Phenotypic variation in root development of 162 soybean accessions under hypoxia condition at the seedling stage

• Published in: Plant production science 2017-07, Vol.20 (3), p.323-335
• Main Authors: Suematsu, Keisuke, Abiko, Tomomi, Nguyen, Van Loc, Mochizuki, Toshihiro
• Format: Article
• Language: English
• Subjects: ANOVA, analysis of variance; ARD, average root diameter; CARD, change in average root diameter; core collection; Damage tolerance; DAS, days after sowing; Genetic Resources Evaluation; Hydroponics; Hypoxia; hypoxia tolerance; IRL, increment in total root length; IRSA, increment in total root surface area; IRV, increment in total root volume; LS, large plants with hypoxia-sensitive roots; LT, large plants with hypoxia-tolerant roots; PC, principal component; PCA, principal components analysis; Phenotypic variations; Plant growth; Principal components analysis; RD, Wroot dry weight; RL, total root length; Root development; root morphology; Roots; RSA, total root surface area; RV, total root volume; SDW, shoot dry weight; Seedlings; SNP, single-nucleotide polymorphism; Soils; Soybean; Soybeans; SS, small plants with hypoxia-sensitive roots; ST, small plants with hypoxia-tolerant roots; Waterlogging; waterlogging tolerance
• ISSN: 1343-943X; 1349-1008
• DOI: 10.1080/1343943X.2017.1334511

Soybean is often damaged by hypoxia caused by waterlogging at the seedling stage. Hypoxia severely inhibits root development and retards plant growth. We aimed to clarify phenotypic variation in root development under hypoxia condition at the seedling stage using diverse soybean accessions. Root development in 162 accessions was evaluated in hydroponic culture. Substantial changes under hypoxia were investigated by means of WinRHIZO analysis before and after the treatment. We found significant phenotypic variation in hypoxia tolerance in root among the 162 accessions. A principal components analysis indicated an association between hypoxia tolerance and the country of origin. We found three new accessions which have a high ability to develop roots under hypoxia (Kokubu 7, Maetsue zairai 90B, and Yahagi). Root development in selected accessions was also evaluated in soil culture. Root development levels in hydroponic and soil culture were significantly correlated. These results will provide important information on waterlogging damage in regions where waterlogging occurs. The three accessions with hypoxia-tolerant roots might be useful for genetic improvement of waterlogging tolerance of modern soybean varieties.