Evaluation of the agronomic performance of nerium genotypes (Nerium oleander L.) under the Eastern dry zone of Karnataka

Abstract

Nerium oleander is a popular shrub because of its drought-tolerant capacity and least susceptibility to pests and diseases. Despite its widespread cultivation in tropical and subtropical regions, there has been a lack of information on the performance of different genotypes regarding growth and yield parameters. The present study aimed to assess the performance of ten different Nerium genotypes for growth and yield traits. Genotypes were procured from various nurseries in the suburbs of Bengaluru. The collection of genotypes was based on flower morphology, flower colour, the stature of plants, and leaf variegation. A randomised complete block design with three replications was used and 1.2 m × 1.2 m spacing was followed throughout January 2018 to April 2019. The observations were made every 60 days up to 300 DAP (Days After Planting), and there were notable variations in the growth and yield metrics of the genotypes. Five tagged plants in each replication were used to record all observations. Genotype BNC-1 (Bengaluru Nerium Collection- 1) recorded the highest value for plant height (107.33 cm), plant spread (1770.66 cm²), chlorophyll (1.16 mg/g) as well as yield of flower per plant and per hectare (1.85 kg and 12.73 t respectively) while genotype BNC-6 (Bengaluru Nerium Collection- 6) recorded the highest number of branches (45.00). The lowest flower yield per plant and hectare was observed in BNC-6 (0.32 kg and 2.26 t, respectively). In conclusion, genotype BNC-1 exhibits characteristics warranting its consideration for cultivation and inclusion in breeding programs aimed at varietal development.