Changes in soil fertility, growth and yield of ratoon rice (Oryza sativa L.) by application of soil amendment under drought stress

Rice (Oryza sativa L.) is a global staple food source with high demand. The influence of global climate change will impact rice production, one of which is drought condition. This research aims to determine the role of soil amendments on soil fertility, growth and yield of two rice varieties after ratooning on soil with low fertility under drought stress. The soil used in this study is Ultisol dryland from Jantho Aceh Besar, Indonesia. The study used a 3 x 2 x 2 split-split plot design with 3 replications. Soil amendments as the main plot consisted of vermicompost (7.5 g pot-1), AMF (7.5 g pot-1) and biofertilizer 17.64 mL L-1, which were given in main rice crop 5 days before planting, 14 DAP, 28 DAP and 42 DAP. Drought as a sub-plot consisting of normal soil watering and drought stress conditions and rice varieties as a sub of sub-plot, namely IPB 9G and Inpago 12 varieties. The parameters observed were soil fertility, growth of ratoon and rice yield. The results showed that the application of AMF during drought stress increased soil fertility as indicated by the ECe value for both varieties, respectively 282.33 µS cm -1 and 276.67 µS cm -1. The application of AMF also improves leaves chlorophyll content, plant height, number of tillers and number of plant leaves and yield. Rice productivity after ratooning reached 2.41 tons ha-1 in the IPB 9G variety and 1.84 tons ha-1 in the Inpago 12 variety under drought stress.