internodo

Internodo, or internode, is the portion of a plant stem located between two consecutive nodes. Nodes are the points on a stem where leaves, buds, or branches attach, while the internode is the stretch of stem that separates them. The length of internodes influences the overall height and branching pattern of the plant.

Internode length varies widely among species and is affected by developmental stage and environmental conditions. Long internodes produce taller, more open plants, as seen in many grasses and climbing species, whereas short internodes lead to compact growth. Light availability is a major factor: shade conditions often trigger internode elongation (shade avoidance), while ample light can limit it. Hormones such as auxins and gibberellins promote elongation, whereas other factors like nutrition and water status modulate the response.

Anatomically, internodes are the stem segments that contain vascular tissues (xylem and phloem) and supporting tissues between the nodes. Growth is driven by the apical meristem at the tip and by buds at the nodes, which can form new shoots or branches when conditions permit.

Significance: Internode length is an important trait in agriculture and horticulture because it affects plant height, lodging risk, light interception, and canopy structure. Breeders may select for shorter internodes to improve stability in cereals and other crops, or longer internodes when rapid vertical growth is desired. Practices such as pruning, training, and spacing also influence the development of internodes in cultivated plants.