skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: Photosynthetic leaf area modulates tiller bud outgrowth in sorghum: Bud outgrowth is sensitive to leaf area

Abstract

Shoot branches or tillers develop from axillary buds. The dormancy versus outgrowth fates of buds depends on genetic, environmental and hormonal signals. Defoliation inhibits bud outgrowth indicating the role of leaf-derived metabolic factors such as sucrose in bud outgrowth. In this study, the sensitivity of bud outgrowth to selective defoliation was investigated. At 6 d after planting (6 DAP), the first two leaves of sorghum were fully expanded and the third was partially emerged. Therefore, the leaves were selectively defoliated at 6 DAP and the length of the bud in the first leaf axil was measured at 8 DAP. Bud outgrowth was inhibited by defoliation of only 2 cm from the tip of the second leaf blade. The expression of dormancy and sucrose-starvation marker genes was up-regulated and cell cycle and sucrose-inducible genes was down-regulated during the first 24 h postdefoliation of the second leaf.At 48 h, the expression of these genes was similar to controls as the defoliated plant recovers. Our results demonstrate that small changes in photosynthetic leaf area affect the propensity of tiller buds for outgrowth. Therefore, variation in leaf area and photosynthetic activity should be included when integrating sucrose into models of shoot branching.

Authors:
 [1];  [1]
  1. Texas A & M Univ., College Station, TX (United States)
Publication Date:
Research Org.:
Univ. of Southern California, Los Angeles, CA (United States)
Sponsoring Org.:
USDOE
OSTI Identifier:
1345708
Alternate Identifier(s):
OSTI ID: 1345709; OSTI ID: 1454852
Grant/Contract Number:  
SC0009885
Resource Type:
Journal Article: Published Article
Journal Name:
Plant, Cell and Environment
Additional Journal Information:
Journal Volume: 38; Journal Issue: 8; Journal ID: ISSN 0140-7791
Publisher:
Wiley
Country of Publication:
United States
Language:
English
Subject:
59 BASIC BIOLOGICAL SCIENCES; axillary bud; defoliation; dormancy; shoot branching; sucrose; tillering; apical dominance

Citation Formats

Kebrom, Tesfamichael H., and Mullet, John E.. Photosynthetic leaf area modulates tiller bud outgrowth in sorghum: Bud outgrowth is sensitive to leaf area. United States: N. p., 2014. Web. doi:10.1111/pce.12500.
Kebrom, Tesfamichael H., & Mullet, John E.. Photosynthetic leaf area modulates tiller bud outgrowth in sorghum: Bud outgrowth is sensitive to leaf area. United States. doi:10.1111/pce.12500.
Kebrom, Tesfamichael H., and Mullet, John E.. Fri . "Photosynthetic leaf area modulates tiller bud outgrowth in sorghum: Bud outgrowth is sensitive to leaf area". United States. doi:10.1111/pce.12500.
@article{osti_1345708,
title = {Photosynthetic leaf area modulates tiller bud outgrowth in sorghum: Bud outgrowth is sensitive to leaf area},
author = {Kebrom, Tesfamichael H. and Mullet, John E.},
abstractNote = {Shoot branches or tillers develop from axillary buds. The dormancy versus outgrowth fates of buds depends on genetic, environmental and hormonal signals. Defoliation inhibits bud outgrowth indicating the role of leaf-derived metabolic factors such as sucrose in bud outgrowth. In this study, the sensitivity of bud outgrowth to selective defoliation was investigated. At 6 d after planting (6 DAP), the first two leaves of sorghum were fully expanded and the third was partially emerged. Therefore, the leaves were selectively defoliated at 6 DAP and the length of the bud in the first leaf axil was measured at 8 DAP. Bud outgrowth was inhibited by defoliation of only 2 cm from the tip of the second leaf blade. The expression of dormancy and sucrose-starvation marker genes was up-regulated and cell cycle and sucrose-inducible genes was down-regulated during the first 24 h postdefoliation of the second leaf.At 48 h, the expression of these genes was similar to controls as the defoliated plant recovers. Our results demonstrate that small changes in photosynthetic leaf area affect the propensity of tiller buds for outgrowth. Therefore, variation in leaf area and photosynthetic activity should be included when integrating sucrose into models of shoot branching.},
doi = {10.1111/pce.12500},
journal = {Plant, Cell and Environment},
number = 8,
volume = 38,
place = {United States},
year = {Fri Dec 12 00:00:00 EST 2014},
month = {Fri Dec 12 00:00:00 EST 2014}
}

Journal Article:
Free Publicly Available Full Text
Publisher's Version of Record at 10.1111/pce.12500

Citation Metrics:
Cited by: 13 works
Citation information provided by
Web of Science

Save / Share: