青海扁茎早熟禾形态特征与生物量对磷添加的响应  

Effects of phosphorous application on the morphological characteristics and biomass yield of Poa pratensis var.anceps’Qinghai’

作　　者：何克燕 王佳豪 张燕 宗嘉婷 孟思宇 段嘉蕾 魏小星[1] HE Keyan;WANG Jiahao;ZHANG Yan;ZONG Jiating;MENG Siyu;DUAN Jialei;WEI Xiaoxing(Qinghai Academy of Animal and Veterinary Science/Key Laboratory of Superior Forage Germplasm in the Qinghai-Tibetan Plateau,Xining 810016,Qinghai,China;College of Forestry,Gansu Agricultural University,Lanzhou 730070,Gansu,China)

机构地区：[1]青海大学畜牧兽医科学院/青海省青藏高原优良牧草种质资源利用重点实验室,青海西宁810016 [2]甘肃农业大学林学院,甘肃兰州730070

出　　处：《草业科学》2022年第11期2414-2423,共10页Pratacultural Science

基　　金：青海省应用基础研究(2020-ZJ-710);青海省创新平台(2021-ZJ-Y03);西部之光计划(2021-XBZG-12);青海省“高端创新人才计划”(2020-PYBJ-84);国家自然科学基金(31760711)。

摘　　要：磷添加可塑造植物的形态特征、促进植物生长发育,这对应用根茎型植物进行天然草地退化修复具有重要意义。青海扁茎早熟禾(Poa pratensis var.anceps‘Qinghai’)是高寒退化草地恢复的优选根茎型草种,但磷添加对其形态特征及生长发育的影响是否有利于退化草地的治理尚未可知。因此,本研究以青海扁茎早熟禾栽培草地为研究材料,通过3.6、7.2、10.8、14.4、18.0、21.6 kg·hm^(-2)6个磷素添加梯度,探讨磷添加对植株形态、生物量及生物量分配的影响。结果表明:1)磷添加对青海扁茎早熟禾植株的形态特征具有显著影响(P<0.05),植株的生物量随磷素的增加先增加后降低,施磷素10.8 kg·hm^(-2)时,形态指标与生物量表现较好。2)青海扁茎早熟禾株高、叶宽、叶长、叶面积及根分叉数是影响个体生物量的主要因子,对个体生物量的贡献率高达59%,地上器官对磷添加敏感,可塑性更强。因此,施磷素10.8 kg·hm^(-2)时,青海扁茎早熟禾的植株高度、叶片及根系的生长状况表现较好,总生物量最大,该施磷水平下植株具有较强的抗逆性,这对应用该草种进行退化草地恢复治理具有重要意义。Phosphorus application may affect the morphological characteristics of plants,promote their growth,and increase productivity.This has great importance for natural degraded grassland restoration using rhizomatous plants.Poa pratensis var.anceps’Qinghai’is one of the best rhizomatous grass species for degraded grassland restoration in alpine regions.However,it remains to be determined whether the effects of phosphorus addition on the morphological characteristics and growth of P.pratensis var.anceps’Qinghai’are beneficial to the management of degraded grassland.The primary goal of this study was to explore biomass yield and morphological characteristics after applying six different concentrations(3.6,7.2,10.8,14.4,18.0,and 21.6 kg·ha^(-1))of phosphorus fertilizer.We found that phosphorus addition had a significant effect on the morphological characteristics of P.pratensis var.anceps’Qinghai’.Plant biomass first increased and then decreased with increasing amounts of phosphorus addition,while morphological indices and biomass were best at 10.8 kg·ha^(-1).Plant height,leaf width,leaf length,leaf area,and root bifurcation were the main factors affecting the biomass of individual P.pratensis var.anceps’Qinghai’plants,and these factors contributed to 59%of individual biomass variation.Above-ground organs were sensitive to phosphorus addition and had stronger plasticity.Therefore,P.pratensis var.anceps’Qinghai’showed the greatest plant height,leaf and root growth,and total biomass at a phosphorus fertilizer concentration of 10.8 kg·ha^(-1).Thus,the plant had strong resistance to stress at this phosphorous level.This has great significance for the restoration and management of degraded grassland with this grass species.

关 键 词：青海扁茎早熟禾 磷 生物量 生物量分配 可塑性 可塑性指数 形态特征 

分 类 号：S543.9[农业科学—作物学]