HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Figures Only Full Text Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Similar articles in this journal Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via Google Scholar Google Scholar Articles by Su, K. Articles by Fry, J. D. Search for Related Content PubMed Articles by Su, K. Articles by Fry, J. D. Agricola Articles by Su, K. Articles by Fry, J. D. Related Collections Turfgrass Management Water Stress Plant and Environment Interactions Root Development Irrigation

TURFGRASS

Rooting Characteristics and Canopy Responses to Drought of Turfgrasses Including Hybrid Bluegrasses

Dep. of Horticulture, Forestry & Recreation Resources, 2021 Throckmorton Hall, Kansas State Univ., Manhattan, KS 66506. Contribution no. 08-221-J from the Kansas Agric. Exp. Station

^* Corresponding author (bremer{at}ksu.edu).

Drought stress is common among cool-season turfgrasses during summer in the U.S. transition zone. A 2-yr field study was conducted near Manhattan, KS, to evaluate rooting characteristics and effects of drought on canopy physiology and appearance of ‘Apollo’ Kentucky bluegrass (Poa pratensis L.) (KBG), ‘Dynasty’ tall fescue (Festuca arundincea Schreb.) (TF), and two hybrid bluegrasses (HBG) ‘Reveille’ and ‘Thermal Blue’; HBG are genetic crosses between native Texas bluegrass (P. arachnifera Torr.) and KBG. Rooting characteristics were measured in the field and greenhouse under well-watered conditions to evaluate root contributions to drought avoidance. Two irrigation treatments in the field included: (i) 60% (water-deficit); and (ii) 100% (well-watered) evapotranspiration (ET) replacement. Ninety to 96% of all root length (0–80 cm) in the field and 74 to 80% of all root length (0–120 cm) in the greenhouse were in the upper 30 cm among Thermal Blue, Reveille, and KBG while in TF, only 86 and 70% of all root length in the field and greenhouse, respectively, were in the top 30 cm. In the field, tall fescue had 3 to 12 times greater root length in the lower profile (60–80 cm) among turfgrasses. Visual quality and gross photosynthesis (P_g) were greatest in TF among turfgrasses in both irrigation treatments. Reveille used more water from the 0 to 50 cm profile and performed better than Thermal Blue during water-deficit, but both HBG recovered from water-deficit slightly faster than KBG. Performances in visual quality and P_g generally ranked: TF > Reveille Thermal Blue = KBG.

Abbreviations: DOT, days of treatment • DPHP, dual-probe heat pulse • ET, evapotranspiration • HBG, hybrid bluegrass • HBG1, Thermal Blue- a HBG • HBG2, Reveille- a HBG • KBG, Kentucky bluegrass • MRE, maximum root extension • P_g, gross photosynthesis • RLD, root length density • TDR, time domain reflectometry

All rights reserved. No part of this periodical may be reproduced or transmitted in any form or by any means, electronic or mechanical, including photocopying, recording, or any information storage and retrieval system, without permission in writing from the publisher.

Received for publication August 30, 2007.