Plastid Inheritance, Physiology, and Fitness in Medicago sativia

最近的研究表明，双亲本遗传质体（BIP）在植物界可能比以前认为的更普遍。在被研究的被子植物类群中，大约20%的质体是双亲遗传的。人们提出了各种各样的假设来解释植物质体遗传模式的基础，然而，人们对这些遗传模式的进化意义知之甚少。我们对表现出规律BIP的紫花苜蓿（Medicago sativa）的研究表明，该物种的孢子体质体组成（母系、父系或双亲本）可能存在适合度效应。在有BIP的物种中，质体也可以为发育中的小配子体、精子或受精卵提供能量来源。这里描述的研究将考虑这两种可能的解释来解释BIP的存在。利用具有明确体质的全同胞家族，我们拟测定1)孢子体质体组成对紫花苜蓿基本生理过程和适合度组分的影响。测量将集中在受质体-核相互作用影响的生理性状和可能反映初级代谢差异的整个植物特性上。

Recent research demonstrates that biparental inheritance of plastids (BIP) may be more common in the plant kingdom than previously thought. Plastids are inherited biparentally in approximately 20% of angiosperm taxa studied. Various hypotheses have been presented to explain the basis for patterns of plastid inheritance in plants, however, very little is understood regarding the evolutionary significance of these inheritance patterns. Our research with alfalfa (Medicago sativa), which exhibits regular BIP, suggests that there may be fitness effects associated with sporophyte plastid composition (maternal, paternal, or biparental) in this species. Plastids may also provide an energy source for the developing microgametophyte, sperm or the fertilized egg in species with BIP. The research described here would consider these two possible explanations for the existence of the BIP. Using sets of full-sib families with defined constitutions, we propose to measure the effects of 1) plastid composition in sporophytes on basic physiological processes and components of fitness in alfalfa. Measurement would concentrate on physiological traits influenced by plastid-nucleus interaction and whole-plant characteristics that may reflect differences in primary metabolism.