Major California processing tomato cultivars respond differently in yield and fruit quality to various levels of moisture stress

Agriculture water cost and availability are an increasing problem in arid agriculture including processing tomato production worldwide. Prior research has shown that preharvest stress has the least effect on reduced yield and results in higher solids than stress during fruit set and early fruit development. This research shows a wide difference in tomato cultivars' ability to deal with preharvest stress and retain high yields and fruit quality with significant water savings. A new Heinz variety, H-9492, yielded equal fruit tonnage and tons of solids with 14 cm less water than H-8892, or 21 cm less water than Bos-3155. The H-8892 and Bos-3155 varieties made up 48% of the processing tomato loads in California in 1997. These two varieties were in the top four varieties in the 1993 to 1995 preharvest stress trials when they were being established as preferred grower and processor varieties. It would appear that a vigorous preharvest moisture stress screening program (the days water is cut off before harvest) to evaluate new varieties' ability to perform under stress would bring these superior varieties onto the market much faster than the present method of evaluation.