Formation of Secondary Walls in the Palisade Cells of the Seed Coat of Lima Bean

Abstract

Deposition of the secondary wall in the palisade cells of the testa of lima bean seeds appears to involve the endoplasmic reticulum primarily. Although the principal component of that wall is highly oriented and highly crystalline cellulose, virtually no microtubules appeared during cell growth and maturation. Some indications were found that ribosome aggregation in the cytoplasm was associated with the origin of lamellae of the endoplasmic reticulum. Ribosome-like bodies were also prominent at the plasmalemma during formation of the secondary wall.