Development of vegetative triploid turf-type bermudagrass [Cynodon dactylon × C. transvaalensis (C. × mangennisii Hurcombe)]

Hybrid bermudagrass (Cynodon dactylon (L.) Pers. × C. transvaalensis Burtt-Davy) is widely used for turf throughout subtropical and tropical climates because of its superior quality and performance. Development of cultivars adapted to broad range of environments is the main goal of many breeding programs. There is large variation for turfgrass characteristics and drought resistance among native bermudagrass (C. dactylon) germplasm originating from the Mediterranean region. Hence, the aim of this study was to develop triploid turf-type bermudagrass hybrids by making use of native genetic resources. Drought resistant tetraploid C. dactylon genotypes originating from the Mediterranean coastal region of Turkey were crossed with a diploid accession of C. transvaalensis from South Africa in 2011 and 2012. The hybrids were first identified using SRAP molecular markers. Then, phenotypic pre-selection was made for leaf shape, color and density and 273 hybrids were transplanted into the field. Two SSR markers further confirmed the true hybridity of 170 (62%) of these genotypes. Establishment rates in 2013, and turfgrass characteristics in 2014 and 2015 were recorded. Transgressive segregation was evident for estabilishment rate, turfgrass quality and color, and shoot density among progenies. Correlation analysis indicated that selection for shoot density, leaf texture, and prostrate growth habit could increase turf quality. The genotypes ‘45’ and ‘150’ were identified as promising parents for future breeding efforts as they provided positive general combining ability. The best ten hybrids with acceptable turfgrass characteristics were evaluated further under replicated field trials and line T4-C3 has just been released for commercial use.