The application of water pump for food crops grown on dry land and rainfed lowland condition

English. Most of secondary crops in Indonesia are grown on dry land and rainfed lowland condition. Under dry land condition maize, peanut and soybean are planted in early wet season; and late wet season under rainfed lowland in order to make use of available moisture. However, insufficient rainfall often occurs during the growing season of the crops. Application of water pump is necessary to provide enough moisture for plants, particularly in intensification program of production system. Appropriate use of water pump is determined by its type and engine, discharge capacity, irrigation method, and crops. Several types of water pump have been developed by RIMC (previously, MORIF). This paper describes and reviews some technical specification of water pumps and irrigation method for maize, soybean, and peanut. Financial analysis of the water pump application is presented. A modified axial pump, 8 inches in diameter (PS-3), used under riverbank of less than 30 deg. in slope, suction lift of less than 4 m has discharge less than capacity of 134.1 cubic meter/h. Provided that water requirement for maize, peanut, and soybean were 420, 351, 271 mm/ha/season, respectively, application of the water pump would be able to irrigate 26.4 ha, 31.6 ha, and 40.9 ha of maize, peanut, and soybean crops, respectively. Effective use of the water pump in maize is attairable when 50 percent ETA of water requirement is supplied during the first four weeks after planting then all (100 percent ETA) of the water need should be supplied for the later stages of the crop. In peanut effective application is achievable when water is pumped every 14 days (70 mm/ha/season) during vegetative stage followed by more frequent every 7 days (35 mm/ha/season) pumping during generative stage. In soybean, application of water pump is recommended every 14 days beginning post emergence up to maturity stages. All of the mentioned practice water distribution apply furrow irrigation method. The result of the financial analysis for water pump rental business showed B/C ratio 2.06; IRR 106.55 percent and BEP 5.60 ha/season/year

unknown. Sebagian besar produksi tanaman pangan (palawija) di Indonesia pada lahan kering dan sawah tadah hujan. Pada umumnya, tanaman jagung, kacang tanah dan kedelai tumbuh pada awal musim hujan di lahan kering dan akhir musim hujan pada sawah tadah hujan. Selama satu tahun pertanaman, palawija mengalami keterbatasan ketersediaan lengas tanah. Intensifikasi pertanaman palawija pada lahan kering dan sawah tadah hujan perlu penggunaan pompa air. Penggunaan pompa air ditentukan antara lain: tipe pompa dan enjin, kapasitas pemompaan, cara pemberian air dan jenis tanaman. Beberapa tipe pompa air telah dikembangkan oleh Balittan atau Balitjas. Makalah ini menyajikan spesifikasi pompa air, cara pemberian air pada tanaman jagung, kedelai dan kacang tanah dan analisis finansial. Modifikasi pompa aksial (pompa sepak) ukuran diameter 8 (PS-3) inchi pada kondisi tebing sungai kurang dari 30 derajat, daya capai kurang dari 4 m, dan mempunyai kapasitas pemompaan 134,1 meter kubik/jam. Pemberian air dengan pompa ini (420 mm/ha/musim, jagung); (351 mm/ha/musim, kacang tanah); (271 mm/ha/musim, kedelai) adalah cukup untuk mengairi seluas 26,40 ha tanaman jagung; 31,58 ha tanaman kacang tanah; dan 40,93 ha tanaman kedelai. Kinerja pompa ini menjadi baik dan dapat meningkatkan hasil dan berat berangkasan pada saat pemberian air 50 persen ETA mulai perkecambahan sampai dengan pemantapan tumbuh untuk tanaman jagung setiap 14 hari sekali (70 mm/ha/musim) pada fase vegetatif kemudian 7 hari sekali (35 mm/ha/musim) pada fase generatif untuk tanaman kacang tanah, setiap 14 hari sekali pada saat fase perkecambahan sampai dengan menjelang panen untuk tanaman kedelai. Metode pemberian air umumnya adalah alur terbuka. Analisis finansial untuk pemilik pompa air menunjukkan bahwa B/C ratio 2,06, IRR 106,55 persen dan BEP 5,60 ha/musim/tahun