摘要
为探究老芒麦离区形态特征和影响落粒的关键因素,以1份高落粒种质和1份低落粒种质为研究对象,两份材料各自达到乳熟期开始分批采集样品,从离区形态特征、水解酶活性、动态落粒率及生理特性方面对两份种质及两种脱落类型进行了比较分析,进而明确高落粒与低落粒材料在落粒性上的差异以及种柄离区和小穗柄离区的差异。结果表明:1)高落粒材料的离区发育较低落粒材料早,且离区内陷较明显。种柄离区发育较小穗柄离区早,且离区更明显。观察脱落后的离区断裂面发现,离区存在环状结构。2)水解酶活性在乳熟后各时期存在差异,种子成熟后期酶活性普遍较高。高落粒材料的酶活性高于低落粒材料,种柄酶活性高于小穗柄酶活性,表明种柄脱落在落粒过程中占主导位置。3)种子成熟过程中,落粒率逐渐增加,高落粒种质的落粒率始终高于低落粒种质,且高落粒种质乳熟后第16天开始落粒率迅速增加。4)种子成熟过程中,落粒率与含水量、电导率及可溶性糖含量呈极显著(P<0.01)负相关,而与酶活性、发芽率及淀粉含量呈显著(P<0.05)或极显著(P<0.01)正相关,表明生理物质对老芒麦落粒具有一定的调控作用。因此,综合以上生理指标选择乳熟后第16天为老芒麦的最适收获期,该时期老芒麦种子已具有较高的活力,且能避免种子脱落的高峰期。
This study examined contrasting shattering-prone and shattering-resistant germplasm lines of Elymus sibiricus in order to explore the morphological characteristics of the abscission zone and identify key factors affecting shattering.Samples were collected in batches from the two germplasm lines at intervals from milk stage until the maturity stage of grain development.The two germplasm lines with their contrasting shattering behavior were compared and morphological characteristics of the abscission zone,enzyme activity,dynamic shattering rate and physiological traits were evaluated.In this way,the differences in shattering-related traits between shattering-prone and shattering-resistant germplasm could be identified,as well as differences in the seedstalk and the spikelet stalk abscission zone.It was found that:1)The abscission zone development of the shattering-prone germplasm was earlier than that of shattering-resistant germplasm,and the distinction was obvious.The development of the seed-stalk abscission zone was earlier and more obvious than the spikelet stalk abscission zone.Observation of the fracture surface of the abscission zone after shedding revealed that there was a ring structure in the abscission zone.2)The hydrolase activity differed at each grain maturity stage after the milk stage,and the enzyme activity was generally higher in the later stages of seed maturity.The enzyme activity of shattering-prone germplasm was higher than that of shattering-resistant material,and the enzyme activity of the seedstalk was higher than that of the spikelet stalk,indicating that seedstalk shedding was dominant in the shattering process.3)As the seed ripened,the incidence of shattering gradually increased.At any given development stage,the shattering rate of shattering-prone germplasm was always higher than that of shattering-resistant germplasm,and the shattering rate of shattering-prone germplasm accelerated from the 16th day after the milk stage of grain development.4)During the process of seed maturation,the s
作者
吴瑞
刘文辉
张永超
刘敏洁
WU Rui;LIU Wen-hui;ZHANG Yong-chao;LIU Min-jie(Key Laboratory of Utilizing Excellent Forage Germplasm Resources in Qinghai-Tibet Plateau,Academy of Animal Husbandry and Veterinary Sciences,Qinghai University,Xining 810016,China)
出处
《草业学报》
CSCD
北大核心
2022年第4期81-92,共12页
Acta Prataculturae Sinica
基金
青海省科技厅重点实验室发展专项(2020-ZJ-Y03)
国家现代农业产业技术体系(CARS-34)资助。
关键词
落粒
离区
生理指标
最适收获期
shattering
abscission zone
physiological index
optimal harvesting time
