Treebreedex Seminar On IMPROVEMENT AND BREEDING OF NOBLE HARDWWOODS PATHOLOGY ASPECTS TO BE CONSIDERED IN NOBLE HARDWOODS Results after the PROJECT RISELVITALIA Evaluation of resistance to anthracnose, bacterial blight and root rots by Phytophthora in Juglans regia L. populations Prof. Naldo Anselmi PLANT PROTECTION DEPARTMENT UNIVERSITY OF TUSCIA Viterbo
HIGH QUALITY TIMBER BROADLEAF PLANTATIONS SUSFACE IN ITALY Total surface ~ 120.000 ha Juglans 40% Prunus 25% Juglans + Prunus 8% Fraxinus 2% Acer 1% Mixt 12% Authers 3%
Ri.Selv.Italia 1.1.4 MAIN AIMS ABOUT JUGLANS 1. TO ASSESS THE INCIDENCE AND THE DANGEROUSNESS OF THE DIFFERENT DISEASES OF JUGLANS (and other noble hardwoods) FOR TIMBER IN ITALY 2. TO DEFINE THEIR CAUSAL AGENTS (ETIOLOGY) 3. TO ESTIMATE THE RESISTANCE OF SOME JUGLANS POPULATIONS (AS PHENOTYPES, FAMILIES, PROVENANCES AND SPECIES) TOWARD THE MOST SERIOUS SPECIFIC DISEASES: ANTHRACNOSE BY MARSSONINA JUGLANDIS BACTERIAL BLIGHT BY XANTHOMONAS JUGLANDIS ROOT ROTS BY PHYTOPHTHORA SPP. (INK DISEASE) AND TRUNK CANKER, DISEASE OF COMPLEX ORIGIN (FOUND OUT AS ESPECIALLY HARMFUL)
MATERIALS AND METHODS 1. INCIDENCE AND DANGEROUSNESS OF THE DIFFERENT DISEASES Devoted surveys in commercial plantations of walnut for timber in several areas in Italy 2. ETIOLOGY In vitro isolation and identification of the pathogens by morphological analysis, selective substrate culturing and molecular analysis 3. RESISTANCE 1. MATERIALS Experimental multi-site plantations of Juglans populations assorted with phenotypes, half-sib families, provenances and species 2. METHODS Anthracnosis and Xanthomonas: leaves sampling in field and analytical examination in lab by assessment of: - n of necrosis/100 cm 2 of leaf surface - % of necrotic leaf surface Ink disease: % of symptomatic plants Trunk canker disease: % of diseased plants and n of cankers per plant.
MAIN DISEASES ON JUGLANS TRUNK CANKER BACTERIAL BLIGHT BY XANTHOMONAS CAMPESTRIS pv. ANTHRACNOSE BY GNOMONIA LEPTOSTYLA INK DISEASE
RESULTS 1. INCIDENCE AND DAMAGES Very serious: trunk canker = increasing incidence + heavy damages Serious: anthracnosis = widely diffused and recurrent Moderate: - Xanthomonas = poor diffusion and light damages - Ink disease = dangerous but very poorly diffused 2. ETIOLOGY Anthracnosis: Marssonina juglandis (tel. Gnomonia leptostyla) Ink disease: Phytophthora cinnamomi, P. cactorum and P. cambivora Trunk canker = complex disease: Brenneria nigrifluens + Botryosphaeria + Fusarium
3. RESISTANCE IN FIELD OF JUGLANS REGIA TOWARD MARSSONINA JUGLANDIS INVESTIGATED MATERIALS 6 plantations with different italian provenances of Juglans (~ 40 provenances, 100 half-sib families and 3500 genotypes); 1 plantation with 15 prov. of J. regia and 1 of J. nigra (~ 50 genotypes each); 1 plantation with 8 prov. of J. regia and 8 of J. nigra (~ 100 genotypes each); 1 plantation with 100 genotypes of J. regia; 100 genotypes of J. nigra; 100 genotypes of J. regia x J. nigra NG23; 100 genotypes of J. regia x J. nigra MJ209; 2 plantations with 20 species of Juglans; 10 prov. of J. regia and 10 of J. nigra.
BEHAVIOUR TOWARD ANTHRACNOSIS OF SOME PROVENIENCES OF JUGLANS REGIA (materials from Ducci)
RESULTS RESISTANCE IN FIELD 1. Marssonina Juglans regia: statistically significant differences in the resistance character were revealed only between provenances - Resistant provenances: Arboreto, Bleggio, Fontana, Carda, Cervia, Ponte Biforco - Moderately resistant provenances: Borgo alla Collina, Rifiglio, Ponte a Poppi - Susceptible provenances: Arcidosso, Arezzo, Garfagnana, Modena, Parma, Poppi, Scopetone, Venanza, ecc. J. nigra and J. regia x J. nigra hybrids: Resistant or moderately resistant 3. Trunk canker J. Regia: susceptible J. nigra and J. regia x J. nigra hybrids: Resistant or moderately resistant
CONCLUSIONS 1. J. regia is more or less susceptible toward Gnomonia leptostyla, but highly susceptible toward Xanthomonas and Trunk canker although a wide variability was observed among genotypes 2. J. nigra is resistant toward Gnomonia leptostyla, Xanthomonas and Trunk canker 3. The interspecific hybrids show an intermediate behaviour: CONCLUSIONS: It was already evidenced interesting genetic material to set up plantations for future planting of resistant material.
INCIDENCE AND DAMAGES OF THE MAIN DISEASES OF PRUNUS AVIUM FOR TIMBER Serious: leaf fall by CYLINDROSPORIUM PADI and CORYNEUM BEIJERIINCKII (= WILSONOMYCES CARPOPHILUS) Moderate: - Ink disease by Phytophthora = dangerous but poorly diffused - Plant decline = Complex disease
Leaf fall by CYLINDROSPORIUM PADI+ CORYNEUM BEIJERIINCKII
Plant decline in plantation of Prunus avium