Abstract

A study was undertaken to determine the thermo-tolerance of 4 month old dwarf Cavendish banana plants of cultivar "Malindi" planted using suckers. The electrolyte leakage procedure was used to generate sigmoidal curves from which the thermo-tolerance was determined at 50% electrolyte leakage. A completely randomized design (CRD) with three replicates was used. Leaflets (1.2 cm width × 5 cm length) from third fully opened leaves of plants fertilized by composted dairy cow manure and mineral fertilizers were exposed to heat regimes ranging from 30 to 80°C (at 5°C increments) for 30 min and 23°C (room temperature) as control. The results revealed that there was a positive strong correlation between heat regimes and electrolyte leakage percentage (r² = 0.73, p ≤ 0.01). Lethal temperature for Malindi banana plants was 58°C. The present investigation provided an accurate determination for heat tolerance of dwarf Cavendish banana cultivar "Malindi" and thus helps banana farmers to well manage their plants during such harsh weather conditions.

Key words: Dwarf Cavendish banana, electrolyte leakage, heat stress, thermo-tolerance.