Conservation management practices influence soil microbial communities regardless of irrigation in Sandy loam cotton systems of the semi-arid Texas Southern High Plains

Authors: PETERMANN, BILLI - Texas Tech University; LEWIS, KATIE - Texas Tech University; Acosta-Martinez, Veronica; LAZA, HAYDEE - Texas Tech University; STEFFAM, JOSHUA - Dickinson State University; SLUAGHTER, LINDSEY - Texas Tech University

Submitted to: ASA-CSSA-SSSA Annual Meeting Abstracts
Publication Type: Abstract Only
Publication Acceptance Date: 10/18/2022
Publication Date: 11/7/2022
Citation: Petermann, B., Lewis, K., Acosta Martinez, V., Laza, H., Steffam, J.J., Sluaghter, L. 2022. Conservation management practices influence soil microbial communities regardless of irrigation in Sandy loam cotton systems of the semi-arid Texas Southern High Plains. ASA-CSSA-SSSA Annual Meeting Abstracts.

Interpretive Summary:

Technical Abstract: Agricultural producers in semi-arid regions such as the Texas Southern High Plains (SHP) face many challenges while attempting to increase soil health and profitability, particularly severe water and nutrient scarcity. Cotton production in the Texas SHP has historically relied on continuous cropping, tillage, and irrigation to sustain productivity, but declining groundwater resources have prompted a greater focus on conservation practices such as cover crops, crop rotations, and conservation tillage to improve soil health and water storage. Soil microbial community size and composition drive many functions that influence plant productivity, such as nutrient cycling, improved soil structure, and subsequent water dynamics, making them important indicators that can be used to assess soil health improvements. Soil samples were taken from two depths (0-10 cm, 10-20 cm) and from the root zone for two years at a fine sandy loam site in this region under three long-term (> 10 years) cotton management strategies, each under high and low irrigation: 1) Continuous monocrop with conventional tillage, 2) reduced tillage with rye cover crop, and 3) reduced tillage with a cotton/wheat rotation. The microbial communities among these systems were compared in terms of size (via ester linked-fatty acid methyl esters analysis), diversity (via amplicon sequencing), and C and N-cycling activities (via high-throughput fluorometric assays of extracellular enzymes). Our results revealed management-induced differences in soil microbial communities regardless of irrigation level, suggesting that conservation practices such as reduced tillage and diversified planting can improve soil health in coarse-textured soils in this semi-arid region.