February 2024 - 16

PLANT HEALTH
DOWNY MILDEW
If you are growing susceptible crops such as
basil, impatiens, coleus and roses you should also
scout frequently for downy mildew. Recognizing
early signs will help preserve plant quality and
health. Leaf discoloration or mottling, often within
the veins, is the most common initial symptom.
Under humid conditions the pathogen will
sporulate, creating a fuzzy or downy growth on
the underside of the leaf, corresponding with the
interveinal discoloration. When the fungus invades
the plant internally, stunting, distortion and
mortality can occur.
To reduce the threat of downy mildew, take
similar steps as with Botrytis. Avoid conditions
conducive to disease development by reducing
humidity and scouting frequently to identify early
signs of disease and remove diseased plants.
A fungicide targeting oomycete pathogens will
be necessary to prevent and keep this disease
controlled.
PYTHIUM
Protecting plants from root and stem rots
caused by Pythium spp. can be a challenge,
particularly during the winter and early spring,
when the weather may be cloudier and greenhouse
temperatures are cooler. Under these conditions,
the growing media tends to stay wet longer,
allowing oospores of Pythium spp. to germinate
and invade wounds and tender plant tissue.
While unrooted cuttings and young seedlings in
propagation areas are at risk because of frequent
misting and high humidity, established plants are
also at risk for losing healthy roots under these
conditions.
When monitoring crops for signs of infection be
sure to look for stunted plants, plants with light
Downy mildew
on basil.
Pythium root rot.
16
FEBRUARY 2024 GPNMAG.COM

http://www.GPNMAG.COM

February 2024

Table of Contents for the Digital Edition of February 2024

Editor's Report | Hot and cold
Table of Contents
Forty Under 40 Perspectives | Keeping fields cleaner
Dr. Bugs | Stratiolaelaps scimitus
Technically Speaking | LED lighting: A 2024 update
Plant Health | Healthy crops
Production | Understanding poinsettia heat delay
2024 California Spring Trials | CASTing into spring
Lighting | What's your lighting strategy
Pest Control | It's all about the buzz
Culture Report | DoubleShot series
Product Marketplace
Industry News/Events
Classifieds/Ad Index
February 2024 - Editor's Report | Hot and cold
February 2024 - 2
February 2024 - Table of Contents
February 2024 - 4
February 2024 - 5
February 2024 - Forty Under 40 Perspectives | Keeping fields cleaner
February 2024 - 7
February 2024 - Dr. Bugs | Stratiolaelaps scimitus
February 2024 - 9
February 2024 - 10
February 2024 - 11
February 2024 - Technically Speaking | LED lighting: A 2024 update
February 2024 - 13
February 2024 - Plant Health | Healthy crops
February 2024 - 15
February 2024 - 16
February 2024 - 17
February 2024 - Production | Understanding poinsettia heat delay
February 2024 - 19
February 2024 - 20
February 2024 - 21
February 2024 - 2024 California Spring Trials | CASTing into spring
February 2024 - 23
February 2024 - 24
February 2024 - 25
February 2024 - 26
February 2024 - 27
February 2024 - 28
February 2024 - 29
February 2024 - 30
February 2024 - 31
February 2024 - 32
February 2024 - 33
February 2024 - 34
February 2024 - 35
February 2024 - Lighting | What's your lighting strategy
February 2024 - 37
February 2024 - Pest Control | It's all about the buzz
February 2024 - 39
February 2024 - Culture Report | DoubleShot series
February 2024 - 41
February 2024 - 42
February 2024 - 43
February 2024 - Product Marketplace
February 2024 - 45
February 2024 - 46
February 2024 - 47
February 2024 - Industry News/Events
February 2024 - 49
February 2024 - Classifieds/Ad Index
February 2024 - 51
February 2024 - 52
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https://www.nxtbook.com/greatamericanmediaservices/GPN/march-2024
https://www.nxtbook.com/greatamericanmediaservices/GPN/february-2024
https://www.nxtbook.com/greatamericanmediaservices/GPN/january-2024
https://www.nxtbook.com/greatamericanmediaservices/GPN/2024-guide-to-cannabis-production
https://www.nxtbook.com/greatamericanmediaservices/GPN/november-december-2023
https://www.nxtbook.com/greatamericanmediaservices/GPN/october-2023
https://www.nxtbook.com/greatamericanmediaservices/GPN/new-varieties-digital-guide-2024
https://www.nxtbook.com/greatamericanmediaservices/GPN/september-2023
https://www.nxtbook.com/greatamericanmediaservices/GPN/august-2023
https://www.nxtbook.com/greatamericanmediaservices/GPN/july-2023
https://www.nxtbook.com/greatamericanmediaservices/GPN/big-grower-july-2023
https://www.nxtbook.com/greatamericanmediaservices/GPN/june-2023
https://www.nxtbook.com/greatamericanmediaservices/GPN/may-2023
https://www.nxtbook.com/greatamericanmediaservices/GPN/april-2023
https://www.nxtbook.com/greatamericanmediaservices/GPN/big-grower-april-2023
https://www.nxtbook.com/greatamericanmediaservices/GPN/2023-guide-to-hemp-production
https://www.nxtbook.com/greatamericanmediaservices/GPN/march-2023
https://www.nxtbook.com/greatamericanmediaservices/GPN/february-2023
https://www.nxtbook.com/greatamericanmediaservices/GPN/big-grower-january-2023
https://www.nxtbook.com/greatamericanmediaservices/GPN/january-2023
https://www.nxtbook.com/greatamericanmediaservices/GPN/2023-guide-to-cannabis-production
https://www.nxtbook.com/greatamericanmediaservices/GPN/november-december-2022
https://www.nxtbook.com/greatamericanmediaservices/GPN/big-grower-october-2022
https://www.nxtbook.com/greatamericanmediaservices/GPN/october-2022
https://www.nxtbook.com/greatamericanmediaservices/GPN/gpn-new-varieties-digital-guide-2023
https://www.nxtbook.com/greatamericanmediaservices/GPN/september-2022
https://www.nxtbook.com/greatamericanmediaservices/GPN/august-2022
https://www.nxtbook.com/greatamericanmediaservices/GPN/big-grower-july-2022
https://www.nxtbook.com/greatamericanmediaservices/GPN/july-2022
https://www.nxtbook.com/greatamericanmediaservices/GPN/june-2022
https://www.nxtbook.com/greatamericanmediaservices/GPN/may-2022
https://www.nxtbook.com/greatamericanmediaservices/GPN/big-grower-april-2022
https://www.nxtbook.com/greatamericanmediaservices/GPN/april-2022
https://www.nxtbook.com/greatamericanmediaservices/GPN/march-2022
https://www.nxtbook.com/greatamericanmediaservices/GPN/february-2022
https://www.nxtbook.com/greatamericanmediaservices/GPN/cannabisguide-2022
https://www.nxtbook.com/greatamericanmediaservices/GPN/hempguide-2022
https://www.nxtbook.com/greatamericanmediaservices/GPN/newvarieties-2022
https://www.nxtbook.com/greatamericanmediaservices/GPN/big-grower-january-2022
https://www.nxtbook.com/greatamericanmediaservices/GPN/january-2022
https://www.nxtbook.com/greatamericanmediaservices/GPN/december-2021
https://www.nxtbook.com/greatamericanmediaservices/GPN/big-grower-november-2021
https://www.nxtbook.com/greatamericanmediaservices/GPN/november-2021
https://www.nxtbook.com/greatamericanmediaservices/GPN/october-2021
https://www.nxtbook.com/greatamericanmediaservices/GPN/big-grower-september-2021
https://www.nxtbook.com/greatamericanmediaservices/GPN/september-2021
https://www.nxtbook.com/greatamericanmediaservices/GPN/august-2021
https://www.nxtbook.com/greatamericanmediaservices/GPN/big-grower-july-2021
https://www.nxtbook.com/greatamericanmediaservices/GPN/july-2021
https://www.nxtbook.com/greatamericanmediaservices/GPN/june-2021
https://www.nxtbook.com/greatamericanmediaservices/GPN/may-2021
https://www.nxtbook.com/greatamericanmediaservices/GPN/april-2021
https://www.nxtbook.com/greatamericanmediaservices/GPN/big-grower-march-2021
https://www.nxtbook.com/greatamericanmediaservices/GPN/march-2021
https://www.nxtbook.com/greatamericanmediaservices/GPN/february-2021
https://www.nxtbook.com/greatamericanmediaservices/GPN/cannabisguide-2021
https://www.nxtbook.com/greatamericanmediaservices/GPN/hempguide-2021
https://www.nxtbook.com/greatamericanmediaservices/GPN/newvarieties-2021
https://www.nxtbook.com/greatamericanmediaservices/GPN/big-grower-january-2021
https://www.nxtbook.com/greatamericanmediaservices/GPN/january-2021
https://www.nxtbook.com/greatamericanmediaservices/GPN/december-2020
https://www.nxtbook.com/greatamericanmediaservices/GPN/big-grower-november-2020
https://www.nxtbook.com/greatamericanmediaservices/GPN/november-2020
https://www.nxtbook.com/greatamericanmediaservices/GPN/october-2020
https://www.nxtbook.com/greatamericanmediaservices/GPN/big-grower-september-2020
https://www.nxtbook.com/greatamericanmediaservices/GPN/september-2020
https://www.nxtbook.com/greatamericanmediaservices/GPN/august-2020
https://www.nxtbook.com/greatamericanmediaservices/GPN/big-grower-july-2020
https://www.nxtbook.com/greatamericanmediaservices/GPN/july-2020
https://www.nxtbook.com/greatamericanmediaservices/GPN/june-2020
https://www.nxtbook.com/greatamericanmediaservices/GPN/may-2020
https://www.nxtbook.com/greatamericanmediaservices/GPN/april-2020
https://www.nxtbook.com/greatamericanmediaservices/GPN/californiaspringtrials-2020
https://www.nxtbook.com/greatamericanmediaservices/GPN/big-grower-march-2020
https://www.nxtbook.com/greatamericanmediaservices/GPN/march-2020
https://www.nxtbook.com/greatamericanmediaservices/GPN/february-2020
https://www.nxtbook.com/greatamericanmediaservices/GPN/cannabisguide-2020
https://www.nxtbook.com/greatamericanmediaservices/GPN/hempguide-2020
https://www.nxtbook.com/greatamericanmediaservices/GPN/big-grower-january-2020
https://www.nxtbook.com/greatamericanmediaservices/GPN/january-2020
https://www.nxtbook.com/greatamericanmediaservices/GPN/december-2019
https://www.nxtbook.com/greatamericanmediaservices/GPN/big-grower-november-2019
https://www.nxtbook.com/greatamericanmediaservices/GPN/november-2019
https://www.nxtbook.com/greatamericanmediaservices/GPN/october-2019
https://www.nxtbook.com/greatamericanmediaservices/GPN/big-grower-september-2019
https://www.nxtbook.com/greatamericanmediaservices/GPN/september-2019
https://www.nxtbook.com/greatamericanmediaservices/GPN/august-2019
https://www.nxtbook.com/greatamericanmediaservices/GPN/big-grower-july-2019
https://www.nxtbook.com/greatamericanmediaservices/GPN/july-2019
https://www.nxtbook.com/greatamericanmediaservices/GPN/june-2019
https://www.nxtbook.com/greatamericanmediaservices/GPN/may-2019
https://www.nxtbook.com/greatamericanmediaservices/GPN/april-2019
https://www.nxtbook.com/greatamericanmediaservices/GPN/californiaspringtrials-2019
https://www.nxtbook.com/greatamericanmediaservices/GPN/big-grower-march-2019
https://www.nxtbook.com/greatamericanmediaservices/GPN/march-2019
https://www.nxtbook.com/greatamericanmediaservices/GPN/february-2019
https://www.nxtbook.com/greatamericanmediaservices/GPN/undercontrol-2019
https://www.nxtbook.com/greatamericanmediaservices/GPN/big-grower-january-2019
https://www.nxtbook.com/greatamericanmediaservices/GPN/january-2019
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