Peach diseases management

Recommended

Description

Prunus persica

DISEASES OF PEACH

 

1 Leaf curl : Taphrina deformans

LEAF CURL

Taphrina deformans

1. Leaf curl

C.O. : Taphrina deformans

Class : Taphrinomycetes

Order : Taphrinales

Family : Taphrinaceae

Symptoms:

 

» Diseased leaves can usually be identified soon after

they emerge from the bud, due to their red color and

twisted shape.

 

» As the leaves develop, they become increasingly

distorted and ultimately thick and rubbery compared

to normal leaves. The colors of the leaves change from

the normal green to red and purple.

 

» Fruit may fail to develop from diseased blossoms, or

 

may be affected, showing a reddish color.

Favourable condition:

 

v’ Temperature : Below 19°C.

v Cool and wet winter

 

Disease cycle:

 

* PSI: Infected leaves, bark, buds,twigs. Ascospores

 

« SSI: Rain and wind Conidia

 

* This pathogen is called monocyclic, meaning these

fungal spores infect peach leaves only once a year in

the spring.

 

Disease Cycle

 

Intercellular Ascospores

mycelium and inascus

subcuticular

 

Conidium ascogenous cells

 

penetrates

 

host tissue 5 SN —

 

3 Healthy and

infected

peach leaf

 

Developing asa

breaking through

cuticle

 

New infection

7° Conidium Layer of asa

germinating onirfected

 

leaf and fruit

 

f Owerwintering & Conidium

 

@ Healthy

i fruit

A Conidia

overwintering

\ on buds or

twigs Plum pocket

 

O

 

Buddin Ir Qspore

 

Management:

 

» The most effective method is to plant peach trees

possibly covered by a mat during the winter, to keep

winter rain away from the buds before they burst

(incidentally to delay blossoming until spring frosts

are over).

 

» Copper based mixtures (such as bordeaux mixture)

and lime sulphur are two fungicides commonly used.

» Peach cultivars can be planted which show some

resistance to peach leaf curl, or at least regenerate

 

rapidly, such as Peach ‘Benedicte’.