DEVELOPMENT OF A POLYETHYLENE MULCH SYSTEM THAT CHANGES COLOR IN THE FIELD

A polyethylene mulch system that changes its predominant surface color from black to white in the field has been developed and used to grow tomatoes (Lycopersicon esculentum Mill. cv. Mountain Pride) and squash [Cucurbita pepo var. melopepo (L,) Alef. cv. Dixie Hybrid]. The syste m uses a black photodegradable polyethylene mulch placed on top of a w hite nondegradable polyethylene mulch (photodegradable mulch overlay s ystem), As the black photodegradable mulch degrades with increasing ex posure to radiation, the white mulch surface is exposed, Differences a mong plastic systems in the percentage that breaks down may be explain ed by differential shading of the mulch by the vegetative growth of th e crops, None of the formulations of the Plastigone brand photodegrada ble mulches in the photodegradable mulch overlay system had an effect on tomato or squash production, As the color of the system changed fro m black to white, soil temperatures under the mulch decreased, Tomato production remained unaffected in one of the two years as long as the mulch remained black for at least the first 20 days during that season . In year 2, the controlled mulch system color change affected neither tomato nor squash production relative to nondegradable white and blac k mulches used as controls.