EVALUATION OF THE INITIAL SEASON FOR IMPLEMENTATION OF 4 TOMATO PRODUCTION SYSTEMS

During the initial season of implementation, four tomato production sy stems differing in soil management, pest control practices, and level of inputs, such as labor, materials, and management intensity were eva luated, These systems were CON, a low input (no mulch, no trellising, overhead irrigation, preplant fertilization, scheduled pest control), conventional agrichemical system; BLD, a high input [straw mulch, trel lising, trickle irrigation, compost fertility amendment, integrated pe st management (IPM)], ecologically-oriented system that emphasized the building up of soil organic matter levels and used no agrichemicals t o supply fertility or for pest control; BLD+, a system similar to BLD, except that agrichemical pesticides were used; and ICM, a high input system (blackpolyethylene mulch, trellising, trickle irrigation, ferti gation,IPM pest control) that used agrichemicals to supply fertility a nd for pest control. Soil characteristics and fertility levels in the BLD and BLD+ systems were modified with extensive amendments of spent mushroom compost and well-rotted cattle manure. Levels of agrichemical NPK calculated to meet current crop needs were supplied to the CON an d ICM systems, with 75 % of fertility in the ICM system supplied throu gh the trickle irrigation lines (fertigation). The BLD system had a gr eater soil water holding capacity and sharply reduced irrigation requi rements. During a wet period, fruit cracking and evidence of water-mol d root rot were significantly higher in the ICM system than the BLD an d CON systems. Defoliation by Alternaria solani was greatest in the BL D system and least in the ICM system. The BLD and ICM systems resulted in a 1 week earlier peak yield compared to the CON system. The yield of No. 1 fruit was 55% to 60% greater in the BLD+ system than the othe r three systems, which were comparable in yield. Net return was highes t in the BLD+ system, although the benefit/cost ratio was greatest in the CON system. This multidisciplinary study has identified important differences in the performance of diverse production systems during th e unique transitional season.