Study on Thermotherapy Treatment Effects on Seed Germination and Vigor of Tomato Cultivars

Abstract

Hot water treatment presents great potential on the alternative control of seedpathogens.This research aimed to study the relation of hot water treatment to germination and vigorof tomato seeds of 3 varieties, to identify maximum combinations of temperature andexposure time of seeds with no detrimental effect on germination and vigor. Theexperiment was conducted as factorial based on complete randomized design in 3replications. The treatments were cultivar at 3 levels(Super Star, Super Urbana andQueen), temperature in 5 levels(48, 52, 56, 60°C and control) and time of treatment in 4levels(10,20,30 and 40 minutes). The measured traits were germination percent,germination rate, and some seed vigor aspects including seedling radicle length andshoot length and seedling dry weight. The analysis of variance showed seeds treatmentin temperatures of 56°C and 60°C for 30 and 40 min had detrimental effect ongermination and vigor. There was a significant difference among cultivars in germinationpercent and germination rate, especially at higher temperatures. Queen cultivar showedbetter germination ability and Super Star was the most sensitiveto high temperatures (56and 60°C) and had the lowest germination ability and vigor.