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

Gremmeniella abietina causes shoot dieback and stem cankers on conifers throughout Northern hemisphere. The aim of this study was to investigate the virulence of Turkish G. abietina isolates in a field experiment. The lower branches of 15-20-year-old P. nigra and C. libani in a plantation site at 1,050 m a.s.l. in Isparta were inoculated at 1-2-month intervals during September-January. Five isolates obtained from high altitude mountainous forests were used. Each isolate was inoculated into two branches per tree and repeated ten times on both tree species at each inoculation date. The branches were sampled at the end of February, and in August, and lesion lengths in the inner bark measured. The mean lesion length on P. nigra and C libani were 10.6 ± 0.8 and 3.8 ± 0.2 mm in February and 17.6 ± 1.4 and 7.8 ± 0.8 mm in August, respectively. Differences in the mean lesion length between the isolates were small. Nevertheless, there were significant differences between the isolates on P. nigra in November and January inoculations, and on C. libani at all four inoculation times. The mean lesion lengths for all isolates at both sampling dates was the highest (p < 0.01) in December inoculations for both P. nigra (22.0 ± 1.9 February; 32.9 ± 2.9 August) and C. libani (5.6 ± 0.7; 11.3 ± 1.2). There was no difference between the September and January inoculations on P. nigra, despite the almost six-fold difference in incubation period. During the December inoculations, the trees were most likely in winter dormancy, i.e. unable to defend themselves, which would explain the large lesions.

[1]  A. Lehtijärvi,et al.  Cedrus libani: the most susceptible Turkish conifer species to local Heterobasidion isolates in spring inoculations , 2011 .

[2]  I. Thomsen.  Precipitation and temperature as factors in Gremmeniella abietina epidemics , 2009 .

[3]  O. Rosvall,et al.  Genetic variation in responses of Pinus sylvestris trees to natural infection by Gremmeniella abietina , 2007 .

[4]  J. Heinonen,et al.  Conidial dispersal of Gremmeniella abietina: climatic and microclimatic factors , 2003 .

[5]  Margareta Karlman,et al.  Risks associated with the introduction of Pinus contorta in northern Sweden with respect to pathogens , 2001 .

[6]  P. Pulkkinen,et al.  Susceptibility of Six Scots Pine Clones to the Pathogenic Fungus Gremmeniella abietina , 2000 .

[7]  A. Uotila,et al.  Virulence of two Finnish Gremmeniella abietina types (A and B) , 1999 .

[8]  Per Hansson,et al.  Susceptibility of different provenances of Pinus sylvestris, Pinus contorta and Picea abies to Gremmeniella abietina , 1998 .

[9]  H. Butin.  Tree Diseases and Disorders: Causes, Biology, and Control in Forest and Amenity Trees , 1995 .

[10]  Per Hansson,et al.  Scleroderris canker on lodgepole pine introduced in northern Sweden , 1994 .

[11]  T. Kurkela,et al.  The susceptibility of Scots pine seedlings to Gremmeniella abietina: effect of growth phase, cold and drought stress , 1993 .

[12]  E. Aitken.  Susceptibility of four conifer species to Gremmeniella abietina , 1993 .

[13]  C. Upper,et al.  A conducive day concept to explain the effect of low temperature on the development of Scleroderris shoot blight. , 1989 .

[14]  T. Unestam,et al.  Infection experiments with Gremmeniella abietina on seedlings of Norway spruce and Scots pine , 1988 .

[15]  H. Solheim,et al.  Differences between provenances of pinus contort a var. latifolia in resistance to attack by gremmeniella abietina , 1987 .

[16]  R. Spear,et al.  The mode of infection and early stages of colonization of pines by Gremmeniella abietina , 1984 .

[17]  R. Spear,et al.  Effect of temperature on the ability of Gremmeniella abietina to survive and to colonize host tissue , 1984 .

[18]  F. Scholz,et al.  Physiological and Biochemical Factors in Austrian Pine Clones with Different Susceptibility to Gremmeniella abietina , 1984 .

[19]  P. Manion.  Scleroderris canker of conifers , 1984, Forestry Sciences.

[20]  S. Yokota,et al.  Scleroderris canker of Todo-fir in Hokkaido, Northern Japan. II. Physiological and pathological characteristics of the causal fungus , 1974 .

[21]  E. Donaubauer,et al.  Distribution and hosts of Scleroderris lagerbergii in Europe and North America , 1972 .

[22]  F. Roll‐Hansen,et al.  Scleroderris lagerbergii: Resistance and differences in attack between pine species and provenances , 1972 .

[23]  P. Spaulding.  Foreign diseases of forest trees of the world. , 1961 .