title: Effects of biochar on enhanced nutrient use efficiency of green bean, Vigna radiata L.
abstract: Biochar is the carbonized material produced from biomass and is used in several environmental applications. The biochar characteristics depend on the carbonization conditions and feedstock. The suitability of a given biochar for soil improvement depends on the biochar characteristics, soil properties, and target plants. Biochar has been applied at 1-20% (w/w) in the soil, but currently there is a lack of information on what type and concentration of biochar are most suitable for a specific plant and soil quality. Too much biochar will reduce plant growth because of the high alkalinity of biochar, which will cause long-term soil alkalinity. In contrast, too little biochar might be insufficient to enhance plant productivity. In this study, a suitable concentration of cassava stem (an abundant agricultural waste in Thailand) biochar produced at 350 °C was evaluated for green bean (Vigna radiata L.) growth from germination to seed production in pots over 8 weeks. The soil fertility was increased with increasing biochar concentration. At 5% (w/w) biochar, the soil fertility and plant growth were significantly enhanced, while 10% (w/w) biochar significantly enhanced bean growth and bean pod production. The increased biochar concentration in the soil significantly increased the soil total nitrogen and extractable potassium (K) levels but did not affect the amount of available phosphorous. Biochar at 10% (w/w) significantly induced the accumulation of K in the stems, leaves, nut shells, and roots but not in nut seeds. Moreover, biochar not only increased the K concentration in soil but also increased the plant nutrient use efficiency of K, which is important for plant growth. Graphical abstract ᅟ.
authors.affiliation: Environmental Research Institute, Chulalongkorn University, Pathumwan, Bangkok, 10330, Thailand. songkrit.p@chula.ac.th.
authors.forename: Songkrit
authors.identifier: http://orcid.org/0000-0002-3425-9147
authors.initials: S
authors.lastname: Prapagdee
authors.affiliation: Department of Plant Production Technology, Faculty of Agricultural Technology, King Mongkut's Institute of Technology Ladkrabang, Ladkrabang, Bangkok, 10520, Thailand.
authors.forename: Nukoon
authors.initials: N
authors.lastname: Tawinteung
mesh_terms: D002606:Charcoal; D012987:Soil; D013785:Thailand; D000070658:Vigna
chemical_list: D012987:Soil; C540010:biochar; D002606:Charcoal
keywords: Cassava stem biochar; Green bean; Nutrient use efficiency; Soil fertility; Vigna radiata L