Breeding for cuticle-associated traits in crop species: traits, targets, and strategies

Abstract

Improving crop productivity and quality while promoting sustainable agriculture have become major goals in plant breeding. The cuticle is a natural film covering the aerial organs of plants and consists of lipid polyesters covered and embedded with wax. The cuticle protects plants against water loss and pathogens and affects traits with strong impacts on crop quality such as, for horticultural crops, fruit brightness, cracking, russeting, netting, and shelf life. Here we provide an overview of the most important cuticle-associated traits that can be targeted for crop improvement. To date, most studies on cuticle-associated traits aimed at crop breeding have been done on fleshy fruits. Less information is available for staple crops such as rice, wheat or maize. Here we present new insights into cuticle formation and properties resulting from the study of genetic resources available for the various crop species. Our review also covers the current strategies and tools aimed at exploiting available natural and artificially induced genetic diversity and the technologies used to transfer the beneficial alleles affecting cuticle-associated traits to commercial varieties.

Assembly of the Cutin Polyester: From Cells to Extracellular Cell Walls

“…These functions include resistance to biotic and abiotic stress, plant growth and development, water repellence, exchange of water and gas between plants and their environments, protection against UV radiation and retention of both polar and hydrophobic molecules [ 5 ]. All of these properties define not only the agronomical quality of crops, but also their food quality and end-uses [ 6 ]. Furthermore, it is important to take into account that different by-products concentrate cuticular layers such as cereal brans and fruit pomaces provided by the corresponding food industries.…”

“…In the last past ten years, these different settings fit with what it is now called the bioeconomy and motivated numerous researches to delineate the structure, the biosynthesis and extracellular assembly of cuticular components in relation with their (bio)functional properties. These studies have mainly profited of the use of collection of T-DNA mutants (e.g., Arabidopsis , rice) and other genetic tools (RNA interference, Transfer DNA, Targeting Induced Local Lesions in Genomes) coupled to the development of high resolution and complementary biophysical techniques [ 6 ]. This review will report the most recent data on the structure and assembly of the cuticular polymers with a special emphasis on the cutin polyester.…”

Analysis of biosynthesis and composition of cuticular wax in wild type bilberry (Vaccinium myrtillusL.) and its glossy mutant

“…Cuticle is a lipophilic layer on aerial parts of plant surface, composed of cuticular wax and cutin, a polyester polymer matrix. Cuticle plays an important role in preventing water loss, protection against UV radiation and pathogen attack in plants, including fruits at different developmental stages and during storage period (Lara et al ., 2014; Petit et al , 2017). Cuticular wax is a complex mixture of very long chain fatty acids (VLCFAs) and their derivatives, such as aldehydes, alkanes, ketones, primary and secondary alcohols, esters as well as secondary metabolites, including triterpenoids, sterols, and phenolic compounds (Kunst and Samuels, 2009; Lara et al ., 2015).…”

Genome-wide association study for maize leaf cuticular conductance identifies candidate genes involved in the regulation of cuticle development

“…There is a longstanding interest in breeding for cuticle-related traits such as drought tolerance, but the complexity of the relationship between cuticle composition and resistance to dehydration, and the lack of methods amenable to high-throughput phenotyping for cuticle-associated traits, has hampered progress in this area (Petit et al . 2017).…”