Maize growth and yield response to different rates of humic acid and zinc

Abstract EN

To study humic acid and zinc effect on maize (Zea mays L.

) growth, yield and its attributes, a field experiment was set up during 2021 summer season in a Private Farm at Al-Maamorah district, El-Ghafara, Tripoli, Lybia.

Randomized complete block design with split-arrangement in three replicates was used.

Four humic acid levels, i.

e.

control (without humic acid), 5, 10 and 15 kg/ ha were randomly distributed as main plots, while four zinc concentrations (0, 3, 6 and 9 ml/ l) were allocated in the sub-plots.

Pioneer 3084 maize plants treated with humic acid significantly surpassed, in all growth, yield, yield components and grain protein content traits, than the control treatment.

The same trend was found for zinc foliar application, except for ear length.

Soil application of 15 kg humic acid per hectare combined with 9 ml zinc/ l as foliar application produced the highest values for ear leaf area (1000.17 cm²), plant height (240.56 cm), stem and ear diameters (2.20 cm and 4.52 cm, respectively), tallest ears (25.19 cm), number of rows/ ear (14.62), number of kernels/ row (54.13), shelling percentage (82.17 % ), 100-kernel weight (41.83 g), grain yield (7.192 t/ ha) and grain protein content (10.17 % ).