Adhikari Prakash Babu, Liu Xiaoyan, Kasahara Ryushiro D
School of Life Sciences, Fujian Agriculture and Forestry University, Fuzhou, China.
Horticultural Plant Biology and Metabolomics Center (HBMC), Fujian Agriculture and Forestry University, Fuzhou, China.
Front Plant Sci. 2020 Jun 30;11:967. doi: 10.3389/fpls.2020.00967. eCollection 2020.
Gametophytic mutants share very small proportion of the total mutants generated by any mutagenic approach; even rarer are the fertilization-defective gametophytic mutants. They require an efficient and targeted strategy instead of 'brute force' screening approach. The classical gametophyte mutant screening method, mainly based on the segregation distortion, can distinguish gametophytic mutants from the others. However, the mutants pooled after the screening constitute both fertilization-defective and developmental-defective gametophytic mutants. Until recently, there has not been any straightforward way to screen the former from the latter. Additionally, most of the mutations affecting both gametes are lost during the screening process. The novel gametophyte screening approach tends to circumvent those shortcomings. This review discusses on the classical approach of gametophytic mutant screening and focuses on the novel approach on distinguishing fertilization-/developmental-defective gametophytic mutants (both male and female). It offers an empirical basis of screening such mutants by taking in the consideration of earlier studies on fertilization failure, initiation of seed coat formation, and fertilization recovery system in plants.
配子体突变体在任何诱变方法产生的总突变体中所占比例都非常小；受精缺陷型配子体突变体则更为罕见。它们需要一种高效且有针对性的策略，而非“蛮力”筛选方法。经典的配子体突变体筛选方法主要基于分离畸变，能够将配子体突变体与其他突变体区分开来。然而，筛选后汇集的突变体既包括受精缺陷型配子体突变体，也包括发育缺陷型配子体突变体。直到最近，还没有任何直接的方法从后者中筛选出前者。此外，大多数影响雌雄配子的突变在筛选过程中都会丢失。新颖的配子体筛选方法倾向于规避这些缺点。本文综述了配子体突变体筛选的经典方法，并着重介绍了区分受精缺陷型/发育缺陷型配子体突变体（包括雄配子体和雌配子体）的新颖方法。它通过考虑植物受精失败、种皮形成起始以及受精恢复系统的早期研究，为筛选此类突变体提供了经验依据。
