Preliminary Studies on Fruit Lignification Time Interval and Phenological Traits of Selected Okra (Abelmoschus esculentus L Moench) Genotypes Grown in Southern Nigeria

Abstract

Aims: To determine the time interval between fruit formation and lignification (hardening of fruits) and phonological traits in three short, early maturing and three tall, late maturing genotypes of Okra (Abelmoschus esculentus L Moench) grown in southern Nigeria. Study Design: Two separate experiments for the dwarf early maturing and tall late maturing genotypes were laid out in a randomized complete block design with five replications. Place and Duration of Study: The study was conducted in Calabar rainforest agro-ecology in 2014 and 2015 vegetables growing seasons. Methodology: Fruit lignification time interval was determine using the direct time measurement using stop watch and observation of the time interval between fruit formation to time of hardening (Lignification). Data for phenological traits were generated from direct measurements using appropriate tools and observations of okra plants in the field. Results: Results showed that the tall, late maturing okra genotypes required longer time interval to become lignified compared to the dwarf, early maturing genotypes throughout the period of study.  Results of time interval measurement showed that significant (p<0.05) differences were detected among genotypes. A time interval of 142±4.50 hours was required for fruit lignification in Perkins long pod, while ‘Etighi idok’ and ‘Okpo-mbontam’ genotypes required 124±3.40 and 96±5.15 hours respectively to become lignified. The dwarf, early maturing genotypes, NHAe-47-4 fruits become lignified after 124±3.45 hours, ‘Asaka awum’ fruits required 121±4.20 hours while Agwu early took 78±3.25 hours to become unusable in fresh conditions. Results of phenological traits of Okra genotypes also revealed that the tall, late maturing genotypes had more branches per plant, more fruits per plant, longer fruiting period and longer days to flower and fruiting initiation compared to the dwarf, early maturing genotypes. Conclusion: Knowledge of fruit lignification time interval in Okra will no doubt reduce the laborious task of daily handpicking of immature fruits, reduce the rate of spoilage of the vegetable, enable for the consumption of fresh rather than dried okra and for plan and controlled harvesting of fruits for the market, income and food security.