Abstract:

To adapt to dense planting of maize and meet the rapid mechanization development of agricultural production, the basic maize population was developed by using abroad excellent germplasm materials, then high-density and large-population selection, targeted inoculation and identification methods were adopted to obtain the new variety ‘Ruipu909’ with the disease-resistant self-line ‘RP86’ as female parent and ‘RP06’ as male parent. This variety has characteristics of density resistance, stress resistance, high yield and easy mechanical harvesting. The results show that the average yield of the regional test is 12589.5 kg/hm ², 7.1% higher than that of the control variety. There are 111 test points, the yield-increase points accounted for 93%. The yield of production test is 12601.5 kg/hm ², compared with the control variety, the yield increased by 7.7%, and there are 95% yield-increase points among the 54 test points. The average lodging rate in regional and production tests is 1.6%. ‘Ruipu909’ is resistant to northern corn leaf blight, stalk rot and ear rot. The crude starch content of seeds is 75.24%. In summary, the new variety ‘Ruipu909’ has multiple characteristics of high and stable yield, strong disease and lodging resistance, good quality, wide adaptability, density resistance and is suitable for mechanical harvesting. The variety was examined and approved by Shanxi Province in 2017 and was further approved by Shaanxi, Inner Mongolia and passed the national authorization in 2018. The variety is suitable for popularizing and planting in middle-late maturing areas of spring sowing regions in eastern north China and northwest China and Huanghuaihai summer maize areas in southern Shanxi.

Key words: maize variety, ‘Ruipu909’, density resistance, stress resistance, high yield, mechanical harvesting, selection and breeding