ASSOCIATION OF ENVIRONMENTAL CONDITIONS WITH GUMMY STEM BLIGHT AND BLACK ROT EPIDEMICS OF MUSKMELON IN OKLAHOMA AND TEXAS

Authors: Bruton, Benny; Zhang, Jiuxu; MILLER, M. - TEXAS A&M UNIV.; ISAKEIT, T. - TEXAS A&M UNIV.

Submitted to: Oklahoma Horticulture Industry Proceedings
Publication Type: Proceedings
Publication Acceptance Date: 1/9/1998
Publication Date: N/A
Citation: N/A

Interpretive Summary: Fruit rot of cantaloupe causes economic losses in many production areas. Black rot of cantaloupe, caused by the gummy stem blight fungus, is rarely a problem in cantaloupe. Consequently, the conditions necessary for infection and the resulting symptoms associated with the disease have not been adequately described. We have identified some of the environmental conditions necessary for infection of cantaloupe fruit and provided a description of symptoms. Cantaloupe fruit are very susceptible to infection between about 12 to 25 days after fruit-set. This corresponds to splitting of the epidermis and beginning stage of net development. During the summer of 1996, rain occurred on seven consecutive days at Lane, Oklahoma when the fruit were approximately twenty-five days old. In addition, the temperatures were relatively cool in the range of 25 deg C which are conducive to infection by the black rot fungus. Cantaloupe frui mature at about forty days after fruit-set. A high percentage of the fruit exhibited black rot at harvest. A similar situation occurred in the Rio Grande Valley of Texas in the spring of 1997. Cantaloupe were severely affected by infection by the black rot fungus causing millions of dollars in losses. This is the first reported case of catastrophic losses due to the black rot fungus on cantaloupe.

Technical Abstract: Environmental conditions interacting with a specific fruit development stage can result in severe infection of cantaloupe fruit by a number of fungi. Cantaloupe fruit are very susceptible to infection between about 12 to 25 days after fruit-set. This corresponds to splitting of the epidermis and beginning at the stage of net development. During the summer of 1996, rain occurred on seven consecutive days at Lane, Oklahoma when the fruit were approximately twenty-five days old. In addition, the temperatures were relatively cool in the range of 25 deg C which are conducive to infection by the black rot fungus. Cantaloupe fruit mature at about forty days after fruit-set. A high percentage of the fruit exhibited black rot at harvest. A similar situation occurred in the Rio Grande Valley of Texas in the spring of 1997. Cantaloupe were severely affected by infection by the black rot fungus causing millions of dollars in losses. This is the first reported case of catastrophic losses due to the black rot fungus on cantaloupe.