“楚门文旦”是我国柚类优良品种,已有120年栽培历史,1986年玉环全县文旦种植面积忆达2.6万亩,由于存在较严重的裂果问题,给生产者构成经济损失。1983、1984两年全县文旦产量2万多担,而每年裂果率达20％以上。其中解放圹农场四大队(海涂)文旦园的年裂果率占总产量的35％以上。玉环县在“七·五”末文旦结果面积达1.5万亩,年产量可达30万担,而年裂果的经济损失将达50余万元。为此,对文旦裂果及其防治开展综合研究很有必要。本研究从不同砧木,不同果实类型、不同时期的施肥标准、挂果量、立地条件等五个方面探索引起文旦 “Chumen pomegranate” is a fine variety of pomelo in China, which has been cultivated for 120 years. In 1986, the area planted with pomelo in Yuhuan County was 2.6 million mu. As a result of the serious cracking problem, economic losses were caused to producers. In 1983 and 1984, the county produced more than 20,000 dandelions, while the annual fruit cracking rate reached more than 20%. Among them, the liberation farm farm four brigade (sea Tu) Pandan Park annual cracking rate of more than 35% of total output. Yuhuan County at the end of the “Seventh Five-Year Plan” results in an area of ​​15,000 mu, the annual output of up to 300,000 Tam, while the economic losses of the annual crack will reach 500,000 yuan. Therefore, it is necessary to carry out a comprehensive study on the occurrence and prevention of Wendeng fruit. In this study, from different rootstocks, different fruit types, different periods of fertilization standards, fruiting quantity, site conditions and other aspects to explore the cause