Mobilization of Iron from Calcareous Vertisol to Minimize Iron Deficiency Chlorosis of Soybean [Glycine max (L.) Merr.]

摘要

Iron deficiency chlorosis (IDC) is an abiotic nutritional stress prevalent in calcareous and high pH soils and its management is essential for realising better crop yield. In the present study, a pot culture experiment was conducted with the objectiveto minimise IDC in soybean using iron-efficient and responsive (FeER) soybean genotype viz. NRC-45 as test crop. An Fe inefficient and responsive (FeIR) genotype viz. IC-18374 was included in the study to compare the relative efficiency of contrasting genotype in mobilizing soil Fe. Twelve treatments were used in the experiment, which includes soil amendments such as sulphitation press mud (SPM) and iron pyrite applied either alone or in combination with micro- organisms like arbuscular mycorrhizal (AM) fungi or Piriformospora indica. Application of partially decomposed SPM in combination with Aspergillus niger to FeER genotype significantly improved the DTPA extractable Fe content of the soil from 2.20 to 5.75 mg kg1. Among the treatments, T6 comprised of FeER in combination with the application of 5 g SPM kg1, 12.5 mg FeS04 kg"1 and AM Fungi recorded the highest Fe concent-ration (59.7 mg g') in the stover at 60 days after sowing (DAS). Further, significantly higher chlorophyll content was observedin T6(2.55 mg g1) and T2(2.53 mg g1) at 60 DAS as compared to the T, (Control). Treatment consisting of 12.5 mg FeS04kg"' soil, partially decomposed SPM along with dual inoculation of AMF and Aspergillus niger to an FeER genotype of soybean was found tocontrol Fe deficiency chlorosis.