Background : The most problematic disease in Boxthorn is Anthracnose in open field. New variety with Anthracnose-resistant is good for high yield and Safe fruit production in open field. Therefore it is necessary to develop a new variety with Anthracnose -resistant and high yield.
Methods and Results : The new boxthorn line, CB10511-104 was selected from the cross between CB09480-18 and Chunghong (IT258916) to breed new variety with high yield, Anthracnose-resistant and good color in 2011. Its preliminary yield test was performed from 2013 to 2014 and the selected line was named Cheongyang 26. Its regional yield trials were carried out in Cheongyang, Yesan and Jindo for 3 years, from 2015 to 2017. Cheongyang 26 was registered as the new variety, Cheonggang, in 2017. The specific characteristics were summarized as follows. Tree shape is semi-open type and the leaf is lanceolate and green color. The flowers are normal size and purple. The fruit is normal size, round oval and redish. The flowering was June 17 with medium flowering. Number of sprout branch by pruning was generated less than the check variety, Cheongmeong. The infection rates on leaves to Eriophys macrodonis Keifer of Chunggang, 54.4 percent, was higher than the check variety, Cheongmeong. Anthracnose on fruits in open field was slightly strong compared to the check variety, but check variety was Anthracnose-resistant. The content of betaine and free sugar in dried-fruits were higher than that of the check variety. The dried-fruit yield was increased about 26 percent in open field compared Cheongmeong.
Conclusion : This variety ‘Cheonggang’ was suitable for cultivation in open field and rain-shelter plastic greenhouse because of Anthracnose-resistant and good color. It is necessary the companion variety because of self-incompatible. It’s suitable ‘Cheonggeum’ in open field, ‘Cheongun’ in rain-shelter plastic greenhouse.