Comparative Growth Analysis of Five Basil (Ocimum basilicum L.) Cultivars in Substrate-based Drip Hydroponics

Abstract

Basil is an economically valuable herb suitable for intensive production systems where cultivation space is limited. This study compared the growth performance of five basil cultivars—Italian Large, Genovese, Red Rubin, Thai, and Selasih—under substrate-based drip hydroponics. The greenhouse experiment was conducted in Bengkulu City, Indonesia, using a randomised complete block design with five replications, giving 25 experimental units and 250 plants. Plants were grown in a 1:1 cocopeat–rice husk charcoal mixture and fertigated with AB Mix nutrient solution. Growth measurements were obtained at 14 and 70 days after transplanting. Relative growth rate, net assimilation rate, crop growth rate, leaf weight ratio, leaf area ratio, specific leaf area, specific leaf weight, leaf area duration, leaf area index, and chlorophyll content were evaluated. Data were analysed by ANOVA at the 5% significance level, followed by Duncan's Multiple Range Test when treatment effects were significant. Cultivar significantly affected crop growth rate, leaf weight ratio, leaf area duration, leaf area index, and chlorophyll content, but not the other five growth variables. Italian Large had the highest leaf weight ratio (0.88 g/g) and chlorophyll content (34.31 SPAD units), whereas Genovese recorded the highest final plant dry weight (11.45 g) and crop growth rate. These results indicate that Italian Large and Genovese are promising cultivars for substrate-based drip hydroponic basil production, with cultivar selection depending on the intended production objective.