INFLUENCE OF GATED PIPES IRRIGATION MANAGEMENT ON COTTON YIELD AND WATER EFFICIENCIES

Abstract

Field experiments were conducted at the experimental farm of Sakha and Edko Agricultural Research Stations, Kafr El-Sheikh and Al-Behera Governorates (31° 05’ N latitude and 30° 56’ E longitude) during 2011 summer season to study the effect of different land leveling methods and orifice flow rates on cotton yield for Giza 86 variety and some water relations under furrow irrigation using gated pipes in the salt affected soils. The treatments were arranged in a split – plot design with four replicates. The main plots were assigned to four land leveling methods namely: laser land leveling with zero, 0.05 and 0.1 % slopes in addition to traditional land leveling. Three orifice flow rates i. e. 1.5, 2.0 and 2.5 l/s were allocated in the sub- plots. The main results in this study can be summarized as follows: - 1- The laser land leveling method achieved the highest average values of water productivity (70.1 kg m-3 of water consumptive use), irrigation of water productivity (62.2 kg m-3 of water applied) and water application efficiency(95.2%) of cotton crop with 0.1% slope compared with the conventional land leveling method which recorded the lowest average values of WP(40.2 kg m-3 of water consumptive use), IWP(27.4 kg m-3 of water applied) and Ea(70.2%). This may be due to improvement of the soil moisture distribution in the root zone in case of the laser land leveling comparison with the conventional land leveling. 2- The data indicated that the highest amount of water applied( 4112 m3 fed.-1 )was recorded with the conventional land leveling method followed by laser land leveling at zero slope (3365 m3 fed.-1 ) while, the lowest amount of water applied( 2376 m3 fed.-1 ) was obtained the laser land leveling at 0.1% slope. 1 Cotton Res. Inst., Agric. Res. Center, Giza, Egypt 2Agric. Eng. Res. Ins., Agric. Res. Center, Giza, Egypt. 3- The furrow irrigation with gated pipes at 2.0 l/s orifice flow rate exhibited the highest average values of water productivity (60 and 59.5 kg m-3 of water consumptive use ), irrigation of water productivity (48 and 46.3 kg m-3 of water applied), water application efficiency(85.1 and 75.9 %) and seed cotton yield (1349 and 1432 kg fed.-1 ) compared with other orifice flow rates(1.5 and 2.5 l/s). This may be due to increasing in soil moisture content in the root zone and also leashing and removing the soil salts. 4- The highest values of seed cotton yield ( 1515and 1609 kg fed.-1 ), number of opened bolls per plant ( 16.9and 18.6 bolls plant -1 , boll mass (3.95 and 3.62 g ), lint percentage ( 40.8 and 39.3 % ), seed index ( 12.3 and 11.6 g), 2.5 span length ( 34.5 and 32.7 ), fiber strength (42.8 and 41.5 g tex -1 ) and plant height (115 and 105 cm ) were achieved with the laser land leveling method at 0.1 % slope and furrow irrigation regime using gated pipes at orifice flow rate of 2 l/s. 5- The interaction between land leveling and orifice flow rate of gated pipes had significant effect on seed cotton yield, its components and irrigation efficiencies under study. On the other hand, the highest values of seed cotton yield, seed index, boll mass, number of opened bolls and lint percentage were detected with the salt-affected soils(Edko region) because of increasing potassium and sodium cations ratio. 5- The laser land leveling at 0.1 % slope and furrow irrigation using gated pipes at 2.0 l/s orifice flow rate is recommended for irrigating cotton because it is very suitable in case of the old lands and that have salinization problems to obtain highest irrigation efficiencies and cotton yields.