Response of Pear Genotypes to Psylla Sp. Attack in Central Transylvania, Romania

Susceptibility of European pear germplasm to Cacopsylla pyri under Mediterranean climatic conditions

“…On the whole, the number of resistant or highly tolerant cultivars made up the 8.1% of the investigated types, in agreement with other statements that no more than a minor portion of European pear genotypes show resistance or high tolerance to pear psylla damage (Benedek et al, 2010;Quarta and Puggioni, 1985;Sestras et al, 2009). The amount of slightly susceptible cultivars was 56.9% of the germplasm collection, while 24.4% of them were susceptible genotypes suffering medium or medium-high damage and 10.6% were highly susceptible cultivars that suffered heaviest damage.…”

“…All together the number of slightly susceptible cultivars were as much as 91 of the 160 ones investigated (Table 7). Large part of them were ancient cultivars of Italian origin, among them it is worth mentioning the interesting early ripening 'Precoce di Altedo' and 'Precoce di Fiorano', the late ripening 'Bella Angevina', 'Spadona' and 'Ammazzacavallo', the Tuscan 'Giugnolina', abundantly producing small and very aromatic fruits, 'Spadoncina' largely cultivated in the past in Southern Italy and still appreciated for fruit quality on local markets, and the famous 'Spina Carpi' also listed as highly tolerant by Braniste et al (1994), Quarta and Puggioni (1985), Robert and Raimbault (2005) and Sestras et al (2009). This group also includes the French late ripening 'Passe Crassane' and the commercially grown 'Abbé Fétel', 'Coscia', and 'Beurré Hardy', which on the contrary have been described as highly susceptible by other authors (Quarta and Puggioni, 1985;Stamenković et al, 1994).…”

“…Quarta and Puggioni (1985) found no more than 12% of the inspected genotypes (cultivar and selection) of medium-low susceptibility and no one of them was immune. Additionally, no more than 3.5% of the 486 Hungarian cultivars investigate by Benedek et al (2010) proved to be resistant and only 2.8% of them resulted highly tolerant to pear psylla damage; Sestras et al (2009) found more than 80% of total analyzed cultivars and selections to be susceptible to psylla.…”

“…Country of origin and year of release Notes Quarta and Puggioni (1985), to Stamenković et al (1994) and to Sestras et al (2009) three-year period of observation, typically ranging from near 40% to about 93% during May-September. Maximum humidity conditions also reached almost 100% during these months because of frequent rains.…”

“…Most of these studies were based on field observations (Benedek et al, 2010;Berrada et al, 1995;Bouvier et al, 2011;Braniste et al, 1994;Briolini et al, 1989;Quarta and Puggioni, 1985;Robert et al, 1999;Robert and Raimbault, 2005;Sestras et al, 2009;Stamenković et al, 1994;Szabó et al, 2010), while only few studies were made by the introduction of psylla nymphs or adults in a mesh covered tunnel containing the pear plants (Baldassarri et al, 1996;Pasqualini et al, 2006;Robert et al, 2004). On the contrary, nearly all studies performed in USA on C. pyricola resistance were carried out in the laboratory by rearing psylla nymphs on plant material (Bell, 1984(Bell, , 1992(Bell, , 2003(Bell, , 2013Bell and Stuart, 1990;Berrada et al, 1995;Butt et al, 1988Butt et al, , 1989Puterka et al, 1993;Quamme, 1984).…”