Agrobacterium tumefaciens Susceptibility and Plant Regeneration of 10 Soybean Genotypes in Maturity Groups 00 to II

Abstract

Agrobacterium‐mediated transformation of soybean [Glycine max (L.) Merr.] plants is affected by the susceptibility of genotypes to specific Agrobacterium strains and by the ability to regenerate plants from transformed cells of those genotypes. The objectives of this study were to: (i) determine susceptibility of cotyledons from 10 Maturity Group 00 to II soybean genotypes to strains C58, A208, and A281 of A. tumefaciens and, (ii) determine the frequency of plant regeneration from tissue cultures of the same soybean genotypes. Cotyledons from 1‐d‐old axenic seedlings of the 10 genotypes and ‘Peking,’ a highly susceptible Maturity Group IV cuitivar, were excised, wounded, and inoculated with the A. tumefaciens strains. The relative frequency of tumor formation, an indicator of susceptibility, was greatest for strains C58 and A208 on all soybean genotypes tested. The soybean genotypes Peking and PI 180529 were most susceptible. The same genotypes were evaluated from shoot organogenic tissue culture initiation from the cotyledonary node and plant regeneration via adventitiou shoot formation. The genotypes producing the highest frequency of mature plants during 30 weeks after culture initiation were Experimental Line HHP, ‘Evans’, PI 445799, ‘Hodgson 78’, ‘Corsoy 79’, and PI 180529. These may be useful genotypes for whole plant transformation studies.