Agronomic Traits and Physiology of Maize at Various Levels of Water Application

Abstract

Maize cultivation in Gorontalo Regency is commonly done in dry land, and this has made water as the main limiting factor for the excellent growth of the plant, as the plant often experiences water stress. This study was conducted to examine the agronomy traits and physiology of hybrid and composite maize on various water application levels. The study was done using a Split Plot Design in each with three repetitions. The main plots were for four different levels of water application: without water (A₀), once water application (A₁), twice water application (A₂), and three-time water application (A₃). The sub-plots were for the maize varieties, which consisted of two levels namely hybrid maize variety Bisi-2 (V₁) and composite maize variety Bisma (V₂). The results of the study show that three-time water application has helped increasing the height of the plants, the dry weight of the plants, as well as the dry weight of grains. Plants without water supply showed a decrease in the dry weight of the grains as much as 36% compared to the plants with three-time water application. Three-time water application method on Bisi-2 variety showed the highest result and no water application on Bisma variety showed the lowest result. Water stress has caused production of Bisma variety 22% lower than Bisi-2 variety. The physiology analyses show that CO₂ intercellular on Bisma variety is higher than Bisi-2 variety, yet the rate of photosynthesis, transpiration, and water efficiency on both Bisma and Bisi-2 variety are not different.

Key words: water application, variety, photosynthesis