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Drought is one of the climate change phenomena that has a profound impact on agricultural crops. Various adaptation strategies are used to deal with the impacts of climate change, one of which is the ratoon system of rice cultivation. This study aims to examine the effects of providing a combination of organic amendment and the application of PGPR on soil characteristics, growth, and yield of salibu ratoon system in the rainfed dry land. The research was conducted in Wonosari Village, Gondangrejo, Karanganyar, Central Java. This research used a complete randomized block design with three replications consisting of 2 factors. The first factor is the organic amendment, which is without the addition of organic matter (C1), compost (C2), and rice husk charcoal (C3). The second factor is the PGPR treatment, which is non-inoculated PGPR (P1) and inoculated PGPR (P2). Data analysis used ANOVA level of 5% followed by Duncan’s test. The results showed that the addition of organic matter and the inoculation of PGPR affected the variable root length, yield, and biomass. The addition of organic matter and PGPR can increase crop yields and plant resistance to drought stress by maintaining soil moisture and root elongation mechanisms. Based on the research results, the addition of rice husk charcoal and PGPR inoculation is the best combination for ratoon rice cultivation in the rainfed dry land.

Turmeric (Curcuma longa) and ginger (Zingiber officinale) are included in important spice commodities in Indonesia. The altitude and the environmental condition have an impact on the secondary metabolite content in the medicinal plants. Moreover, the current situation of climate change also affecting on the local environmental condition which is impacting on the secondary metabolite production. This research aims for determining the effects of altitude and soil characteristics on secondary metabolites. The research method was surveyed, then purposive sampling on farmlands with different altitude and soil characteristics at Karanganyar District, Indonesia. The variables observed were altitude, climate, soil characteristics (soil pH, Cation Exchange Capacity, Organic Matter, texture, Nitrogen, Phosphorus and Potassium), and secondary metabolites of turmeric and ginger (curcuminoid, gingerol, shogaol). The results indicated that the secondary metabolite of turmeric affected by altitude, soil pH, soil texture sand and soil available phosphorus. On the other hand, the secondary metabolites of ginger are affected by altitude, soil pH, soil organic matter, soil texture (silt and sand), and soil phosphorus. Turmeric and ginger in the highlands were produced more secondary metabolites compared with in lowlands.