| Summary: | Soil fertility evaluation is important in determining yield constrains and fertilizer efficiency. Thi research was conducted in 1998/1999 by analyzing Alfisols samples taken from groundnut production centers covering 9 and 6 districts in East and Central Java Provinces, respectively. In addition, a po experiment was also conducted to test the response of groundnut to N, P, K, and S fertilization. The objecav4 WaS to gel nutrient information in Alfisols in groundnut producing centers in East and Central Java, and al alternative of nutrient management to increase soil productivity. The results of the research showed that th4 majority of ,4Ifisols �om East Java had higher pH (varied from 7.0 to 8.4) than that from Central Javc (varied from 5.0 to 6.9). The variability of soil pH and Fe availability correlated significantly with th< groundnut productivity. The availability of Fe, Zn, Mn, and Cu in Alfisol from Central Java were high, Int the balance between Fe and the other ones, low soil pH, low available Ca and P might cause a log groundnut productivity. Phosphorus deficiency in Alfisol from East Java mainly took place in soil havin1 high soil pH and high exchangeable Ca. Nitrogen and phosphorus fertilization in the majority (60%) o thyland Alfisol from both area could increase groundnut productivity by over 50%.
Keywords.- nutrient availability, Alfisol, groundnut, soil fertility.
Evaluasi kesuburan tanah penting artinya untuk mengetahui kendala peningkatan produksi dar efisiensi pernupukan. Penelitian dilaksanakan pada MT 1998/1999 dengan melakukan analisis canto!, Canal Alfisol dart beberapa lokasi di sentra produksi kacang tanah yang meliputi 9 kabupaten di Jawa Timur clan [ kabupaten di Jawa Tengah. Di samping itu juga di]akukan percobaan pot, yang dibatasi hanya untuk menguj respon kacang tanah terhadap pemupukan N, P, K dan S. Tujuan penelitian adalah untuk mendapatkal infortnasi keharaan tanah Alfisol di sentra produksi kacang tanah di Jawa Timur dan Jawa Tengah, serf: alternative pengelolaan hara untuk meningkatkan produktivitasnya. Vasil pene]itian menunjukkan bahw mayoritas tanah Alfisol asal Jawa Timur tnempunyai pH lebih tinggi (7-8,4) dibandingkan Alfisol asal Jaw
|
|---|