|Abdul Baki, Aref|
Submitted to: Proceedings of Florida State Horticultural Society
Publication Type: Proceedings
Publication Acceptance Date: 8/26/2003
Publication Date: 10/1/2003
Citation: Wang, Q., Bryan, H., Klassen, W., Li, Y., Codallo, M. Wang, Q., Bryan, H., and A. Abdul Baki. Klassen, W., Li, Y., Codallo, M. 2002. Improved tomato production with summer cover crops and reduced irrigation rates. Florida State Horticultural Society. 115:202-207.
Interpretive Summary: Conventionally, winter production of fresh-market tomatoes is preceded witheither fallow or sorghum Sudangrass, neither of which fix nitrogen. We introduced three legume cover crops, sunn hemp, velvetbean and cowpea, that fix nitrogen and reduce nitrogen input from commercial fertilizers. We also reduced the irrigation rate after noticing that growers are over watering. The combination of using the legume cover crops and reducing watering by about 50% resulted in net savings on fertilizer and water as well as in yield increase and reduction in fruit decay.
Technical Abstract: A tomato production system for Florida that lowers the cost of production per carton, and does not require soil fumigation is being developed. To identify the most suitable cover crops and optimum irrigation management for tomatoes, a field experiment was conducted in 2001-2-2 with three legume cover crops [sunn hemp (Crotalaria juncea), cowpea (Vigna unguiculata) and velvetbean (Mucuna deeringiana)], 1 non-legume cover crop [sorghum Sudangrass (Sorghum bicolor x S. bicolor)], clean fallow, and 4 irigation rates: 5, 10, 20 and 30 cbar. The cover crops were planted on May 9, 2001. Two months later the sunn hemp was mowed at 30-cm above the ground to promote branching, and the cowpea was flail-mowed at ground level and reseeded. During the first week of October 2001, all of the cover crops were flail-mowed and incorporated into the soil. Each bed was provided with two drip lines and covered with plastic mulch. Tomato seedlings were planted during the 3rd week of October. The dry weights (Mt/ha) of biomass returned to the soil were as follows: sunn hemp, 13.7; velvetbean, 11.0; cowpea, 12.0; and sorghum Sudangrass, 5.3. The corresponding tomato total fruit yields (Mt/ha) were: 61.3, 59.7, 51.0, 58.9, respectively, and 54.8 from the fallow treatment. The tomato fruit yields were significantly greater with soil water tension maintained near 30 than near 5 cbar. Water use near 30 cbar, was 70% less than near 5 cbar. Thus he use of sunn hemp and velvetbean and reduced levels of irrigation can significantly increase tomato yields and reduce water requirements.