Boron deficiency-Melons

Symptoms
Young leaves are smaller than normal and may be curled. Yellowing proceeds from the marginal area between the veins towards the center. The youngest leaves show necrotic tips. Stems can crack due to the low cell strength. Plants are stunted or dwarfed as the internodes are shortened. Growing points die back. Flowering and fruit set is poor. Fruits are distorted with a poor skin finish. Hollow heart is more common.

Reasons
Boron deficiency. Deficiencies usually occur when soil moisture contents are too high, or under conditions of high pH.