Pepper disease control Parm Randhawa,, Ph.D. California Seed & Plant Lab
Agenda Symptom recognition Where the disease come from Disease Management Check list
Disease control in greenhouse Depends on Growing in soil Containers (with potting mix) Hydroponic (Rockwool etc)
Fusarium stem rot
Fusarium - Infection at nodes
Red perithecia (Sexual spores can discharge to 6 ft at night
Fusarium How is pathogen introduced Soil (people, tools) Previous crop (debris etc) Airborne ascospores
Fusarium - Control Avoid salt burn (if rockwool dries) Reduce humidity (slow temp increase at night) Bio-control
Fusarium like symptoms Water soaking Erwinia stem canker
Erwinia carotovora How pathogen get introduced Irrigation with untreated water (ponds, rivers) Handling from people (hands)
Erwinia - Control Treat water (1 ppm Chlorine kills in 30 seconds) Workers (wash hands)
Xanthomonas
Xanthomonas control Buy tested seed Resistant varieties (multiple races) Actiguard (induces resistance) Copper / Maneb sprays Bacterio-phage application can help
Anthracnose (fruit rot)
Anthracnose control Seed treatment Debris removal
Damping off - nursery problem
Damping off - control Disease free media (steamed) Sanitation (trays etc) Raised benches Do not over water Treated water 2-Fungicide drench can help (Ridomil + Topsin M)
Sudden Wilt Phytophthora capsici
Phytophthora: All parts nfected
Phytophthora Where it comes from Seed borne? Wind blown rains bring spores from other plants (tomato, cucurbits, weeds) Irrigation water (rivers) Soil movement (oospores survive) Fungus gnats Disease develops in 3-4 days after infection
Phytophthora Management Treat water Disinfection of nursery containers Fungicides Good drainage (drainage area Keep weed free) Lab ID should be done to select correct fungicide
Control with Revus + Rodomil
Black sclerotia inside stem White mold on stem Sclerotinia white mold Germinating sclerotia
Sclertotinia control Cool moist weather disease Air circulation Sanitation Topsin M
Southern blight - management Hot weather disease Sanitation Aeration Spot application of fungicides (Quadris etc)
Other fungal / bacterial diseases Bacteria Ralstonia, Pseudomonas syringae Fungi Pow mildew, Verticillium, Cercospora, Stemphyllum, Downy mildew, gray leaf spot I have assumed that these are less frequent in greenhouse pepper culture
Viruses Cause malformation but do not kill Many viruses same symptom One virus many symptoms Symptoms provide a clue but Lab test is needed for Identification
How viruses get introduced Aphids Thrips White fly Leaf hopper Seed Cucumber mosaic, Potato virus Y, Tobacco Etch, Alfalfa mosaic, Pepper mottle Tomato spotted wilt Chino del tomate, Pepper mild tigre, Pepper hausteco, Sinaloa leaf curl Beet curly top Tobacco mosaic, tomato mosaic, pepper mild mottle
15-Virus PCR test Test DNA Viruses Gemini group (CdTV, PHV, SLCV, TPV, SGMV), BCTV RNA TSWV, TMV, ToMV, CMV, PMMV, TEV, PVY, AMV, PMV
Aphid transmitted viruses
CMV
Chilli Veinal mottle
Tobacco etch
Potato virus Y
Alalfa mosaic virus Bleaching of leaves
Thrips transmitted viruses
Tomato spotted wilt
White fly transmitted
Gemini viruses (DNA viruses)
Chino del tomate virus (CdDT)
Serrano Golden Mosaic
Texas pepper virus
Leaf hopper transmitted
Beet curly top
Seed transmitted viruses
Tobacco mosaic
Tomato mosaic
Pepper mild mottle virus
Virus control Screens for insect control Hand wash for tobamo viruses Tested seed (for tobamo viruses) No smoking (for TMV) Weed removal Stylet oil sprays for aphid borne Insecticides
Color spots (varietal) Cracking (water imbalance) Blossom end rot (calcium) Physiology disorders
Disease management
Virulent Pathogen Susceptible Host Favorable Environment Disease
Pathogen elimination Weed removal Insect screens Plastic cover on soil Irrigation water treatment Foot bath Etc
Double door for insect control Serves as air-lock
Clean cement walkway will keep Crawling insects away (ants)
Boot scrubber to reduce soil going into greenhouse
Foot bath to sterilize boots Greenshield, Physan20
Hand wash station (near entry) (Disease control during pruning, tying, harvesting etc)
Weed cloth 10 feet around greenhouse
Reflective mulch around greenhouse (to confuse insects)
Check for any holes in the screen
Debris removal at end of crop Before After
Plastic mulch on ground will keep soil pathogen away
Another Plastic Surface
Cull Pile Away from greenhouse Make hole Cover with soil later on
Special care of nursery 1 foot off ground
Crop Free Period Solarization (130F)
Elimination of susceptible host Resistant varieties are available TMV, PMMV, Xanth, Phytophthora
Creating unfavorable environment Heaters for step heating at night Fans to reduce free moisture Fertilizer program for inducing resistance Scouting and treatment to reduce insect /disease pressure Biologicals to slow down disease
Discontinuous system is good
Aeration and thus disease control is same in this V trellis
Keeping pedicel controls postharvest Erwinia soft rot
Biologicals keep working against pests Root fungi GSB, PM, DM Rootshield, Pre-stop, Mycostop Rhapsody, Serenade, Sonata
Gliocladium (Pre-stop) is parasitic on Rhizoctonia
Trichoderma for disease control (harzianum, viride, hamatum species)
Scouting for insects / diseases
Lab selection Choose a lab that gives quick diagnosis
You can send sample to me Packing Pack good Include shipping documents (permit) Use Red /white shipping label (from me) Ship Ready to ship
Making action plan Assessment of risk Check list
Risk inventory Weeds Other crops Proximity of cull pile History of previous crop Weed risk
End of Season: Check List Trash hole is ready Irrigation lines flushed and disinfected Nursery is treated for fungus gnats Foot bath ready Tools, carts etc disinfected Weeds, debris removed Scouting supplies are ready Met with staff and reviewed
Thank you