Boron deficiency in cole crops under field and greenhouse conditions

Abstract

Abstract Field and greenhouse experiments were conducted on a Charlottetown fine sandy loam soil containing 0.28 ppm hot‐water‐soluble (hws) B. Broccoli, Brussels sprouts and cauliflower grown without added B showed B deficiency symptoms in the form of yellowing of leaves and in the case of cauliflower purplish colored inward curled leaf edges were also noted under greenhouse conditions. Under field conditions, however, only broccoli showed symptoms of B deficiency in the form of browning of older leaf edges. Application of B increased plant growth about 3‐fold under greenhouse conditions, while in the field experiment B increased the yield of broccoli and cauliflower by about 20%. The decreased yields of broccoli, Brussels sprouts and cauliflower with B deficiency leaf disorders under greenhouse conditions were associated with plant tissue B concentrations of 2.4, 6.6 and 4.2 ppm, respectively, in the three crops. Under field conditions, B deficiency symptoms in broccoli, and reduced yields in broccoli and cauliflower were associated with 7.8 to 9.1 ppm B in the leaf tissue. Liming the soil from pH 6.0 to 6.6 increased the yield of cauliflower but had no effect on broccoli and Brussels sprouts yields or on the concentration of B in broccoli and cauliflower tissue.