Cedrus libani: the most susceptible Turkish conifer species to local Heterobasidion isolates in spring inoculations

Abstract

Five-year-old seedlings of Pinus nigra, Pinus brutia, Abies nordmanniana ssp. bornmü lleriana and Cedrus libani, 3-year-old seedlings of Pinus sylvestris, and 2-year-old seedlings of Juniperus excelsa were inoculated on the lower stem with Turkish Heterobasidion abietinum and Heterobasidion annosum s.s. isolates. In total, 300 seedlings were inoculated in April 2007 with five isolates of each Heterobasidion species and incubated in a glasshouse for 12 weeks. The daily maximum temperature increased gradually from 13°C to 31°C by the end of the incubation period. Infection incidence, mortality, lesion length in the inner bark and fungal growth in the xylem were examined. For H. abietinum, infection incidence ranged from 0% to 36%, and for H. annosum s.s. from 0% to 60%. Mortality was low; only 1% of the inoculated seedlings died. Mean lesion lengths varied between 7.6 and 11.9 mm for H. abietinum and 8.0 and 15.7 for H. annosum s.s. in all species apart from C. libani, in which the corresponding values were 42.2 and 42.6 mm respectively. Similarly, mean fungal growth in sapwood of C. libani was approximately 25 mm for both Heterobasidion species, in contrast to 0-3.2 mm in the other tree species. The H. abietinum isolates were not reisolated from P. nigra, P. sylvestris or J. excelsa. The H. annosum s.s. isolates did not infect Abies seedlings. Only P. brutia and C. libani were susceptible to both pathogens. Control seedlings showed no symptoms. The results indicated that C. libani is highly susceptible to Turkish isolates of Heterobasidion.

Pathogenicity of Spanish isolates of Heterobasidion annosum s. s. in Pinus pinaster seedlings

“…However, there was no difference in the mortality rate of the infected and control seedlings treated by soil infestation. Nevertheless, rates were similar to or even higher than observed by other authors (Lehtijarvi et al 2011;Scire et al 2011), who reported low mortality rates in other pine species, such as P. pinea, P. halepensis, P. nigra, P. sylvestris and P. brutia seedlings. The mortality rates (approximately 35 and 10% for stem inoculation and soil infestation, respectively) were lower than reported for some North American pine species, such as P. elliottii, P. echinata, P. palustris, P. strobus and P. taeda (Delatour et al 1998), and, to a lesser extent, for P. sylvestris (Swedjemark and Stenlid 1995), although inoculation methods were different from those used in this study.…”

“…1a). However, the lesion lengths were substantially higher than those observed in other pine species in Turkey, such as P. brutia (9.4 mm), P. nigra (15.7 mm) and P. sylvestris (15 mm) (Lehtijarvi et al 2011). The lesion lengths in stem inoculations were consistent with other findings in Picea abies (Swedjemark et al 2001), where an average lesion length of approximately 50 mm 182 days was found after inoculation.…”

“…The type of inoculum also affected lesion length: stem inoculation with woodchips caused more damage than stem inoculation with sawdust (N = 60, F = 10.14, p < 0.01). Furthermore, in the present study, the lesion lengths were measured 18 months after inoculation, whereas Lehtijarvi et al (2011) harvested the seedlings 12 weeks after inoculation. However, the lesion lengths were substantially higher than those observed in other pine species in Turkey, such as P. brutia (9.4 mm), P. nigra (15.7 mm) and P. sylvestris (15 mm) (Lehtijarvi et al 2011).…”

Pathogenicity ofHeterobasidion annosum(Fr.)Bref.sensu strictoon coniferous tree species inTurkey

“…Holmboe and P. sylvestris L. Based on inoculation experiments, however, C. libani appears the most susceptible native species to Turkish isolates of Heterobasidion (Lehtijärvi et al. ).…”

Susceptibility of Pinus nigra and Cedrus libani to Turkish Gremmeniella abietina isolates

“…Bref. (Lehtijärvi et al, 2011) and Sphaeropsis sapinea (Fr.) Dyko et Sutton (Doğmuş- Lehtijärvi et al, 2009) in mycelial inoculations -without being their natural host.…”