Hort. Sci. (Prague), X:X | DOI: 10.17221/47/2025-HORTSCI

Investigating the role of 6-BAP and 2,4-DPA in enhancing biochemical nutrients and reducing fruit drop and cracking of litchi cv. BombaiOriginal Paper

Bikash Chandra Sarker¹, Shams Shaila Islam², Kanij Farhana¹, M.A. Hakim¹, Thanet Khomphet ORCID...³

¹ Department of Agricultural Chemistry, Hajee Mohammad Danesh Science and Technology University, Dinajpur, Bangladesh

² Department of Agronomy, Hajee Mohammad Danesh Science and Technology University, Dinajpur, Bangladesh

³ School of Agricultural Technology and Food Industry, Walailak University, Nakhon Si Thammarat, Thailand

Litchi fruit dropping is a major issue that leads to low yields while degrading biochemical nutrient qualities by fruit cracking and reduced income for litchi growers in Bangladesh. To address this, an experiment was conducted to determine the effects of biochemical nutrients and the ability to reduce fruit cracking and dropping in the litchi cv. ‘Bombai’ under various concentrations of 6-benzylaminopurine (6-BAP) and 2,4-dichlorophenoxyacetic acid (2,4-DPA). The study followed a two-factor factorial experiment in a randomised complete block design, using four levels for each growth regulator: control, 20, 30, and 40 ppm 2,4-DPA, and similarly for 6-BAP. Various parameters were measured, including the number of flowers, fruit retention, fruit cracking, moisture content, ash content, acidity, fruit growth, and fruit quality, as well as yield per tree. The results demonstrated that both plant growth regulators, 2,4-DPA and 6-BAP, significantly reduced fruit dropping and cracking while improving the overall quality and nutrient content of the fruits. The retention of fruits was higher with 6-BAP compared to 2,4-DPA. The highest fruit weight, length, diameter, pulp-to-seed ratio, and pulp-to-peel ratio were achieved with the 20 ppm treatments of both 2,4-DPA and 6-BAP. Additionally, biochemical fruit quality indicators, including vitamin C, vitamin A, total phenol content, and key mineral nutrients, were significantly enhanced by both growth regulators. Based on the findings, it is recommended that either 20 ppm of 2,4-DPA or 20 ppm of 6-BAP be applied three times at the pea-size, marble-size, and pre-harvest stages after fruit set to enhance fruit quality by reducing fruit crack and reducing fruit drop resulted in higher yield in litchi.

Keywords: food nutrients; fruit cracking; fruit retention; litchi; yield enhancement

Received: April 1, 2025; Revised: September 19, 2025; Accepted: October 15, 2025; Prepublished online: June 1, 2026