Effect of Salt Stress levels on growth and Yield of two Cultivars of Okra (Abelmoschus esculentus (L.) Moench) (Clemson spineless and Baby bubba) in Northern Guinea Savanna Agroecological Zone of Nigeria

Abstract

Salinity stress is a major abiotic factor that significantly impacts the growth, development, and productivity of crops. This study aimed to assess the effect of salt stress on two okra cultivars, Abelmoschus esculentus (L.) Moench: Clemson Spineless and Baby Bubba. The research was carried out at the Biological Garden, Department of Biological Sciences,Federal University of Kashere, Gombe State, Nigeria. The experimental design used was Randomized Complete Block Design (RCBD), with statistical analysis performed using ANOVA, followed by Duncan’s Multiple Range Test (DMRT) at P<0.05 to separate the means. Five different salt treatments were applied to the plants using NaCl concentrations of 0 mg, 640 mg, 1280 mg, 1920 mg, and 2560 mg per liter of water. Each treatment was replicated three times for each variety. Growth parameters such as plant height, stem girth, number of leaves and leaf area were measured throughout the experiment. At high stress levels (1280mg and beyond), differences become more pronounced, especially in plant height, stem girth, and leaf number. This highlights the negative effects of salt stress on growth. The results showed that  lemson Spineless produced the highest number of fruits, while Baby Bubba had the greatest fruit weight across all salinity treatments. However, Baby Bubba demonstrated better tolerance to salinity stress, as all plants exposed to the highest salinity level of 2560 mg/L died after 6 weeks, while Clemson Spineless succumbed to the same concentration after only 4 weeks. Based on these findings, Baby Bubba is recommended for cultivation in areas with high salinity stress in Gombe State and other regions in Nigeria with similar environmental conditions. In the absence of Baby Bubba, Clemson Spineless can be used as a viable alternative.