This Is AuburnElectronic Theses and Dissertations

Combinations of soil dimpling and mulch type to reduce nutsedge (Cyperus spp.) punctures in polyethylene mulched beds




Boatwright, Logan

Type of Degree

Master's Thesis




Growers use polyethylene (PE) mulch to maximize vegetable crop yields. Specifically, PE mulch provides earlier and higher yields, a cleaner and higher quality product, a more economical use of water and fertilizers, along with improved disease, insect, and weed control. Conversely, not all weed species are significantly controlled. Two of the most economically damaging weeds, yellow (C. esculentus) and purple (C. rotundus) nutsedge, can readily pierce and degrade PE mulch allowing competition with vegetable crops. While field research has been limited, different types of PE mulches have been assessed for controlling and altering growth of nutsedge. Results from these previous evaluations showed encouraging results prompting our research objectives. The reduction efficacy of yellow and purple nutsedge punctures in PE mulched beds were evaluated using combinations of mulch type and soil dimpling. Yellow and purple nutsedge were evaluated separately at two different locations. Both experiments were setup as an augmented factorial treatment arrangement of two mulch types (white or infrared-transmitting (IRT) green) and three dimple sizes (none, small, and large). This was augmented by a commercial standard (white mulch with a preemergence (PRE) herbicide applied under mulch), giving a total of 7 treatments. Treatments were evaluated based on their ability to decrease nutsedge punctures. For the yellow nutsedge study, the main effects for mulch were significant; however, the main effects of dimples and the interaction between mulch and dimples were not significant for any response variables (punctures and weight of emerged and non-emerged shoots). Yellow nutsedge punctures 14, 28, and 60 days after treatment (DAT), dry weight of emerged and non-emerged yellow nutsedge shoots were reduced significantly by IRT-green PE mulch compared to white mulch and the standard treatment. Data for the purple nutsedge study were similar. Interactions of mulch x dimple treatments were not significant for any response variables; therefore, main effects were analyzed. Main effects for mulch and dimples (14 DAT only) were significant, therefore means were compared. Nutsedge punctures were significantly reduced in infrared mulch treatments compared to white mulch treatments and the standard treatment at all rating dates. Additionally, dry weight of emerged and non-emerged shoots were reduced in infrared mulch treatments compared to white mulch treatments and the standard treatment The aforementioned results suggest that IRT-green PE mulch may suppress yellow and purple nutsedge populations regardless of dimples in PE mulched beds and successively reduce the impact on yield and quality of vegetable crops.