The main structures of the plant are the coleoptile, leaves, stalk, roots, ear and tassel. Unlike all other major grain crops, the maize plant has separate male and female flowering structures – the tassel and the ear. When both flowering structures are located on the same plant, as they are in maize, the plant is called monoecious.

Coleoptile

The coleoptile is a pointed, modified leaf that surrounds and protects the plumule (four or five leaves rolled up, one inside the other) during germination. Such protection is valuable as the coleoptile elongates, pushing the plumule through the covering of the kernel (pericarp) and then through the soil to the surface.

Leaves

The leaf (Figure viii) consists of the leaf blade, leaf midrib and leaf collar and sheath. Leaves are produced in a set order on alternate sides of the stem.The leaf blade is the nearly flat part of the leaf where the process of photosynthesis occurs. The leaf midrib extends the length of the middle of the leaf blade from the base to the tip. It provides structural support. The collar is the area on the inner surface of the leaf where the leaf blade and leaf sheath join. The sheath is the leaf portion (below the collar) that wraps around a stalk and attaches the leaf to a stalk node.

The stalk

The stem is made up of nodes and internodes and provides structural support for the leaves to intercept sunlight.

The roots

The root system consists of lateral seminal roots, nodal roots and brace roots. The lateral roots grow directly from the kernel. These roots provide anchorage.

Regards

Joseph Mareddy

Assistant Managing Editor

Journal of Plant Biochemistry and physiology