EFFECT OF HARVESTING STAGES AND HYDRO DORMANCY BREAKING TREATMENT ON SEED PHYSIOLOGICAL ATTRIBUTES OF Solanum macrocarpon (EGGPLANT)

Abstract

ABSTRACT Seed germination is a critical phase in plant life cycle which is affected by dormancy and environmental factors. This study was carried out at Federal University of Agriculture, Abeokuta to investigate the effects of green yellowish and brown harvesting stages on the field and hydro-priming treatments on seed physiological attributes in the laboratory of six African eggplant genotypes (Solanum macrocarpon L.) between April and August 2021. A factorial experiment of 6×2×3×7; genotypes, harvesting stage, hydro-priming methods and levels of hydro-priming methods respectively. The field experiment was set up in a randomized complete block design with three replications per plot size of 20 m by 16 m with a bed size of 2 m by 3 m for each genotypes at a spacing of 50 cm by 50 cm for inter-row and intra-row respectively, for double row planting. Completely randomized design was used in the laboratory experiment in three replicates. Seedlots of the six genotypes were subjected to hydro-priming treatments; water at room temperature, hot water and control (without water). This was achieved by putting 1000 seeds of each treatment combinations inside a cloth bag and then soaked in water at room temperature for five soaking durations (2, 4, 6, 8 and 10 hours). The treated seeds were left to dry under room temperature for seven days. For hot water treatment, 1000 clean seeds were put in a cloth bag and soaked in hot water at 100 0C for ten seconds and later left to cool in water at room temperature and then left to dry for 7 days under room temperature. fruit weight, fruit length and diameter, number of seed per pod data were collected on the field while in the laboratory, data collected were; seed germination, seedling height, seedling vigour index, days to 50% germination. Data collected were subjected to combined analysis of variance and significant treatment means separated at 5% probability level using Tukey’s HSD test. Correlation coefficient analysis among seed quality traits across hydro-priming techniques was carried out. Significant differences (p≤ 0.05) were observed among the six genotypes of S. macrocarpon, hydro-priming treatments and between the two harvest stages. Seed germination percentage was greater when fruits were harvested at the brown dry stage than at less mature stage (green yellowish stage). Seed dormancy of Solanum macrocarpon can be broken by exposing the harvested matured seeds to water at room temperature for 10 hours. Seeds of fruits harvested at green yellowish fruit stage were of very poor quality. Fruits of genotypes NGBO 0772, NGBO 0266 and NGBO 7715 harvested at brown fruits colour stage exposed to water at room temperature for 10 hours retained maximum seed germination with good attributing traits. The study indicated that seed quality of S. macrocarpon genotypes increases with harvest maturity stage and increases in germination and vigour parameters. Fruits of genotypes (NGBO 0772, NGBO 0266 and NGBO 7715) harvested at brown fruit colour stage exposed to water at room temperature for 10 hours are recommended to farmers and seed companies.