INFLUENCE OF MICRONUTRIENTS AND APPLICATION METHOD ON GROWTH, YIELD AND OIL CONTENT OF SUNFLOWER (Helianthus annuus L.)

Abstract

The field experiment was conducted at the research field of Department of Agronomy, Sher-e-Bangla Agricultural University (SAU) during the period of November, 2020 to April 2021 to evaluate the influence of soil and foliar applied micronutrients (B, Mn, Zn) on sunflower for improving physiological traits, yield and oil content. The experiment consisted of micronutrient application method and micronutrient combination. The application methods were F 1 = Soil application of micronutrient and F 2 = Foliar application of micronutrient. The 7 micronutrient treatments were T 1 = Boron, T 2 = Manganese, T 3 = Zinc T 4 = Boron+ Manganese T 5 = Boron+ Zinc T 6 = Manganese+ Zinc and T 7 = Boron+ Manganese+ Zinc. The foliar micronutrient application rate was H 3 BO 4 = 0.5 g L -1 or @ 0.5%, MnSO 4 = 1 g L or @ 1% and ZnSO 4 = 2 g L -1

or @ 2% and applied at 30 days after sowing (DAS), 50 DAS and 70 DAS. Micronutrients were applied, boron as boric acid (12 kg ha ), zinc as zinc sulphate (10 kg ha -1 ) and manganese as manganese sulphate (12 kg ha ) during final land preparation. The recommended dose of N as Urea, P as TSP and K as MoP (180:150:120 kg ha -1 ) were applied along with soil application and foliar application of micronutrient. The experiment was laid out in a RCBD factorial design with three replications. The result revealed that, F 2 (foliar application) showed significantly better crop growth like plant height at all the growth stages, number of leaf plant , leaf area index, dry matter weight, relative water content and yield contributing traits like head diameter (13.7 cm), seed head -1 (20.37), stover yield (55.12 g plant -1 ), seed yield (20.37 g plant -1 ), biological yield (87.86 g), harvest index (31.03%) and protein percentage (44.4%). The micronutrient treatment T 5 = (B+ Zn), T 6 (B+ Mn) and T 7 (B+ Mn+ Zn) showed the better performance in different yield contributing parameters. Treatment interaction of micronutrients with foliar application showed better results in yield components like head diameter, 1000 seed weight, seed head -1 , seed yield, stover yield, biological yield, harvest index, oil percentage and protein percentage.