Abstract
Field studies were conducted to determine the effect of water management regimes on tomato (Solanum lycopersicum L.) production, and assess the effect of highly-retentive mulches and methyl bromide alternatives on the water volumes necessary for tomato irrigation. Twelve treatments resulted from combinations of fumigant and mulches, and irrigation programs. The combinations of fumigants and mulches were: 1) methyl bromide + chloropicrin (67:33 v/v) at a rate of 175 lb/acre under metalized mulch; 2) 1,3-dichloropropene + chloropicrin (65:35 v/v) at 16 gal/acre under metalized mulch; and 3) 1,3-dichloropropene + chloropicrin (65:35 v/v) at 32 gal/acre under high-density polyethylene mulch. The irrigation programs were seepage (subsurface) irrigation alone at 20 and 40 acre-inches/acre per season, and the same seepage irrigation volumes combined with a drip irrigation volume of 14 acre-inches/acre per season. Increasing seepage volume from 20 to 40 acre-inches/acre in combination with drip irrigation did not increase average soil moisture, ranging between 9.0% and 10.3%. In contrast, irrigation volumes had an effect on soil moisture when only seepage irrigation was provided, with values increasing from 9.4% to 11.9% when water volumes increased from 20 to 40 acre-inches/acre, respectively. Only the irrigation programs had significant effects on total marketable fruit weight. Adding drip irrigation to seepage-treated plots had a positive effect on fruit weight, increasing yields from 15.9 ton/acre in plots with only seepage to 17.6 ton/acre. Increasing seepage irrigation from 20 to 40 acre-inches/acre in plots under drip irrigation improved yields from 15.4 to 19.8 ton/acre. However, increasing seepage volumes in plots without drip irrigation had no effects on tomato total marketable yields
