Revista Brasileira de Sementes
Print version ISSN 0101-3122
NEVES, Eletisanda das et al. Seed drying of corn ears as affected by layer depth and air flow. Rev. bras. sementes [online]. 2005, vol.27, n.2, pp.117-124. ISSN 0101-3122. http://dx.doi.org/10.1590/S0101-31222005000200017.
The objective of this study was to evaluate the stationary drying process of corn seeds on the ear at 30% moisture content dried in four perfurated floor prototypes with 0.92m diameter, 1.0m height and axial fan and internal tubes 2.00m high. Air flows of 5.15 and 20m3.min-1.t-1 were used with air heated to 30ºC providing RH from 40 to 70%. Evaluations were made after zero, six and 12 months of storage, determining seed moisture content during drying, proportion of internal breakage in seeds, standard germination, accelerating ageing, cold test without soil and field emergency. Results showed that stationary drying with 40 to 70% RH did not cause internally broken kernels of hybrid seed corn on the ear that were not affected even at the maximum air flow, nearest to the perfurated floor and to round seeds that are more susceptible to breakage. On the other hand, physiological quality was affected by air flows below 20m3.min-1.t-1, as detected by cold germination after one year of storage. Maximum drying rate must be 0.18%/hour with seed moisture above 25%; therefore, drying at 40 to 70% RH, the seed moisture gradient is 2%/hour up to 1.50m seed layer height at the end of drying. Average drying front speed is not directly affected by air flow.
Keywords : Zea mays; drying front; seed quality.