In 2004, cucurbit downy mildew re-emerged in the US with a vengeance causing significant losses in cucurbit production. In most years prior to this, concern for CDM control was minimal, since the pathogen arrived late in the growing season (in more northern regions), or the pathogen caused little damage, or never appeared. After 2004, with significant losses at stake, and with very few fungicides labeled for its proper control, CDM became a serious threat to cucurbit production. Importantly, at the time, cucumber varieties with very good levels of CDM resistance were no longer resistant, suggesting a major shift in the pathogen population. Research done over the past 19 years has led to a better understanding of the pathogen. Recent research has determined that the CDM falls into two separate clades: Clade I and Clade II. [Read more…]
Cucurbit Downy Mildew Alert – Cucumber – 6/11/22
Cucurbit downy mildew has been confirmed on cucumber in southern New Jersey. This is the first report of CDM in the state and region this growing season. All cucumber and cantaloupe growers should scout on a daily basis and initiate a preventative fungicide program. CDM was last confirmed on June 1 on cucumber in central North Carolina and on watermelon on June 9 in south central Georgia. Remember, some CDM isolates fall into Clade I which predominately infect watermelon, pumpkin, and squash, where other CDM isolates in Clade II predominately infect cucumber and cantaloupe.
For more information on CDM, the clades, and CDM control please click here.
![](https://plant-pest-advisory.rutgers.edu/wp-content/uploads/2022/06/CDM-2022-300x142.jpg)
Cucurbit downy mildew sporulating on the underside of an infected cucumber leaf.
Cucurbit Downy Mildew Alert – Pumpkin – 8/27/21
Cucurbit downy mildew has been confirmed on pumpkin in Morris County, New Jersey. This is the first report of CDM on pumpkin in the state and region this growing season. CDM was confirmed on cucumber and cantaloupe earlier this summer. Growers should scout all cucurbit crops on a daily basis and initiate a preventative fungicide program. Remember, some CDM isolates fall into Clade II which predominately infect cucumber and cantaloupe, where Clade I isolates predominately infect watermelon, pumpkin, and squash.
For more information on CDM, the clades, and CDM control please click here.
Cucurbit Downy Mildew Alert – Cantaloupe – 6/22/21
Cucurbit downy mildew has been confirmed on cantaloupe in southern New Jersey. This is the first report of CDM on cantaloupe and the second this growing season. CDM was confirmed on cucumber on 6/16/21. All cucumber and cantaloupe growers should scout on a daily basis and initiate a preventative fungicide program. CDM has also been confirmed on cucumber in Ontario, Canada this week. Remember, some CDM isolates fall into Clade I which predominately infect watermelon, pumpkin, and squash, where other CDM isolates in Clade II predominately infect cucumber and cantaloupe.
For more information on CDM, the clades, and CDM control please click here.
Cucurbit Downy Mildew Alert – Cucumber – 6/16/21
Cucurbit downy mildew has been confirmed on cucumber in southern New Jersey. This is the first report of CDM in the state and region this growing season. All cucumber and cantaloupe growers should scout on a daily basis and initiate a preventative fungicide program. CDM has also been confirmed on cucumber in Ontario, Canada this week. Remember, some CDM isolates fall into Clade I which predominately infect watermelon, pumpkin, and squash, where other CDM isolates in Clade II predominately infect cucumber and cantaloupe.
For more information on CDM, the clades, and CDM control please click here.
Cucurbit Downy Mildew Alert – 6/16/21
Cucurbit downy mildew has been confirmed on cucumber in southern New Jersey. This is the first report of CDM in the state and region this growing season. All cucumber and cantaloupe growers should scout on a daily basis and initiate a preventative fungicide program. Remember, some CDM isolates fall into Clade I which predominately infect watermelon, pumpkin, and squash, where other CDM isolates in Clade II predominately infect cucumber and cantaloupe.
For more information on CDM, the clades, and CDM control please click here.