Water use, growth, and yield of drip irrigated cassava in a humid tropical environment

Abstract

Field experiments were conducted at the Agricultural Engineering Experimental Farm of The Federal University of Technology, Akure, during 2006/2007 and 2007/2008 seasons to investigate the response of cassava under drip irrigation. The experiment was laid out in a randomised complete block design (RCBD) with three replications. The treatments were based on four different water regimes; with T100 receiving 100% available water (AW), T<sub>50</sub> and T<sub>25</sub> receiving 50% and 25% of AW and T<sub>0</sub> with zero irrigation (control treatment). Disease free stems of the cassava cultivar TMS 91934 were planted at a spacing of 1 m by 1 m. The results indicated that T<sub>100</sub> full treatment produced the highest average total dry matter yield of 49.12 and 37.62 t/ha in 2006/07 and 2007/08 cropping seasons, respectively. However, the average total dry matter production in T<sub>50</sub>, T<sub>25</sub>, and T<sub>0</sub> showed significant differences in their values. Low total dry matter yields of 7.12 and 5.92 t/ha, respectively, were associated with T<sub>0</sub> for the two cropping seasons. The total water use of 1491.75 and 1701.13 mm was recorded for T<sub>100</sub>, while total water use of 729.00 and 651.13 mm were obtained for T<sub>0</sub> in the two cropping seasons. The water use efficiency determined for the two cropping seasons ranged between 7.38 kg/ha and 32.93 kg/ha. The percentages of total water applied from total water use for T<sub>100</sub> were 51.11% and 61.72%, while 14.83% and 17.85% were recorded for T<sub>25 </sub>for 2006/07 and 2007/08 cropping seasons, respectively.