![Sample our Environment & Sustainability journals, sign in here to start your access, latest two full volumes FREE to you for 14 days]({"type":"image" , "src" : "/sda/5935/TOC-Subject-Sample-2021-Environment-Sustainability.jpg"})
Abstract
Iron (Fe) deficiency limits crop production on black calcareous soils (Typic Calciustolls) of Thailand with reports of Fe deficiency becoming more common. Much of the Fe in these soils occurs as free crystalline and amorphous Fe oxides and DTPA extractable Fe is low averaging 6. 4 mg/kg in 20 soils examined. Field studies showed that Fe deficiency could be alleviated by soil amendments such as elemental sulfur or by soil and foliar Fe fertilizer, provided rates of application were high enough. However, since soil amendment and Fe fertilizer use is costly, preliminary research into cultivar selection for Fe efficiency has begun with peanuts. Kernel yields in 20 cultivars were inversely related to Fe chlorosis scores. Standards for diagnosis and prediction of Fe deficiency in field crops are being developed for soil and plant analyses using DTPA and o‐phenanthroline, respectively.