The variation and plasticity of leaf morphology play a pivotal role in the response to environmental changes for plant individuals.Discovering the large-scale pattern of such variation can reveal plants’general adaptive strategies.We analysed leaf morphology of three widespread woody species in the northern hemisphere using specimen data from the iDigBio and GBIF databases,to investigate the variations in the individual mean traits,in the inter-and intra-individual variability of traits,and in the allometry between traits,along climatic gradients.We found that larger and wider leaves were associated with warmer,wetter and low-sunlight habitats,while smaller but wider leaves are linked to higher wind speed,indicating the response of leaf morphology to multiple climate stresses.The inter-individual variation in leaf area was smaller in colder and windier conditions,suggesting the trait convergence among individuals under environmental filtering,while the intra-individual variation in leaf relative width(RW)was smaller in warmer habitats,indicating the similar growth optimum of leaves within one individual in more favourable conditions.Finally,the allometric exponent between leaf length(X-axis)and width(Y-axis)became greater under lower solar radiation and higher wind speed,while the squared correlation coefficient(r^(2))indicating phenotypic integration showed a decoupling trend under colder conditions,indicating that climate affected the variation tendency of leaf RW during leaf enlargement.These results reveal the common patterns of leaf morphology responding to climate variation spatially and underscore the necessity to consider inter-and intra-individual variability when examining plant responses to environmental changes.
小麦旗叶是进行光合作用的主要功能叶,对产量有着重要贡献。为了解小麦旗叶形态的遗传机制,挖掘旗叶形态相关性状的候选基因,本研究采用300份小麦品种(系),结合90K SNP基因芯片对5种环境下正常灌溉(NI)和干旱胁迫(DS)条件下的旗叶长、宽、面积进行全基因组关联分析。结果表明,旗叶长、宽、面积在2种水分处理下表现出显著差异(P<0.05),在不同的环境下表现出丰富的表型变异,变异系数为0.07-0.23。全基因组关联分析(genome-wide association study,GWAS)结果显示,共检测到37个与旗叶长、宽、面积显著相关的稳定遗传位点,分布于1D、2A、2B、3A、3D、4A、5A、5B、6A、6B、7A、7B染色体上,单个SNP位点可解释遗传变异为3.70%-9.05%,其中正常灌溉下检测到22个稳定遗传位点,干旱胁迫下检测到15个稳定遗传位点。2种处理下共同检测到的稳定遗传位点有8个,位于2B、3A、5A、6A、7A、7B染色体上。在2B、3A、6A、7A染色体上检测到5个同时与多个性状相关联的稳定遗传位点。对稳定遗传且贡献率较大的标记处进行单倍型分析,发现与旗叶长显著相关的Kukri_c1406_275(R^(2)=9.05%)标记存在FLL-Hap1、FLL-Hap2和FLL-Hap3三种单倍型,与旗叶面积显著相关的wsnp_bq170165A_Ta_1_1(R^(2)=7.88%)标记同样存在FLA-Hap1、FLA-Hap2和FLA-Hap3三种单倍型。结合表型分析,在300份冬小麦品种(系)中含有FLL-Hap1(出现频率为77.78%)或FLL-Hap2(18.89%)单倍型品种(系)的旗叶长显著高于含有FLL-Hap3(3.33%)单倍型品种(系)的旗叶长,含有FLA-Hap1(48.19%)单倍型品种(系)的旗叶面积显著高于含有FLA-Hap2(30.80%)或FLA-Hap3(21.01%)单倍型品种(系)的旗叶面积(P<0.05)。不同单倍型在不同冬小麦品种(系)中分布不同,单倍型FLL-Hap1在国外品种(系)占比较大,单倍型FLL-Hap2、FLL-Hap3分别在北部冬麦区和西南冬麦区占比较大。单倍型FLA-Hap1和FLA-Hap2分别在西南冬麦区和北部冬
