The tolerance of early maize inbred lines to low soil temperatures in the seed’s germination phase

Abstract

Improving early maize for export to northern areas with reduced thermal conditions requires the identification of parental forms with tolerance to temperatures below the optimal biological threshold of 10-12 0C for seed germination. Each plot with dimensions of 5 m2 in two repetitions were planted with 100 untreated grains and distributed of 2 grains in 50 nests spaced at 14 cm. The sowing was performed at a depth of 5-6 cm at the end of March (30-31.03) and the next term over 15 days (14-15.04). Research has included as biological material 48 lines inbred in 2022 and 63 lines in 2023, representing the germplasm of the Euroflint heterotic groups with hardened grain and Iodent, BSSS-B37, Lancaster with dental grain. The experiences were placed in the permanent lot, isolated from the fields assigned to the research crop rotation, processed according to traditional corn technology. In the first decade of March 2022 the average temperature of constituted 8.0 0C compared to 5.6 0C in 2023. In the last decade, the average temperature has been 10.1 0C in 2022 and 9.6 0C in 2023. The appearance of the first seedlings in 2022 was reported after 29 days for the extra-early sowing period and 19 days for the next term.