Diagnosis of Plant Disease. Chapter 3. Objective. Identify common plant diseases cause by microorganism Observing the symptoms and sign developed Capable to relate Koch’s Postulate principles. Symptoms and Signs. Symptoms : The visible response of a plant to a causal agent over time.
Symptoms : The visible response of a plant to a causal agent over time.
Swelling on Branches
Signs : The pathogen or its parts that seen on a host plant
Aphids on Plant
Yellowing of leaves due to:
Septoria Leaf Spot
Hyperplastic Deformation : Abnormal outgrowths of the plant host Hypertrophy: Overgrowth of plant organ or plant size because the increasing of cell sizes Hyperplasia : Overgrowth of plant organ or plant size because the increasing ofcell numbersor cell multiply rapidly. Both gave the same results to the plant where the size of plant tissue or plant organs increased than usual (abnormal size)
Root Knot – attack root
One or more members
of a plant are significantly
smaller than standard members
of their species
Hypotrophy : the under-development of plant organ or plant size because the reducing of cell sizes
Hypoplasia : the under-development of plant organ or plant size because the reducing of cell numbers