|Damicone, J. P.|
Submitted to: Subtropical Plant Science
Publication Type: Review Article
Publication Acceptance Date: 8/19/1999
Publication Date: N/A
Interpretive Summary: Fusarium wilt is a constant threat to watermelon production around the world. Three races of the fungus are presently recognized. Only cultivars that have no resistance genes are affected by race 0. Highly resistant cultivars, in conjunction with rotation, provide good control of race 1, which is the predominant race in most watermelon production areas. There is no acceptable level of resistance to race 2 in commercial watermelon cultivars. We have reviewed the literature on Fusarium wilt of watermelon and presented information on the potential threat of race 2 to the watermelon industry in Texas and Oklahoma. Seedless watermelon cultivars are, for the most part, very susceptible to Fusarium wilt. With the increased emphasis on seedless watermelon production, the possibility that Fusarium wilt will again become a yield- limiting disease is a serious concern. Additional research is needed to establish the distribution of race 2 and the frequency of all three races within the watermelon production areas of Texas and Oklahoma. Furthermore, an integrated strategy for effective management of Fusarium wilt using highly resistant cultivars, proper plant nutrition, rotation, and biocontrol must be developed.
Technical Abstract: Fusarium wilt remains a constant threat to watermelon production in Texas and Oklahoma. Highly resistant cultivars, in conjunction with rotation, have provided good control to race 1 of F. oxysporum f. sp. niveum which is widespread in Texas and Oklahoma watermelon production areas. Race 2, for which there is no acceptable level of resistance in commercial cultivars, does not appear to be widespread within the major watermelon production areas. Additional research is needed to establish the distribution of race 2 and frequency of the three existing races (races 0, 1, and 2). A "Universal Testing System" for evaluating germplasm and monitoring virulence shifts in the pathogen population is essential. An integrated strategy for effective management of races 1 and 2 of the Fusarium wilt fungus must be devised and implemented using crop rotation, cultural management, and highly resistant cultivars.