Key message

The field survey in this article showed in ‘KU50’, a popular variety and late-branching type of cassava in Southeast Asia, that flowering rarely occurs in normal-field conditions in Southeast Asia but is strongly induced in the dry season in the mountainous region. Flowering time is correlated with the expression patterns of MeFT1 and homologs of Arabidopsis GI, PHYA, and NF-Ys.

Abstract

Cassava (Manihot esculenta Crantz) is a tropical crop that is propagated vegetatively rather than sexually by seed. Flowering rarely occurs in the erect-type variety grown in Southeast Asia, but it is known that cassava produces flowers every year in mountainous regions. Data pertaining to the effect of environmental factors on flowering time and gene expression in cassava, however, is limited. The aim of the present study was to determine the kinds of environmental conditions that regulate flowering time in cassava and the underlying molecular mechanisms. The flowering status of KU50, a popular variety in Southeast Asia and late-branching type of cassava, was monitored in six fields in Vietnam and Cambodia. At non-flowering and flowering field locations in North Vietnam, the two FLOWERING LOCUS T (FT)-like genes, MeFT1 and MeFT2, were characterized by qPCR, and the pattern of expression of flowering-related genes and genes responsive to environmental signals were analyzed by using RNA sequencing data from time-series samples. Results indicate that cassava flowering was induced in the dry season in the mountain region, and that flowering time was correlated with the expression of MeFT1, and homologs of Arabidopsis GI, PHYA, and NF-Ys. Based upon these data, we hypothesize that floral induction in cassava is triggered by some conditions present in the mountain regions during the dry season.

中文翻译：

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田间转录组分析揭示了东南亚山区环境中木薯开花的分子机制。

关键信息

本文的田间调查表明，在东南亚流行的晚分枝型木薯品种‘KU50’中，开花在东南亚正常田间条件下很少发生，而在山区旱季则强烈诱导开花。 . 开花时间与MeFT1和拟南芥 GI、PHYA和NF-Ys同源物的表达模式相关。

抽象的

木薯（Manihot esculenta Crantz ）是一种热带作物，通过无性繁殖而不是通过种子有性繁殖。在东南亚种植的直立型品种很少开花，但众所周知，木薯在山区每年都会开花。然而，有关环境因素对木薯开花时间和基因表达影响的数据是有限的。本研究的目的是确定调节木薯开花时间的环境条件及其潜在的分子机制。在越南和柬埔寨的六个大田中监测了东南亚流行品种、晚分枝型木薯 KU50 的开花状况。在越南北部的非开花和开花田地，两个FLOWERING LOCUS T( FT ) 样基因MeFT1 和 MeFT2通过 qPCR 进行了表征，并使用来自时间序列样本的 RNA 测序数据分析了开花相关基因和对环境信号有反应的基因的表达模式。结果表明，在山区旱季诱导木薯开花，开花时间与MeFT1、拟南芥GI、PHYA和NF-Ys同源基因的表达相关。基于这些数据，我们假设木薯的开花诱导是由旱季山区存在的一些条件引发的。