That is chlorosis? It is a yellowing and/or bleaching phenomenon especially on the leaf of a plant.
This happens when the organelle chloroplasts responsible for photosynthesis, are deprived of the pigment chlorophylls that give the plant its color green.
To maintain the healthy state of chlorophylls sufficient amount of nutrients has to be supplied to the pigments at all time.
However, there are many factors that may cause deprivation of nutrients needed to maintain the chlorophyll. And these factors can be categorized to biotic and abiotic factors.
A biotic factors are causes that are brought about by non-pathogenic phenomena.
Nutrient availability and optimality are the primary source
