الري بالتنقيط السطحي و تحت السطحي و أثرها في صفات نمو و نوعية الذرة الصفراء

الملخص EN

This research was conducted to study the effect of surface (DI) and subsurface drip irrigation (SDI) on growth characters and seeds component qualities of Corn var.

Bohoth 5018.

The experiment was carried out at the farm of field crops Department, College of Agriculture, University of Baghdad, Abu Graib, during the spring season of 2013.

A randomized complete block design (RCBD) was used with split plot arrangement of three replications.

System Operational Pressure (P) of three levels ( 30, 50 and 70 kpa) were used as main plots, referred to as p1 , p2 and p3 respectively, and Irrigation methods (DI and SDI) as subplots.

Data showed that using SDI resulted in increased soil volumetric moisture content which leads to increment in plant high by 4.13%, plant leaves area by 1.22%, total dry matter weight by 9.60%, and crop growth rate (CGR) by 9.62% comparing with DI.

Increasing the system operational pressure (P) from 30 to 70 Kpa resulted in increasing plant high, plant leaf area, total dry weight, and CGR by 19.01, 22.57, 28.35, and 28.35% respectively.

None of the treatments have an effect on corn grains oil and protein content.

While system operational pressure (P) increment caused a significant reduction in grains carbohydrates content by 10.26%.

Irrigation method have no effect on grains carbohydrates content.

Development in growth characters end up with improving corn yield by 2.3% under subsurface irrigation and by 6.5% under higher system pressure (70 Kpa).

Growth characters were significantly and positively correlated with most of yield and quantitative characters with correlation coefficient (r) value rated between 1.00 to 0.85, while qualitative characters were not constantly correlated with quantitative, as correlation of protein percentage in grains was significantly positively correlated with number of grains per row (r = 0.91) and number of rows per ear (r = 0.88).

While carbohydrate and oil percentages were not significantly correlated with quantitative characters and other growth characters.

It can be concluded that the use of subsurface drip irrigation system under 70 Kpa water pressure located under 0.20m deep, achieved an improvement in corn growth characters, but has no effect on oil and protein percentage.

Growth characters were significantly and positively correlated with yield and quantitative characters of corn crop.