|Michel, Vincent - AVRDC|
|Midmore, David - QUEENSLAND UNIVERSITY|
Submitted to: Plant Disease
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: October 21, 1996
Publication Date: N/A
Interpretive Summary: Bacterial wilt, caused by Pseudomonas solanacearum, is a major soilborne disease of tomato in more tropical and subtropical regions of the world including Florida. Host resistance to bacterial wilt has been incorporated into some tomato hybrids with some success, although host resistance alone often is not enough to control bacterial wilt. Cultural controls practices, including various crop rotations have been used in an overall management scheme to control bacterial wilt. Three field experiments were conducted to evaluate the control of tomato bacterial wilt following soil fallow, and following crops of cowpea, eggplant, and rice. Bacterial populations in the soil declined after growing cowpea and rice, but not after growing eggplant. The incidence of wilted tomato plants was less following cowpea and rice than when tomato followed eggplant in the rotation for three experiments. In addition, tomato yields swere lower following eggplant than rice in the rotation. The research results in this paper complements other research on control of this important disease of tomato. It provides the basis for more studies on developing integrated management practices including host resistance and crop rotation to control bacterial wilt.
Technical Abstract: Three field experiments were conducted to evaluate populations of Pseudomonas solanacearum and the occurrence of tomato bacterial wilt following soil fallow, and crops of cowpea, eggplant, and rice. Bacterial population declined after cowpea and rice, but not after eggplant. The population also declined after leaving soil fallow indicating that a suitable host plant helps maintain the bacterial population. The area under disease progress curve (AUDPC), based on the incidence of wilted tomato plants, was significantly (P < 0.05) higher following eggplant compared to cowpea and rice for three experiments and in fallow for two experiments. Yields of cowpea, eggplant, and rice were not affected by the presence of the P. solanacearum in the soil; however, yields of the following tomato crops were significantly (P < 0.05) lower following eggplant than following rice. Under greenhouse conditions, bacterial populations decreased greater when soil was cropped to rice under permanently flooded conditions.