Thitisilp Kijchavengkul¹, Rafael Auras¹*, Maria Rubino¹, Mathieu Ngouajio², R. Thomas Fernandez^2
1School of Packaging, Packaging Building
²Department of Horticulture, Plant & Soil Science Building
Michigan State University, East Lansing, MI 48824- 1223 E: aurasraf@msu.edu

Abstract. The objective of this work was to determine the requirements for successful mulching of new biodegradable mulch films under open field vegetable production. The biodegradable mulch films were made from modified poly (butylene adipate-co-terephthalate) and included two colors (black and white) and two thicknesses (25 and 35 microns). A conventional black low density polyethylene (LDPE) mulch film (25 micros) was included as control. The films were used to produce tomato using raised beds and drip irrigation during two growing seasons. Changes in physical appearance, mechanical, optical and physical properties were measured and recorded. After tomato harvest, the conventional LDPE mulch film was removed and all the biodegradable mulch films were plowed into the soil. Samples of each film after plowing were taken and characterized regarding the properties mentioned above and the presence of the biodegradable mulches was assessed the following spring. Early in the season, all the biodegradable films showed significant photodegradation and developed crosslink structures within the films, which promoted brittleness. The white films degraded much faster than the black mulch due to several factors including higher photodegradation and the inferior ability to suppress weed growth allowing weeds to protrude through and tear the films. Based on the parameters measured, the black biodegradable film has potential as a promising alternative to conventional mulch film because of the lower reduction of the tensile strength and no changes in the light transmission; besides, small amount of residues from the first season films were found during the second season site preparation.

There is no full paper associated with this abstract.