Under heavy pressure to prolong the life of landfills, cities have been asked to reduce the amount of trash deposited in them. Yard grass clippings and prunings contribute greatly to filling up local land fills. Since green waste can be easily composted, municipalities are looking into agriculture as a potential candidate in disposing of composted material. It is common knowledge that compost is good for plants. However, most information seems to be anecdotal or testimonial. Therefore, the need for scientific-based information is highly needed if compost is to be used successfully in agricultural lands. To generate hard data, replicated test plots were conducted in watermelons, sweet corn, and tomatoes in which 10 and 20 tons per acre of community-derived, green waste, composted material was used in addition to a commercial fertilizer rate and nontreated check. Soil and tissue analyses were run three times during the season to check nutrients in plants(N, P, and K). Organic matter, electrical conductivity, and pH were analyzed from soil samples. Yields and quality determinations also were taken from all crops for comparisons. Organic matter from compost treatments increased significantly in corn and tomatoes. Electrical conductivity was lower in the composted treatments, and K increased as well. Trials are being funded by the California Integrated Waste Management Board, and it will continue for at lease 1 more year.
Jesús Valencia and Donald M. May
An irrigation water study was conducted in the West side of Fresno County to evaluate the impact of recycled drainage water nitrogen and salinity content in the growth of direct seeded processing tomatoes to reduce nitrate-ground water pollution. Four canal water treatments (0.4 dS/m) received 0, 67.5, 101.2, and 168.7 kg of nitrogen per hectare and four saline water treatments (7.01 dS/m) received 0, 33.7, 67.5 and 135.0 kg nitrogen per hectare. All treatments were established with fresh canal water, and at first flower half of treatments were switched to saline water. The nitrogen content of water had an average of 283 ppm N-NO3 for the canal water and the drainage water contained 4489 ppm N-NO3. There was no significant yield differences between the irrigation methods and the two N-fertilizer sources applied to the tomatoes. However, drainage water produced a significant increase in fruit soluble solids (5.05 Av.) in comparison to canal water and synthetic fertilizer (4.3 Av.). The overall fruit quality and maturity was better in the drainage water treatments than it was in the fresh canal water with synthetic N-applied treatments.
Mike Murray, Mike Cahn, Janet Caprile, Don May, Gene Miyao, Bob Mullen, Jesus Valencia, and Bill Weir
University of California Cooperative Extension farm advisors have conducted applied research to quantify processing tomato [Lycopersicum esculentum (L.) Mill] varietal performance, as a coordinated activity, since 1973. Early and midseason maturity varieties are annually evaluated at four to six locations throughout the state. The test varieties are selected in collaboration with seed companies, processors and growers. The growers and seed companies provide financial support for the tests. Most tests are conducted in production tomato fields and are harvested using commercial harvesters. The results are widely disseminated through an annual report to the funding sources, farm advisor research reports, newsletters, production meetings, the California Tomato Grower magazine, and popular media. The information obtained for fruit yield potential, fruit quality and plant horticultural characteristics is used by processors, growers, and seed companies to make variety selection decisions. This regional extension program has proven to be an effective way to generate well-designed replicated information for making intelligent processing tomato cultivar decisions and has been well accepted by the California industry.