Fusarium wilt in Phoenix - PDF Free Download

Fusarium wilt in Phoenix Michael Matheron Yuma Agricultural Center matheron@ag.arizona.edu

What causes Fusarium wilt of Phoenix species?

What causes Fusarium wilt of Phoenix species? Fusarium oxysporum

Fusarium oxysporum Mycelium Macrospores Microspores Chlamydospores & macrospores

Characteristics of Fusarium oxysporum Some members of this species only live on dead plant tissue (not plant pathogens) Others are plant pathogens Those that are pathogenic can also can live on dead plant tissue when living host plant tissue is not available Enables the pathogen to remain in soil indefinitely

Characteristics of Fusarium oxysporum Those that are plant pathogens cause disease on specific plant hosts known as forma speciales or special forms There are over 100 known special forms of Fusarium oxysporum, each with a specific type or group of plants on which they can cause disease

Examples of Fusarium oxysporum special forms Fusarium oxysporum f. sp. albedinis Fusarium oxysporum f. sp. canariensis Fusarium oxysporum f. sp. cannabis Fusarium oxysporum f. sp. citri Fusarium oxysporum f. sp. cubense Fusarium oxysporum f. sp. lactucae Fusarium oxysporum f. sp. lycopersici Fusarium oxysporum f. sp. melonis Fusarium oxysporum f. sp. palmarum

Fusarium wilt development Fusarium oxysporum invades plants through roots Can also be transmitted from diseased to healthy plants by pruning tools Grows in plant xylem, which transports water and nutrients from roots to foliage Xylem becomes obstructed and plant wilts and dies

Fusarium wilt of queen palm and Mexican fan palm Caused by Fusarium oxysporum f. sp. palmarum Hosts are queen palm (Syagrus romanzoffiana) and Mexican fan palm (Washingtonia robusta) As of 2013, this disease only known to occur in Florida (widespread) and Houston-Galveston area of Texas Symptoms normally begin on oldest (lowest) leaves, progressing to younger leaves, eventually killing the plant

Fusarium wilt of queen palm: Symptoms One-sided chlorosis and necrosis of leaves Red brown to dark brown stripe on petiole and rachis

Fusarium wilt of palm: Symptoms Internal discoloration of leaf petiole/rachis due to infection by Fusarium oxysporum

Fusarium wilt of queen palm: Symptoms Late stage symptoms of Fusarium wilt

Fusarium wilt of Mexican fan palm: Symptoms One-sided chlorosis and necrosis with reddish brown stripe on petiole

Fusarium wilt of Mexican fan palm: Symptoms Fusarium wilt develops first on lower leaves, then progresses upward to eventually kill terminal bud

Fusarium wilt of Canary Island date palm Caused by Fusarium oxysporum f. sp. canariensis (Foc) Develops on Canary Island date palm (Phoenix canariensus) First documented in the U.S. in California (1970s), subsequently found in Florida, Louisiana, Nevada, Texas, South Carolina Experimental and observational evidence suggests that other Phoenix species (date palm, Senegal date palm, wild date palm) could be susceptible to Foc, but occurrences are extremely rare

Fusarium wilt of Canary Island date palm Symptoms One-sided chlorosis and necrosis of leaves

Fusarium wilt of Canary Island date palm Symptoms Reddish brown stripe on petiole Internal discoloration of petiole

Fusarium wilt of Canary Island date palm Symptoms Multiple palms dying due to Fusarium wilt. Pathogen can be moved by infested pruning tools.

Fusarium wilt of date palm (Bayoud) Caused by Fusarium oxysporum f. sp. albedinis Develops on date palm (Phoenix dactylifera) Commonly known as bayoud disease Comes from the Arabic word abiadh, which means white, refers to whitening of fronds of diseased palms First reported in 1870 in Zagora-Morocco Has killed at least 12,000,000 palms in Morocco and 3,000,000 in Algeria Medjool, Deglet Nour, BouFegouss particularly susceptible, according to Zaid, et al

Fusarium wilt of date palm: Symptoms Progression of whitening and dying process on one side of leaf

Fusarium wilt of date palm: Symptoms Terminal stage of Fusarium wilt of date palm casued by Fusarium oxysporum f. sp. albedinis

Managing Fusarium wilt of date palm

Managing Fusarium wilt of date palm AVOID THE DISEASE!!

Managing Fusarium wilt of date palm PREVENT INTRODUCTION OF THE PATHOGEN Do not introduce contaminated plant material or soil into healthy date plantings

Managing Fusarium wilt of date palm PREVENT INTRODUCTION OF THE PATHOGEN Do not introduce contaminated plant material or soil into healthy date plantings If Fusarium wilt should ever be detected Immediately initiate isolation and eradication procedures Uproot and incinerate infected trees followed by soil fumigation and other eradication procedures

Managing Fusarium wilt of date palm PREVENT INTRODUCTION OF THE PATHOGEN Do not introduce contaminated plant material or soil into healthy date plantings If Fusarium wilt should be detected, Immediately initiate isolation and eradication procedures Uproot and incinerate infected trees followed by soil fumigation and other eradication procedures Development and deployment of resistant high quality varieties

Other management considerations: Sanitation Prevent movement of pathogen Anything that moves infested soil or plant material can spread the pathogen Pruning and harvesting operations, workers shoes, tractors and other farm equipment

Other management considerations: Crop rotation Pathogenic F. oxysporum can colonize other plant types without causing disease For example, Fol can colonize living tomato, cantaloupe, watermelon, cotton, broccoli, cauliflower, and spinach plants without causing disease symptoms can grow on dead organic matter such a crop waste The magnitude of the effect of nonhost plants and organic matter on pathogen population longevity in soil is unknown