Abstract

FERNANDO-LUIS, Irineo; SANCHEZ-RAMOS, Gerardo; MARTINEZ-AVALOS, José Guadalupe  and  REYES-CASTILLO, Pedro. Damage evaluation of (Lepidoptera: Tortricidae) (Heinrich): structural parameters and natural regeneration in Pinus nelsonii (Shaw) and P. cembroides ( Zucc.) in Miquihuana, Tamaulipas. Mexico. Acta Zool. Mex [online]. 2015, vol.31, n.3, pp.367-379. ISSN 2448-8445.

The present study aims to determine the damage intensity of the pinyon pitch nodule moth, Retinia arizonensis and their possible relationship to some structural parameters: stem diameter, height and coverage, as well as the natural regeneration of Pinus cembroides and P. nelsonii. For their evaluation, sites with 2,500 m² of each species were located. A total of 136 individuals of P. cembroides were recorded, with an average damage of 10.5% (±8.1 SD) in the terminal buds. In P. nelsonii, a total of 47 individuals were found, 46 exhibited damage from R. arizonensis, averaging 4.8% (±4.5 SD), twice less than P. cembroides. We used the Kruskal-Wallis (H-Chi²) to assess the damage of R. arizonensis between species, marked significant difference (p < 0.001) was observed. Relating to the structure, P. cembroides showed the following mean values: stem diameter = 10.7 cm (±8.0 SD), height = 2.9 m (±1.0 SD) and coverage = 3.0 m² (±1.8 SD). With respect to P. nelsonii, these were: stem diameter = 10.7 cm (±4.3), height = 3.6 m (±0.8) and coverage m² = 4.2 (±1.8), these variables showed wide statistical differences (p < 0.001). When measuring the association of R. arizonensis damage, with the structural variables, P. cembroides showed a positive marginal correlation with the variables height, diameter and covering with r² = 0.12, 0.16 and 0.18, respectively (p < 0.001). However, P. nelsonii expressed non-significant correlations among R. arizonensis damage with the structural parameters. The combined influence of the three structural variables (multiple correlation r²) of R. arizonensis damage, was mostly explained in P. cembroides with r² value of 0.19 highly significant (p < 0.001). In relation to P. nelsonii, the structural variables influenced on damage percentage of R. arizonensis were not significant (p = 0.128). Natural regeneration showed percentage participation (relative to adult trees) of 20.6% for P. cembroides and 42.5% for P. nelsonii with mean height of 13.9 cm (±12.6) and 28.4 cm (±20.0) in P. cembroides and P. nelsonii, respectively.

Keywords : Retinia arizonensis; P. cembroides; P. nelsonii; structure and natural regeneration.

        · abstract in Spanish     · text in Spanish     · Spanish ( pdf )