Increasing Yield of Tomatoes with Plastic Mulch and Apex Removal

Abstract

Abstract Field and greenhouse experiments were conducted to encourage growth of basal branches of tomato (Lycopersicon esculentum Mill.) through apex removal and use of plastic mulch. In the greenhouse experiment, apex removal (topping) delayed anthesis of the first flowers by 6 days, but then the faster branch growth increased flower cluster numbers more rapidly on topped plants than on untopped plants. In the first field experiment, apex removal and clear plastic mulch stimulated basal branching and led to a 25% increase in yields of the first four harvests, with the combination of treatments having additive effects. Mulching increased leaf concentrations of P, K, Ca, and NO3-N and decreased Na concentrations, whereas topping increased Ca, Mg, and Na concentrations in leaves sampled 24 days after transplanting. In 1985, mulching resulted in a 54% increase in early yields, but topping depressed marketable early yields by 20% because of fasciation (“catfacing”). In 1985, early yield of an early processing line was stimulated more by mulch than were two later-flowering fresh-market cultivars.