Boron Deficiency in Cassava
When cassava are boron deficient, plants are typically short because of reduced internodes. Young leaves are normally dark green, small and deformed, and carried on short petioles. Lower mature leaves may be flecked with grey, brown, or purple spots near the tip and margins. Resin may exude from lesions on petioles. Root growth is suppressed. Ultimately the growing point dies.