STRAWBERRY GENOTYPES DIFFER IN THEIR RATIO OF SHOOTS TO ROOTS, BASED ON DRY WEIGHT

Previous observations of strawberry roots of plants grown in peat-based medium in a screenhouse or grown in the field in soil indicated that genotypes differ in root length and volume. This experiment was designed to evaluate a large number of genotypes to better quantify this variability and to identify those genotypes with large root systems. Plant material consisted of 100 cold-stored dormant genotypes and 71 micropropagated genotypes. Plants were grown for 8 weeks in a greenhouse, then dry weights of shoots, roots and stolons were obtained. For the cold-stored plants, root dry weight ranged from 0.74 g for ‘K99-5’ to 2.18 g for ‘Brunswick’. The shoot-to-root ratio ranged from 2.51 for ‘K03-2’ to 5.43 for ‘K99-36’, with a mean of 3.51. For the micropropagated plants, root dry weight ranged from 0.26 g for ‘BC4-41-67’ to 2.14 g for ‘WSU2464’, with a mean of 1.01 g for 71 genotypes. The shoot to root ratio ranged from 2.01 for ‘BC92-20-85’ to 6.72 for ‘BC4-9-5’, with a mean of 4.44 for 70 genotypes. Genotypes identified in this study as having large root systems or small shoot:root ratios can be used to test whether these types are more tolerant of root pathogens or abiotic stresses.