南充地方甜橙丰产稳产,耐贮运是其特点;皮厚、种子多,采收时味酸,品质较差为其不足。推广良种锦橙,在南充地区虽能丰产优质,但品质远逊于江津,万县地区所产,竞争力不强,且其长期窖贮后,风味不及地方甜橙。因此,根据南充地区特点,选育地方甜橙良种,发挥窖贮优势,实为南充地区柑桔生产中的重要课题。1974年,四川省柑桔选种协作组的技术辅导组与当地同志一起,共同选出了青居6号,以后多次送省,地鉴定评选,被评为少核地方甜橙。1977年中国农科院柑桔所采穗繁殖,并进行多点试验;1978 Nanchong sweet orange rich and stable yield, storage and transportation is its characteristics; thick skin, more seeds, Pickling acid, poor quality for its lack. Jincheng promotion of high quality seeds in Nanchong area can yield high quality, but the quality is far inferior to Jiangjin, Wanxian area production, competitiveness is not strong, and its long-term pit storage, the flavor less than the local sweet orange. Therefore, according to the characteristics of Nanchong, breeding sweet orange varieties of local places, to play the advantages of pit storage, in fact, an important issue in the production of citrus in Nanchong. In 1974, the technical guidance group of Sichuan Citrus Selection Cooperative Group together with the local comrades jointly selected No. 6 Qingju and later sent the provincial and municipal appraisals for selection. The group was awarded the title of sweet orange with fewer nuclear places. In 1977, Chinese Academy of Agricultural Sciences, ear harvest citrus, and multi-point test;