Downy Mildew Found In California Basil Plants

Basil plants that originated from a nursery on the central coast of California nursery were recently found infected with the downy mildew pathogen, Peronospora belbahri, in a home and garden store in the state.

This is a new pathogen that can cause serious damage to both culinary and ornamental basil plants, says Surendra Dara, strawberry and vegetable crops advisor for University of California (UC) Cooperative Extension in Santa Barbara and San Luis Obispo counties. Symptoms include yellowing of the area between the veins on the upper leaf surface and growth of fungal mycelia and purplish grey spores on the lower surface. Yellowing on the upper leaf surface can be confused with nutritional deficiency, so careful examination of the lower side is important.

Basil downy mildew was first reported in the United States in 2007 in Florida and in several eastern states by 2008, Dara says. It was also found in California by 2009. Infected seeds and plants are the main sources of infection. Growers should try to obtain clean seeds, he advises.

Spores can be dispersed by wind and overhead irrigation can also aid in the dispersal of the inoculum. Regular monitoring of fields for early detection of the infection and timely application of fungicides is important for managing this disease. Proper ventilation and temperature control in the greenhouses is also critical, as prolonged leaf wetness, high humidity and cool weather promote the disease development.

Leave a Reply

One comment on “Downy Mildew Found In California Basil Plants

Latest Stories
National Garden Bureau California Vegetable Summer Trials

May 26, 2016

California Summer Vegetable Trials In August Will Cover…

The National Garden Bureau is once again organizing summer vegetables trials this August in California, giving attendees the opportunity to visit with several breeding companies.

Read More
IGC App For 2016 Shows

May 26, 2016

IGC Shows Release Free Apps To Help You Plan For Both T…

Free event planning apps for each show are now available for download in the Apple App Store and on Google Play.

Read More
SBI Rack Scanning feature

May 26, 2016

Take Your Data Management To The Next Level

New developments in software technology allow growers to customize inventory, tracking, and labor performance into systems unique to their greenhouse operations.

Read More
Eason 2017 Perennials Guide

May 25, 2016

Eason Horticultural Resources Releases New Perennials G…

The two guides are available in digital and print versions and offer information from several breeders.

Read More
Echinacea ‘Butterfly Rainbow Marcella’

May 25, 2016

15 New Perennials For Bees, Butterflies, And Other Poll…

These 15 new perennials, available for retail in 2016 and 2017, will produce colorful flowers and foliage year after year, providing habitat and food for bees, butterflies, birds, moths, and other pollinators.

Read More
P.Allen Smith Cut Flowers

May 25, 2016

Sakata Seed America And P. Allen Smith Extend Partnersh…

Sakata is taking its partnership with plantsman P. Allen Smith a step further to create the P. Allen Smith Home Grown Cut Flowers Collection, a selection of premium cut flower seed hand-picked by Smith and bred exclusively by Sakata.

Read More
Triathlon BA container shot

May 24, 2016

OHP’s Triathlon Biofungicide Now Listed By The Organic …

Triathlon BA is a broad-spectrum preventative biofungicide that provides control of many foliar and soilborne diseases in ornamentals and herbs.

Read More
Costa Farms won International Grower of the Year. Representing the operation, (left to right) were Chuck Zala, Michael Vera, Menachem Ganon, Jose Costa, and Mike Rimland

May 24, 2016

AIPH Seeking Entries For Its International Grower of th…

The International Association of Horticultural Producers (AIPH) is inviting ornamental growers from all around the world to enter the AIPH International Grower of the Year Awards (IGOTY) for 2017. Last year’s big winner was Florida-based Costa Farms.

Read More
Coleus Fancy Feathers Pink (Terra Nova Nurseries)

May 23, 2016

Take A Sneak Peek at Terra Nova Nurseries’ New Coleus F…

A brand-new collection of Terra Nova Nurseries coleus varieties called the Fancy Feathers Series is now available to growers for online orders. The series produces narrow, feather-like leaves and offers a mounded habit.

Read More
Gotham Greens Atrium Style Greenhouse Chicago

May 23, 2016

What’s Good For The Environment Is Good For Business [O…

Investing in technology to become more sustainable “always goes hand in hand,” says Abe VanWingerden, co-CEO of Metrolina Greenhouses. “If it is good for the environment, it normally is good for business over the long term.” That connection was abundantly clear in the responses we received to this year’s Top 100 Growers Survey. VanWingerden points to three investments Metrolina has made as good examples of how technology can reduce an operation’s carbon footprint and pay dividends financially. Its biomass system burns locally sourced waste wood — a renewable resource; its ozone water treatment system cleans irrigation water, reducing the need for fertilizers and pesticides, and improving plant quality and precision growing; and electrostatic sprayers reduce water and chemical use, and provide more targeted chemical applications. Other Top 100 Growers have found VanWingerden’s theory to be true, as well. Costa Farms’ investment in solar energy panels on three buildings at its […]

Read More

May 23, 2016

Ian Baldwin Sees Several Garden Trends Developing This …

The garden industry consultant reads the mid-spring tea leaves and sees several trends emerging.

Read More

May 23, 2016

Manhattan’s Urban Garden Center Suffers Second Di…

Two years after a nearby gas explosion destroyed the store in Manhattan's Spanish Harlem, Urban Garden Center had a four-alarm fire that disrupted a popular train route, and the garden retailer is now dealing with an angry community.

Read More
Aerial_view_of_the_Bayer_cross_high_res

May 23, 2016

Bayer Sells Consumer Garden Products Division To French…

The sale to SBM Développement comes just as Bayer AG makes a bid for Monsanto.

Read More
GG Tech Editorial Advisors Feature Image

May 23, 2016

Meet The New Editorial Advisors For Greenhouse Growe…

Greenhouse Grower TECHNOLOGY presents the inaugural members of its Editorial Advisory Board, six pillars of knowledge about greenhouse automation and technology. Get to know each of these gentlemen and what they’ll help bring to each issue.

Read More
Pythium On Chrysanthemum

May 20, 2016

How To Prevent Pythium In Fall Garden Mums

Avoid profit loss in fall garden mums due to pythium root rot with good drainage and integrated pest management practices that reduce risk factors.

Read More
Agro-K

May 19, 2016

Agro-K Expands Distribution In New England Through Part…

Agro-K, which manufactures conventional and organic foliar plant nutrients, will distribute its full line of foliar fertilizers and soil biological products through NEAG.

Read More
Stained poinsettia foliage from high iron

May 19, 2016

Minimize Build-up In Your Water Pipes

This article is the third in a series of case studies designed to help growers reduce, remediate, and recycle irrigation water as part of a multi-state research grant (CleanWateR3.org).

Read More

May 17, 2016

Your Best Greenhouse Is Your Best Bet For Growing Veget…

It doesn’t matter if it’s a retrofitted greenhouse or brand new freestanding high tunnel, the type of structure you use for your vegetable growing makes all the difference in the quality of the crop you grow.

Read More
[gravityform id="35" title="false" description="false"]