Salt Tolerance and Canopy Reflectance of Kentucky Bluegrass Cultivars

• Published in: HortScience Vol. 45; no. 6; pp. 952 - 960
• Main Authors: Poss, James A, Russell, Walter B, Bonos, Stacy A, Grieve, Catherine M
• Format: Journal Article
• Language: English
• Published: Alexandria, VA American Society for Horticultural Science 01.06.2010
• Subjects: Agronomy. Soil science and plant productions; Biological and medical sciences; canopy; chemical constituents of plants; cultivars; Floating Water Band Index; Fundamental and applied biological sciences. Psychology; genetic variation; Genetics and breeding of economic plants; germplasm evaluation; hybrids; hyperspectral imagery; leaves; measurement; Normalized Difference Vegetation Index; plant growth; Poa pratensis; quantitative analysis; reflectance; remote sensing; salinity; salt stress; salt tolerance; sodium chloride; turf grasses; California; Monocotyledones; Salt resistance; salinity stress; Environmental factor; Biomass; Remote sensing; relative moisture content; Spectral data; Gramineae; Optical properties; Angiospermae; Water content; C3-Type; kentucky bluegrass selections; Halotolerance; Composition; Vegetals; Tolerance; Plant leaf; hyperspectral leaf reflectance; Physical properties; Stress; Salinity; Turf; Vegetative apparatus; Hyperspectral characteristic; Poa pratensis; Water quality; Herbaceous plant; Spermatophyta; Canopy(vegetation); Cultivar; Reflectance
• ISSN: 0018-5345; 2327-9834
• DOI: 10.21273/hortsci.45.6.952

Six cultivars or selections of kentucky bluegrass (Poa pratensis L.) were grown outdoors from vegetative clones in a gravelly sand medium from Apr. to Sept. 2005 in Riverside, CA, at soil water salinities ranging from 2 to 22 dS·m–1. Cultivars Baron, Brilliant, Cabernet, Eagleton, Midnight, and the selection A01-856, a ‘Texas’ x kentucky bluegrass hybrid (P.· arachnifera x P. pratensis), were evaluated for salt tolerance based on relative and absolute cumulative biomass production, growth rates, leaf chloride concentration, and hyperspectral ground-based remote sensing (RS) canopy reflectance measurements. Remotely sensed indices were linearly correlated with absolute biomass production. Three variations of a Normalized Difference Vegetation Index (NDVIred, NDVIprotein, and NDVIinfra) decreased with increasing salinity-induced changes in grass canopies. An index based on the red-edge inflection point increased (became less negative) with increasing salinity. A Floating Water Band Index decreased with decreased leaf moisture content related to increasing salinity but did not discriminate between cultivars. Shoot spreading rate and NDVIinfra were both related to shoot chloride concentration differences among the kentucky bluegrass (Poa pratensis L) (KBG) cultivars or selections. In theory, non-destructive RS monitoring of above-ground turf development, including NDVIinfra, coupled with measurement of leaf chloride concentrations could be useful in turf salt tolerance breeding programs. Salt tolerance rankings among the KBG cultivars varied depending on the evaluation methods and selection criteria used. Based on absolute and relative biomass, growth rate, and RS, cultivars Baron, Brilliant, and Eagleton were rated as more salt-tolerant than ‘Cabernet’, ‘Midnight’, and AO1-856.