ABSTRACT
Reducing methane emission from rainfed rice fields through utilizing amphibian rice cultivars

Anicetus Wihardjaka1*, Eni Yulianingsih2, Mas Teddy Sutriadi1, Terry Ayu Adriany1, Elisabeth Srihayu Harsanti3, Yulis Hindarwati1, and Sodiq Jauhari1
 
Rainfed rice (Oryza sativa L.) fields are the largest rice contributor after irrigated rice fields in Indonesia. As land is vulnerable to climate change impacts, optimizing the productivity of rainfed lowland rice is carried out, among other things, by utilizing superior amphibian rice cultivars. On the other hand, rainfed rice fields whose irrigation depends on rainfall are seen as a source of greenhouse gas emissions, especially methane. The research objective was to determine methane emissions from rainfed rice fields by using amphibian rice cultivars. The field research was conducted in a randomized block design with seven amphibian rice cultivars and the lowland ‘Ciherang’ as control. The changes measured included plant growth, grain yield, methane flux, and greenhouse gas intensity (GHGI). The tested amphibian rice cultivars emitted methane lower by 2.2%-35.3% than ‘Ciherang’. ‘Inpari 34’, ‘Inpari 39’, and ‘Inpari 42’ gave significantly lower GHGI values than other cultivars tested in rainfed rice fields, namely lower by 23.2%-31.5%, 8.1%-18.0%, 14.1%-23.4%, respectively. ‘Inpari 34’ is an amphibian cultivar that emits the lowest methane and releases the lowest CO2 per ton of grain produced. The cultivars of ‘Inpari 34’, ‘Inpari 39’, and ‘Inpari 42’ are considered suitable and adaptive for rainfed rice fields.
Keywords: Amphibian rice cultivar, carbon dioxide, grain yield, methane emission, Oryza sativa, rainfed rice fields.
1National Research and Innovation Agency, Cibinong Science Center, Indonesian Research Center for Food Crops, Jl. Raya Jakarta-Bogor, Cibinong 16915, Indonesia.
2Agricultural Ministry of Indonesia, Indonesian Agency for Agricultural Instrument Standardization (IAAIS), Indonesian Agricultural Environmental Standardization Institute (IAESI), Jakarta, Indonesia.
3National Research and Innovation Agency, Cibinong Science Center, Indonesian Research Center for Horticulture, Jl. Raya Jakarta-Bogor, Cibinong 16915, Indonesia.
*Corresponding author (awihardjaka@gmail.com).