ACTION OF AUXIN ON LEAF ABSCISSION
Abstract
Experiments have been conducted to investigate a two-stage effect of auxin on abscission. The two stages were demonstrated on greenhouse-grown Black Valentine beans by applying IAA (1000 ppm in lanolin) to cut ends of the petioles of primary leaves at various times after deblading. An application immediately after deblading inhibits petiole abscission while the same IAA concentration applied 24 hours after deblading markedly promotes abscission. Using the same abscission test, it was found that abscission of a debladed petiole was inhibited when the opposite primary leaf was left intact. When IAA was substituted for the leaf blade, abscission of the petiole upon which it was applied was inhibited while abscission of the opposite petiole was markedly promoted. However, when IAA was applied to a debladed petiole and the opposite leaf was not debladed until 48 hours later, both petioles were inhibited, thus suggesting that when both leaves were debladed simultaneously the applied IAA affected the opposite petiole after it had reached the second stage - the stage which is stimulated by auxin. Similar experiments were performed with petioles of various lengths and ages. The implications of these results indicate possible sites of auxin action on leaf abscission. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- Oct 01, 1963
- Accession Number
- AD0422351
Entities
People
- Bernard Rubinstein
Organizations
- United States Army Biological Warfare Laboratories