Effect of boron foliar application on growth, yield and seed quality of sunflower (Helianthus annuus L.) grown in Hochiminh, Vietnam

Abstract

Boron (B) is one of the essential micronutrients for sunflower that is required in rather large quantity to achieve a good yield. A field trial comparing boron foliar application rates (0, 200, 400, 600, 800 g B/ha) to sunflower's response was carried out on the loamy sand soil in Thu Duc district, Hochiminh City, Vietnam. Treatments were arranged in a randomized complete block design with 3 replications. The results showed that foliar boron application improved plant growth, development, and quality of sunflower seeds. The highest plant height (97.04 cm), number of leaves (31.3), shoot diameter (2.68 cm), number of seeds/head (743.4), seed yield (1.26 ton/ha), and total protein content (281.0 mg/g) were obtained at vate of 600 g B/ha. The seed yield strongly correlated with the number of seeds/head (r = 0.99**), less closely correlated with the weight of 1000 seeds (r = 0.35), but not associated with total protein and total amino acids contents in seeds. The maximum profit to sale was achieved at the treatment of 600 g B/ha.