Effect of Gibberellic Acid on Germination and Growth Responses of Pummelo Seedlings under Eastern Himalayan Foothills

Abstract

The research was conducted at Uttar Banga Krishi Viswavidyalaya, Cooch Behar
district of West Bengal, under eastern Himalayan foothills during the year 2019–2020. This
trial was aimed to evaluate the effect of seed treatment of pummelo with varying
concentrations of gibberellic acid (GA3) on germination and successive growth behaviour of
seedlings. Seven treatments were employed viz., Control, 50 ppm GA3, 100 ppmGA3, 150
ppm GA3, 200 ppm GA3, 250 ppm GA3 and 300 ppm GA3 and each treatment was replicated
three times. All treatments significantly performed better as compared to control. According
to the results obtained, treatment with 300 ppm GA3 was found to be superior among all the
treatments with highest germination percentage (98.33 %), germination value (5.30), shortest
minimum days to germination (18.83), mean germination time (27.95), maximum number of
leaves (13.67), number of roots (29.00), shoot length (26.33 cm), root length (21.40 cm),
seedling length (47.73 cm), seedling vigour index (4693.90), fresh root weight (1.80 g), fresh
shoot weight (1.33 g), fresh leaf weight (3.67 g), dry root weight (0.77 g), dry shoot weight
(0.52 g), dry leaf weight (0.96 g), root:shoot ratio (0.52) and total biomass (2.25 g plant-1).
Therefore, pre-sowing treatment of pummelo seeds with 300 ppm GA3 may be recommended
to the growers to enhance germination and growth of seedlings leading to the production of
vigorous plants which can be utilized in crop improvement programme as well as rootstock
studies.