Influence of Boll Removal on Assimilate Partitioning in Cotton1

Abstract

Field experiments with Upland cotton (Gossypium hirsutum L.) were initiated to determine the effect of boll removal on the distribution of 14C‐assimilates 24 hours following removal. The mainstem leaf subtending the sympodium supplied the first and second boll positions with assimilates. In the absence of bolls, assimilates in the mainstem leaf moved basipetally from the leaf subtending the first position. The majority of assimilates were translocated to the first position boll. Removal of the first position boll resulted in assimilate movement to the second position parts of the plant when the second position was 10 days old. The majority of the assimilates from the second position leaf, being further out on the sympodium, remained in the sympodium, as long as at least one fruiting body was present. Removal of all the bolls from the sympodium resulted in translocation primarily in a basipetal direction.