The effect of palm oil (Elaeis guineensis Jacq) solid waste on the stomatal density and chlorophyll content of the pepper (Piper nigrum L. )

Abstract

This study investigates the impact of palm oil (Elaeis guineensis Jacq) solid waste on stomatal density and chlorophyll content in pepper plants (Piper nigrum L.). Employing a Randomized Block Design (RBD) comprising four treatments and five replications, the research used the mixed of the waste and soil with the ratios: P0 (1 kg soil, control), P1 (333 g palm oil solid waste and 666 g soil, 1:2 ratio), P2 (500 g soil and 500 g palm oil solid waste, 1:1 ratio), and P3 (666 g palm oil solid waste and 333 g soil, 2:1 ratio). Our findings indicate that the stomatal density in the adaxial part of pepper's leaves was highest in treatment P2, whereas stomatal density in the abaxial part was highest in treatment P3. Additionally, the highest chlorophyll a content was observed in treatment P2, while chlorophyll b and total chlorophyll content were highest in treatment P3. These results underscore the complex interplay between waste composition and plant physiological responses.