Figures (3)  Tables (3)

    • Figure 1. 

      Histograms of best linear unbiased predictions (BLUEs) for winter survival traits in St. Augustinegrass Raleigh selfing population. The red triangle indicates the value for cultivar Raleigh. H2 = heritability, PGC = Percent green cover, UPGC = UAS-derived percentage green cover, FC = fall color, WI = winter injury, WK = winterkill, Antho = anthocyanin rating, chla = chlorophyll a, chlb = chlorophyll b, caro = carotenoids, antho = lab-assayed anthocyanin. The '_all' indicates traits across three years, while postpositive numbers 1, 2, and 3 indicate sample collection dates on September 21, September 28, and October 12, 2023, respectively.

    • Figure 2. 

      Pearson correlation coefficients for winter survival traits in a St. Augustinegrass Raleigh selfing population evaluated in 2021, 2022, and 2023 field trials and lab-assays. PGC = Percent green cover, UPGC = UAS-derived percent green cover, FC = fall color, WI = winter injury, WK = winterkill, Antho = anthocyanin rating, chla = chlorophyll a, chlb = chlorophyll b, caro = carotenoids, antho = lab-assayed anthocyanin. The 21, 22, 23, and _all on the trait column indicate years 2021, 2022, 2023, and across three years, whereas 1, 2, and 3 indicate sample collection dates September 21, September 28, and October 12, 2023, respectively. ***, **, and * indicate significance at 0.001, 0.01, and 0.05 probability levels, respectively.

    • Figure 3. 

      Single-nucleotide polymorphism (SNP)-based linkage map generated for a St. Augustinegrass Raleigh selfing population. cM = centimorgan.

    • LG Length (cM) # of markers # of markers·cM−1 Max gap (cM)
      1 230.14 242 1.05 11.66
      2 315.96 308 0.97 10.24
      3 253.85 246 0.97 8.72
      4 201.86 216 1.07 8.82
      5 284.56 298 1.05 10.95
      6 191.41 180 0.94 7.35
      7 184.28 205 1.11 9.8
      8 213.89 180 0.84 11.88
      9 313.65 337 1.07 9.69
      Total 2,189.6 2,212
      Average 245 1.01 9.9
      LG: Linkage group; cM: centimorgan.

      Table 1. 

      Summary of linkage groups generated from a St. Augustinegrass Raleigh selfing population.

    • # Trait QTL LG Peak position (cM) Confidence interval (cM) Peak marker PVE (%) p-value
      1 WK21 WK21_1_39.61 1 39.61 37.42−43.04 SRM_chr1_9390807 9.32 1.76E-04
      2 WI_all WI_all_1_39.61 1 39.61 37.42−140.47 SRM_chr1_9390807 10.63 2.42E-04
      3 WI21 WI21_1_39.61 1 39.61 39.61−227.2 SRM_chr1_9390807 10.42 1.12E-07
      4 Antho23 Antho23_1_136.38 1 136.38 124.1−154.2 SRM_chr1_28009546 12.25 1.11E-07
      5 WK_all WK_all_1_199.42 1 199.42 199.42−227.2 SRM_chr1_39468139 9.59 6.85E-06
      6 UPGC23 UPGC23_1_222.03 1 222.03 213.88−230.14 SRM_chr1_41412375 11.02 1.99E-04
      7 FC21 FC21_2_19.41 2 19.41 18.03−19.41 SRM_chr2_6118190 17.52 5.47E-06
      8 PGC23 PGC23_2_56.22 2 56.22 52.57−57.18 SRM_chr2_11185619 12.76 1.08E-05
      9 WI23 WI23_2.1_82.87 2 82.87 82.87−86.41 SRM_chr2_14436196 31.19 1.91E-06
      10 WK23 WK23_2.1_84.13 2 84.13 82.87−86.41 SRM_chr2_15049957 43.57 6.48E-07
      11 WI_all WI_all_2.1_93.21 2 93.21 88.26−184.09 SRM_chr2_23379451 24.17 1.55E-07
      12 WK23 WK23_2.2_210.51 2 210.51 145.34−226.12 SRM_chr2_37567147 24.89 5.13E-07
      13 chlb1 chlb1_2.1_212.66 2 212.66 162.12−313.38 SRM_chr2_38817526 23.73 7.84E-05
      14 chlb3 chlb3_2_260.13 2 260.13 164.22−307.1 SRM_chr2_46125769 25.84 2.85E-07
      15 WI23 WI23_2.2_265.09 2 265.09 194.27−290.51 SRM_chr2_46570579 13.71 2.97E-06
      16 PGC22 PGC22_2_290.51 2 290.51 198.64−290.51 SRM_chr2_49032312 8.3 1.38E-10
      17 chla1 chla1_2.2_289.34 2 289.34 224.21−308.32 SRM_chr2_48536755 29.74 4.94E-05
      18 WI_all WI_all_2.2_265.09 2 265.09 251.36−308.32 SRM_chr2_46570579 16.1 2.22E-05
      19 FC_all FC_all_3_200.42 3 200.42 48.3−211.17 SRM_chr3_47495258 30.42 2.26E-06
      20 FC22 FC22_3_66.58 3 66.58 65.43−123.03 SRM_chr3_11211052 35.3 3.35E-05
      21 UPGC_all UPGC_all_3_151.83 3 151.83 151.83−154.35 SRM_chr3_39319376 18.72 8.02E-07
      22 WK21 WK21_3_153.75 3 153.75 151.83−156.35 SRM_chr3_40124103 9.9 3.53E-05
      23 UPGC23 UPGC23_3_153.75 3 153.75 151.83−156.35 SRM_chr3_40124103 18.53 < 2.22e-16
      24 PGC21 PGC21_3_157.76 3 157.76 151.83−157.76 SRM_chr3_41729219 9.7 6.15E-05
      25 PGC_all PGC_all_3_151.83 3 151.83 151.83−157.76 SRM_chr3_39319376 19.19 4.45E-10
      26 FC23 FC23_3_151.83 3 151.83 151.83−205.36 SRM_chr3_39319376 22.82 9.65E-09
      27 PGC23 PGC23_3_219.58 3 219.58 151.83−243.58 SRM_chr3_48803614 20.75 5.59E-06
      28 PGC22 PGC22_3_153.75 3 153.75 153.75−156.35 SRM_chr3_40124103 13.9 6.76E-09
      29 UPGC23 UPGC23_4_25.74 4 25.74 25.74−65.3 SRM_chr4_4064614 8.11 5.31E-06
      30 chlb2 chlb2_4_72.07 4 72.07 52.42−72.07 SRM_chr4_11638664 31.01 2.54E-09
      31 caro2 caro2_4_72.07 4 72.07 60.32−72.07 SRM_chr4_11638664 24.5 7.74E-06
      32 WI21 WI21_5.1_61.37 5 61.37 18.83−85.36 SRM_chr5_4532613 14.93 4.48E-06
      33 WK21 WK21_5.1_63.37 5 63.37 61.37−85.36 SRM_chr5_5048913 14.54 2.29E-04
      34 WI23 WI23_5_99.11 5 99.11 99.11−244.5 SRM_chr5_14502422 18.99 2.99E-10
      35 antho2 Antho2_5_160.43 5 160.43 152.07−240.19 SRM_chr5_37181648 35.31 2.99E-04
      36 Antho23 Antho23_5_196.37 5 196.37 154.67−241.6 SRM_chr5_39352795 45.67 2.99E-05
      37 antho1 Antho1_5_173.6 5 173.6 156.33−284.56 SRM_chr5_38134847 14.85 2.45E-06
      38 PGC22 PGC22_5.1_232 5 232 168.53−252.22 SRM_chr5_43448836 14.98 3.30E-06
      39 UPGC23 UPGC23_5_220.07 5 220.07 196.37−223.11 SRM_chr5_40575780 11.08 2.74E-04
      40 FC23 FC23_5_241.6 5 241.6 219.18−257.7 SRM_chr5_44493346 15.86 1.37E-05
      41 WK21 WK21_5.2_243.64 5 243.64 219.18−261.42 SRM_chr5_44875972 21.13 < 2.22e-16
      42 WI21 WI21_5.2_261.42 5 261.42 219.18−262.28 SRM_chr5_45788290 14.63 3.66E-05
      43 WI_all WI_all_5_244.5 5 244.5 243.64−262.28 SRM_chr5_44915179 23.01 2.51E-06
      44 WK_all WK_all_5_262.28 5 262.28 243.64−262.28 SRM_chr5_45875290 19.22 3.36E-08
      45 PGC22 PGC22_5.2_282.62 5 282.62 259.85−282.62 SRM_chr5_47222430 21.23 2.54E-10
      46 UPGC_all UPGC_all_5_282.62 5 282.62 261.42−282.62 SRM_chr5_47222430 15.32 1.87E-07
      47 UPGC22 UPGC22_5_282.62 5 282.62 282.62−282.62 SRM_chr5_47222430 20.37 1.70E-07
      48 WK_all WK_all_6_29.44 6 29.44 29.44−32.81 SRM_chr6_3624841 12.79 1.53E-06
      49 Antho23 Antho23_6_99.16 6 99.16 31.21−103.19 SRM_chr6_24263583 20.53 3.35E-06
      50 UPGC21 UPGC21_6_34.57 6 34.57 32.81−35.02 SRM_chr6_4576858 31.06 3.72E-05
      51 PGC21 PGC21_6_34.57 6 34.57 33.95−79.57 SRM_chr6_4576858 17.83 1.64E-04
      52 antho1 Antho1_6_86.51 6 86.51 72.04−86.51 SRM_chr6_22598764 26.53 2.50E-08
      53 FC21 FC21_6_190.63 6 190.63 180.1−191.41 SRM_chr6_35405719 23.26 1.47E-07
      54 UPGC21 UPGC21_7_18.21 7 18.21 13.32−86.16 SRM_chr7_16262976 20.03 8.40E-05
      55 PGC21 PGC21_7_85.86 7 85.86 13.32−132 SRM_chr7_26305257 12.83 1.67E-06
      56 UPGC_all UPGC_all_7_96.1 7 96.1 60.47−96.1 SRM_chr7_28936515 15.87 2.53E-04
      57 UPGC22 UPGC22_7_96.1 7 96.1 96.1−96.1 SRM_chr7_28936515 27.84 6.75E-05
      58 PGC21 PGC21_7_167.36 7 167.36 165.24−167.36 SRM_chr7_39266940 22.42 7.05E-07
      59 WI21 WI21_8_14.55 8 14.55 5.52−37.66 SRM_chr8_8316315 11.24 2.03E-04
      60 WK_all WK_all_8.1_101.39 8 101.39 101.39−101.39 SRM_chr8_24945032 25.2 8.90E-05
      61 Antho23 Antho23_8_210.16 8 210.16 165.96−213.89 SRM_chr8_60206545 5.12 2.98E-06
      62 WK_all WK_all_8.2_205.74 8 205.74 191.44−205.74 SRM_chr8_59350361 13.05 2.95E-06
      63 PGC23 PGC23_9.1_10.68 9 10.68 0−54.34 SRM_chr9_2522286 16.34 2.36E-04
      64 FC23 FC23_9.1_13.94 9 13.94 1.19−54.34 SRM_chr9_3008721 15.88 1.93E-05
      65 UPGC23 UPGC23_9.1_10.68 9 10.68 8.11−10.68 SRM_chr9_2522286 19.54 2.34E-09
      66 UPGC_all UPGC_all_9.1_10.68 9 10.68 10.68−27.86 SRM_chr9_2522286 18.92 7.13E-06
      67 FC21 FC21_9_28.57 9 28.57 10.68−28.57 SRM_chr9_3350841 21.25 8.63E-08
      68 PGC_all PGC_all_9.1_10.68 9 10.68 10.68−28.57 SRM_chr9_2522286 12.45 1.97E-06
      69 PGC22 PGC22_9.1_27.86 9 27.86 10.68−29.28 SRM_chr9_3275160 8.56 1.46E-04
      70 WI21 WI21_9_28.57 9 28.57 10.68−82.35 SRM_chr9_3350841 19.22 8.63E-08
      71 antho1 Antho1_9_179.42 9 179.42 59.39−180.05 SRM_chr9_39970748 17.02 5.37E-06
      72 PGC21 PGC21_9_88.25 9 88.25 72.64−99.87 SRM_chr9_13505054 10.08 1.03E-04
      73 WK21 WK21_9_82.35 9 82.35 76.88−82.35 SRM_chr9_12605602 19.04 2.54E-08
      74 PGC22 PGC22_9.2_211.37 9 211.37 179.42−253.02 SRM_chr9_42699215 8.93 4.47E-08
      75 chlb1 chlb1_9_221.06 9 221.06 193.58−304.06 SRM_chr9_43503764 16.58 9.15E-05
      76 FC22 FC22_9.1_208.8 9 208.8 208.8−235.82 SRM_chr9_42299348 15.82 7.42E-08
      77 PGC_all PGC_all_9.2_211.37 9 211.37 208.8−253.02 SRM_chr9_42699215 33.79 2.07E-04
      78 UPGC_all UPGC_all_9.2_253.02 9 253.02 208.8−270.34 SRM_chr9_48970049 10.62 1.67E-04
      79 FC23 FC23_9.2_221.06 9 221.06 221.06−270.34 SRM_chr9_43503764 17.72 3.38E-05
      80 FC_all FC_all_9_246.13 9 246.13 226.53−306.74 SRM_chr9_48687085 24.41 6.15E-05
      81 PGC23 PGC23_9.2_235.82 9 235.82 235.82−254.7 SRM_chr9_46428172 16.76 1.07E-04
      82 UPGC23 UPGC23_9.2_254.7 9 254.7 235.82−270.34 SRM_chr9_49072035 14.97 9.97E-06
      83 FC21 FC21_9_307.28 9 307.28 246.13−311.19 SRM_chr9_54099646 9.49 4.87E-08
      84 FC22 FC22_9.2_280.75 9 280.75 263.41−298.3 SRM_chr9_51571090 31.14 1.09E-07
      85 PGC_all PGC_all_9.3_301.43 9 301.43 278.99−301.43 SRM_chr9_52368241 17.75 1.77E-05
      PGC = Percent green cover, UPGC = UAS-derived percentage green cover, FC = fall color, WI = winter injury, WK = winterkill, Antho = field anthocyanin rating, chla = chlorophyll a, chlb = chlorophyll b, caro = carotenoids, antho = lab-assayed anthocyanin, LG= Linkage group, cM = centimorgan, bp= base pair, %PVE= percentage phenotypic variance explained.
      Postpositive numbers/words 21, 22, 23, and _all on the trait column indicate years 2021, 2022, 2023, and across three years, whereas 1, 2, and 3 indicate sample collection dates September 21, September 28, and October 12, 2023, respectively.

      Table 2. 

      Significant quantitative trait loci associated with winter survival traits for the St. Augustinegrass Raleigh selfing population.

    • CHR RR QTL RS QTL Overlapping region (bp) Marker Drought QTL
      1 WK21_1_39.61, WI_all_1_39.61, WI21_1_39.61 RG4NCA-1 9390807−11566467 SRM_chr1_9390807*
      1 WI_all_1_39.61, WI21_1_39.61, Antho23_1_136.38 RG3CA-3 27814577−29079870 SRM_chr1_27814577
      SRM_chr1_27870581
      SRM_chr1_27961888
      SRM_chr1_27961961
      SRM_chr1_28009546
      SRM_chr1_28051626
      SRM_chr1_28611736
      SRM_chr1_28893001
      SRM_chr1_29079870
      2 WI_all_2.1_93.25, WI23_2.2_265.09 SGT4CA-1, RG3CA-1 33443012−33973299 SRM_chr2_33506472
      SRM_chr2_33943699
      3 FC_all_3_200.42, UPGC_all_3_151.83, WK21_3_153.75, UPGC23_3_153.75, PGC21_3_157.76, PGC_all_3_151.83, FC23_3_151.83, PGC23_3_219.58, PGC22_3_153.75 WK-2##, SGU-1##, SGU-1#, RG4CA-1 40124103−40305314 SRM_chr3_40124103 PR-3.1, PR-3.2, PGC-3.2, RWC-3.1
      SRM_chr3_40305314
      6 Antho23_6_99.16, PGC21_6_34.57, Antho1_6_86.51 SGT3NCA-1, SGT4-1, SGTNCA-2 4876694−5708895 SRM_chr6_4576937
      SRM_chr6_4839139
      SRM_chr6_4941052
      SRM_chr6_5034609
      SRM_chr6_5158405
      SRM_chr6_5597676
      SRM_chr6_5665068
      6 Antho23_6_99.16 RG3CA-2 23354478−25104204 SRM_chr6_23614612 LW-6.1
      SRM_chr6_24263583*
      SRM_chr6_24991566
      8 Antho23_8_210.16 RG3NCA-2 47044173−47121754 SRM_chr8_47044173
      9 PGC23_9.1_10.68, FC23_9.1_13.94, UPGC23_9.1_10.68, UPGC_all_9.1_10.68, FC21_9_28.57, PGC_all_9.1_10.68, PGC22_9.1_27.86, WI21_9_28.57 WK-1#, WK-1## 2522286−3275160 SRM_chr9_2522286*
      SRM_chr9_3008721
      SRM_chr9_3080260
      SRM_chr9_3275160* AULWC-9.1 at (2791593−3275160)
      CHR: Chromosome; * Peak markers associated with one or more QTL from the current study; #, ## denotes single year and across year QTL from Kimball et al.[13 ].

      Table 3. 

      Overlapping of winter survival QTL with previous studies in St. Augustinegrass. RR QTL was found in the Raleigh selfing mapping population. RS was the QTL found in the 'Raleigh' × 'Seville' bi-parental mapping population[13]. Drought QTL was found in the XSA10098 × XSA10127 bi-parental mapping population[43].