Improving Autumn maize performance by integrated management of Nitrogen form and Herbicide timing

Abstract

Herbicides play a crucial role in agriculture, enhancing crop yield by reducing weed-crop competition. In autumn, maize (Zea mays L.) productivity is 20-25% lower than in spring due to environmental conditions that favor weed infestation and heat stress, which can diminish the efficiency of scarce and expensive inputs like nitrogen fertilizers. Consequently, integrated practices are required for managing input resources. This study aimed to test the integrated management of nitrogen fertilizers and weeds by evaluating different nitrogen forms and herbicide application timings. A dedicated factorial field experiment was conducted in a randomized complete block design at the Renala Khurd research farm, University Sub-Campus Depalpur, Okara, in 2021. Experimental treatments included two N forms (standard urea and neem oil coated urea) at 100% and 75% of the recommended N dose, and two herbicide application timings (pre-emergence and post-emergence) plus a weedy check. Each treatment combination was tested in plots measuring 6 m × 3 m and replicated thrice. Data were statistically analyzed at p=0.05. The findings revealed that the pre-emergence herbicide (s-metolachlor @ 500 ml/acre) along with neem oil coated urea at 75% was the most effective treatment for reducing weed density and maximizing maize yield. This method is thus recommended as an effective and economic way of managing weeds, especially when conventional urea is substantially costlier.