Evaluation Of Drip Irrigation System On Coffee (Coffea Arabica): A Case Study Of Kilimanjaro Plantation In Moshi District Kilimanjaro Region Tanzania

ABSTRACT

This study was conducted at one of the estates in Kilimanjaro Plantation to assess the

performance of the drip irrigation system on coffee yield. Climatic, plant and soil factors

were used for the calculation of monthly crop water and irrigation requirements and results

compared with actual performance of the irrigation system. Further evaluation of the

system performance was carried out using catch cans. The experiment was carried out on a

3-year-old coffee cultivar N39 at 3m spacing between lines of plants and 1.5 m between

plants. The experiment was laid out in a randomized complete block design with five

treatments replicated four times. The treatments included five irrigation application

levels: T1, T2, T3, T4 and T5 corresponding to flow rates of 0, 0.6, 1.2, 1.8 and 2.4

lph/emitter respectively. The results from calculations showed that the daily irrigation

requirement is 18 litres per tree, or applying 90 litres at an irrigation interval of 5 days at

peak demand. The EU in the selected block was found to be 94%, which is within the

acceptable standards. The wetted area ranged from 0.12 to 0.21 m2. The relative water

supply ranged from 0.45 to 0.98 indicating that the crop demand was not met by both

rainfall and irrigation. Coffee yield and water productivity was also investigated. The best

treatment towards the yield of coffee was T5 which produced mean yield of 2945 kg/ha

while treatment T1 produced the least yield of 2045 kg/ha. The best WP was 1.56 kg/m3

found in T1 and lowest was 0.95 kg.m3 in T5. There were significant differences in yield

and irrigation water productivity between treatments. T1 and T2 were not significantly

different. It is recommended that further research covering other parts of the plantation

should be conducted to confirm the results from this study.