| Autor: |
Aryal SK; Entomology and Nematology Department, University of Florida, Gainesville, FL 32611., Crow WT; Entomology and Nematology Department, University of Florida, Gainesville, FL 32611., McSorley R; Entomology and Nematology Department, University of Florida, Gainesville, FL 32611., Giblin-Davis RM; Fort Lauderdale Research and Education Center, University of Florida, 3205 College Avenue, Davie, FL 33314., Rowland DL; Agronomy Department, University of Florida, Gainesville, FL 32611., Poudel B; Agronomy Department, University of Florida, Gainesville, FL 32611., Kenworthy KE; Agronomy Department, University of Florida, Gainesville, FL 32611. |
| Abstrakt: |
Understanding rooting dynamics using the minirhizotron technique is useful for cultivar selection and to quantify nematode damage to roots. A 2-yr microplot study including five bermudagrass ('Tifway', Belonolaimus longicaudatus susceptible; two commercial cultivars [TifSport and Celebration] and two genotypes ['BA132' and 'PI 291590'], which have been reported to be tolerant to B. longicaudatus) and two St. Augustinegrass ('FX 313', susceptible, and 'Floratam' that was reported as tolerant to B. longicaudatus) genotypes in a 5 x 2 and 2 x 2 factorial design with four replications, respectively, was initiated in 2012. Two treatments included were uninoculated and B. longicaudatus inoculated. In situ root images were captured each month using a minirhizotron camera system from April to September of 2013 and 2014. Mixed models analysis and comparison of least squares means indicated significant differences in root parameters studied across the genotypes and soil depths of both grass species. 'Celebration', 'TifSport' and 'PI 291590' bermudagrass, and 'Floratam' St. Augustinegrass had significantly different root parameters compared to the corresponding susceptible genotypes (P ≤ 0.05). Only 'TifSport' had no significant root loss when infested with B. longicaudatus compared to non-infested. 'Celebration' and 'PI 291590' had significant root loss but retained significantly greater root densities than 'Tifway' in B. longicaudatus-infested conditions (P ≤ 0.05). Root lengths were greater at the 0 to 5 cm depth followed by 5 to 10 and 10 to 15 cm of vertical soil depth for both grass species (P ≤ 0.05). 'Celebration', 'TifSport', and 'PI 291590' had better root vigor against B. longicaudatus compared to Tifway. |
