CHANGES IN DISTRIBUTION OF ROOTS OF BANANA (MUSA AAA CV VALERY) WITH PLANT HEIGHT, DISTANCE FROM THE PSEUDOSTEM, AND SOIL DEPTH

The distribution of roots in banana was determined on a sandy clay loa m in Costa Pica. Samples were taken from soil blocks at distances of 0 to 30, 30 to 60, and 60 to 90 cm from the pseudostem, 0 to 120 cm dep th at intervals of 15 cm, and from plants that were 120, 150, 180 or 2 10 cm tall (non-flowering), plus a set from plants with emergent flowe r stalks. Plant height and the horizontal distance from the pseudostem did not affect the percentage of fresh root weight. In contrast, ther e was a significant effect of soil depth, and a significant interactio n between soil depth x horizontal distance from the pseudostem, on the percentage of fresh root weight. For the three distances from the pse udostem, the percentage of root weight decreased sharply with soil dep th. Independently of the distance from the pseudostem, all plants show ed the highest root weight in the top 15 cm of soil. More than 65% of the total root weight was found in the upper 30 cm of soil. More than 79% and 88% of the roots were detected in the first 45 and 60 cm of th e soil profile at any plant height, respectively. The total fresh root weight in the excavated area (0-90 cm from the pseudostem and 0-120 c m depth) was 1.16, 0.97, 1.14, 1.50, and 1.22 kg in the plant heights of 120, 150, 180 and 210 cm, and plants with emergent flower stalks, r espectively. Additional studies of root stratification patterns are ne cessary for a better understanding of the interaction between cultural practices and crop yield.