I think it's a deficiency of nitrates, which help plants to produce chlorophyll, and which is the pigment that turns leaves green, and without it, leaves can become yellow.
most often, a Nitrogen defishincy (sp?)
If it is just some of the older leaves this can be normal if it is all the leaves it is dead.
effect of light on gene action
A:any of genus (rhododendron) of widely cultivated shrubs and trees of the health family with a alternate leaves showy flowers.
The biggest cause of LCD yellowing is the use of improper cleaners on the screen.
pat loves lina c
mould
Mostly the combustion products & Tar associated with tobacco smoke that causes yellowing.
Yellow leaves are usually a sign of overwatering.
When burned, it creates a toxic chemical in the air which causes diarrhea.
Rhododendron, Pentanthera (deciduous) and Tsutsuji (evergreen) are the two types of azalea plants. The scientific name for a leaf is a leaf. There are 8 types of Rhododendrons. One type is azalea. There are two kinds of azaleas; deciduous and evergreen. One sheds its leaves in the fall (leaf abscission), one keeps them all year long.
They have a magnesium deficiency. Magnesium is a mineral that is important in making chlorophyll (the green pigment that makes leaves green.) So a lack of it means that the leaves go yellow.