IN THE LAST DECADE THE ECONOMIC IMPORTANCE OF HYDRANGEA DISEASES ASSOCIATED WITH VIRUS AND PHYTOPLASMAS IN ITALY INCREASED THEREFORE EPIDEMIOLOGICAL SURVEYS WERE CARRIED OUT IN LIGURIA AND LAZIO REGIONS IN 2010 AND 2011. TO DETECT VIRUS INFECTIONS MECHANICAL INOCULATIONS ON HERBACEOUS PLANTS, ELECTRON MICROSCOPE OBSERVATIONS OF “LEAF-DIP” PREPARATIONS, SEROLOGY (PAS-ELISA AND ISEM TECHNIQUES) WERE EMPLOYED; TO VERIFY PHYTOPLASMAS PRESENCE AND TO DETERMINE THEIR IDENTITY, SAMPLES WERE TESTED BY NESTED-PCR, FOLLOWED BY RFLP ANALYSES ON 16S RIBOSOMAL GENE. IN 2011, HYDRANGEA PLANTS SHOWINGS STUNTING, FLOWER VIRESCENCE AND PHYLLODY, YELLOWING, NECROSIS AND REDNESS OF THE LEAF EDGE, WERE COLLECTED IN TWO COMMERCIAL GREENHOUSES OF “PIANA DI ALBENGA” (LIGURIA REGION). ALL SAMPLES (BELONGING TO THREE HYBRIDS) WERE INFECTED BY HYDRANGEA RINGSPOT VIRUS (HRSV). ONE OF THESE HYDRANGEA PLANTS, SHOWING ALSO FLOWER VIRESCENCE AND RED EDGES OF LEAVES, WAS INFECTED BY PHYTOPLASMAS BELONGING TO GROUP 16SRI-B (‘CANDIDATUS PHYTOPLASMA ASTERIS’). FURTHER RFLP CHARACTERIZATION OF THIS PHYTOPLASMA STRAIN ON THE GROEL GENE WITH TRU1I AND ALUI ALLOW ASSIGNING IT TO GROELI SUBGROUP III, REPORTED SO FAR ON SEVERAL EUROPEAN COUNTRIES. DURING INSPECTIONS PERFORMED IN THE BIENNIUM 2010-2011, SEVERE VIRUS-LIKE SYMPTOMS WERE OBSERVED IN ALMOST ALL HYDRANGEA PLANTS GROWING IN BOLSENA CITY (LAZIO REGION) SUCH AS STUNTING, LEAF AND FLOWER MALFORMATIONS, MOSAIC, CHLOROTIC AND NECROTIC MOTTLE, COLOUR-BREAKING ON PETALS. VIROLOGICAL TESTS REVEALED THE PRESENCE OF CUCUMBER MOSAIC VIRUS (CMV) IN THREE PLANTS CHARACTERIZED BY STUNTING, LEAF MOSAIC IN MALFORMED LEAVES AND FLOWER COLOUR-BREAKING. THE PRESENCE OF ELM MOTTLE VIRUS (EMOV; SYN. HYDRANGEA MOSAIC VIRUS) IN TWO PLANTS WITH SYMPTOMATIC LEAVES WAS ALSO DETECTED. MECHANICAL TRANSMISSION OF VIRUSES FROM HYDRANGEA WAS OBTAINED IN GOMPHRENA GLOBOSA WITH ALL THE IDENTIFIED VIRUSES BUT EMOV; THIS LATTER INDUCED SYSTEMIC INFECTION IN CHENOPODIUM QUINOA, HOWEVER ONLY SEROLOGICAL ANALYSES ALLOW TO IDENTIFY THE DIVERSE VIRUSES. IN 2011 ONE PLANT SHOWING GROWTH REDUCTION, FLOWER VIRESCENCE AND PHYLLODY, AND WITH ASYMPTOMATIC LEAVES WAS FOUND; MOLECULAR ANALYSES ALLOW TO IDENTIFY THE PRESENCE OF PHYTOPLASMAS BELONGING TO RIBOSOMAL SUBGROUP 16SRXII-A “STOLBUR”. FURTHER STRAIN CHARACTERIZATION CARRIED OUT ON STAMP AND TUF GENES CONFIRMED THE PRESENCE OF “STOLBUR” PHYTOPLASMAS. RFLP ANALYSES WITH TRU1I ON STAMP GENE SHOW THAT THE STRAIN INFECTING HYDRANGEA BELONGS TO ONE OF THE TWO GROUPS DIFFERENTIABLE IN “STOLBUR” PHYTOPLASMAS IN SOUTHERN EUROPE. LEAFHOPPERS PRESENT ON THIS LATTER PHYTOPLASMA-INFECTED PLANT WERE CAUGHT AND IDENTIFIED AS LAODELPHAX STRIATELLUS, ANACERATOGALLIA SP., EMPOASCA DECIPIENS, EMPOASCA SP., ASYMMETRASCA DECEDENS, ZYGINIDIA PULLULA. DNA FROM IDENTIFIED SPECIMENS MAINTAINED IN 100% ETHANOL WAS EXTRACTED AND TESTED BY NESTED-PCR/RFLP ANALYSES ON 16S RIBOSOMAL GENE AND TUF GENES. ‘CA. P. ASTERIS’-RELATED PHYTOPLASMAS WERE IDENTIFIED IN L. STRIATELLUS WHILE “STOLBUR” (16SRXII-A) PHYTOPLASMAS WERE PRESENT IN ANACERATOGALLIA SPP. CMV AND EMOV HAVE BEEN DETECTED IN THIS SPECIES FOR THE FIRST TIME IN ITALY; IN ADDITION, UNTIL NOW, ONLY PHYTOPLASMAS BELONGING TO SUBGROUP 16SRI-B (ASTER YELLOWS) HAVE BEEN FOUND INFECTING HYDRANGEA IN ITALY AND WORLDWIDE. HOWEVER 16SRXII-A PHYTOPLASMAS WERE ONLY REPORTED IN HYDRANGEA IN BULGARIA MORE THAN 15 YEARS AGO IN MIXED INFECTION WITH ASTER YELLOWS, THIS IS THEREFORE THE FIRST CONFIRMATION OF STOLBUR PHYTOPLASMA PRESENCE ASSOCIATED WITH VIRESCENCE OF H. MACROPHYLLA. EPIDEMIOLOGICAL SURVEYS WERE CARRIED OUT IN LIGURIA AND LAZIO REGIONS IN 2010 AND 2011 TO DETECT VIRUS AND PHYTOPLASMA INFECTIONS IN HYDRANGEA MACHROPHYLLA BY APPLYING (FOR VIRUS PRESENCE) MECHANICAL INOCULATIONS ON HERBACEOUS PLANTS, ELECTRON MICROSCOPE OBSERVATIONS OF “LEAF-DIP” PREPARATIONS, SEROLOGY (PAS-ELISA AND ISEM TECHNIQUES) AND (FOR PHYTOPLASMA PRESENCE) NESTED-PCR, FOLLOWED BY RFLP ANALYSES ON 16S RIBOSOMAL GENE. HYDRANGEA PLANTS SHOWINGS STUNTING, FLOWER VIRESCENCE AND PHYLLODY, YELLOWING, NECROSIS AND REDNESS OF THE LEAF EDGE, COLLECTED IN TWO COMMERCIAL GREENHOUSES OF “PIANA DI ALBENGA” (LIGURIA REGION), WERE INFECTED BY HYDRANGEA RINGSPOT VIRUS (HRSV); ONE OF THESE HYDRANGEA PLANTS, SHOWING ALSO FLOWER VIRESCENCE AND RED EDGES OF LEAVES, WAS INFECTED BY PHYTOPLASMAS BELONGING TO GROUP 16SRI-B (‘CANDIDATUS PHYTOPLASMA ASTERIS’) GROELI SUBGROUP III. ALMOST ALL HYDRANGEA PLANTS GROWING IN BOLSENA CITY (LAZIO REGION) SHOWED SEVERE SYMPTOMS: CUCUMBER MOSAIC VIRUS (CMV) INFECTED THREE PLANTS CHARACTERIZED BY STUNTING, LEAF MOSAIC IN MALFORMED LEAVES AND FLOWER COLOUR-BREAKING; ELM MOTTLE VIRUS (EMOV; SYN. HYDRANGEA MOSAIC VIRUS) INFECTED TWO PLANTS WITH SYMPTOMATIC LEAVES. ONE PLANT SHOWING GROWTH REDUCTION, FLOWER VIRESCENCE AND PHYLLODY WAS FOUND INFECTED BY PHYTOPLASMAS BELONGING TO RIBOSOMAL SUBGROUP 16SRXII-A “STOLBUR”. LEAFHOPPERS PRESENT ON THIS LATTER PHYTOPLASMA-INFECTED PLANT WERE CAUGHT AND IDENTIFIED AS LAODELPHAX STRIATELLUS, ANACERATOGALLIA SP., EMPOASCA DECIPIENS, EMPOASCA SP., ASYMMETRASCA DECEDENS, ZYGINIDIA PULLULA. ‘CA. P. ASTERIS’-RELATED PHYTOPLASMAS WERE IDENTIFIED IN L. STRIATELLUS WHILE “STOLBUR” (16SRXII-A) PHYTOPLASMAS WERE PRESENT IN ANACERATOGALLIA SPP. CMV AND EMOV HAVE BEEN DETECTED IN THIS SPECIES FOR THE FIRST TIME IN ITALY; IN ADDITION, UNTIL NOW, ONLY PHYTOPLASMAS BELONGING TO SUBGROUP 16SRI-B (ASTER YELLOWS) HAVE BEEN FOUND INFECTING HYDRANGEA IN ITALY AND WORLDWIDE. HOWEVER 16SRXII-A PHYTOPLASMAS WERE ONLY REPORTED IN HYDRANGEA IN BULGARIA MORE THAN 15 YEARS AGO IN MIXED INFECTION WITH ASTER YELLOWS, THIS IS THEREFORE THE FIRST CONFIRMATION OF STOLBUR PHYTOPLASMA PRESENCE ASSOCIATED WITH VIRESCENCE OF H. MACROPHYLLA.
A. BERTACCINI, S. PALTRINIERI, N. CONTALDO, N. MORI, L. CAVICCHI, M.G. BELLARDI (2015). SEVERE DISEASES INDUCED BY VIRUSES AND PHYTOPLASMAS IN HYDRANGEA IN ITALY. ACTA HORTICULTURAE, 1072, 105-111.
SEVERE DISEASES INDUCED BY VIRUSES AND PHYTOPLASMAS IN HYDRANGEA IN ITALY
BERTACCINI, ASSUNTA;PALTRINIERI, SAMANTA;CONTALDO, NICOLETTA;CAVICCHI, LISA;BELLARDI, MARIA GRAZIA
2015
Abstract
IN THE LAST DECADE THE ECONOMIC IMPORTANCE OF HYDRANGEA DISEASES ASSOCIATED WITH VIRUS AND PHYTOPLASMAS IN ITALY INCREASED THEREFORE EPIDEMIOLOGICAL SURVEYS WERE CARRIED OUT IN LIGURIA AND LAZIO REGIONS IN 2010 AND 2011. TO DETECT VIRUS INFECTIONS MECHANICAL INOCULATIONS ON HERBACEOUS PLANTS, ELECTRON MICROSCOPE OBSERVATIONS OF “LEAF-DIP” PREPARATIONS, SEROLOGY (PAS-ELISA AND ISEM TECHNIQUES) WERE EMPLOYED; TO VERIFY PHYTOPLASMAS PRESENCE AND TO DETERMINE THEIR IDENTITY, SAMPLES WERE TESTED BY NESTED-PCR, FOLLOWED BY RFLP ANALYSES ON 16S RIBOSOMAL GENE. IN 2011, HYDRANGEA PLANTS SHOWINGS STUNTING, FLOWER VIRESCENCE AND PHYLLODY, YELLOWING, NECROSIS AND REDNESS OF THE LEAF EDGE, WERE COLLECTED IN TWO COMMERCIAL GREENHOUSES OF “PIANA DI ALBENGA” (LIGURIA REGION). ALL SAMPLES (BELONGING TO THREE HYBRIDS) WERE INFECTED BY HYDRANGEA RINGSPOT VIRUS (HRSV). ONE OF THESE HYDRANGEA PLANTS, SHOWING ALSO FLOWER VIRESCENCE AND RED EDGES OF LEAVES, WAS INFECTED BY PHYTOPLASMAS BELONGING TO GROUP 16SRI-B (‘CANDIDATUS PHYTOPLASMA ASTERIS’). FURTHER RFLP CHARACTERIZATION OF THIS PHYTOPLASMA STRAIN ON THE GROEL GENE WITH TRU1I AND ALUI ALLOW ASSIGNING IT TO GROELI SUBGROUP III, REPORTED SO FAR ON SEVERAL EUROPEAN COUNTRIES. DURING INSPECTIONS PERFORMED IN THE BIENNIUM 2010-2011, SEVERE VIRUS-LIKE SYMPTOMS WERE OBSERVED IN ALMOST ALL HYDRANGEA PLANTS GROWING IN BOLSENA CITY (LAZIO REGION) SUCH AS STUNTING, LEAF AND FLOWER MALFORMATIONS, MOSAIC, CHLOROTIC AND NECROTIC MOTTLE, COLOUR-BREAKING ON PETALS. VIROLOGICAL TESTS REVEALED THE PRESENCE OF CUCUMBER MOSAIC VIRUS (CMV) IN THREE PLANTS CHARACTERIZED BY STUNTING, LEAF MOSAIC IN MALFORMED LEAVES AND FLOWER COLOUR-BREAKING. THE PRESENCE OF ELM MOTTLE VIRUS (EMOV; SYN. HYDRANGEA MOSAIC VIRUS) IN TWO PLANTS WITH SYMPTOMATIC LEAVES WAS ALSO DETECTED. MECHANICAL TRANSMISSION OF VIRUSES FROM HYDRANGEA WAS OBTAINED IN GOMPHRENA GLOBOSA WITH ALL THE IDENTIFIED VIRUSES BUT EMOV; THIS LATTER INDUCED SYSTEMIC INFECTION IN CHENOPODIUM QUINOA, HOWEVER ONLY SEROLOGICAL ANALYSES ALLOW TO IDENTIFY THE DIVERSE VIRUSES. IN 2011 ONE PLANT SHOWING GROWTH REDUCTION, FLOWER VIRESCENCE AND PHYLLODY, AND WITH ASYMPTOMATIC LEAVES WAS FOUND; MOLECULAR ANALYSES ALLOW TO IDENTIFY THE PRESENCE OF PHYTOPLASMAS BELONGING TO RIBOSOMAL SUBGROUP 16SRXII-A “STOLBUR”. FURTHER STRAIN CHARACTERIZATION CARRIED OUT ON STAMP AND TUF GENES CONFIRMED THE PRESENCE OF “STOLBUR” PHYTOPLASMAS. RFLP ANALYSES WITH TRU1I ON STAMP GENE SHOW THAT THE STRAIN INFECTING HYDRANGEA BELONGS TO ONE OF THE TWO GROUPS DIFFERENTIABLE IN “STOLBUR” PHYTOPLASMAS IN SOUTHERN EUROPE. LEAFHOPPERS PRESENT ON THIS LATTER PHYTOPLASMA-INFECTED PLANT WERE CAUGHT AND IDENTIFIED AS LAODELPHAX STRIATELLUS, ANACERATOGALLIA SP., EMPOASCA DECIPIENS, EMPOASCA SP., ASYMMETRASCA DECEDENS, ZYGINIDIA PULLULA. DNA FROM IDENTIFIED SPECIMENS MAINTAINED IN 100% ETHANOL WAS EXTRACTED AND TESTED BY NESTED-PCR/RFLP ANALYSES ON 16S RIBOSOMAL GENE AND TUF GENES. ‘CA. P. ASTERIS’-RELATED PHYTOPLASMAS WERE IDENTIFIED IN L. STRIATELLUS WHILE “STOLBUR” (16SRXII-A) PHYTOPLASMAS WERE PRESENT IN ANACERATOGALLIA SPP. CMV AND EMOV HAVE BEEN DETECTED IN THIS SPECIES FOR THE FIRST TIME IN ITALY; IN ADDITION, UNTIL NOW, ONLY PHYTOPLASMAS BELONGING TO SUBGROUP 16SRI-B (ASTER YELLOWS) HAVE BEEN FOUND INFECTING HYDRANGEA IN ITALY AND WORLDWIDE. HOWEVER 16SRXII-A PHYTOPLASMAS WERE ONLY REPORTED IN HYDRANGEA IN BULGARIA MORE THAN 15 YEARS AGO IN MIXED INFECTION WITH ASTER YELLOWS, THIS IS THEREFORE THE FIRST CONFIRMATION OF STOLBUR PHYTOPLASMA PRESENCE ASSOCIATED WITH VIRESCENCE OF H. MACROPHYLLA. EPIDEMIOLOGICAL SURVEYS WERE CARRIED OUT IN LIGURIA AND LAZIO REGIONS IN 2010 AND 2011 TO DETECT VIRUS AND PHYTOPLASMA INFECTIONS IN HYDRANGEA MACHROPHYLLA BY APPLYING (FOR VIRUS PRESENCE) MECHANICAL INOCULATIONS ON HERBACEOUS PLANTS, ELECTRON MICROSCOPE OBSERVATIONS OF “LEAF-DIP” PREPARATIONS, SEROLOGY (PAS-ELISA AND ISEM TECHNIQUES) AND (FOR PHYTOPLASMA PRESENCE) NESTED-PCR, FOLLOWED BY RFLP ANALYSES ON 16S RIBOSOMAL GENE. HYDRANGEA PLANTS SHOWINGS STUNTING, FLOWER VIRESCENCE AND PHYLLODY, YELLOWING, NECROSIS AND REDNESS OF THE LEAF EDGE, COLLECTED IN TWO COMMERCIAL GREENHOUSES OF “PIANA DI ALBENGA” (LIGURIA REGION), WERE INFECTED BY HYDRANGEA RINGSPOT VIRUS (HRSV); ONE OF THESE HYDRANGEA PLANTS, SHOWING ALSO FLOWER VIRESCENCE AND RED EDGES OF LEAVES, WAS INFECTED BY PHYTOPLASMAS BELONGING TO GROUP 16SRI-B (‘CANDIDATUS PHYTOPLASMA ASTERIS’) GROELI SUBGROUP III. ALMOST ALL HYDRANGEA PLANTS GROWING IN BOLSENA CITY (LAZIO REGION) SHOWED SEVERE SYMPTOMS: CUCUMBER MOSAIC VIRUS (CMV) INFECTED THREE PLANTS CHARACTERIZED BY STUNTING, LEAF MOSAIC IN MALFORMED LEAVES AND FLOWER COLOUR-BREAKING; ELM MOTTLE VIRUS (EMOV; SYN. HYDRANGEA MOSAIC VIRUS) INFECTED TWO PLANTS WITH SYMPTOMATIC LEAVES. ONE PLANT SHOWING GROWTH REDUCTION, FLOWER VIRESCENCE AND PHYLLODY WAS FOUND INFECTED BY PHYTOPLASMAS BELONGING TO RIBOSOMAL SUBGROUP 16SRXII-A “STOLBUR”. LEAFHOPPERS PRESENT ON THIS LATTER PHYTOPLASMA-INFECTED PLANT WERE CAUGHT AND IDENTIFIED AS LAODELPHAX STRIATELLUS, ANACERATOGALLIA SP., EMPOASCA DECIPIENS, EMPOASCA SP., ASYMMETRASCA DECEDENS, ZYGINIDIA PULLULA. ‘CA. P. ASTERIS’-RELATED PHYTOPLASMAS WERE IDENTIFIED IN L. STRIATELLUS WHILE “STOLBUR” (16SRXII-A) PHYTOPLASMAS WERE PRESENT IN ANACERATOGALLIA SPP. CMV AND EMOV HAVE BEEN DETECTED IN THIS SPECIES FOR THE FIRST TIME IN ITALY; IN ADDITION, UNTIL NOW, ONLY PHYTOPLASMAS BELONGING TO SUBGROUP 16SRI-B (ASTER YELLOWS) HAVE BEEN FOUND INFECTING HYDRANGEA IN ITALY AND WORLDWIDE. HOWEVER 16SRXII-A PHYTOPLASMAS WERE ONLY REPORTED IN HYDRANGEA IN BULGARIA MORE THAN 15 YEARS AGO IN MIXED INFECTION WITH ASTER YELLOWS, THIS IS THEREFORE THE FIRST CONFIRMATION OF STOLBUR PHYTOPLASMA PRESENCE ASSOCIATED WITH VIRESCENCE OF H. MACROPHYLLA.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
