Efficiency in phosphate fertilizer application on garlic in marginal soil

English. The experiment was conducted at Marongan Village, Magelang, Central Java on andosol soil type (1,400 meter above sea level) in the rainy season 1993/1994. The objective of this experiment was to study the influence of soil liming and phosphate dosage on either the growth or yield of garlic. In fact, the results indicated that there was no interaction effect between the soil liming and phosphate dosage on both of the growth and yield of garlic. The soil liming of 1.5 t/ha of dolomite was able to stimulate the plant height, leaves number, and also increased the total fresh weight as well as the dry bulb weight. All the phosphate dosages gave significantly higher in plant height and leaves number than control, except at 20 days after planting. The more phosphate applied into the soil, the higher in both of the plant height and total fresh weight were achieved. The most efficient phosphate dosages on bulb yield (fresh and dried weight) and bulb diameter occured at a rate of 135 kg/ha P2O5. If this dosage is adopted by farmers, the use of phosphate fertilizer will be reduced by 55-77.5 percent

Indonesian. Penelitian ini dilaksanakan di Dusun Marongan, Jawa Tengah, pada tipe tanah Andosol (1.400 meter di atas permukaan laut) pada musim hujan 1993/1994. Penelitian ini bertujuan untuk mempelajari pengaruh pengapuran tanah dan dosis fosfat baik terhadap pertumbuhan maupun terhadap hasil bawang putih. Kenyataannya, hasil penelitian menunjukkan bahwa tidak terdapat pengaruh interaksi antara dosis kapur dan fosfat. Penambahan kapur 1,5 t/ha dolomit dapat meningkatkan tinggi tanaman, jumlah daun, dan bobot basah total serta berat umbi kering. Semua dosis fosfat dengan nyata memberikan pertumbuhan tinggi tanaman yang lebih baik, jumlah daun lebih banyak kecuali pada umur 20 hari setelah tanam. Semakin tinggi dosis penggunaan fosfat semakin tinggi pula tinggi tanaman yang diperoleh. Hasil yang sama juga diperoleh pada pengamatan bobot umbi total basah bawang putih. Dosis fosfat yang paling efisien terhadap hasil umbi (bobot basah dan bobot kering umbi) dan diameter umbi diperoleh dari perlakuan 135 kg/ha P2O5. Apabila dosis ini diadopsi oleh petani, maka penggunaan pupuk fosfat dapat dihemat sebesar 55-77,5 persen