Multiple Leaf Measurements Improve Effectiveness of Chlorophyll Meter for Durum Wheat Nitrogen Management

• DOI: 10.2135/cropsci2013.03.0160
• Publication Date: 2014-02-27T17:20:09Z
• Authors: Guangyao Wang; Kevin F. Bronson; Kelly R. Thorp; Jarai Mon; Mohammad Badaruddin
• Keywords: Crop Management; Growing season

ABSTRACT Simple and rapid methods are needed to measure durum wheat ( Triticum L.) nitrogen (N) status make on‐site N application decisions for increased crop yield grain quality. Although chlorophyll meters (SPAD meters) have been widely tested cereal management, significant variation in SPAD meter readings among growing seasons, locations, cultivars makes them challenging. Experiments with six fertilizer rates were conducted Arizona the 2010–2011 2011–2012 seasons test whether multiple leaf on same plants can improve estimation of by meters. The relationships between nutrition index (NNI) most recent fully expanded leaves (SPAD1), Sufficiency Index or normalized (SI), Normalized difference (NDSPAD), differences second (SPAD21) compared. results showed SPAD1 varied season, growth stage, cultivar. All three indices, SI, NDSPAD, SPAD21, improved prediction compared SPAD1. SI measured at Feekes 10.5 mean over stages (Feekes 5, 10, 10.5) performed better than other indices predicting yield. This study suggests that using SPAD21 effectiveness be as effective without requirement reference plots management.