Biology subjects

Dubcovsky, J.

Publications and source records attributed to Dubcovsky, J..

2 recordsLinked to original sources

bioRxiv2019

Wheat VRN1 and FUL2 play critical and redundant roles in spikelet meristem identity and spike determinacy

The spikelet is the basic unit of the grass inflorescence. In this study, we show that wheat MADS-box genes VRN1, FUL2 and FUL3 play critical and redundant roles in spikelet and spike development, and also affect flowering time and plant height. In the vrn1ful2ful3-null triple mutant, the inflorescence meristem formed a normal double-ridge structure, but then the lateral meristems generated vegetative tillers subtended by leaves instead of spikelets. These results suggest an essential role of these three genes in the determination of spikelet meristem identity and the suppression of the lower ridge. Inflorescence meristems of vrn1ful2ful3-null and vrn1ful2-null remained indeterminate and single vrn1-null and ful2-null mutants showed delayed formation of the terminal spikelet and increased number of spikelets per spike. Moreover, the ful2-null mutant showed more florets per spikelet, which together with a higher number of spikelets, resulted in a significant increase in the number of grains per spike in the field. Our results suggest that a better understanding of the mechanisms underlying wheat spikelet and spike development can inform future strategies to improve grain yield in wheat.\n\nSUMMARY STATEMENTThe wheat MADS-box proteins VRN1, FUL2 and FUL3 play critical and overlapping roles in the development of spikelets, which are the basic unit of all grass inflorescences.

developmental biology↗

bioRxiv2018

A wheat/rye polymorphism affects seminal root length and is associated with drought and waterlogging tolerance

The introgression of a small segment of wheat chromosome 1BS in the distal region of the rye 1RS arm translocation in wheat (henceforth 1RSrw) was previously associated with reduced grain yield, carbon isotope discrimination and stomatal conductance, suggesting reduced access to soil moisture. In this study, we show that the 1RS/1RSRW polymorphism causes differences in root length in field and hydroponic experiments. In the latter, differences in seminal root length were associated with a developmentally regulated arrest of the root apical meristem (RAM). Approximately 10 days after germination, the seminal roots of the 1RSRW plants showed a gradual reduction in elongation rate and stopped growing a week later. Seventeen days after germination, the roots of the 1RSRW plants showed altered gradients of reactive oxygen species and emergence of lateral roots close to the RAM, suggesting a loss of apical dominance. The 1RS/1RSRW isogenic lines also differed in plant biomass and grain yield under normal, terminal drought, and waterlogging field conditions. The differences were larger in fields with reduced or excessive irrigation. These results suggest that this polymorphism may be useful to modulate root architecture and mitigate the negative impacts of excess or reduced water in wheat production.\n\nHIGHLIGHTA wheat/rye polymorphism in chromosome one affects seminal root length and apical dominance and is associated with differences in drought and waterlogging tolerance in the field.

plant biology↗