Evaluation of Soybean Greenness from Ground and Aerial Platforms and the Association with Leaf Nitrogen Concentration in Response to Drought. Issue 6 (1st November 2019)

• Record Type: Journal Article
• Authors: Bai, Hua; Purcell, Larry C.
• Is Part Of: Crop science. Volume 59:Issue 6(2019)
• Page Start: 2763
• Page End: 2773
• Publication Date: 2019-11-01
• Subjects: Crop science -- Periodicals; Cultures -- Périodiques; Cultures de plein champ -- Périodiques; Crop science; Nutzpflanzen; Zeitschrift; Pflanzenbau; Periodicals; 633
• DOI: 10.2135/cropsci2019.03.0159
• Languages: English
• ISSNs: 0011-183X

Abstract

ABSTRACT: Early senescence has been noted for soybean ( Glycine max [L.] Merr) exposed to drought. This research quantified the greenness of soybean canopy using digital image analysis throughout seedfilling for drought and well‐irrigated treatments. Five genotypes ranging from maturity groups (MGs) 2 to 5 were sown in field experiments for 3 yr. Leaf nitrogen (N) concentration decreased steadily throughout seedfill for all genotypes. The Dark Green Color Index (DGCI), which was determined from pictures taken from the ground, also decreased throughout the seedfill period for all genotypes, but did not indicate treatment differences between drought and well‐irrigated treatments. Aerial photographs taken from a height of 50 to 75 m also showed a progressive decline in DGCI values for all genotypes during seedfill, and also indicated that DGCI decreased faster and/or earlier in the season for the drought treatment than for the well‐irrigated treatment. The results demonstrated that aerial DGCI measurements have the promise to detect early senescence associated with drought, which may have applications in evaluating differences in sensitivity to drought among soybean genotypes.