节节麦小穗上不同粒位种子萌发对环境因子的响应  

Response of seed germination at different grain positions on spikelet of Aegilops tauschii to environmental factors

作　　者：于海燕 李华通 崔海兰[1] 陈景超[1] 李香菊[1] YU Haiyan;LI Huatong;CUI Hailan;CHEN Jingchao;LI Xiangju(Institute of Plant Protection,Chinese Academy of Agricultural Sciences,Beijing 100193,China)

机构地区：[1]中国农业科学院植物保护研究所,北京100193

出　　处：《植物保护》2021年第4期96-101,共6页Plant Protection

基　　金：国家重点研发计划(2016YFD0300701)。

摘　　要：为明确节节麦小穗上不同粒位种子萌发对环境因素的响应差异,采用培养皿法测定了小穗基部小花形成的第1粒种子(S1)和相邻上部位置小花形成的第2粒种子(S2)萌发对酸碱胁迫、盐胁迫和水分胁迫的响应。结果显示:S1和S2萌发均对pH要求不高,但在供试pH为3~10时,S2的萌发速率大于S1。与S1相比,S2萌发具有较强的耐盐性,在不同盐浓度下,S2发芽率相对较高,而S1的发芽率随着盐浓度的升高显著降低。此外,盐胁迫对S1和S2的萌发速率有一定影响,两者的萌发速率均随着盐浓度的升高而降低,但S2较S1萌发快。水分胁迫对节节麦S1和S2萌发均有抑制作用,但S2萌发对水分胁迫的耐受性显著高于S1,在渗透势为-1.28~-0.69 MPa时S1的发芽率达到最大发芽率的50%,而S2在渗透势为-1.75~-1.56 MPa时发芽率达到最大发芽率的50%。此外,S1和S2的萌发速率均随着渗透势的下降而降低,但S2的萌发速率大于S1。以上结果表明,节节麦种子萌发过程中第2粒位种子S2比第1粒位种子S1更具有耐受环境胁迫的能力。Experiments were conducted in petri dishes to determine the effects of seed positions in the spikelets of Aegilops tauschii,namely the seeds in positions S1(seeds produced in the basal florets)and S2(seeds produced in the second florets),on the differences of their germination responses to environmental factors,pH,salinity stress and water stress.The results showed that S1 and S2 could germinate under a wide range of pH values.However,the germination speed of S2 was higher than that of S1 when pH ranged from 3 to 10.Compared with S1,S2 exhibited higher tolerant ability to salinity stress.With the increase of NaCl concentration,the germination percentage of S1 gradually decreased,while that of S2 was relatively higher.Besides,salinity stress had a significant effect on the germination speeds of S1 and S2,and their germination speeds decreased with increasing concentration of NaCl;however,S2 germinated faster than S1.Water stress markedly inhibited the germinations of S1 and S2,yet S2 was more tolerant to water stress than S1.Germination rate reached 50%of the maximum germination percentage when the osmotic potential for S1 ranged from-1.28 MPa to-0.69 MPa,while that for S2 ranged from-1.75 MPa to-1.56 MPa.Additionally,although the germination speeds of S1 and S2 declined with decreasing osmotic potential,the germination speed of S2 was higher than that of S1.These results indicated that the germination of A.tauschii seeds S1 and S2 exhibited different responses to environmental stress.

关 键 词：杂草生物学 节节麦 种子萌发 环境胁迫 

分 类 号：S451[农业科学—植物保护]