Question

what reasons can be there for slow growth of plants with chlorotic leaves

Answer 1

Chlorosis is a yellowing of leaf tissue due to a lack of chlorophyll. Possible causes of chlorosis include poor drainage, damaged roots, compacted roots, high alkalinity, and nutrient deficiencies in the plant. Nutrient deficiencies may occur because there is an insufficient amount in the soil or because the nutrients are unavailable due to a high pH (alkaline soil). Or the nutrients may not be absorbed due to injured roots or poor root growth.
The lack of iron is one of the more common nutrients associated with chlorosis. Plants need iron for the formation of chlorophyll. Chlorophyll gives leaves their green color and is necessary for the plant to produce the food it needs for its own growth. Iron is also necessary for many enzyme functions that manage plant metabolism and respiration. Iron becomes more insoluble as the soil pH climbs above 6.5 to 6.7 (7.0 is neutral - below 7.0, the pH is acidic; above 7.0, the pH is alkaline). With most plants, iron can only be absorbed as a free ion (Fe++) when the pH is between 5.0 and 6.5.

So you can simply understand that due to Chlorosis Leaves are unable to Prepare enough food by Photosynthesis. So Growth of Plant is Affected.

I hope this answer satisfied you.