Breeding and High Yield Seed Production Technology of High Quality New Maize Variety Longdan 246

In order to promote the demonstration and popularization of Longdan 246 in suitable planting areas, the breeding process, related characteristics, yield, supporting cultivation and seed production techniques of Longdan 246 were introduced in this paper. Longdan 246 was bred by the High Yield Genetics and Breeding Research Office of Maize Research Institute of Heilongjiang Academy of Agricultural Sciences in 2015 with improve inbred line H286 as female parent and improve inbred line LX461 as male parent. The variety was approved by Heilongjiang Crop Variety Approval Committee in 2023（Approval Number: Heishenyu2023L0044）.Participated in the regional trial of Heilongjiang Longke Maize Science and Enterprise Joint Venture from 2020 to 2021, with an average yield of 9 901.2 kg · ha^-1, an average increase of 9.0% compared to the control varieties Hetian 4 or Dongnong 254; In 2022, participated in the production experiment of Heilongjiang Longke Maize Science and Enterprise Joint Venture, with an average yield of 10 752.3 kg · ha^-1, an average increase of 7.0% compared to the control Dongnong 254.It has the characteristics of high quality, multi resistance, high and stable yield and so on.