,22(4):40-42

１９９２年进行了防治甘蓝种带病菌的药剂筛选工作，结果表明，当使用的土霉素含量为０．１％，百菌清有效含量为３％的药液（又称种衣剂）处理种子时，对甘蓝种子表面携带之真菌、细菌的防效分别达到８０％和９３％，种子发芽不受影响。  相似文献