Coefficient of Variation from Vegetation Index for Sugarcane Population and Stalk Evaluation. Issue 1 (6th September 2018)

• Record Type: Journal Article
• Authors: Chanda, Saoli; Kanke, Yumiko; Dalen, Marilyn; Hoy, Jeffrey; Tubana, Brenda
• Is Part Of: Agrosystems, geosciences & environment. Volume 1:Issue 1(2018)
• Page Start: 1
• Page End: 9
• Publication Date: 2018-09-06
• Subjects: Agriculture -- Periodicals; Agriculture -- Environmental aspects -- Periodicals; Soil science -- Periodicals; Food science -- Periodicals; Food science; Agriculture; Agriculture -- Environmental aspects; Electronic journals; Periodicals; 630
• DOI: 10.2134/age2018.07.0016
• Languages: English
• ISSNs: 2639-6696

Abstract

Abstract : Core Ideas: Variety and planting material affect cane population and millable stalk production. Coefficient of variation from sensor readings decreases as cane canopy closes. Cane varieties for sugar and energy production differ greatly in canopy structure. Canopy structure influences sensor‐based profiling of cane population and stalk. Coefficient of variation (CV) is a statistical measure of variability in data. This study was conducted to evaluate the relationship of CV computed from Vegetation Indices (VIs) with plant population and millable stalk of different sugarcane ( Saccharrum spp.) varieties. Two experiments consisted of six cane varieties and two types of planting material (whole stalks vs. billets) with four replications arranged in a split plot in randomized block design were established in St. Gabriel, LA, in 2012 and 2013. Sensor readings were concurrently collected with plant population at 4 and 8 weeks after planting (WAP) and tiller count at early and late tillering stage. Variety had a more evident, consistent effect than planting material on population count, tiller number, and millable stalk ( p < 0.001). The regression analysis revealed: (i) a positive linear relationship between NDVI660 and CV660 with coefficient of determination ( r 2 ) of 0.49*** at 4 WAP, then changed to negative linear at 8 WAP and early tillering stage with r 2 values of 0.52*** and 0.75***, respectively; and (ii) CVs and VIs from the red‐edge band had consistently negative linear relationships ( p < 0.001), the strongest being at the early tillering stage ( r 2 = 0.61–0.73). The linear relationship of CV with plant population and millable stalk improved when variety was included as categorical variable. Future research should focus to categorize varieties into broader group based on canopy structure to develop more refined CV‐based model for fast profiling of cane plant stand population, tiller production, and millable stalk.