Open Access

ARTICLE

Identification and Genetic Analysis of a Novel Allelic Variation of Brittle-1 with Endosperm Mutant in Maize

Sen Wang¹, Fei Zheng¹, Meijing Zhang¹, Jun Tu², Yanping Chen^1,3, Jianhua Yuan^1,3, Qingchang Meng^1,*

1 Institute of Food Crops, Provincial Key Laboratory of Agrobiology, Jiangsu Academy of Agricultural Sciences, Nanjing, 210014, China
2 Jiangsu Zhongjiang Seed Co., Ltd., Nanjing, 211500, China
3 Jiangsu Collaborative Innovation Center for Modern Crop Production, Nanjing, 210095, China

* Corresponding Author: Qingchang Meng. Email:

Phyton-International Journal of Experimental Botany 2020, 89(4), 861-871. https://doi.org/10.32604/phyton.2020.011762

Received 28 May 2020; Accepted 18 July 2020; Issue published 09 November 2020

Abstract

Endosperm mutants are critical to the studies on both starch synthesis and metabolism and genetic improvement of starch quality in maize. In the present study, a novel maize endosperm mutant A0178 of natural variation was used as the experimental material and identified and then characterized. Through phenotypic identification, genetic analysis, main ingredients measurement and embryo rescue, development of genetic mapping population from A0178, the endosperm mutant gene was located. The results showed that the mutant exhibited extremely low germination ability as attributed to the inhibited embryo development, and amounts of sugars were accumulated in the mutant seeds and more sugars content was detected at 23 days after pollination (DAP) in A0178 than B73. Employing genetic linkage analysis, the mutant trait was mapped in the bin 5.04 on chromosome 5. Sequence analysis showed that two sites of base transversion and insertion presented in the protein coding region and non-coding region of the mutant brittle-1 (bt1), the adenylate translocator encoding gene involved in the starch synthesis. The single base insertion in the coding region cause frameshift mutation, early termination and lose of function of Brittle-1 (BT1). All results suggested that bt1 is a novel allelic gene and the causal gene of this endosperm mutant, providing insights on the mechanism of endosperm formation in maize.

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Keywords

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