Boron Use in the Table Beet and the Relation of Short-term Boron Stress to Blackheart Injury

Abstract

Abstract Table beet (Beta vulgaris L.) cultivars (‘Ruby Queen’, ‘Gladiator’, and ‘Mono-King Explorer’) grown with varying B regimens had similar patterns of dry weight and B accumulation. Between 0.1 and 0.4 ppm B in solution, dry weight of leaf blades, petioles, roots, and fibrous roots did not increase. Boron content increased in leaf blades and remained constant in other plant parts. From 0.0005 to 0.011 ppm B in solution, dry weight of whole plants, shoots, and roots increased through 0.007 ppm B. Boron content increased in shoots and leaf blades through 0.011 ppm B. Distribution of dry weight and B content was reversed in these plants compared to those grown in B levels sufficient for normal development. With insufficient B levels, plants accumulated greater dry weight in shoot than root portions, and B content was greatest in root compared to shoot portions. The effect of short-term B stress on dry weight and B content varied with the growth stage at which stress was induced. Severity of B deficiency symptoms was related to length of the B stress interval. Blackheart injury of roots occurred in plants stressed during early secondary growth. Recovery from stress was associated with B stress induced prior to or after this critical developmental period.