Explain the role of zinc and boron as the phytonutrient ?

Both boron and zinc are micro nutrients required by plants.  

Boron is required by plants for the following reasons.  

• Uptake and utilization of calcium ion
• Elongation of pollen tube during germination
•  Involved in nucleic acid synthesis so essential in cell division
• Involved in cell elongation and differentiation
• Carbohydrate translocation

Zinc ​is required by plants for the following reasons.  

Activates enzymes such as carboxylases
Participates in formation of  chlorophyll 
Required for ​synthesis of auxins​​