INFLUENCE OF IRRIGATION WATER AMOUNTS AND NITROGEN RATES ON MAIZE PRODUCTIVITY AND SOME WATER RELATIONS IN WADI ELNATROON REGION,EGYPT

Abstract

Two field experiments were carried out at Wady Elnatroon, El-Behera governorate during 2008 and 2009 growing seasons to study the influence of irrigation water amounts and nitrogen fertilizer rates on maize yield and its components, and on some water relationships under drip irrigation method in the soil. The soil of the field experiments was sandy loam. The electrical conductivity of irrigation water was 1.1 dSm -1 . The treatments were arranged in a split plot design with four replicates. The main plots were assigned with four amounts of irrigation water of daily applied on a base of 100%, 90%, 80% and 70% of ETc with four nitrogen rates i.e. zero, 50, 100 and 150 kg N fed. -1 in the sub plots. The combined analysis over the two growing seasons showed that daily irrigation with applied water equals 100% of ETc increased plant height, ear length, number of grains row -1 , 100-grain weight and maize grain yield by 3.33, 7, 15.25, 6.19 and 37.25% as compared to daily irrigation with applied water equals 70% of ETc. Daily irrigation with applied water equals 100% of ETc, significantly increased N, P and K concentration in Zea maize plants and grains by (36.9, 21.2 and 9.8%) and (23.5, 21.2 and 18.5%) as compared to daily irrigation with applied water equals 70% of ETc, respectively. Increasing nitrogen rates up to 150 kg N fed. -1 significantly increased plant height by 5%, ear length by 5.9%, number of grains row -1 by 8.4%, 100-grain weight by 10.1% and maize grain yield by 47.25% as compared to the control treatment. Seasonal water use values were 52.93, 47.93, 42.8 and 38.68cm for irrigated plants with 100%, 90%, 80% and 70% of ETc, respectively. Daily irrigation with applied water equals 100% of ETc resulted in higher amount of irrigation water applied to be 59.5 cm, followed by daily irrigation with applied water equals 90%, 80%, and 70% of ETc to be 53.5 cm, 47.6 cm, and 41.6 cm, respectively. Daily irrigation with 90% of ETc resulted in the highest value of water productivity as compared to 100%, 80% and 70% of ETc. It could be concluded that for obtaining both high and good maize yield and facing the irrigation water shortage, daily irrigation with 90% of ETc must be added with 150 kg N fed -1 under the sand loam soil in Wady El-Natron region and in the same conditions.