Soil temperatures at different depths down the soil profile are important agro-meteorological indicators which are necessary for ecological modeling and precision agricultural activities.  In this paper, using time series of soil temperature (ST) measured at different depths (0, 5, 10, 20, and 40 cm) at agro-meteorological stations in northern China as reference data, ST was estimated from land surface temperature (LST) and normalized difference vegetation index (NDVI) derived from AQUA/TERRA MODIS data, and solar declination (Ds) in univariate and multivariate linear regression models.  Results showed that when daytime LST is used as predictor, the coefficient of determination (R2) values decrease from the 0 cm layer to the 40 cm layer.  Additionally, with the use of nighttime LST as predictor, the R2 values were relatively higher at 5, 10 and 15 cm depths than those at 0, 20 and 40 cm depths.  It is further observed that the multiple linear regression models for soil temperature estimation outperform the univariate linear regression models based on the root mean squared errors (RMSEs) and R2.  These results have demonstrated the potential of MODIS data in tandem with the Ds parameter for soil temperature estimation at the upper layers of the soil profile where plant roots grow in.  To the best of our knowledge, this is the first attempt at the synergistic use of

Mechanical threshing used when preparing maize seeds for planting subjects seed to damage and reduces seed quality.  The purpose of this study was to assess the effect of mechanical threshing on the quality of maize seed threshed at different moisture contents (MCs).  Seeds of dent maize JK968 and flint maize DD2 were threshed at 12, 15, 18, 21, and 24% MC.  The damage degree was determined by iodine staining, and seed vigor was assessed by standard germination (SG), cold test germination (CTG), accelerated aging germination (AAG), seedling emergence rate, and seedling root and shoot length.  The results showed that the damage percentage increased, and the seed vigor parameters decreased with increasing seed MC during threshing in both cultivars.  For obtaining high seed quality, indicated by at least 90, 85, and 80% of SG, AAG, and CTG, respectively, JK 968 and DD2 should be threshed at MC lower than 15 and 18%, respectively.  Furthermore, the damage mainly occurred in the apical part of seeds, irrespective of the threshing MC in both cultivars.  When the embryo was damaged, seedling emergence rates were significantly reduced with great influence on shoot length.  Damage to the endosperm resulted in little effect on seedling performance.  Flint maize DD2 was more tolerant to mechanical threshing than dent maize JK968.  These results provided technical reference for the production and processing of high vigor maize seeds.