Effect of crop management and weed control systems on the native soil microbial population

Dip Majumder,Manabendra Ray,Dilip Kumar Khan

doi:10.52756/ijerr.2020.v21.001

Abstract

The soil quality in a paddy field is the most crucial element for the supply and the production of rice in India. However, the pressure on the paddy field creates a challenge for preventing soil degradation. Soil microflora are most vulnerable to soil pollution, and a decrease or increase of the soil bacteria may reflect the health of soil. In this study, we try to understand the effect of crop management and weed control systems on the native soil bacterial colony. Our study consists of three types of crop management systems, such as zero-tillage, the system of rice intensification (SRI), brown manuring, and three types of weed removal processes, i.e. chemical, integrated and mechanical. In the chemical and integrated treatment, two herbicides were used for weed removal, but in mechanical weeding, a conoweeder was used. The colony forming unit (CFU) of different soil bacteria (nitrogen fixing and phosphate solubilizing) were measured during different stages of the crop growth. It was observed that the mechanical weeding has the least impact for both soil bacteria, but the chemical treatment showed a decrease of PSB count in all three systems. Whereas, the integrated treatment produced a better result in crop management and soil microbial population.

Highlights

Indigenous microbial population of soil is important for maintenance of soil quality
The bacterial population was increased by 15% after mechanical weeding
After second time application of herbicide, Azotobacter bacterial population reduced for the chemical treatment up to 25%, but it reduced for the integrated treatment up to 15% (Figure 1a)

Summary

Introduction

Indigenous microbial population of soil is important for maintenance of soil quality They regulate numerous factors such as - organic content, nutrient cycling, soil aeration, and amount of available nitrogen. They influence the growth of the plant through different processes, rhizosphere activity, legume activity, releasing of organic acids, and soil binding are few of them. The large root system and the diverse number of microorganisms are the main two major factors, which play a crucial role in the SRI. These two interacting factors create a bigger nutrient-based network containing mites, earthworms, arthropods, and other organisms. Substituting the conventional flooding process, these two soil moisture methods provide an advantage for the root-growth and soil aeration (Thakur, 2010)

Methods

Results

Conclusion