Submitted to: Agronomy Journal
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: January 3, 2002
Publication Date: July 31, 2002
Interpretive Summary: Production of cotton varieties occurs through the selective crossing of parental lines. Hybrid production is commonly preceded by the removal of the male reproductive structures from recipient flowers. The mechanical removal of the reproductive structures is time consuming, results in tissue injury, and may result in reduced boll retention. The purpose of this study was to develop a protocol for the functional removal of the mal reproductive structures that was rapid, did not result in female sterility, and maintained fruit retention. A protocol was developed that used water to osmotically destroy cotton pollen on the day of pollination. The procedure provided male sterility without modification of the reproductive capacity of the cotton flower.
Technical Abstract: Production of cotton (Gossypium hirsutum L.) hybrids is commonly preceded by the removal of the anthers from recipient flowers. The mechanical removal of the anthers is time consuming, results in tissue injury, and may result in reduced fruit retention. The purpose of this study was to develop an emasculation protocol that was rapid, did not result in female sterility, and maintained fruit retention. Treatment of cotton flowers with water as the pollen dehisced resulted in the osmotic disruption of the pollen grains and prevented self-pollination of the cotton flowers. Morphological analysis of isolated pollen grains before and after water treatment showed the exudation of pollen cytoplasm into the surrounding water medium within seconds of the water treatment. The water treatment resulted in the loss of fruiting bodies unless the flowers were subsequently pollinated with viable pollen. The bolls that were set following hand pollination of water emasculated flowers produced seed numbers equivalent to self-pollinated controls.