Bio-based Sprayable Mulch for Weed Control in Row Crop Systems

Authors

Camila Chiaranda Rodrigues, University of Nebraska-LincolnFollow

First Advisor

Christopher A. Proctor

Date of this Version

11-2024

Document Type

Thesis

Citation

A thesis presented to the faculty of the Graduate College at the University of Nebraska in partial fulfillment of requirements for the degree of Master of Science

Major: Agronomy

Under the supervision of Professor Christopher A. Proctor

Lincoln, Nebraska, November 2024

Comments

Copyright 2024, Camila Chiaranda Rodrigues. Used by permission

Abstract

Improving current crop productivity levels requires transformative advancements in management, engineering, and science. One of the main challenges is the increasing difficulty of weed management due to herbicide-resistant weeds. There is a growing need for alternative weed management methods to reduce pesticide use and improve environmental safety. An emerging technology that is being developed is spray-on films which could help address these challenges. Spray-on films are liquid solutions that after spraying on the soil will dry and form a physical barrier. The overall objective of this research was to evaluate the effectiveness of a chicken feather bio-based sprayable mulch film (biofilm) on reducing weed emergence without interfering with the crop development. Multiple studies were conducted under greenhouse and field conditions in Nebraska. Research studies were focused on assessing biofilm dose-responses across a range of application rates (0.2 to 16 L m^-2). To understand the effect of biofilm application timing and placement studies were conducted testing three different application timings relative to crop growth stage (pre-emergence, VC, and V2) and the impact of broadcast versus banded spray application placement. It was found that each weed species requires a different rate to achieve at least 90% control. Notably, higher rates were necessary under field conditions compared to the greenhouse for effective weed suppression. In greenhouse conditions, all weeds tested achieved 90% of control with the rate equal to or below 4.8 L m^-2 and above the highest rate tested (16 L m^-2) in the field. In a field row-crop system, biofilm banded application will not interfere crop development. The conclusion is that there isn’t one rate that results in high weed suppression without crop injury. For application timing pre and post (VC and V2) can be used with the appropriate rate depending on target species. Banded application is preferred in row-crop systems to avoid crop injury. Variables such as soil microbiology and nutrients impact still require further investigation.

Advisor: Christopher A. Proctor