Improving Cassava Cultivation as an Industrial Raw Material on Acid Soil in Indonesia

Cassava is grown nowadays for use in food, feed, and industrial purposes. It is believed that the agro-industrial sector, which uses cassava as a raw material, has more advanced farming technology for improving cassava production. Lampung province in Sumatra Island, Indonesia, is one of the cassava production centers for industrial raw materials, with a planted area of 256,632 ha in 2018. The planting areas are acid soils of Ultisols, Inceptisols, and Oxisols with pH levels ranging from 4.5 to 5.0. Acidic soils have a complicated set of plant growth-limiting constraints. Essential nutrients for plant growth, such as N, P, and K, as well as other cations, are often low due to leaching, nutrients fixed by Fe/Al oxides of clay minerals, and low soil cation exchange capacity. In these acid soils, cassava production ranges from 8 to 15 t ha−1 for traditional farming, 20–24 t ha−1 for semi-developed farming to 25–35 t ha−1 for advanced farming. Meanwhile, with numerous technological advancements, cassava productivity can reach 40–50 t ha−1. Aside from improving varieties, technological updates being pursued include increasing the accuracy of mineral fertilizer dosage, improving planting system technology, bio-fertilizer technology, and in situ organic C enrichment of acid soils.