Determination of self-incompatibility and seed production rate in seeded type bermudagrass lines

Bermudagrass (Cynodon dactylon (L.) Pers) is the most widely used turfgrass species in parks, lawns, and sports fields in tropical and subtropical climates. Our country is located in the center of diversity for Bermudagrass. However, all the commercial seeded type Bermudagrass cultivars used in Turkey are currently imported, which increases establishment cost of green facilities. The aim of this study is to determine the selfing ratio and seed yield rates in selected breeding lines that can be used to develop seeded type Bermudagrass cultivars. Six tetraploid (2n=4x) breeding lines (C12, B3, A4, P-1, R-1, CLB-1) developed at Akdeniz University were used in this study. 15 different reciprocal crossing were made using the breeding lines. The study was conducted under field conditions with 3 replications. Flowering characteristics, self-incompatibility/selfing ratio and percent seed set ratio of the breeding lines were determined. The results revealed that the breeding lines showed significant variation in flowering characteristics, selfing and percent seed set ratios. Selfing ratio ranged from %0 to %0.4. Percent seed set ratio ranged from %1(CLB) to %30 (P1). The number of spikelets per spike (raceme) and per inflorescence varied from 18 (A4) to 25 (P-1) and 75 (CLB-1) to 100 (C12), respectively. The inflorescence density ranged from 2.6 (low) to 7.8 (high) using a scale of 1-9 among the breeding lines, and P-1 breeding line was determined to be the most prolific inflorescence producers all season long. The results revealed that the P-1 line, which has the highest general combining ability in terms of percent seed set with very dense inflorescence production ability per area, and yet has a very low (≤ 0.4%) selfing ratio, can be used as a parent in developing seeded type Bermudagrass cultivars. It has been determined that the P-1 line is quite compatible with especially C12 and B3 in terms of percent seed set ratio. Therefore P-1, C12 and B3 can be used for development of synthetic Bermudagrass cultivars with high seed yield.