Assessment of Drought Tolerance of Miscanthus Genotypes through Dry-Down Treatment and Fixed-Soil-Moisture-Content Techniques

• Published in: Agriculture (Basel) Vol. 12; no. 1; p. 6
• Main Authors: Weng, Tzu-Ya, Nakashima, Taiken, Villanueva-Morales, Antonio, Stewart, J. Ryan, Sacks, Erik J., Yamada, Toshihiko
• Format: Journal Article
• Language: English
• Published: Basel MDPI AG 01.01.2022
• Subjects: automated irrigation control; bioenergy crops; Biomass; Clusters; Corn; Diploids; Drought; Drought resistance; drought tolerance; Efficiency; Energy crops; Experiments; Genotypes; Germplasm; Irrigation systems; Miscanthus; Miscanthus sinensis; Miscanthus spp; Moisture content; Photosynthesis; photosynthetic parameters; Physiological responses; Physiology; Plant tolerance; Ploidy; Principal components analysis; Rain; Renewable energy; Soil moisture; Stress; Water content; China; Japan; Russia
• DOI: 10.3390/agriculture12010006
• ISSN: 2077-0472

Miscanthus, a high-yielding, warm-season C4 grass, shows promise as a potential bioenergy crop in temperate regions. However, drought may restrain productivity of most genotypes. In this study, total 29 Miscanthus genotypes of East-Asian origin were screened for drought tolerance with two methods, a dry-down treatment in two locations and a system where soil moisture content (SMC) was maintained at fixed levels using an automatic irrigation system in one location. One genotype, Miscanthus sinensis PMS-285, showed relatively high drought-tolerance capacity under moderate drought stress. Miscanthus sinensis PMS-285, aligned with the M. sinensis ‘Yangtze-Qinling’ genetic cluster, had relatively high principal component analysis ranking values in both two locations experiments, Hokkaido University and Brigham Young University. Genotypes derived from the ‘Yangtze-Qinling’ genetic cluster showed relatively greater photosynthetic performance than other genetic clusters, suggesting germplasm from this group could be a potential source of drought-tolerant plant material. Diploid genotypes showed stronger drought tolerance than tetraploid genotypes, suggesting ploidy could be an influential factor for this trait. Of the two methods, the dry-down treatment appears more suitable for selecting drought-tolerant genotypes given that it reflects water-stress conditions in the field. However, the fixed-SMC experiment may be good for understanding the physiological responses of plants to relatively constant water-stress levels.