干旱区生态环境知识资源中心(Arid): 红砂和霸王种子萌发对干旱与播深条件的响应

Arid

	红砂和霸王种子萌发对干旱与播深条件的响应
其他题名	Seed germination responses of Reaumuria soongorica and Zygophyllum xanthoxylum to drought stress and sowing depth
	曾彦军 1; 王彦荣 1; 庄光辉 2; 杨鬃山 2
来源期刊	生态学报
ISSN	1000-0933
出版年	2004
卷号	24 期号:8 页码:1629-1634
中文摘要	红砂(Reaumuria soongorica)和霸王(Zygophyllum xantho xylum)分别是我国西北干旱荒漠区重要的超旱生小灌木和灌木.试验室条件下,研究了两种灌木种子萌发对干旱胁迫(以PEG模拟干旱条件)和播深的响应.干旱胁迫设0、 -0.3、 -0.6、-0.9、-1.2、-1.5、-1.8、-2.1、-2.4、-2.7MPa共10个处理,播深设0、0 .3,0.5,1.0,1.5,2.0,3.0,4.0cm共8个处理.结果显示:模拟干旱条件下,供试种的发芽势(3d发芽率)皆从-0.3MPa起即开始显著下降(P<0.05) .发芽率红砂从-0 .9MPa渗透势、霸王从-0.6MPa开始显著降低;种子萌发的最低渗透势阈值红砂和霸王分别为-1.8MPa和-1.5MPa.干旱胁迫对种子胚芽生长有抑制作用,但轻度干旱可促进初生根生长,重度干旱胁迫抑制初生根生长.播深实验表明,红砂和霸王种子均为子叶出土发芽类型 .一般情况下,供试种随播深增加胚芽长度呈增加而初生根呈下降趋势,但霸王在播于土表时初生根生长受到抑制.实验室条件下,达到最大出苗率的播深红砂为0～0.5cm,霸王为0 ～2cm.在适宜条件下,红砂和霸王种子萌发的最低需水量分别为110%和90%,初始萌发时间分别为40h和48h.红砂种子发芽势低(28%)、萌发持续而分散;霸王种子发芽势高(87%) 、萌发整齐.讨论了两种种子发芽对干旱和播深的响应特征及其生态生物学意义.
英文摘要	Reaumuria soongorica and Zygophyllum xanthoxylum are very important ultra-xeromoph shrubs in the northwest arid desert region of China. Seeds of the two species were collected at maturity in the Alashan aria desert grassland of China in 2001 and kept at - 5 C until use. Responses of seed germination to simulated drought stress (germination paper moistened by PEG 6000 solution) and sowing depths were investigated in this study. The drought stress included 10 treatments ranging from 0 to - 2. 7MPa, and sowing depth comprised 8 treatments ranging from 0 to 4cm in sand soil medium. All tests were conducted at the Herbage Seed Testing Center, Ministry of Agriculture of China ( Lanzhou ) from December 2001 to May 2002. Each test was arranged in 4 replicates with 50 seeds for each replication. Results showed that germinative capacity (3d germination rate) of the test species declined significantly ( P<0. 05 ) as the osmotic potential decreased. Compared to control (0MPa ), final germination percentages started reducing ( P<0. 05 ) at - 0. 9MPa in R. soongorica and at - 0. 6MPa in Z. xanthoxylum. The lowest thresholds of osmotic potential for seed germination were - 1. 8MPa in R. soongorica and -1. 5MPa in Z. xanthoxylum. Both plumule and radical length of the test species were significantly ( P<10.05 ) reduced as the osmotic potential decreased, except that the radical length increased between OMPa and -0. 3MPa. This result indicated that slight drought stress can promote radical growth in these species. The sowing depth experiment indicated that both test species belong to an epigeal germination type. The maximum seedling emergence percentages were obtained in 0 - 0. 5cm sowing depths for R. soongorica and in 0 ~ 2cm for Z. xanthoxylum, showing that emergence of 2. xanthoxylum was more tolerant to the deeper sowing depth. Generally, the plumule length increased and radical length decreased as the sowing depth increased, except that the radical growth of Z. xanthoxylum was inhibited for surface sowing. This may have been because water uptake was limited on the surface for the large seed size of this species. The ratio of plumule and radical length showed a tendency to increase as the sowing depth increased, and this was more evident for Z. xanthoxylum at a sowing depth from 2 to 4cm. Under optimum conditions, germination characters for the test species showed that minimum water uptake rates for germination were 110% and 90%, and initial germination times were 4Oh and 48h for R. soongorica and Z. xanthoxylum, respectively. R. soongorica seeds showed a lower germination capacity and slower germination speed than those of Z. xanthoxylum. For instance, germination capacities were 28% for R. soongorica and 87% for Z. xanthoxylum. The ecological significance of the relationship between germination and germination conditions is discussed.
中文关键词	种子萌发 ; 干旱胁迫 ; 吸水率 ; 播种深度 ; 荒漠草地
英文关键词	seed germination drought stress water uptake rates sowing depth desert grassland
语种	中文
国家	中国
收录类别	CSCD
WOS类目	AGRONOMY
WOS研究方向	Agriculture
CSCD记录号	CSCD:1811516
来源机构	兰州大学
资源类型	期刊论文
条目标识符	http://119.78.100.177/qdio/handle/2XILL650/205371
作者单位	1.兰州大学草地农业科技学院甘肃草原生态研究所, 兰州, 甘肃 730020, 中国; 2.内蒙古阿拉善盟草原站, 巴彦浩特, 750360
推荐引用方式 GB/T 7714	曾彦军,王彦荣,庄光辉,等. 红砂和霸王种子萌发对干旱与播深条件的响应[J]. 兰州大学,2004,24(8):1629-1634.
APA	曾彦军,王彦荣,庄光辉,&杨鬃山.(2004).红砂和霸王种子萌发对干旱与播深条件的响应.生态学报,24(8),1629-1634.
MLA	曾彦军,et al."红砂和霸王种子萌发对干旱与播深条件的响应".生态学报 24.8(2004):1629-1634.