Effects of ethephon on tabasco pepper fruit ripening and abscission at the fruit–receptacle junction

Abstract

Effects of ethephon on tabasco ( Capsicum frutescens L.) pepper fruit ripening and abscission at the fruit–receptacle abscission zone (FR–AZ) were studied in two lines, ‘McIlhenny Select’ and ‘Hard Pick’. Fruit color development and changes in fruit detachment force (FDF) were correlated in both tabasco lines; FDF decreased significantly at color stages 3 and 4 in ‘McIlhenny Select’ fruit and at stages 5 and 6 in ‘Hard Pick’ fruit based on a scale of 0 for green-mature and 7 for red-mature. The two tabasco lines had different FDF at the FR-AZ; FDF was significantly lower in ‘McIlhenny Select’ than in ‘Hard Pick’ after color stage 3 and was 5-fold lower in ‘McIlhenny Select’ than in ‘Hard Pick’ at the red-mature stage. There were also differences between the two lines in the time for reduction of FDF, which occurred 40 and 42 days after anthesis (DAA) in water-treated ‘McIlhenny Select’ and ‘Hard Pick’ fruit, respectively. Ethephon treatment (1000 μl l −1) decreased FDF at 36 DAA in ‘McIlhenny Select’ and 38 DAA in ‘Hard Pick’. Ethephon applied at 29 and 32 DAA decreased the fruit development period by 3–7 days in both lines. Ethephon did not affect ‘McIlhenny Select’ fruit at 35 and 38 DAA, while treatment of ‘Hard Pick’ fruit of the same developmental stage shortened the developmental period.