Susilawati H.L.,Indonesian Agricultural Environment Research Institute |
Susilawati H.L.,Chiba University |
Setyanto P.,Indonesian Agricultural Environment Research Institute |
Makarim A.K.,Indonesian Center for Food Crops Research and Development |
And 3 more authors.
Soil Science and Plant Nutrition | Year: 2015
The increasing human population requires greater rice production. However, rice cultivation contributes to global warming through greenhouse gas (GHG) emissions. Technologies for reducing GHG emissions in concert with the increased rice production from rice fields are needed. The objectives of this study were to evaluate the effects of steel slag applications on methane (CH4) and nitrous oxide (N2O) emissions and rice yields. Two study sites were established at the experimental farm belonging to Indonesian Agricultural Environment Research Institute (IAERI) in Jakenan and a farmer’s field in Wedarijaksa sub-district, Indonesia. Both field trials were conducted during the dry season (DS) of 2009 and the rainy season (RS) of 2009/2010. During the DS, a randomized block design was arranged with two treatments (a control and a steel slag application at 1 Mg ha−1), which were replicated five times. During the RS, the experimental plot with 1 Mg ha−1 of steel slag treatment was split into two small sub-plots to accommodate the additional 1 and 2 Mg ha−1 steel slag treatments. The results showed that there was a decreasing tendency in the CH4 emissions at both sites and during both seasons after steel slag applications, although there was no statistical significance. During the RS in Jakenan, steel slag applications at rates of 1 and 2 Mg ha−1 decreased the CH4 emissions by 9.1 and 10.7%, respectively. In Wedarijaksa, steel slag applications at rates of 1 and 2 Mg ha−1 decreased the CH4 emissions by 12.6 to 18.7%, respectively. The N2O emissions were decreased by 34 and 38% following slag applications at the 2 Mg ha−1 rate during the RS in Jakenan and Wedarijaksa, respectively. The iron content of steel slag could be used to reduce not only CH4 but also N2O emissions. Increased level of electron acceptors suppresses CH4 and N2O emissions. The application of steel slag at 1 and 2 Mg ha−1 increased rice grain yields by approximately 4.8–5.6% in Jakenan and 0.3–4.7% in Wedarijaksa. It might be better to apply steel slag at higher rates for more than two growing seasons to reach reduction in CH4 and N2O emissions. © 2015 Japanese Society of Soil Science and Plant Nutrition.
Manzanilla D.O.,International Rice Research Institute |
Paris T.R.,International Rice Research Institute |
Tatlonghari G.T.,International Rice Research Institute |
Tobias A.M.,International Rice Research Institute |
And 6 more authors.
Experimental Agriculture | Year: 2014
The risks of flooding in rice production include losses that can affect some 13 million ha of rice lands in Southeast Asia. This study integrated social and gender perspectives into the varietal evaluation process to contribute to planned faster uptake of submergence-tolerant rice (Sub1) varieties. In this study, the participatory varietal selection (PVS) process was used in eliciting male and female farmers' opinions with respect to selecting popular varieties with the SUB1 gene introgressed, for added tolerance of flash floods of up to two weeks. Fifteen Sub1 varieties and the farmers' local check were tested under the PVS researcher-managed (PVS-RM) trials, which involved farmers' preference analysis (PA). The farmers tested the pre-selected lines with the SUB1 gene in their own fields to further evaluate their performance under varying conditions. During flooding, farmers experienced lower production depending on water depth, timing with respect to rice growth stage, duration, frequency of occurrence and quality. On-farm PA results showed wide variability in the performance of the Sub1 varieties compared with local popular varieties. This implies the need for further testing of pre-released lines in terms of adaptability and the continuous development of rice genotypes for varying flood-prone rice ecosystems. Women are as knowledgeable as men because of the significant roles they play in rice production and food preparation. Moreover, farmers and breeders have almost the same criteria in choosing the best performing rice lines. Sensory tests revealed the eating and cooking qualities important to farmers. The findings of this study can provide feedback to breeding programmes to ensure a greater likelihood of adoption and ultimately increasing rice productivity in submergence-prone rice areas. Copyright © Cambridge University Press 2013.
Umboh S.J.K.,Bogor Agricultural University |
Umboh S.J.K.,Sam Ratulangi University |
Hakim D.B.,Bogor Agricultural University |
Sinaga B.M.,Bogor Agricultural University |
Kariyasa I.K.,Indonesian Center for Food Crops Research and Development
Media Peternakan | Year: 2014
This research aimed at analyzing the impact of maize price changes on the performance of small-scale broiler farming in Indonesia using a multimarket model analysis. The multimarket model analysis is partial equilibrium analysis that contains six blocks of equations: prices, supply, input demand, consumption, income and equilibrium. This model analysis was originally designed in General Algebric Modelling System (GAMS) using the Path NLP solver. Employed data in this study were classified into 3 types, namely: (1) production and input, consumption, and household income; (2) inputs and outputs, and (3) elasticities. Decreased domestic maize price was responded by farmer through reducing maize planted area and fertilizers uses. It further had undesired impact on the maize production and maize farmer's income. Whereas, this policy had positive impact on meat production and small-scale broiler farming income. The opposite impact will happen on those variables, if government increases domestic maize price. This policy caused the maize demand for feed industry decreased. As a result of this condition, it decreased the chicken meat production and small-scale broiler farming income.