ZOYSIAGRASS EVALUATION FOR DNA CONTENT, STING NEMATODE RESPONSE, NITROGEN MANAGEMENT, AND ESTIMATES OF HERITABILITY FOR TURFGRASS PERFORMANCE TRAITS By BRIAN M. SCHWARTZ A DISSERTATION PRESENTED TO THE GRADUATE SCHOOL OF THE UNIVERSITY OF FLORIDA IN PARTIAL FULFILLMENT OF THE REQUIREMENTS FOR THE DEGREE OF DOCTOR OF PHILOSOPHY UNIVERSITY OF FLORIDA 2008 1 © 2008 Brian M. Schwartz 2 To Süz 3 ACKNOWLEDGMENTS I would like to express my sincere appreciation to Dr. Kevin Kenworthy, the members of my advisory committee, the Agronomy Department, and the staff at the Plant Science Research and Education Unit for all of the guidance, support, and help. Thanks are also in order for the generous donation of laboratory equipment from Mark Kann and the Seven Rivers Golf Course Superintendents Association. This research would not have been possible without these efforts. 4 TABLE OF CONTENTS page ACKNOWLEDGMENTS ...............................................................................................................4 LIST OF TABLES...........................................................................................................................7 LIST OF FIGURES .........................................................................................................................9 ABSTRACT...................................................................................................................................12 CHAPTER 1 INTRODUCTION ..................................................................................................................14 2 VARIATION IN 2C NUCLEAR DNA CONTENT OF Zoysia spp. AS DETERMINED BY FLOW CYTOMETRY.....................................................................................................17 Introduction.............................................................................................................................17 Materials and Methods ...........................................................................................................20 Plant Materials.................................................................................................................20 Flow Cytometry...............................................................................................................20 Morphological Measurements.........................................................................................21 Statistical Analysis ..........................................................................................................21 Results and Discussion ...........................................................................................................22 Conclusions.............................................................................................................................24 3 EFFICIENT METHODOLOGY FOR SCREENING STING NEMATODE RESPONSE IN A TURFGRASS BREEDING PROGRAM ......................................................................28 Introduction.............................................................................................................................28 Materials and Methods ...........................................................................................................30 Results.....................................................................................................................................34 Discussion...............................................................................................................................36 4 VARIABLE RESPONSES OF ZOYSIAGRASS, ST. AUGUSTINEGRASS, AND BERMUDAGRASS GENOTYPES TO THE STING NEMATODE....................................46 Introduction.............................................................................................................................46 Materials and Methods ...........................................................................................................48 Results and Discussion ...........................................................................................................51 Conclusions.............................................................................................................................55 5 5 MOWING HEIGHT AND NITROGEN FERTILITY MANAGEMENT OF ZOYSIAGRASS IN FLORIDA .............................................................................................59 Introduction.............................................................................................................................59 Materials and Methods ...........................................................................................................61 Results and Discussion ...........................................................................................................63 Zoysia japonica ...............................................................................................................63 Zoysia matrella................................................................................................................66 Conclusions.............................................................................................................................69 6 HERITABILITY ESTIMATES FOR TURFGRASS PERFORMANCE AND STRESS RESPONSE IN Zoysia spp.....................................................................................................97 Introduction.............................................................................................................................97 Materials and Methods .........................................................................................................100 Results and Discussion .........................................................................................................103 Conclusions...........................................................................................................................106 REFERENCES ............................................................................................................................113 BIOGRAPHICAL SKETCH .......................................................................................................127 6 LIST OF TABLES Table page 2-1 Means for 2C nuclear DNA content and leaf blade width of zoysiagrass genotypes for five species and five interspecific hybridizations ........................................................26 3-1 Mean squares for Belonolaimus longicaudatus reproduction factor (Rf), final population density (Pf), population density on a total root length basis (Pf/TRL), population density on a total dry root basis (Pf/TDRW), total dry root weight (TDRW), total dry root weight percent reduction (TDRW % red.), total root length (TRL), total root length percent reduction (TRL % red.), fine root length (FRL), and fine root length percent reduction (FRL % red.) of TifEagle bermudagrass evaluated in three establishment (Est.) methods with different inoculation treatments (Inoc. TRT) in two experimental trials.........................................................................................41 3-2 Mean reproduction factor (Rf), final population density (Pf), population density on a total root length basis (Pf/TRL), population density on a total dry root basis (Pf/TDRW), of Belonolaimus longicaudatus on TifEagle bermudagrass 90 days after inoculation evaluated in three establishment methods with two inoculation treatments in two experimental trials...................................................................................................42 3-3 45-d and 90-d conetainer (above diagonal) and 90-d clay pot (below diagonal) correlation coefficients of Belonolaimus longicaudatus reproduction factor (Rf), final population density (Pf), population density on a total root length basis (Pf/TRL), population density on a total dry root weight basis (Pf/TDRW), total dry root weight (TDRW), total dry root weight percent reduction (TDRW % red.), total root length (TRL), total root length percent reduction (TRL % red.), fine root length (FRL), and fine root length percent reduction (FRL % red.) of TifEagle bermudagrass.....................43 3-4 Mean total dry root weight (TDRW), total dry root weight percent reduction (TDRW % red.), and total root length (TRL) of TifEagle bermudagrass 90 days after inoculation evaluated in three establishment methods with uninoculated and inoculated treatments in two experimental trials. ..............................................................44 3-5 Mean total root length percent reduction (TRL % red.), fine root length (FRL), and fine root length percent reduction (FRL % red.) of TifEagle bermudagrass 90 days after inoculation evaluated in three establishment methods with uninoculated and inoculated treatments in two experimental trials. ..............................................................45 4-1 Mean squares for Belonolaimus longicaudatus reproduction factor (Rf), total root length (TRL), and total dry root weight (TDRW) of six turfgrasses evaluated in two establishment (Est.) methods with uninoculated and inoculated treatments (Inoc. TRT) in two experimental trials.........................................................................................57 4-2 Mean reproduction factor (Rf) of Belonolaimus longicaudatus on six turfgrasses 90 days after inoculation with 50 B. longicaudatus, evaluated in 45-d conetainers and 90-d conetainers in two experimental trials.......................................................................57 7 4-3 Mean total root length (TRL) and total