冀单四号也叫廊研一号,是1973年廊坊地区农科所用自330作母本,广525作父本选育成功的单交种。当时制定的育种目标是:选育适合我区麦田套种的,抗大、小斑病,前期抗旱,后期耐涝,高产稳产的中熟玉米杂交种。1972年开始搞杂交,曾以兰289、金57、埃及205、维尔118等自交系,组配了一批杂交组合,由于抗病性不强,没有筛选出来。1973年选 Jidan IV, also known as Langyan 1, was used in 1973 in Langfang Agricultural Science since 330 for the mother, widely 525 for the successful breeding of single cross-species. Breeding objectives formulated at that time are: Breeding suitable for intercropping wheat fields in our region, resistant to large and small spot disease, drought, waterlogging late, high and stable yield of medium-maturity corn hybrids. In 1972, he began to engage in crossbreeding. He used a number of inbred lines such as Lan 289, Jin 57, Egypt 205 and Weier 118 to form a crossbreeding line. Because of its low disease resistance, it was not screened out. 1973 election