Abstract
The present study examined the effectiveness of powder humic acid (HA) as a source for enhancing growth and quality of maize fodder (Zea mays L.). The study was conducted at the Agriculture Research Station of King Abdul Aziz University, Saudi Arabia by growing maize 2 times during the crop season in the area spanning from September 2011-February 2012, using randomized block design. The effectiveness of HA was studied as controls (H-0: 0 kg of HA ha(-1)), and with 6 different levels of HA (H-1 = 5 kg of HA ha(-1); H-2 = 10 kg of HA ha(-1); H-3 = 15 kg of HA ha(-1); H-4 = 20 kg of HA ha(-1); H-5 = 25 kg of HA ha(-1); and H-6 = 30 kg of HA ha(-1)). Maize growth and quality parameters including plant height, number of leaves, leaf area, dry matter yield, minerals content, crude protein, and neutral detergent fiber (NDF) were measured 60 days after sowing (R1, Silks visibility stage) each time for the crop. Significant differences (p<0.05) were observed for all the mentioned parameters across the HA levels. Based on this study, application of H-4 (25 kg of HA ha(-1)) may be recommended to improve growth and quality of maize fodder in similar environmental conditions. Further research is required in diverse plant environments to determine economically feasible application level of HA while comparing it with other manures and organic fertilizer sources.