草业学报2018，Vol.27Issue(3)：126-134,9.DOI:10.11686/cyxb2017193
野榆钱菠菜三种异型种子幼苗的生长特性
Investigation of growth characteristics of seedlings from three types of heteromorphic seeds of Atriplex aucheri
摘要
Abstract
Atriplex aucheri is an important wild forage germplasm resource in Xinjiang desert regions.It exhibits seed heteromorphism,with 3 types of seed produced:brown seeds (non-dormant),large black and small black seeds (dormant).Seeds from a single A.aucheri plant (grown from one particular seed type) were used as experimental material.The three types of seeds were cultivated under natural conditions,and comparative studies of germination phenology and growth characteristics of three types of seeds carried out.It was found that:1) The germination phenology of heteromorphic seeds were unsynchronized,and different types of seeds had different germination strategies.The germination of brown seeds was rapid with an emergence rate of up to 74.30％ within 3 days.The germination of the other two types was delayed with emergence rates of 6.58％ and 1.55％,after 21 and 17 days,respectively,for large and small black.2) The cotyledons of all three types of seeds were retained for an extended time during germination,but the retention time varied with the seed size.The smaller the seeds were,the shorter the cotyledon retention time.3) The cotyledon size,root length,and above-and below-ground biomass of brown seeds were all significantly greater than those of the two types of black seeds in the early growth stages,but as seedlings developed,the size differences between plants from different seed types decreased gradually.4) The seedlings from different types of seed displayed different biomass allocation strategies.Seedlings grown from brown seeds showed comparatively greater development of the above-ground organs,while the two types of black seeds prioritized below-ground development.Seed heterom0rphism therefore provides different seedling survival strategies (rapid establishment after occasional rain or stress tolerance in less favourable conditions).This seed heteromorphism is an important ecological adaptive mechanism for plants growing in the hash desert environment.This study provides novel insight into the ecological significance of seed heteromorphism in this desert environment and also provides a basis for a new theoretical theory of ecological bet-hedging.关键词
野榆钱菠菜/种子异型性/萌发物候/幼苗Key words
Atriplex aucheri/seed heteromorphism/germination phenology/seedling引用本文复制引用
马赫,魏岩,穆晨..野榆钱菠菜三种异型种子幼苗的生长特性[J].草业学报,2018,27(3):126-134,9.基金项目
国家自然科学基金项目(31560113,31360091)资助. （31560113,31360091）
