Abstract

Plant growth hormones play a vital role in guava production and are used in the induction of flowering, help in fruit set, fruit thinning, fruit elongation, premature fruit drop prevention, fruiting buds development and inhibiting ripening process. These can also influence the size, appearance and quality parameters of fruits. By using plant hormones, an experiment was carried out in the Experimental Farm and Laboratory, Department of Horticulture, College of Agriculture, Assam Agricultural University, Jorhat during 2016–18 to regulate the flowering of guava in the rainy season and to increase more production and productivity of guava fruit in the winter season. A total of six treatments with four replications and two seasons (rainy and winter) were laid out in a randomized block design. The effect in foliar application of different concentrations of plant growth hormones of T1-Naphthalene acetic acid (NAA at 100 ppm), T2-Naphthalene acetamide (NAD at 40 ppm), T3-Naphthalene acetamide (NAD at 60 ppm), T4-Urea (2%), T5-Urea (5%) and T6-Urea (10%) at flowering stage in the month of April, 2017 helped in deblossoming of flowers, enhanced fruit size, weight, number of flowers and fruits, reduced fruit drop (76.43% in rainy season to 38.26%), decreased the days required for maturity (118 days) and increased the yield (20.73 kg/plant) in the winter season. The effect of NAD @ 60 ppm gave the best result in fulfilling all the physical parameters of the guava fruit in the winter season.