Assessment for increasing productivity of suboptimal land with using three kinds of organic fertilizer and six rice varieties had been conducted in the Debowae village, Waeapo district, Buru regency at 2011.  Purpose of the assessment were to determine the effect of three types organic fertilizer and the use of six Inpara varieties to growth and productivity of rice in sub-optimal land. Study used a split plot design with three replications (farmers as replicates), where the main plot was three types of organic fertilizers (livestock manure, granular organic, and petroganic), while the subplot was 6 varieties Inpara (Inpara 1, Inpara 2, Inpara 3, Inpara 4, Inpara 5, and Indragiri). The soil types at the study site based on soil classification were Endoaquepts with soil fertility status was low. The study results  showed  that  the use of organic  manure combined with inorganic fertilizers,  both  from  livestock manure, while granular organic and petrogranic, gave an average crop growth and yield better than the results obtained by farmers outside of the study. Average petroganic fertilizer had a better growth and higher crop yields compared to other organic fertilizers. The six varieties of rice swamps that were examined (Inpara 1, Inpara 2, Inpara 3, Inpara 4, Inpara 5, and Indragiri) had the average growth and better yields than rice varieties used by farmers outside of the study (2.75 t ha-1). Varieties Inpara 4, Indragiri, Inpara 1 and  Inpara 2 had average yield above 7 t ha-1, while Inpara 3 and  Inpara 5 average above 4 t ha-1. Combination of granular organic fertilizer with Inpara 4 variety and petroganic with Indragiri variety had the best results (8.37 and 8.02 t ha-1), while the lowest yield (4.48 t ha-1) was reached at combination of  livestock manure with Inpara 5 variety.Keywords: adaptive varieties, land and plant management, organic fertilizers, suboptimal land [How to Cite: Marthen PS and MLJ Titahena. 2014. Improvement of Suboptimal Land Productivity Approach by Land and Plant Management. J Trop Soils 19(2): 109-119. Doi: 10.5400/jts.2014.19.2.109]

Research was conducted in Gowa, South Sulawesi at dry land farmer during two years. The aims of the research was to get the best method in ascertainment of availability class of potassium (K) for maize in dry land. The research used a single location approach, which made some of K nutrient artificial. Result of this research indicated that K nutrients class which reached by several methods are: (1) by Cate-Nelson method : two class, ie low and high class, (2) by curve continue method: two until three classes, ie very low to moderate class, low and moderate, and low to high class; and (3) by analysis of variance modified method: three classes, ie low to high class. Ascertainment of K nutrient availability classes by modified analysis of variance method was the best methods compared to other methods. Critical level of K nutrient for maize according to modified analysis of variance method by several extractant is: 0.40 me K 100 g-1 for NH4OAc pH 4.8 extractant; 0.40 to 0.60 me K 100 g-1 for NH4OAc pH 7 extractant; 200-300 ppm K2O for Bray-1 extractant, and 215-250 ppm K2O for Olsen extractant. [How to Cite: Marthen PS and P Tandisau. 2015. Ascertainment of K Nutrient Availability Class for Maize by Several Methods. J Trop Soils 19: 21-27. Doi: 10.5400/jts.2015.20.1.21][Permalink/DOI: www.dx.doi.org/10.5400/jts.2015.20.1.21]

ABSTRAKThe study was conducted in Selaru Island, West Southeast Moluccas Regency in an area of 32,217 ha. The research objective was to determine the land suitability and proposed land utilization of Selaru Island for development of food crops. The results showed that Selaru Island has a rather suitable (S2) and marginally suitable (S3) for six crops (upland rice, corn, peanuts, mungbeans, sweet potato, and caladium) covering an area of 19,330 ha and not suitable permanent (N2) for the six crops covering an area of 3,905 ha, while the area of 8,982 ha partly classified accordingly (S3) to plant upland rice and calladium and partially classified as not suitable (N1 and N2) for corn, peanuts, mungbeans, and sweet potatoes. The main limiting factor to the primary land use for food crops in Selaru Island, West Southeast Moluccas Regency among others are the temperatures (the average annual temperature is high), rooting medium (soil solum is shallow), nutrient retention (soil pH is rather alkaline to alkaline), erosion hazard level is moderate, and terrain (wave, rocks on the surface of the soil, and rock outcrop).The proposed land utilization of Selaru Island for food crops based on land suitability classes are (1) food crops of upland-1 with the main commodities of corn, mungbeans, uwi/kumbili and caladium an area of 5,299 ha, (2) food crops of upland-2 with the main commodities of upland rice, uwi/kumbili and caladium an area of 8,982 ha, and (3) food crops of upland-3 with the main commodities peanuts and mungbean an area of 14,031 ha. Development of food crops in Selaru Island need to consider the priority scale factor, the level of compliance, and social culture of the local community.Keywords: Food crops, land suitability, limiting factor, proposed land utilization, Selaru Island Penelitian dilakukan di Pulau Selaru, kabupaten Maluku Tenggasra Barat pada areal seluas 32.217 ha. Tujuan penelitian adalah untuk mengetahui kelas kesesuaian lahan dan arahan penggunaan lahan Pulau Selaru untuk pengembangan tanaman pangan. Hasil penelitian menunjukkan bahwa Pulau Selaru memiliki lahan yang agak sesuai (S2) dan sesuai marginal (S3) untuk enam jenis tanaman pangan (padi gogo, jagung, kacang tanah, kacang hijau, ubi jalar, dan keladi) seluas 19.330 ha dan yang tidak sesuai permanen (N2) untuk keenam jenis tanaman pangan seluas 3.905 ha, sedangkan lahan seluas 8.982 ha sebagian tergolong sesuai (S3) untuk tanaman padi gogo dan keladi dan sebagian tergolong tidak sesuai (N1 dan N2) untuk tanaman jagung, kacang tanah, kacang hijau, dan ubi jalar. Faktor pembatas utama penggunaan lahan Pulau Selaru, Maluku Tenggara Barat ntuk tanaman pangan antara lain adalah temperatur tinggi, media perakaran (solum tanah dangkal), retensi hara (pH tanah agak alkalis sampai alkalis), tingkat bahaya erosi sedang, dan terrain (berombak, batuan pada permukaan tanah dan singkapan batuan). Arahan penggunaan lahan Pulau Selaru untuk tanaman pangan berdasarkan kelas kesesuaian lahan adalah (1) tanaman pangan lahan kering-1 dengan komodit...

Rate of fertilizer that should be applied to rice soil based on Site Specific Nutrient Management (SSNM) depends on indigenous nutrient supply, its recovery efficiency, and the amount of nutrients requirement to achieve the yield target. Research on nutrient omission plot was conducted in farmers irrigated land on Waeapo plain, Buru Island. In this area, N, P, and K were the main limiting factors of rice growth and yield. To overcome the constraint, this assessment was conducted to determine the indigenous supply of N, P and K and optimal target of rice productivity. Results of this assessment showed that  the average of rice optimum productivity (Mg grain water content/w.c. 14% ha-1)  in Waeapo plain was 6.55 Mg DGM (Dry Grain Milled) ha-1, with range from 5.6 to 7.3 Mg DGM ha-1 depended on the indigenous supply of  N, P and K. The average value of the indigenous N, P and K supplies in Waeapo plain  Buru was 65.59 kg N ha-1, 13.70 kg P ha-1 and 78.65 kg K ha-1, respectively while average productivity of rice on that indigenous N, P and K supplies was 5.05, 5.96 and 6.05Mg DGM ha-1, respectively. The value of indigenous nutrient supply of this nutrient can be used as a basis of fertilizer recommendation with the SSNM concept. Keywords: Indigenous nutrient supply; nitrogen; phosphorus; potassium; Site Specific Nutrient Management [How to Cite: Andriko NS and  MP Sirappa. 2014. Assessment of Indigenous N, P and K Supply for Rice Site Specific Nutrient Management in Buru Regency. J Trop Soils 19: 151-159. Doi: 10.5400/jts.2014.19.3.151]

The objective of the study was to determine the potency of dairy cattle development, famers income, factors influencing the income of dairy farmers in the West Ungaran District. This study was conducted from February to April 2016. The determination of the sample villages was using purposive based Livestock Farmer Group (LFG) and the total population of dairy cattle. Further, respondents were determined by using census method for 47 people; those were 13 respondents of “Mardi Mulyo” LFG members, 7 respondents of “Sumber Hasil” LFG members, and 27 respondents of “Ngudi Makmur” LFG members. This study used regression, and SWOT analysis. The results of this study showed the multiple regression analysis showed that milk production significantly influences the income of dairy farmers. Farmers income in “Mardi Mulyo”, “Sumber Hasil” and “Ngudi Makmur” group in a row during one month arrived at IDR 703,292/had, IDR 2.157.250/had and IDR 1,649,395/had, respectively. In addition, SWOT analysis showed a total score of internal and external scores of 3.61 and 2.73. Based on the results of business development analysis of dairy cattle in West Ungaran District, it could be concluded that the dairy farm in category IV, stability strategy and coordinate points are in quadrant IV.