Effect of Different Levels of Nitrogen and Planting Patterns on Dry Matter Production and Growth Physiological Indices in Intercropping Maize and Sunflower

Abstract

This research aimed at investigating the effect of different levels of nitrogen and planting patterns on dry matter production and growth physiological indices in intercropping maize and sunflower. To do this a split plot experiment carried out based randomized complete block design with three replications in research field of Shushtar Islamic Azad University. The main plot included three levels of nitrogen as N₁=50, N₂=100, and N₃=150 kg.ha^-1 nitrogen and the sub plot included two crops monoculture (S₁=Sunflower, S₅=Maize) and three planting patterns (S₂=25% Maize + 75% Sunflower, S₃= 50% Maize + 50% Sunflower, S₄= 75% Maize + 25% Sunflower). The mixture was formed based on replacement. Result revealed that the increase of nitrogen level up to 150 kg.ha^-1 significantly increased plant height and total fresh weight of maize and sunflower. Planting pattern influenced maize plant height and total fresh weight of maize and sunflower. The highest TDM, height, and total fresh weight of maize and LAI and total fresh weight of sunflower belonged to the second planting pattern. Result also showed that CGR, RGR, and NAR in each plant followed the general pattern of these indices and the best status was achieved at the level of 150 kg.ha^-1 nitrogen. The highest rate of LER by 1.16 belonged to N₃S₂. That is, the intercropping yield in this case increased 16% compared with pure cultivation.