February 2025 - 30

PLANT HEALTH
Poinsettia
PROTECTION
Pythium in
production is
managed with
comprehensive
prevention
BY JANNA BECKERMAN
P
oinsettia production faces significant challenges,
from the intense summer heat to the cool or
freezing conditions of winter. These extremes
make it a prime environment for pythium, a pathogen
often referred to as the " common cold " of the plant
kingdom (Figure 1). Pythium primarily attacks plant roots
but can also cause cutting rots, stem rots and foliar blight
when conditions are favorable (Figures 2a,b).
SYMPTOMS
Early indicators of pythium root rot include wilting,
stunting and symptoms of nutrient deficiency. As the
infection progresses, root tips become discolored and
entire roots appear watersoaked (Figure 2a). At this
stage, the root cortex may slough off, leaving a strand of
vascular tissue. These lesions eventually turn into a soft,
watery rot, and the infected plant may wilt and die rapidly.
Infected plants that survive transplanting often remain
stunted and fail to produce healthy root systems.
Conditions that favor pythium also encourage other root
rots, like rhizoctonia, which requires different fungicides
for control. Therefore, while pythium may be the primary
suspect, a conclusive diagnosis is necessary to manage
root rot effectively.
30 FEBRUARY 2025 GPNMAG.COM
Figure 1.
Pythium is often
referred to as
the " common
cold " of the
plant kingdom.
Photos by Janna
Beckerman.

http://www.GPNMAG.COM

February 2025

Table of Contents for the Digital Edition of February 2025

Table of Contents
Editor's Report
2025 California Spring Trials | Turn over a new leaf
CEA | Regulating crops in a controlled space
Grower Profile | North Carolina Farms
Variety Information | Poinsettia Variety Day 2024
Plant Health | Poinsettia protection
Technology | Taking control
Dr. Bugs | Life cycles of insect and mite pests
Technically Speaking | Getting the most out of energy and shade curtains
Culture Report | Heliopsis 'Burning Hearts'
Forty Under 40 Perspectives | A day in the life of plant protection
Product Marketplace
Classifieds/Ad Index
February 2025 - 1
February 2025 - 2
February 2025 - Table of Contents
February 2025 - Editor's Report
February 2025 - 5
February 2025 - 6
February 2025 - 7
February 2025 - 2025 California Spring Trials | Turn over a new leaf
February 2025 - 9
February 2025 - 10
February 2025 - 11
February 2025 - CEA | Regulating crops in a controlled space
February 2025 - 13
February 2025 - 14
February 2025 - 15
February 2025 - Grower Profile | North Carolina Farms
February 2025 - 17
February 2025 - 18
February 2025 - 19
February 2025 - 20
February 2025 - 21
February 2025 - 22
February 2025 - 23
February 2025 - Variety Information | Poinsettia Variety Day 2024
February 2025 - 25
February 2025 - 26
February 2025 - 27
February 2025 - 28
February 2025 - 29
February 2025 - Plant Health | Poinsettia protection
February 2025 - 31
February 2025 - 32
February 2025 - 33
February 2025 - Technology | Taking control
February 2025 - 35
February 2025 - 36
February 2025 - 37
February 2025 - Dr. Bugs | Life cycles of insect and mite pests
February 2025 - 39
February 2025 - Technically Speaking | Getting the most out of energy and shade curtains
February 2025 - 41
February 2025 - Culture Report | Heliopsis 'Burning Hearts'
February 2025 - 43
February 2025 - Forty Under 40 Perspectives | A day in the life of plant protection
February 2025 - 45
February 2025 - Product Marketplace
February 2025 - 47
February 2025 - 48
February 2025 - 49
February 2025 - Classifieds/Ad Index
February 2025 - 51
February 2025 - 52
https://www.nxtbook.com/greatamericanmediaservices/GPN/february-2025
https://www.nxtbook.com/greatamericanmediaservices/GPN/january-2025
https://www.nxtbook.com/greatamericanmediaservices/GPN/november-december-2024
https://www.nxtbook.com/greatamericanmediaservices/GPN/october-2024
https://www.nxtbook.com/greatamericanmediaservices/GPN/new-varieties-digital-guide-2025
https://www.nxtbook.com/greatamericanmediaservices/GPN/september-2024
https://www.nxtbook.com/greatamericanmediaservices/GPN/august-2024
https://www.nxtbook.com/greatamericanmediaservices/GPN/july-2024
https://www.nxtbook.com/greatamericanmediaservices/GPN/june-2024
https://www.nxtbook.com/greatamericanmediaservices/GPN/may-2024
https://www.nxtbook.com/greatamericanmediaservices/GPN/april-2024
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
https://www.nxtbookmedia.com