Spatial Autocorrelation among Different Levels of Genetic Homogeneity and Spacings in Loblolly Pine

• Published in: Forest science Vol. 61; no. 3; pp. 438 - 444
• Main Authors: Kim, Taek Joo, Bullock, Bronson P., McKeand, Steven E.
• Format: Journal Article
• Language: English
• Published: Bethesda Oxford University Press 01-06-2015
• Subjects: Cloning; Competition; Correlation analysis; Genetic engineering; Plantations; Planting; Studies; Trees; Trends; United States > US
• ISSN: 0015-749X; 1938-3738
• DOI: 10.5849/forsci.14-034

Spatial structures of differing levels of genetic homogeneity and spacing in loblolly pine stands were evaluated by estimating the spatial autocorrelation at the stand level. Four different levels of genetic homogeneity including clones, full-sib families, half-sib families, and a seed orchard mix were randomized into two spacings (3.0 × 6.1 m, 538 trees/ha; and 1.5 × 6.1 m, 1,077 trees/ha). The detrended stem diameters were assessed using a spatial autocorrelation parameter contained in a simultaneous autoregressive model and a standardized Moran's I statistic for the residuals. The results showed that 12.5% of the plots were positively autocorrelated and 5.0% of the plots were negatively autocorrelated at an α level of 0.10. It was found that spacing had an effect on both significant positive and negative spatial autocorrelations. A majority of positively and negatively autocorrelated plots were located in the wider spacing and closer spacing, respectively. No particular trend in terms of different levels of genetic homogeneity was noted except in one specific clone when planted at a wider spacing. Characterization of the spatial autocorrelation structure between individual trees at the stand level will aid in development of better models to represent on-the-ground stand conditions.