Chemical intervention in plant sugar signalling increases yield and resilience

Abstract

The pressing global issue of food insecurity due to population growth, diminishing land and variable climate can only be addressed in agriculture by improving both maximum crop yield potential and resilience. Genetic modification is one potential solution, but has yet to achieve worldwide acceptance, particularly for crops such as wheat. Trehalose-6-phosphate (T6P), a central sugar signal in plants, regulates sucrose use and allocation, underpinning crop growth and development. Here we show that application of a chemical intervention strategy directly modulates T6P levels in planta. Plant-permeable analogues of T6P were designed and constructed based on a 'signalling-precursor' concept for permeability, ready uptake and sunlight-triggered release of T6P in planta. We show that chemical intervention in a potent sugar signal increases grain yield, whereas application to vegetative tissue improves recovery and resurrection from drought. This technology offers a means to combine increases in yield with crop stress resilience. Given the generality of the T6P pathway in plants and other small-molecule signals in biology, these studies suggest that suitable synthetic exogenous small-molecule signal precursors can be used to directly enhance plant performance and perhaps other organism function.

Transitioning to the Next Phase: The Role of Sugar Signaling throughout the Plant Life Cycle

“…Using an elegant chemical approach, it was recently shown that T6P can directly promote grain filling in wheat (Triticum aestivum). Spraying of wheat plants with compounds that release T6P upon exposure to sunlight led to increased grain yield due to the formation of larger grains with higher starch content (Griffiths et al, 2016b). Earlier work had shown that T6P naturally accumulates in wheat grains to previously unreported levels before grain filling (Martínez-Barajas et al, 2011).…”

Plant Desiccation Tolerance and its Regulation in the Foliage of Resurrection “Flowering-Plant” Species

“…T6P-inhibited SnRK1 will up-regulate carbohydrate storage, prime gene expression for growth, growth recovery and signals satiety, whereas uninhibited SnRK1 will signal starvation, catabolism and will slow growth. Indeed, the T6P:SnRK1 relationship is considered a major player in directing carbohydrates between source and sink tissues, and can be a key factor in the survival of environmental stress [116][117][118][119]. This has been addressed in Arabidopsis, where accumulated T6P under sink-limited stress conditions inhibits SnRK1 activity, and thus allows synthesis and growth to resume rapidly once the growth limiting stress conditions were alleviated [118].…”

Regulatory roles of sugars in plant growth and development

“…It was discovered in plants rather late, and it was thought that it could act in plant tissues only as an osmoprotectant under drought conditions [44]. In the last decade, trehalose-6-P was found to be essential for the normal growth and development of plants and for stable sugar metabolism [25,45,[92][93][94]. Many genes encoding Tre6P synthase and phosphatase in plants have been discovered, however, not all of their products are catalytically active [25,44].…”

“…However, lately, a model has been proposed with Tre6P as an essential factor, connecting sugars with plant growth and development [8,24,48,91,92]. The effects of Tre6P on the different stages of plant development and interaction with sugar and mediators of sugar signaling were recently discussed in detail [7,24,48,[91][92][93][94].…”