Journal Article

Evaluation of root traits in F2-progeny of interspecific hybrid between Lotus corniculatus “Super-Root” and tetraploid Lotus japonicus

Hidenori Tanaka, Ryo Akashi, Masatsugu Hashiguchi, Genki Ishigaki, Rinda Puspasari, Ryoma Ushio

2020

Overview

Aim “Super-Root” (SR) is a fast-growing root culture established in the legume forage species Lotus corniculatus that displays vigorous growth and high embryogenic capacity, uniquely allowing for continuous root cloning, direct somatic embryogenesis, and mass regeneration of plants under hormone-free culture conditions . This study’s primary aim was to verify the possibility of introducing the SR trait to another legume species as a means of enhancing root traits. Our previous research produced a F 1 -generation hybrid between the colchicine-doubled form of the diploid Lotus japonicus ‘Miyakojima’ MG-20 and SR-derived Lotus corniculatus . The current study’s focus was to evaluate the root phenotype of the F 2 -generation to confirm the introduction of SR characteristics to Lotus japonicus . Methods We assessed 242 rooted F 2 -hybrid progeny using cluster analysis, concentrating on four morphological root traits: root fresh weight, total root length, maximum root length, and root diameter. Principal Component Analysis (PCA) was used to determine the correlations among eight traits of the F 2 -progeny of the WinRhizo root morphological measurement data and to identify what traits contributed most to their root variation. Results The 242-hybrid progeny and both parents were grouped into eight different clusters using a similarity phenogram. One cluster consisted of lines 36, 82, 86 and 184 that considerably exceeded the RFW, TRL, and MRL values of the L. japonicus and SR parents. Conclusion The results confirmed the introduction of SR traits to the F 2 -hybrid progeny and identified potential candidates for breeding and gene isolation that will be conducted to expand the scope of this research.

• Publisher: Springer Science and Business Media LLC,Springer International Publishing,Springer Nature B.V
• Subject: Biomedical and Life Sciences / Cloning / Cluster analysis / Colchicine / Diameters / Diploids / diploidy / Ecology / Embryonic growth stage / Evaluation / forage / genes / hybrids / Interspecific / Legumes / Leguminous plants / Life Sciences / Lotus corniculatus / Lotus corniculatus var. japonicus / Lotus japonicus / Morphology / Offspring / phenotype / Phenotypes / Plant growth / Plant Physiology / Plant Sciences / principal component analysis / Principal components analysis / Progeny / Regeneration / Regular Article / soil / Soil Science & Conservation / Somatic embryogenesis / tetraploidy