This Is AuburnElectronic Theses and Dissertations

The Effects of Polyethylene and Cereal Rye Mulch, Tillage, and Herbicides on Tomato and Watermelon Yield and Weed Control




Williams, Jacob

Type of Degree

Master's Thesis


Crop Soils and Environmental Sciences


Cereal rye, polyethylene mulching, and tillage all have an impact on the yield and growth of weeds. Herbicides have been used to control weed growth for decades. Using these in conjunction can possibly demonstrate ways to reduce reliance on herbicides and reduce herbicide selection pressure. Overuse of herbicides in many systems has led to the development of herbicide resistant weeds. The objective of this project was to examine new ways to suppress weed growth in production systems. In separate studies, tomato and watermelon were grown 2014, 2015, and 2016 near Shorter, AL. The tomato (Solanum lycopersicum L.) and watermelon (Citrullus lanatus (Thunb.) Matsum. & Nakai) studies were laid out in a split-strip design. The main strip was mulching system. Mulching systems used were conservation tillage with Wrens Abruzzi cereal rye (Secale cerale L.) drilled at 100.8 kgs/hectare, conventional tillage that was turned and disked before planting with and without polyethylene mulch, and polyethylene integrated with conservation tillage. The herbicide systems used included 1) halosulfuron (52.5 grams ai ha-1) for tomato; halosulfuron (26.3 grams ai ha-1) for watermelon applied PRE, 2) trifloxysulfuron (10.5 grams ai ha-1) applied POST in tomato; halosulfuron (26.3 grams ai ha-1) applied POST in watermelon, 3) a combination of PRE and POST, and 4) a non-treated control arranged in a full factorial. Use of polyethylene mulch significantly increased tomato yield over conventional tillage and conservation tillage without polyethylene. The effect of polyethylene can also be seen in the herbicide interaction. Herbicides were much less effective at increasing yield and controlling weeds compared to use of polyethylene. Weed control ratings revealed similar results, with treatments that included polyethylene having higher weed control. In watermelon, yield was also significantly increased by the use of polyethylene mulch, similar to that observed in tomato. Weeds were also controlled under polyethylene mulch similar to that measured with tomato.