Abstract

The experiment was applied in the autumn season (2021 AD) to study the growth and yield of corn, the American variety 6664 DKC for two different levels of irrigation determinants A1 every four days and A2 every eight days and groups of urea fertilizer B1 no addition and B2 addition (200 kg/ha) and B3 addition (400 kg/ha) e) and different levels of Biochar (eucalyptus wood) C1 add no and C2 add (7 tons/ha), C3 add (14 tons/ha), and C4 add (21 tons/ha) using the (RCBD) design and with three replicates. The results of the experiment showed significant differences between the determinants of irrigation and urea fertilizer and Biochar and the interaction between them and for all the studied traits. The levels A1, B3 and C3 were characterized by giving the highest average over the rest of the classes for the characteristics of plant height (229.74, 235.68 and 243.59) cm and leaf area index (5.00 5.48, 5.64), chlorophyll content (43.45, 47.78, 47.88) CCI, the weight of 500 grains (134.31, 136.21, 138.22) g, total grain yield (9.48, 10.18, 10.81) ton/ha, and total dry weight (18.83, 19.72 and 21.39) tons/ha, according to the order. The interaction of the combination A1B3C3 gave the highest average in plant height, leaf area index, and weight of 500 grains amounted to (258.40 cm), (6.50) and (142.12 g) according to the order, which did not differ significantly from A1B2C3, A2B2C3 and A2B3C3. As for the chlorophyll content, the combination A1B3C3 excelled with the highest rate of (55.14) CCI and did not differ significantly from A2B3C3, while the combination A1B2C3 characterized the character of the total yield by giving it the best rate of (12.12 tons/ha), and it did not differ significantly from A1B3C3 and A2B2C3 and A2B3C3. In contrast, in the dry weight character A2B3, the two combinations, A1B3C3 and A2B3C3, were characterized by giving the best weight (23.50 ton/ha), and they did not differ significantly from A1B2C3. We conclude from the study that treating the soil with 14 tons/ha of biochar increased the urea fertilizer to 50% and increased the limits of irrigation to 8 days, meaning that the application of (14 tons/ha) biochar + (200 kg/ha)
urea fertilizer and irrigation every eight days It was sufficient to meet the nutrient and moisture needs of the US 6664 DKC maize crop