Effects of Meteorological Factors at Different Growth Stages on Yield Traits of Maize ( Zea mays L.) in Heilonggang Basin

Abstract

Sowing date affects the phenology of crop through adjusting meteorological factors at different growth stages, which plays an important role on development and yield in maize. A two-year field experiment was conducted to assess the effects of meteorological factors on summer maize yield and its components under various sowing dates in Heilonggang basin in 2009 and 2010. Zhengdan 958 (ZD958), a popular cultivar in the region, was sown at five sowing dates (20 April, 5 May, 20 May, 4 June, and 18 June) in 2009 and three sowing dates (30 April, 21 May, and 11 June) in 2010, respectively, and harvested at physiological maturity (R6) stage. Meteorological factors, including maximum temperature, minimum temperature, temperature range, growing-degree day, precipitation, wind speed, maximum wind speed, relative humidity and sunshine duration, maize yield and yield components including ear number (EN), kernel number per ear (KNE) and 1000-kernel weight (KW), as well as the relationship between meteorological factors and yield components were analyzed. Partial correlation analysis was used to estimate the effect of agro-meteorological variables on maize yield. The results showed that due to the annual difference of meteorological conditions, yield traits were not changed with sowing date. At the density of 8.25 plants ha?1, multiple linear regressions between yield and its components suggested that a high KW combined with a stable KNE was important to increase yield. Yield traits were closely correlated with various meteorological factors at different growth stages. The light condition affected KNE and yield significantly during ear formation stage and anthesis stage. Daily temperature range was significantly correlated with yield at seedling and vegetative growth stage. Daily maximum temperature and daily minimum temperature significantly affected KNE from tasseling to silking. Effective precipitation of whole growth period influenced the increment of KW and KNE. The above factors are important in sowing period adjustment and choosing cultivation methods. Therefore, a technique could be applied in this area with earlier sowing date and delayed harvest, so that stress from adverse weather conditions could be avoided and kernel filling duration could be extended to achieve maximum yield.