Light and temperature indices during the seeding stage of spring maize in Hetao irrigation district, Inner Mongolia, China.

We collected the experimental dataset of a spring-maize in Hetao irrigation district (Bayannaoer, Inner Mongolia) during 2012 and 2013, as well as the crop data observed in related agrometeorological stations to investigate the impacts of light and temperature variation on maize development during the seedling stage to derive adequate light and temperature indices for different suitability. Furthermore, polynomial fitting was applied to interpolate the temperature indices for each day of the whole seedling period to draw the dynamics of the temperature indices and to better characterize its influence on maize development during the seedling stage. The results suggested that the emergence and development rates increased by 11% and 12%, respectively when the average temperature increased 1 °C during the sowing-emergence period and emergence-jointing period, and the biological lowest temperature was 7.4 and 11.9 °C, respectively. The optimum temperature at the sowing-emergence stage ranged from 16.0 to 18.0 °C, and the leaf area index at the three-leaf stage reached 0.0172 and above. The optimum temperature at the emergence-jointing stage ranged from 21.6 to 23.0 °C, and the photosynthesis/growth of plant tissue was positively correlated with the temperature. The leaf area index in the jointing period could reach 2.15 and the plant height was 120 cm. At the emergence-jointing stage, when the sunshine percentage ≥74%, or the daily sunshine hours ≥11.0 h • d-1, or the total sunshine hours ≥540 h, the dry mass of plant tissue could reach more than 34 g. [ABSTRACT FROM AUTHOR]