培育高产、稳产籽粒直收玉米品种是玉米产业机械化发展的基本保障。为解决甘肃近年来玉米产业发展中存在的农业劳动力紧缺、玉米生产机械化程度低、宜机械收获籽粒品种缺少等问题，甘肃省农业科学院作物研究所玉米遗传育种团队通过种质资源改良、双单倍体诱导加倍、多环境胁迫选育、多生态区联合鉴定等技术，以自育自交系Z39-1为母本、DH系DHZ62-53为父本选育出了高产高抗宜机收玉米新品种陇单639。在2020 — 2021年进行的甘肃省玉米机收组区域试验中，陇单639 2 a 10点(次)收获时籽粒平均水分含量为237.5 g/kg，平均破损率为4.0%，平均折合产量为16 095.0 kg/hm2，较对照品种先玉335增产5.9%。在2022年进行的甘肃省玉米机收组生产试验中，5试点平均籽粒水分含量为209.0 g/kg，籽粒破损率为4.0%，平均折合产量为 15 012.0 kg/hm2，较对照品种先玉335增产6.4%。陇单639生育期平均为140 d，株型半紧凑，株高290 cm，筒型果穗，半马齿型籽粒，穗长19.6 cm，穗行数16行，穗轴红色，籽粒黄色，千粒重419 g左右。高抗禾谷镰孢茎腐病，中抗丝黑穗病、大斑病，感禾谷镰孢穗腐病。陇单639籽粒含粗蛋白为87.10 g/kg、粗脂肪为369.0 g/kg、粗淀粉为766.70 g/kg、赖氨酸为2.97 g/kg，容重为728 g/L。同时该品种表现出高产、稳产、抗倒伏、脱水快等特点，在成熟后田间可站秆20 d以上，具备机械收获籽粒品种的主要特征。适宜在甘肃省中晚熟春玉米类型区机收种植。

Cultivating high-yield and stable grain varieties for direct harvesting is the basic guarantee for the mechanization development of maize industry. To address the issues of labor shortages, low mechanization levels in maize production, and a lack of varieties suitable for mechanical grain harvesting in Gansu in recent years, the maize genetics and breeding team from the Crop Research Institute of the Gansu Academy of Agricultural Sciences bred the new high-yield, highly resistant, mechanically harvestable maize variety Longdan 639. The breeding process involved germplasm resource improvement, doubled haploid (DH) induction, selection under multi-environment stress, and joint identification across multiple ecological zones. It was developed using theself-bred inbred line Z39-1 as the female parent and DH line DHZ62-53 as the male parent. In the 2020 to 2021 Gansu maize mechanized harvesting regional experiment, Longdan 639 had an average grain moisture content of 237.5 g/kg and an average damage rate of 4.0% across 10 harvest points. The average yield was 16 095.0 kg/ha, which represented a 5.9% increase compared to the control variety Xianyu 335. In the 2022 Gansu maize mechanized harvesting production experiment, the grain moisture content averaged at 209.0 g/kg, with a damage rate of 4.0%. The average yield was 15 012.0 kg/ha, an increase of 6.4% compared to Xianyu 335. Longdan 639 has an average growth period of 140 days, with a semi-compact plant type and a plant height of 290 cm. It has a cylindrical ear, semi-dent grain, an ear length of 19.6 cm, 16 kernel rows, a red cob, and yellow kernels, with a 1000-kernel weight of 419 g. The variety exhibits high resistance to Fusarium stalk rot, moderate resistance to head smut and northern corn leaf blight, and susceptibility to Fusarium ear rot. The grain of Longdan 639 contains 87.10 g/kg of crude protein, 369.0 g/kg of ether extract, 766.70 g/kg of crude starch, and 2.97 g/kg of lysine, with a bulk density of 728 g/L. The variety also shows characteristics of high yield, stable yield, lodging resistance, and fast dehydration. After maturation, it can remain standing in the field for more than 20 days, exhibiting key traits for mechanical grain harvesting. It is suitable for machine harvesting in the mid- to late-maturing spring maize regions of Gansu Province.

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国家自然科学基金(32360511、32160490)；甘肃省农业科学院生物育种专项(2024GAAS24)；甘肃省农业科学院科技成果转化项目(2024GAAS-CGZH03)。