Host investment into symbiosis varies among genotypes of the legume Acmispon strigosus , but host sanctions are uniform
Host investment into symbiosis varies among genotypes of the legume Acmispon strigosus , but host sanctions are uniform
复制标题
豆科植物Acmispon strigosus的不同基因型对共生的宿主投入有所不同，但宿主的制裁是一致的。
DOI：
10.1111/nph.15378
复制
发表时间：
2018
期刊：
影响因子：
9.4
通讯作者：
Sachs, Joel L.
中科院分区：
文献类型：
--
作者：
Wendlandt, Camille E.;Regus, John U.;Gano-Cohen, Kelsey A.;Hollowell, Amanda C.;Quides, Kenjiro W.;Lyu, Jonathan Y.;Adinata, Eunice S.;Sachs, Joel L.
有效的宿主控制预示着无效共生体的灭绝，但它们在自然界中仍然广泛存在。我们检验了三个假设，以维持共生变异的根瘤菌，与一个本地豆科植物：配偶体之间的主机和共生体不匹配，使共生体的有效性与主机基因型;资源饱和，从而外部来源的营养放松主机控制;我们用三个共生效果不同的慢生根瘤菌菌株接种来自六个种群的Acmisson strigosus，同域寄主我们测量了零添加氮（N）和近生长饱和氮（N）施肥处理下单接种和共接种的宿主和共生体适合度的代理。我们研究了宿主控制的两个组成部分：在单接种和共接种过程中对根瘤大小的“宿主投资”，以及在共接种过程中对低效菌株的“宿主制裁”。在所有的寄主中，寄主制裁都是强有力的，但是在单接种和共接种实验中，来自不同种群的寄主株系在寄主投资的度量上存在显著差异，寄主投资的变化可以促进共生有效性的变化，并防止无效的Bradyrhizobium从自然种群中灭绝。
Efficient host control predicts the extirpation of ineffective symbionts, but they are nonetheless widespread in nature. We tested three hypotheses for the maintenance of symbiotic variation in rhizobia that associate with a native legume: partner mismatch between host and symbiont, such that symbiont effectiveness varies with host genotype; resource satiation, whereby extrinsic sources of nutrients relax host control; and variation in host control among host genotypes.We inoculatedAcmispon strigosusfrom six populations with threeBradyrhizobiumstrains that vary in symbiotic effectiveness on sympatric hosts. We measured proxies of host and symbiont fitness in single‐ and co‐inoculations under fertilization treatments of zero added nitrogen (N) and near‐growth‐saturating N. We examined two components of host control: ‘host investment’ into nodule size during single‐ and co‐inoculations, and ‘host sanctions’ against less effective strains during co‐inoculations.TheBradyrhizobiumstrains displayed conserved growth effects on hosts, and host control did not decline under experimental fertilization. Host sanctions were robust in all hosts, but host lines from different populations varied significantly in measures of host investment in both single‐ and co‐inoculation experiments.Variation in host investment could promote variation in symbiotic effectiveness and prevent the extinction of ineffectiveBradyrhizobiumfrom natural populations.