A Single Dominant Gene Ch for Chilling Resistance in Cucumber Seedlings

An experiment was conducted to determine the genetics of chilling resistance in cucumber ( Cucumis sativus L.) inbred NC-76 that was developed from PI 246930, an accession from the U.S. Department of Agriculture germplasm collection. NC-76 was crossed with ‘Chipper’ and breeding line Gy 14 to produce F 1 , F 1 reciprocal, F 2 , and BC 1 generations for evaluation. Cucumber seedlings at the first true leaf stage were placed in growth chambers set at 4 °C for 7 h and a photosynthetic photon flux of 500 μmol·m −2 ·s −1 . Segregation in the F 2 fit a 3 : 1 inheritance pattern, with resistance being dominant. The backcross of the F 1 to the susceptible parent produced a 1 : 1 ratio, confirming that chilling resistance was from a single gene. The single dominant gene controlling chilling resistance in NC-76 was given the symbol Ch .