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  • Author or Editor: J. Johnson-Cicalese x
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Buffalograss [Buchloë dactyloides (Nutt.) Engelm] is a drought-resistant, dioecious species, native to the Central Great Plains, which shows excellent potential as a low-maintenance turfgrass. Although buffalograss can be propagated vegetatively, there is a need for seeded turf-type cultivars. To assist in developing seeded cultivars, heritabilities of turf characteristics were estimated. Heritabilities from maternal half-sib analyses ranged from h2 = 0.04 ± 0.03 for the 1988 uniformity rating to h2 = 0.62 ± 0.26 for the 1989 spring color rating. Heritability estimates calculated from offspring-parent regression were also variable and generally lower than maternal half-sib analysis. The results suggest that some turf characteristics are highly heritable and that growing conditions markedly affect heritability estimates.

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Fruit rot is the primary threat to cranberry (Vaccinium macrocarpon) production in the northeastern United States, and increasingly in other growing regions. Efficacy of chemical control is variable because the disease is caused by a complex of pathogenic fungi. In addition, cranberries are often grown in environmentally sensitive areas, placing restrictions on chemical control measures. Thus, a major focus of the cranberry breeding program is to develop cultivars with improved fruit rot resistance (FRR). Several genetically diverse sources of FRR have been identified in our germplasm collection. However, the most resistant accessions lack one or more attributes; e.g., productivity, required for commercial acceptance. These resistant accessions were used in crosses with elite high-yielding selections and in 2009, 1624 progeny from 50 crosses were planted in 2.3-m2 field plots. During 2011–13, under field conditions with very limited fungicide management, disease pressure was severe, allowing evaluation for FRR. Plots were rated on a 1–5 scale for incidence of fruit rot (where 1 = 0% to 20% rot and 5 = 81% to 100% rotted fruit), and rotted fruit counts were made from selected plots to validate the ratings. There was a good correlation in the ratings between years (2011 vs. 2012: r = 0.59, P < 0.0001; 2011 vs. 2013: r = 0.50, P < 0.0001; 2012 vs. 2013: r = 0.62, P < 0.0001), and between rot ratings and percent rotted fruit (r = 0.90, P < 0.0001). Significant differences were found between and within families for FRR. High heritability estimates (h 2 = 0.81) were obtained with midparent-offspring regression of mean fruit rot ratings, indicating additive genetic variance for FRR. Introgression of FRR into higher yielding genetic backgrounds was also accomplished, as some progeny exhibiting high FRR also had commercially viable yield (>300 g/0.09 m2), as well as good berry size and color. Selections are being further evaluated for potential cultivar release.

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