Role: Auxin synthesis, internode elongation, leaf size, and flower formation.

Deficiency: Small leaves, rosette appearance, reduced flowering, poor fruit set.

Management: Foliar spray of Zinc Sulphate (0.5%) + lime.

(b) Boron (B)

Role: Pollen germination, fruit set, sugar transport, uniform fruit development.

Deficiency: Poor fruit set, hard lumpy fruits, cracking, deformed fruits.

Management: Foliar spray of Borax (0.1–0.2%) or soil application (1–2 kg/acre).

(c) Iron (Fe)

Role: Chlorophyll formation and respiration.

Deficiency: Interveinal chlorosis (yellowing) in young leaves, stunted growth.