The Gall Of Plant Diseases [Cecidium]

Contents

The gall of plant diseases [Cecidium]

A gall or cecidium is usually defined as an abnormal plant over growth caused by the parasitic plant or animal.

▲ Phytocecidium: Caused by parasitic plant.

▲ Zoocecidium: Caused by animal. Gall forming mites and insect Mites Acarus, Eriophyes, Phyllocoptes. Insect

▲ Hymenoptera: Cynipidae (Gall wasps).

▲ Diptera: Agromyzidae (greenflies, blackflies or whiteflies), Tephritoidea (gall flies), Cecidomyiidae (gall midges), Chloropidae (grass flies).

▲ Homoptera: Aphididae (Chinese sumac aphid), Coccoidea (Scale insect), Psyllidae (Jumping plant lice).

▲ Besides, a few member of the Coleoptera and Lepidoptera can also produce gall. How insect produce gall

Gall insect → Immature stage → Stimulating substance → Stimulated host tissue → Over growth → Gall.

Example: Rice gall midge and Onion shoot of rice.

A. Insect

Common name Scientific name Gall producing site

Rice gall midge Orseolia oryzae Stem

Mango leaf gall midge Procontarinia matteiana Leaf

Mango twig gall midge Rhabdophaga mangifera Twig

Mango bud gall psyllid Apsylla cistellata Bud

Golden rod Gall Midge Eurosta spp. Stem

Wooly Oak gall wasps Callirhytis lanata Leaf

Mossy Rose Gall Wasp Diplolepis rosae Leaf

Eastern spruce gall adelgid Adelges abietis Twig

B. Mites

1. Litchi mite ……………………. Aceria litchii ……………………….. Leaf.

2. Pear blister mite …………….. Eriophyes pyri …………………….. Leaf.