RESEARCH REPORTS 2018 Philipp W. Simon Carrot Breeding to Develop and Introduce Improved Cultivars for California Producers Philip A. Roberts Identification of Gene Sources for Resistance to Root-knot Nematodes Attacking Carrots in California Jeremiah Dung Evaluation of Quaternary Ammonium Chloride Products for Bacterial Blight Control Mary Ruth McDonald Evaluation of Carrot Breeding Lines for Susceptibility to Cavity Spot