Assesment of irrigation water requirement of maize crop

Abstract

Water is one of the most important natural resources. The rationale use of this valuable resource is a dire need at present days because the useable water resource is diminishing very rapidly. Thousand of rivers are flowing through Bangladesh. The agriculture, transportation and economy of this country depends on these rivers. Irrigation for agriculture of this country mostly depends on surface and ground water. Bangladesh being a lower riparian country and the adverse effect of climate changes create less flow of these rivers. The less or no flow of these rivers resulting in shortage of irrigation water for agricultural production and these create a dire problem in agriculture sector for irrigation water in dry season of Bangladesh. A study was conducted during the dry season (Rabi) in 2010-11 at Bangladesh Agricultural Research Institute (BARI), Joydebpur, Gazipur, to assess the irrigation water requirement of maize crop and to observe the impact of tillage methods on water use and maize yield. The effect of irrigation water on maize yield and to measure the impact of tillage practices on the surrounding environment was the other observatory object of this project work. The interactive effects of irrigation and tillage on the maize yield and yield contributing parameters of BARI Hybrid maize-6 were observed. The determination of suitable water requirement for maize crop with effective tillage method for maize cultivation and the saving of valuable water resources were the prime concern of this project study. Significant impact of irrigation water on maize yield was observed. Under I1 irrigation treatment with zero (T1), minimum (T2) and traditional (T3) tillage practices, the seasonal water requirements were 28.30 cm, 31.30 cm and 33.00 cm respectively. In I2 irrigation treatment with zero, minimu and traditional tillage practices, the seasonal water requirements were 36.55 cm, 39.55 cm and 44.52 cm respectively and in I3 irrigation treatment with zero, minimum and traditional tillage practices, the seasonal water requirements were 48.30 cm, 53.30 cm and 62.00 cm respectively. Statistically no significant difference was found in I2 and I3 irrigation treatment for maize yield. In economical analysis, I3 irrigation treatment was not suitable because a huge amount of water was required in this treatment and net returns was low in comparison to I1 and I2 irrigation treatments. The highest benefit cost ratio (BCR), yield and net returns were found in T2I2 treatment. In three tillage treatments, the maximum yields were found in T2 (8.15 ton/ha) and T3 (8.2 ton/ha) tillage treatments and lowest was found in T1 (7.25 ton/ha) tillage treatment. The minor significant effects were found by differents tillage practices in yield and yield contributing characters of maize crop. From the economical analysis, the maximum net return was found in minimum tillage practices. Therefore, T2I2 treatment combination is preferable for maize cultivation because maximum water resources can be saved in this treatments without compromising with yield of maize in dry season (Rabi) of Bangladesh. T2I2 is the environment friendly treatment combination for maize cultivation because this treatment combination consumes minimum amount of fuel for tilling purposes and required less water resources for irrigation purposes and produces minimum amount of carbon dioxide (CO2) to the surrounding environment.