Effect of fruit age and position on mother-plant on fruit growth and seed quality in okra (Abelmoschus esculentus L. Moench)

Abstract

The study was conducted at the Federal University of Technology, Minna, Nigeria. Okra (Abelmoschus esculentus L. Moench), Seeds of variety NHAe47-4 were sown at a spacing of 40 cm along ridges constructed 75 cm apart. Following emergence, thinning was done to leave one plant per stand. Flowers were date tagged at anthesis (ie immediately they opened). The fruits that developed in position 1, 3, 5 and 7 were harvested at 14, 21, 28, 35, 42, 49 and 56 days after anthesis (DAA). Seed germinability was determine before and during storage. Except for the initial increase in fruit weight between 14 and 21 DAA in position 7, no increases were generally recorded with delay in harvesting. Generally, there were no significant increases (P>5%) in fruit diameter and length in all positions between 14 and 56 DAA. However, fruits of position 7 were significantly (P<5%) shorter and slimmer than those from other positions. There were significantly fewer seeds per fruit in position 7 than in the other positions at the DAAs. The slight increase was recorded in the weight of wet seed between 14 and 21 DAA. This was followed by a decline as from 21 DAA or 28 DAA depending on fruit position. Seed moisture content declined generally with DAA and one hundred-seed weight increased between 14 and 35/42 DAA. however, position did not 100-seed weight generally. Prior to storage, germination of seeds harvested earlier than 35 DAA was poor. Germination of up to 97% and the ability of the seeds to maintain viability for long, were obtained at 42 DAA when fruits were straw-coloured, ridges completely split and the seeds were black in colour. Across DAAs, seed weight and survival ability were best in fruit positions 1, 3 and 5.