Frozen versus non‐frozen sample preparation for plant tissue phosphorus analysis

Abstract

Abstract Maize (Zea mays L.) and wheat (Triticum aestivum L.) plant tissue was collected from phosphorus fertility experiments at two locations in 1985. Two samples were collected from each experimental unit and randomly either frozen immediately following collection or stored and dried normally prior to being analyzed for total P (HNO3‐HC1O4acid digest) and inorganic P (CH3COOH extract). Corn was sampled at the eight and twelve leaf stages and wheat at Feekes stage five. Freezing was accomplished using liquid N (wheat‐Feekes stage five) and dry ice (corn‐eight and twelve leaf stages). Inorganic P was found to be greater when frozen at the twelve leaf stage versus the conventional non freezing procedure. Alternatively, the opposite was found for wheat at Feekes stage five. The freezing procedure was found to increase the total P concentration for both corn at the twelve leaf stage and wheat at Feekes stage five. Losses of CO2were expected in the conventional non‐frozen samples due to an induced leaf respi...