Practical 6: Higher Fungi - Taxonomy and Pathological Importance (Phylum Basidiomycota)

December 20, 2019

Practical 6: Higher Fungi - Taxonomy and Pathological Importance (Phylum Basidiomycota)

OBJECTIVES

To observe the disease symptoms caused by fungi in Phylum Basidiomycota.
To observe the stage of basidiospore in Puccinia graminis.

INTRODUCTION

The Phylum Basidiomycota is considered as the most developed group of fungi. The example such as mushrooms, toadstools, puffballs and stinkhorns. The rust and the smut fungi are included although considered lower within the group. Some of the fungi considered as plant pathogen that cause millions of losses to crops annually. On the positive side, species of mushrooms are edible and contributes to the food industry. The Basidiomycota generally produce sexual spores that called as basidiospores that usually 4 in number on a structure called the basidium.

Activity.

Plant disease specimens.

Causal agent : Puccinia polysora

Ground nut rust Causal agent : Puccina arachidis Symptoms : Orange colour of uredinia on lower leaflets surface .Uredinia also can appear on the upper leaflets surface.	Long bean rust Causal agent : Uromyces vignae Symptoms : There are brownish spots on the leaves. When the rusb are touched it is like a brown dust.
Corn smut Causal agent : Ustilago maydis Symptoms : Abnormal enlargement of the kernels and the colour of the kernel become whitish grey.	Blister blight of tea Causal agent : Exobasidium vexans Symptoms : The early symptom is the development of transparent spot either round or oval in shape. Usually occur on the younger leaves. After several days, the spot will curved and the color will change to white.
Pink disease Causal agent : Corticium salmonicolor Symptoms : The early symptom is there will wounds on the stem which produce white latex. The fungi will grow and look like white thread. The mycillia will change into pink color.	Horse hair blight Causal agent : Marasmius equicrinus Symptoms : There are black fungal threads resembling horse hair that attack the upper branches and twigs.
White thread blight Causal agent : Marasmiellus scandens Symptoms : The young branches contain white mycelial threads of fungus.It spread longitudinally and irregularly along the surface of the stem.	White root disease Causal agent : Rigidoporus lignosus Symptoms : White rhizomorph seen on the root of tree.
Red root disease Causal agent : Ganoderma philipii Symptoms : The symptoms shown after a few years. The symptoms there are sheets of red mycellia that will together form rhizomorphs and connected to form membrane on the root.	Brown root disease Causal agent : Phellinus noxius Symptoms : The root that was attacked has sand and soil stick on it. It is due to the mycillia will form mucilage that will stick the sand and soil. The brown mycellia will spread and the it can be seen after the tree was long dead.
Vascular streak dieback of cocoa Causal agent : Oncobasidium theobromae Symptoms : The attack start at the shoot. The leaves on the shoot will turn into yellow and sometime they have green spot.The leaves will fall and when the bark of tree was thrown, the stem will turn into brownish colour immediately.	Basal stem rot of oil palm Causal agent : Ganoderma boninense Symptoms : The basidiocarpa will shown on the basal stem. The other symptom is the leaves of the coconut will die and it will hang on the tree and surround the stem of tree.