The DSpace digital repository system captures, stores, indexes, preserves, and distributes digital research material. http://http://dspace.unitus.it:80 2013-05-19T19:52:04Z 2013-05-19T19:52:04Z Balestra, Giorgio M. Bucini, Danilo Paparatti, Bruno Speranza, Stefano Proietti Zolla, Cristina Pucci, Claudio Varvaro, Leonardo http://hdl.handle.net/2067/1190 2011-02-22T01:30:22Z 2004-12-31T23:00:00Z

Title: Bio-ethology of Anisandrus dispar F. and Its Possible Involvement in Dieback (Moria) Diseases of Hazelnut (Corylus avellana L.) Plants in Central Italy Authors: Balestra, Giorgio M.; Bucini, Danilo; Paparatti, Bruno; Speranza, Stefano; Proietti Zolla, Cristina; Pucci, Claudio; Varvaro, Leonardo Abstract: Hazelnut is one of the most important orchards in central Italy (Viterbo province). More than eighty phytophagous insect pests adversely affect hazelnut orchards, but only a few of these, such as Anisandrus dispar F. (Coleoptera, Scolytidae), induce severe damage. A bacterial disease (called moria) constitutes one of the main phytopathological problems of hazelnut plants in central Italy. Two years ago, the Lazio Regional Government and local hazelnut cooperatives supported a research into the bio-ethology of A. dispar and its possible association with moria disease on hazelnut plants in Viterbo. In 2003 and 2004 two experimental hazelnut areas were selected in the Capranica and Caprarola districts (Viterbo), where eighteen chemio-chromotrophic traps were installed to study the dynamic population of A. dispar and to catch live Scolytidae females. Representative samples of live A. dispar females were used to isolate and identify the bacterial populations present both out- side and inside the insects. After two years 5,726 A. dispar females had been caught. Of more than 1,400 live A. dispar females, 10% were submitted to microbiological ana- lyses by morphological, physiological, biochemical and molecular techniques. The populations of the main bacteria (by outside and inside) associated with the phyto- phagous were identified as Erwinia billingae, Brenneria quercina, Pantoea cedenensis and Pseudomonas spp. Studies are currently in progress to: i) clarify the biological cycle of A. dispar; ii) identify the role (direct and/or indirect) of the insect respect to the epidemiology of moria disease; iii) carry on pathogenicity tests on bacterial isolates to prove their involvement in bacteriosis; iv) develop specific primers to identify the presence of these bacteria when associated with the insect and with asymptomatic hazelnut plants; v) verify the influence of environmental parameters on the biology of both the insect and the disease.

2004-12-31T23:00:00Z Balestra, Giorgio Maria Rugini, Eddo Varvaro, Leonardo http://hdl.handle.net/2067/2182 2011-08-04T23:05:13Z 2000-12-31T23:00:00Z

Title: Increased susceptibility to Pseudomonas syringae pv. syringae and Pseudomonas viridiflava of kiwi plants having transgenic rolABC genes and its inheritance in the T1 offspring Authors: Balestra, Giorgio Maria; Rugini, Eddo; Varvaro, Leonardo Abstract: The staminate kiwi (Actinidia deliciosa A. Chev) cv. GTH (Late Yellow Hayward) showed high resistance to the pathogens Pseudomonas syringae pv. syringae and Pseudomonas viridiflava, contrary to the pistillate cv. Hayward which was highly susceptible to both bacteria. The resistant staminate GTH acquired susceptibility when transformed with rolABC of Agrobacterium rhizogenes. This susceptibility was inherited by the T1 offspring containing rolABC genes, derived by crossing pollen of transgenic rolABC GTH with the pistillate cv. Hayward. The susceptibility was probably correlated to high nitrogen content in the leaves of the rolABC plants. The higher susceptibility to P. s. pv. syringae than to P. viridiflava could be correlated with the high degree of auxin production by first bacterium. The high resistance to both bacteria of the staminate GTH was inherited by all the offspring lacking rolABC genes. The possibility of reducing susceptibility of rolABC plants to the pathogens by applying fewer fertilizers in the orchards, which would reduce both costs and environmental impact, is discussed. Description: L'articolo è disponibile sul sito del nuovo editore http://onlinelibrary.wiley.com

2000-12-31T23:00:00Z