Paclobutrazol and benzylaminopurine improve potato yield grown under high temperatures in lowland and medium land

Abstract

Abstract Potato is one of the most important vegetable crops in the world. In a tropical country such as Indonesia, potato is cultivated in highland that has low temperature. However, the extensification and intensification of potato cultivation cause environmental problems in the highland. Soil erosion is one of the common problems resulting from potato cultivation that applies heavy tillage. To prevent environmental problems, the land expansion for potato cultivation is carried out in both the medium and lowland. High temperature in both medium and lowland results in the limitation of plant growth and yield. Therefore, the present study aimed to evaluate the effect of plant growth regulators (PGRs), namely paclobutrazol and benzylaminopurine (BAP) application on the growth and yield of potatoes grown under high temperature in both lowland and medium land. A split-plot design was used in this experiment with the main plot as growing altitude, i.e., low and medium land, and the PGR treatments as the subplot, i.e., control, paclobutrazol at 100 mg L−1, BAP at 50 mg L−1, and a combination of paclobutrazol at 100 mg L−1 and BAP at 100 mg L−1. The result showed a reduction in plant growth and yield in potatoes grown in lowland compared to those in medium land. The application of paclobutrazol and BAP improved the number, the weight of tuber, and its starch content. The result indicated that the application of paclobutrazol and BAP could be used to solve an environmental limitation for potato cultivation in both lowland and medium land.