Published in JOURNAL OF PLANT REGISTRATIONS 2:51-52 (2008)
DOI: 10.3198/jpr2007.03.0168crg
© 2008 Crop Science Society of America
677 S. Segoe Rd., Madison, WI 53711 USA
GERMPLASMS
Registration of Large, Erect Pensacola Bahiagrass Germplasm Lines T18 and T23
G. W. Burton and
W. F. Anderson*
USDA-ARS, Crop Genetics and Breeding Research Unit, P.O. Box 748, Tifton, GA 31793
* Corresponding author (bill.anderson{at}ars.usda.gov).
‘Pensacola’ bahiagrass (Paspalum notatum Flügge) germplasm lines T18 (Reg. No. GP-3, PI 648217) and T23 (Reg. No. GP-4, PI 648218) were jointly released by the Agricultural Research Service, United States Department of Agriculture and the University of Georgia College of Agricultural and Environmental Sciences, Coastal Plain Experiment Station in Tifton in 2007. T18 and T23 bahiagrass germplasm lines have larger, more erect plants and higher individual plant yields, than Pensacola. They have value as parents in development of high-yielding bahiagrass cultivars for pasture and hay production.
T18 and T23 are a result of 18 and 23 cycles of recurrent restricted phenotypic selection (RRPS), respectively, for individual plant size and yield from ‘Pensacola’ (Burton 1974; 1982). For each cycle, 20% of 1000 space-planted selections from the previous cycle were selected based on above-ground herbage accumulation. In December, 125 seeds of each entry were planted in rows in flats of soil in the greenhouse. In February, the seven most vigorous seedlings were transplanted to 5-cm clay pots in the greenhouse. In April, land was prepared in the field by fumigating with methyl bromide and the six most vigorous plants of the 166 best (largest and best established) entries were planted on 6-m centers in six blocks. In July, five plants having inflorescences and having the longest leaves within each 5 x 5 block were selected. Three culms from each selection were labeled and placed together in a common vessel filled with water in isolation. Inflorescences were shaken each morning to ensure inter-pollination. Harvested seed produced were used for the next cycle in the greenhouse and transplanted to the field for selection the following spring.
To evaluate the change in individual plant characteristics of the ninth (T9), eighteenth (T18), and twenty-third (T23) cycles of selection from Pensacola, spaced seedlings were planted on 6 May 1998 in the field at Tifton, GA with Pensacola and five other entries (total nine entries). Two tests were planted with each having 18 plants from each entry. Plants were spaced at 17.6 cm and 26.4 cm in the two tests in a ‘Design 3’ orientation. A Design 3 randomizes the nine entries in a 3 x 3 arrangement to form a lattice square block and nine blocks (replications) are then arranged 3 x 3 similar to a ‘Sudoku’ puzzle orientation. Two Design 3 patterns were aligned end to end to constitute the 18 replications for each spaced plant test. Individual plant dry matter yield, plant height, and plant diameter were measured on 8 October for the 17.6 cm spacing test and on 13 October for the 26.4 cm spacing test.
Individual plant phenotype data was recorded on 100 plants each of Tifton 9, T18, and T23 in 2005. Seeds were started in the greenhouse and transplanted to 2-cm clay pots. The culm number was counted four weeks after germination (17 May 2005) and plants were then transplanted to the field. Plants of each entry were space planted 26.4 cm apart in a single bed at Tifton, GA. Culm angle as measured as degrees from ground (ground level = 0, completely erect = 90) of the lowest culm to the ground, plant height (ground to base of terminal culm), leaf length (third leaf from culm terminal), and leaf width (third leaf from culm terminal) were recorded on 30 June 2005. Raceme number (average of three inflorescences) and raceme length (average of longest raceme on three inflorescences) were measured on July 15, 2005.
Plant dry matter yield, plant height and plant diameter of T23 was significantly greater (p = 0.05) than Pensacola and T9 bahiagrass while T18 was intermediate in both tests (Tables 1
and 2
) which supports previous data (Pedreira and Brown, 1996; Werner and Burton, 1991). Plants of T18 and T23 had a more erect plant phenotype than Pensacola or Tifton 9 (Burton, 1989) bahiagrasses.
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Table 1. Dry matter yield, plant height, and plant diameter of individual plants of bahiagrass spaced 17.6 cm apart in as Design 3 randomized plot arrangement with 18 replications planted 6 May 1998 and harvested 8–9 October 1998.
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Table 2. Dry matter yield, plant height, and plant diameter of individual plants of bahiagrass spaced 26.4 cm apart in randomized Design 3 plot arrangement with 18 replications planted 6 May 1998 and harvested 13–14 October 1998.
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Mature plants of T18 and T23 had significantly fewer culms (8.1 and 6.3, respectively) than Tifton 9 (9.2) in field comparisons of 100 individual spaced plants in 2005 (Table 3
). Culm angles from horizontal were significantly greater for T18 (46°) and T23 (55°) than for Tifton 9 (34o) indicating more erect plant types. Plant heights and leaf lengths were greater for T18 and T23 than Tifton 9; however, leaf width of the germplasm lines were less than Tifton 9. Inflorescences had generally three racemes. Raceme lengths of T18 and Tifton 9 were similar, whereas T23 racemes were shorter (Table 3).
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Table 3. Comparative means for morphological traits between Tifton 9, T 18, and T 23 on 100 individual spaced plants in field Tifton, GA 2005.
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Seeds of T18 and T23 will be deposited in the USDA-ARS National Plant Germplasm System. Breeder seed will be maintained by USDA-ARS Crop Genetics and Breeding Research Unit at Tifton. Small quantities of seed may be obtained from W. F. Anderson at the USDA/ARS location in Tifton (Requests made to P.O. Box 748, Tifton, GA 31793).
Footnotes
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. Permission for printing and for reprinting the material contained herein has been obtained by the publisher.
Received for publication March 23, 2007.
References
- Burton, G.W. 1974. Recurrent restricted phenotypic selection increases forage yields of Pensacola bahiagrass. Crop Sci. 14:831–835.[Abstract/Free Full Text]
- Burton, G.W. 1982. Improved recurrent restricted phenotypic selection increases bahiagrass forage yields. Crop Sci. 22:1058–1061.[Abstract/Free Full Text]
- Burton, G.W. 1989. Registration of ‘Tifton 9’ Pensacola bahiagrass. Crop Sci. 29:1326.[Free Full Text]
- Pedreira, C.G.S., and R.H. Brown. 1996. Physiology, morphology, and growth of individual plants of selected and unselected bahiagrass populations. Crop Sci. 36:138–142.[Abstract/Free Full Text]
- Werner, B.K., and G.W. Burton. 1991. Changes in morphology and yield of Pensacola bahiagrass due to recurrent restricted phenoyptic selection for yield. Crop Sci. 31:48–50.[Abstract/Free Full Text]
