Melons - Diseases

Melons Diseases

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Fusarium Wilt

Charcoal Rot

Monosporascus Root Rot

Fusarium Wilt

Charcoal Rot

Monosporascus Root Rot

Monosporascus vine decline, caused by Monosporascus cannonballus, can be suppressed by application of the fungicide Cannonball at seeding or transplanting followed by additional applications as specified on the product label

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Pythium Sudden Wilt

Pythium, the pathogen that causes this disease, is a fungus-like soil-borne organism that can be managed by fungicides, such as mefenoxam. However, the difficulty in preventing extensive Pythium sudden wilt is that once this disease is initially identified in a field, rapid deployment of an effective fungicide treatment will protect noninfected plants but may not save plants already infected but not yet displaying sudden wilt symptoms.

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Powdery Mildew

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Melon Diseases Publications

Jul 2019

2019 Guidelines for Whitefly / CYSDV Management on Fall Melons

Publication (PDF, 764KB)

Authors: John C. Palumbo

CYSDV has caused significant reductions in fruit yields in the past, mainly due to the whitefly. This article gives some management guidelines for the whitefly including cultural management and chemical management.
Dec 2018

Fall Melon Fields charts 2019

Publication (PDF, 522KB)

Authors: John C. Palumbo

Contains several charts and graphs depicting pressures on fall melons over the last few years.
Jul 2018

2017 Guidelines for Whitefly / CYSDV Management on Fall Melons

Publication (PDF, 656KB)

Authors: John C. Palumbo

CYSDV has caused significant reductions in fruit yields in the past, mainly due to the whitefly. This article gives some management guidelines for the whitefly including cultural management and chemical management.
Jun 2018

Vegetable Diseases Caused by Phytophthora capsici in Arizona

Publication (PDF, 2.27MB)

Authors: Jiahuai Hu

Phytophthora capsici is responsible for some of the most important diseases of peppers and cucurbits worldwide. The diseases are commonly referred to as Phytophthora blight, Phytophthora crown and root rot, Phytophthora fruit rot, and damping of.
Jan 2017

Potential Yield Increase by Grafting for Watermelon Production in Arizona

Publication (PDF, 1.67MB)

Authors: Mark Kroggel and Chieri Kubota

Grafting cucurbits onto rootstocks resistant to diseases and abiotic stresses can be a method to overcome limited availability of effective pre-plant fumigants or land to rotate and to allow earlier planting.
Jul 2016

2016 Guidelines for Whitefly / CYSDV Management on Fall Melons

Publication (PDF, 547KB)

Authors: John C. Palumbo

CYSDV has caused significant reductions in fruit yields in the past, mainly due to the whitefly. This article gives some management guidelines for the whitefly including cultural management and chemical management.
Jul 2015

2015 Guidelines For Whitefly / CYSDV Management on Melons

Publication (PDF, 1.38MB)

Authors: John C. Palumbo

CYSDV has caused significant reductions in fruit yields in the past, mainly due to the whitefly. This article gives some management guidelines for the whitefly including cultural management and chemical management.
Dec 2014

Pest-o-gram: Whitefly transmitted virus of cucurbits 2014

Publication (PDF, 852KB)

A new and potentially damaging whitefly-transmitted virus of cucurbits was found in the fall of 2014. Symptoms include stunting and leaf yellowing.
Dec 2014

Genetic Diversity and Fungicide Sensitivity of Phymatotrichopsis omnivora

Publication (PDF, 383KB)

Authors: Chitrampalam, P. and Olsen, Mary W.

Cotton root rot, caused by Phymatotrichopsis omnivora, is the most destructive disease of dicotyledonous plants in Arizona. There are no known reliable control methods for this disease, and the difficulty in its management is most often directed at its survival deep in soils and its wide host range. Genetic diversity in P. omnivora and its potential role in disease are unknown. Isolating the fungus and reproducing the disease in the greenhouse or laboratory are problematic, making it difficult to assess the efficacy of potential treatments.
Jul 2014

2014 Management of Whiteflies and CYSDV on Fall Melons

Publication (PDF, 328KB)

Authors: John C. Palumbo

CYSDV has caused significant reductions in fruit yields in the past, mainly due to the whitefly. This article gives some management guidelines for the whitefly including cultural management and chemical management.
Feb 2014

Diagnosing Nutrient Deficiencies Quick-Reference

Publication (PDF, 429KB)

Authors: Shawna Loper

Nutrient deficiencies can be identified in field through visual observations. However, additional analysis, either plant or soil testing is often necessary to confirm nutrient stress. The following is a quick-reference flow chart that can be used in field to identify potential nutrient deficiencies. Each nutrient has unique deficiency symptoms. Deficiencies will appear in many ways. It can be confused with other plant problems like pathogens or spray damage. But nutrient deficiencies can often be recognized because they tend to form symmetrical patterns, where both sides of leaf or plant parts show the same pattern.
Jul 2013

Area wide Incidence of Whiteflies and CYSDV In Fall Melons in Yuma County, 2007-2012

Publication (PDF, 1.77MB)

Authors: John C. Palumbo, Kurt Nolte, Yves Carriere

This is a summary of a recently completed project that was designed to survey the area wide incidence of Bemisia whiteflies and Cucurbit Yellow Stunting Disorder Virus (CYSDV) in commercial melon fields throughout the Yuma Arizona growing region.
Jun 2012

2011- 2012 Spring Melon CYSDV Survey

Publication (PDF, 92KB)

Authors: John C. Palumbo

For both the year 2011 and 2012 in the locations of Yuma Valley, Gila Valley, Dome/Wellton, data was gathered into the categories of Total Melon Sites surveyed, Melon acres adjacent to within .25 miles of cotton and the number of sites where CYSDV symptoms were observed.
Jul 2011

Recommendations for Management of Whiteflies, Whitefly-transmitted viruses, and Insecticide Resistance for Production of Cucurbit Crops in Florida

Publication (PDF, 661KB)

Authors: Susan E. Webb, David J. Schuster, P. A. Stansly, Jane E. Polston, Scott Adkins, Carlye Baker, Pamela Roberts, Oscar Liburd, Teresia Nyoike, Eugene McAvoy, and Alicia Whidden

Three viruses transmitted by whiteflies have been identified in watermelon, muskmelon, and squash since 2004. This article outlines some of the signs and symptoms that can be observed.
Jan 2009

Evaluation of fungicide application programs for management of powdery mildew on muskmelon, 2009

Publication (PDF, 40KB)

Authors: M.E. Matheron, M. Porchas

After a few ears of widespread use, some growers have noticed that some fungicides have become less effective. The objective of this field trial was to evaluate disease control efficiency of various fungicide treatment sequences, utilizing products with different modes of action that are registered for use on melon crops.

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Melon Diseases Presentations

Jan 2010

Update on management of Powdery mildew on melons

Presentation (PDF, 2.06MB)

Authors: Michael Matheron

Location Presented: Yuma Agricultural Center
Jun 2008

Vegetable Weed Control in the Desert

Presentation (PDF, 5.58MB)

Authors: Barry Tickes

Location Presented: Yuma Agricultural Center
Sep 2003

Review of Current and Potential Management Tools for Powdery Mildew on Melon Crops

Presentation (PDF, 282KB)

Authors: Matheron, M.

Location Presented: Horticulture Integrated Pest Management Seminar, Pinal County Cooperative Extension Office, Casa Grande, AZ.
Dec 2002

Soilborne Diseases of Melon and Watermelon

Presentation (PDF, 82KB)

Authors: Olsen, M.

Location Presented: Annual Desert Crop Workshop, Yuma, AZ.

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