Ecological and Genetic Implications of Foliar Polymorphism inMetrosideros polymorphaGaud. (Myrtaceae) in a Habitat Matrix on Mauna Loa, Hawaii
Ecological and Genetic Implications of Foliar Polymorphism inMetrosideros polymorphaGaud. (Myrtaceae) in a Habitat Matrix on Mauna Loa, Hawaii
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地黄叶多态性的生态和遗传意义。
DOI：
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发表时间：
1997
期刊：
影响因子：
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通讯作者：
D. Mueller‐Dombois
中科院分区：
文献类型：
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作者：
K. Kitayama;R. Pattison;S. Cordell;D. Webb;D. Mueller‐Dombois
Metrosideros polymorpha的无毛和短柔毛叶表型共域发生在莫纳罗亚山，夏威夷。这种共存已被早期的工作者提出，代表不同的基因型，每一种基因型产生具有同质叶表型的后代。我们重新研究了在相同的共同花园条件下生长时，来自相同父母的兄弟姐妹在表型上的差异程度。种子从亲本树收集在两个基质年龄的矩阵（114-140年相对于约。1200-3200岁）在五个海拔从低地（100米）到树线（2470米）的莫纳罗亚山。在1200 m的相同环境条件下播种和生长种子。在田间亲本种群中，两种类型在两种基质上随着降雨量的减少（<2000 mm）而收敛成短柔毛形式，并且在降雨量充足的情况下随着土壤年龄的增加而收敛成无毛形式。4岁的幼苗从青春期的父母总是表示无毛和青春期的表型，所有的海拔高度，除了年轻的1980米的网站的两个基板年龄。来自无毛亲本的幼苗倾向于只表达无毛表型，除了年轻的1280-m站点。总体而言，所有人口的年轻熔岩流（无毛和青春期的个人结合，如果共存）可以产生后代的两种表型，除了在1980米。同一亲本的同胞中，近轴叶片表面的角质层厚度与短柔毛的大小呈正相关（P=0.05），无毛个体的平均角质层厚度为6.0 μm，多数短柔毛个体的平均角质层厚度为15.7 μm。较大幅度的短柔毛与更多的负渗透势在膨压损失点，并与更大的最大CO2同化率在光饱和点。这种生理和解剖的多态性，加上空间和时间上不同的选择力，似乎导致海拔和演替patternedM。在莫纳罗亚山湿坡上的多形种群。
Glabrous and pubescent foliar phenotypes ofMetrosideros polymorphaoccur sympatrically on Mauna Loa, Hawaii. This coexistence has been suggested, by earlier workers, to represent distinct genotypes, each of which produces progenies with a homogenous foliar phenotype. We re-examined the question of to what extent siblings from the same parents varied in phenotype when grown under the same common-garden conditions. Seeds were collected from parental trees in a matrix of two substrate ages (114–140 yrvs.approx. 1200–3200 yr old) at five elevations from lowland (100 m) to treeline (2470 m) on Mauna Loa. Seeds were sown and grown under identical environmental conditions at 1200 m. In field parental populations, two forms converged into pubescent forms with decreasing rainfall (<2000 mm) on both substrates, and into glabrous forms with increasing soil age where rainfall was ample. The 4-yr old seedlings from pubescent parents invariably expressed both glabrous and pubescent phenotypes for all altitudes and for both substrate ages except for the young 1980-m site. The seedlings from glabrous parents tended to express only the glabrous phenotypes except for the young 1280-m site. Overall, all populations on the young lava flow (glabrous and pubescent individuals combined if coexisting) could produce progenies of both phenotypes except at 1980 m. Cuticle thickness on the adaxial lamina surface was positively correlated with the magnitude of pubescence (P=0.05) among siblings from the same parents, ranging from a mean cuticle thickness of 6.0 μm for glabrous to 15.7 μm for the most pubescent individuals. Greater magnitudes of pubescence were associated with more negative osmotic potentials at turgor loss point, and with greater maximum CO2assimilation rates at the point of light saturation. This physiological and anatomical polymorphism, together with spatially and temporally varying selective forces, appears to result in elevationally and successionally patternedM. polymorphapopulations on the wet slope of Mauna Loa.