BORON DEFICIENCY SYMPTOMS AND DRY-MATTER PRODUCTION OF SESAME UNDER GREENHOUSE CONDITIONS

Boron (B) deficiency symptoms, dry matter production, and B critical values in sesame (Sesamun indicum L.) were investigated in a greenhouse experiment. Boron deficiency showed a yellowing of plant tops and of the youngest leaves. Upper leaves became dark green, coriaceous, with edges curved down. Boron-deficiency symptoms was related to 21 mu g B/g in the 30-day-old youngest fully expanded leaf. Dry matter production of leaves, stems, pods, and roots were severely decreased when B in the leaf tissue was below 21 mu g/g; however seed dry weight and seed oil content were associated to less than 39 mu g/g of B in the leaf tissue.