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As an underground crop, tuberous root of sweet potato (Ipomoea batatas) is the main economical yield expected from various level of cultivation. Aside rich in carbohydrate, sweet potato root contains vitamin and mineral. The degree of utilization reflects the level of subsistence to commercialization, where the desire or needs can be easily met was defined as prosperity. Supplying continuously the demand of sweet potato for subsistence and commercialization oriented to bio-ethanol and food related industries depend on the sustainable production system. To sustain sweet potato production system, the severe biotic and a-biotic stresses have to be alleviated.

The main constraints of the tidal swamp lands in Indonesia for soybean growth are low soil pH, high Al saturation, and low nutrient availability of N, P, K, Ca, and Mg. The objectives of this research were to determine tolerance of several soybean varieties to Al saturation level, and to obtain a technological package for soybean cultivation which was suitable for farmers to adopt on tidal swamp lands. The research consisted of two stages of study. The first stage formulated of technology package, and the second stage evaluated feasibility of the technology package which was formulation from the first stage. The first stage  studied  the effect of  dolomite application (20% - 30% of soil Al saturation) on four soybean varieties (Anjasmoro, Panderman, Dega 1, and Demas). The second stage studied the effect of three technological packages: existing technology; water- saturated soybean cultivation (WSC); and alternative technology which was formulated from the results of the first study. In the 30% of soil Al saturation condition, the alternative technology package (application of 50 kg urea + 75 kg SP36 + 50 kg KCl + 1500 kg organic fertilizers/ha + rhizobium biofertilizer “Agriosy” 0.25 kg/50 g seeds/ha)  gave soybean yield of 1.78 - 2.72 t/ha for all of soybean varieties tested. The alternative technology package with Anjasmoro variety provided higher seed yields (2.62 t/ha) compared to the existing technology (2.07 t/ha) and WSC technology package (2.44 t/ha). The alternative technology package gave a profit of 11,595,000 IRD/ha with B/C values of 1.71 which was higer than the existing and WSC technology packages. The alternative technology package was more profitable than the existing technology (current farmer practice) and water-saturated soybean cultivation technology packages.

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Sixty percent of Indonesians live in Java, which in area is only around 7% of the country. As part of the global community, Indonesia has a strong endeavor to realize Millennium Development Goals (MDGs) which is put as a top priority to reduce hunger and alleviate poverty by 50% by 2015. Unfortunately, the severity of global warming has locked a dream into a reality. Praxis of past and present food crops production in the forest area of Java indicates that Java is able to feed not only domestic dwellers, but also those in the outer islands and even abroad. Unfortunately, due to food crop production practices there is a detrimental effect to the forest, so its basic function as a carbon sink is disturbed. The forest area of Java is 3.3 million ha, only around 2.5% of the Indonesian forest area. Around 73% of the Java forest is managed by Perhutani (State Forest Enterprise), and the 27% remaining is maintained by civilians. Apart from cereal and grain, which is more recognized as a food source, shade tolerant root-crops have a significant advantage by their ability to produce more food in the form of starchy roots under a greener environment. Future progress of agro-forestry should be able to keep a greener forest as a carbon sink in line with providing food sufficiently for dwellers.