APPLICATION TIME AND RATE IMPACT OF POULTRY LITTER AND UREA ON CORN GRAIN YIELD IN ALABAMA
Singh, R1; McGriff, E.2; Prasad, R.31Graduate Student, Auburn University, Auburn University, AL, 36849
2Regional Extension Agent, Alabama Cooperative Extension System, Cullman County Extension Office, AL, 35055
3Assistant Professor and Extension Specialist, Auburn University, AUBURN, AL, 36849
Abstract:
In Alabama, poultry is a major industry having a total economic impact of $15.1 billion and generating an estimated 1.4 billion kg of poultry litter (PL). PL is regarded as a relatively cheap source of nutrients particularly N and P for row crops especially corn (Zea mays L.). However, there is little information regarding yield benefits with respect to PL application rate and time contrary to urea-based fertilization. The study compared the application rate and time effects of urea and PL on corn grain yield. The research was conducted at two sites (E.V Smith and Wiregrass) in a randomized complete block design with four replications. The treatments included two N sources applied at two rates i.e. 168 (low) and 336 (high) kg N/ha for urea and a similar N equivalent of PL (5.60 and 11.20 Mg/ha); two application times (single application at planting and split application as 25 % N at planting + 75% N at V6) and two urea and PL combinations each with low and high rate. The corn yields were standardized to 15.5 % moisture and 56 pounds per bushel. The results indicated that there was a significant effect of treatment (P<0.0001) and location (P<0.0001) on grain yield, however, the interaction effect of treatment and location was also significant (P<0.0001). A significant N source × location interaction effect (P<0.0001) and N rate × location interaction effect (P = 0.0003) on grain yield was observed. There was no significant difference between single and split applications of both PL and urea (P > 0.05).