Kaushal Pankaj, Dwivedi Krishna K, Radhakrishna Auji, Srivastava Manoj K, Kumar Vinay, Roy Ajoy Kumar, Malaviya Devendra R
ICAR-National Institute of Biotic Stress Management, Raipur, India.
ICAR-Indian Grassland and Fodder Research Institute, Jhansi, India.
Front Plant Sci. 2019 Mar 8;10:256. doi: 10.3389/fpls.2019.00256. eCollection 2019.
Apomixis is a method of reproduction to generate clonal seeds and offers tremendous potential to fix heterozygosity and hybrid vigor. The process of apomictic seed development is complex and comprises three distinct components, viz., apomeiosis (leading to formation of unreduced egg cell), parthenogenesis (development of embryo without fertilization) and functional endosperm development. Recently, in many crops, these three components are reported to be uncoupled leading to their partitioning. This review provides insight into the recent status of our understanding surrounding partitioning apomixis components in gametophytic apomictic plants and research avenues that it offers to help understand the biology of apomixis. Possible consequences leading to diversity in seed developmental pathways, resources to understand apomixis, inheritance and identification of candidate gene(s) for partitioned components, as well as contribution towards creation of variability are all discussed. The potential of , an aposporous crop, is also discussed as a model crop to study partitioning principle and effects. Modifications in cytogenetic status, as well as endosperm imprinting effects arising due to partitioning effects, opens up new opportunities to understand and utilize apomixis components, especially towards synthesizing apomixis in crops.
无融合生殖是一种产生克隆种子的繁殖方法，具有固定杂合性和杂种优势的巨大潜力。无融合生殖种子发育过程复杂，包括三个不同的组成部分，即无孢子减数分裂（导致未减数卵细胞的形成）、孤雌生殖（未受精情况下胚胎的发育）和功能性胚乳发育。最近，在许多作物中，据报道这三个组成部分是解偶联的，从而导致它们的分离。本综述深入探讨了我们对配子体无融合生殖植物中无融合生殖组成部分分离的理解现状，以及它为帮助理解无融合生殖生物学提供的研究途径。讨论了导致种子发育途径多样性的可能后果、理解无融合生殖的资源、分离组成部分的候选基因的遗传和鉴定，以及对创造变异性的贡献。还讨论了一种无孢子作物作为研究分离原理和效应的模式作物的潜力。细胞遗传学状态的改变以及由于分离效应产生的胚乳印记效应，为理解和利用无融合生殖组成部分，特别是在作物中合成无融合生殖开辟了新的机会。
