Historical apple cultivars that display high level of resistance to fire blight

Following the first outbreak of fire blight caused by the bacterium Erwinia amylovora (Burrill) Winslow et al. in Hungary, we have started research with the aim to screen domestic gene sources, mostly historical Hungarian apple cultivars, for disease resistance as part of an apple breeding program for multiple resistance. The present study was conducted with the aim to choose the most tolerant historical apple cultivars among 25 selected cultivars by screening their behavior towards fire blight under controlled conditions. Six cultivars were shown to be the most disease tolerant: `Batul', 'London pepin', Nemes Sóvári Alma', `Sikulai', `Szemes alma', Wilmos renet'. We evaluated these cultivars by investigating both morphological- characteristics under original environmental circumstances and fruit quality. The cultivars had a remarkable degree of fire blight resistance compared to the control cultivars. These were not competitive with the commercially grown 'Jonathan M40' during cultivar tests but on the basis of certain characteristics they could serve as genetic sources for breeding new varieties.

Download Full-text

Testing of Czech cultivars and advanced selections of apples for fire blight (Erwinia amylovora) resistance

Horticultural Science ◽

10.17221/3784-hortsci ◽

2011 ◽

Vol 31 (No. 1) ◽

pp. 7-11

Author(s):

C. Fischer ◽

K. Richter ◽

J. Blažek

Keyword(s):

Fire Blight ◽

Erwinia Amylovora ◽

Scab Resistance ◽

Blight Resistance ◽

The Czech Republic ◽

Malus Floribunda ◽

Apple Cultivars ◽

High Level ◽

Very High ◽

Different Levels

Five apple cultivars from the Czech Republic and 26 selections from the same country (a majority of them were resistant to scab) were included in the present study. M. robusta strain (Nr. 5) was used as a control with the highest level of resistance to fire blight. Another 7 cultivars with different levels of resistance or susceptibility to the disease were also evaluated. Selena and Nabella were found to be resistant, whereas Angold, Resista and Topaz were susceptible. Two HL selections were previously identified as highly resistant, 3 selections as medium resistant and 7 others as moderately susceptible. The rest of the 14 selections ranged from very high susceptible to medium susceptible. A high level of resistance was confirmed in 3 cultivars from Dresden-Pillnitz: Reanda, Remo and Rewena. Comparison of the parentage of the tested cultivars or selections with their level of resistance to fire blight suggests that most of the resistance comes from Malus floribunda, which was used in the course of their breeding as a donor of scab resistance. In one case, the source of the fire blight resistance was Starking Delicious cv.  

Download Full-text

Fire Blight Resistance of Budagovsky 9 Apple Rootstock

Plant Disease ◽

10.1094/pdis-92-3-0385 ◽

2008 ◽

Vol 92 (3) ◽

pp. 385-391 ◽

Cited By ~ 6

Author(s):

Nicole L. Russo ◽

Terence L. Robinson ◽

Gennaro Fazio ◽

Herb S. Aldwinckle

Keyword(s):

Fire Blight ◽

Erwinia Amylovora ◽

Growth Habit ◽

Blight Resistance ◽

Apple Rootstock ◽

Apple Rootstocks ◽

Phenotypic Differences ◽

Age Related ◽

Multiple Trials ◽

High Level

Erwinia amylovora, the causal agent of fire blight, can cause a fatal infection of apple rootstocks known as rootstock blight. Budagovsky 9 (B.9) apple rootstock is reported to be highly susceptible when inoculated with E. amylovora, although results from multiple trials showed that B.9 is resistant to rootstock blight infection in field plantings. Conflicting results could stem from genetic variation in the B.9 population, appearing as phenotypic differences in rootstock material. However, genetic testing, using 23 microsatellite loci, confirmed the clonal uniformity of B.9 in commerce. Variation in growth habit between B.9 rootstocks originating from two nurseries also has been discounted as a source of disease resistance. Instead, results indicate a possible novel resistance phenotype in B.9 rootstock. B.9 rootstock was susceptible to leaf inoculation by E. amylovora, statistically similar to the susceptible rootstock Malling 9 (M.9). Conversely, inoculation assays targeting woody 4- to 5-year-old tissue revealed a high level of resistance in B.9, whereas M.9 remained susceptible. Although the mechanism by which B.9 gains resistance to E. amylovora is unknown, it is reminiscent of age-related resistance, due to an observed gain of resistance in woody rootstock tissue over succulent shoot tissue. Durable fire blight resistance correlated with tissue development could be a valuable tool for rootstock breeders.

Download Full-text

First selections of the Hungarian apple breeding program for multiple resistance

International Journal of Horticultural Science ◽

10.31421/ijhs/10/3/496 ◽

2004 ◽

Vol 10 (3) ◽

Author(s):

G. Tóth M. ◽

Kovács Sz. ◽

Kása K. ◽

Rozsnyay Zs. ◽

Hevesi M.

Keyword(s):

Fruit Quality ◽

Apple Scab ◽

Morphological Characteristics ◽

Breeding Program ◽

Multiple Resistance ◽

Apple Breeding ◽

Fruit Growing ◽

Apple Cultivars ◽

Selection For ◽

In The Beginning

The aim of the first Hungarian apple breeding program for multiple resistance started in the beginning of the nineties is to widen Hungarian apple assortment by good quality, resistant apple cultivars with excellent productivity and ecological capability to the most important fruit growing areas in Hungary. In the first years of seedling production we made early selection for susceptibility to apple scab in greenhouse. Alter this, field observation of susceptibility to powdery mildew, scab and canker and a yearly negative selection was carried on. From 1997, fruit quality was evaluated as well, and from 2001 the resistance of shoots to Erwinia ainylovora (Burrill/Winslow et al.) was examined using inoculations in greenhouse conditions. From the progenies of crosses in 1992 and 1993, six candidates were announced to national recognition out of hybrids examined for more than a decade. Descriptions of these selections from 'Prima' progenies and the most important data of their resistance, growing habit, morphological characteristics and fruit quality are shown in this article.

Download Full-text

First selections of the Hungarian apple breeding program for multiple resistance

International Journal of Horticultural Science ◽

10.31421/ijhs/10/3/479 ◽

2004 ◽

Vol 10 (3) ◽

Author(s):

M. G. Tóth ◽

Szabó Kovács ◽

K. Kása ◽

Zs. Rozsnyay ◽

M. Hevesi

Keyword(s):

Fruit Quality ◽

Apple Scab ◽

Morphological Characteristics ◽

Breeding Program ◽

Multiple Resistance ◽

Apple Breeding ◽

Fruit Growing ◽

Apple Cultivars ◽

Selection For ◽

In The Beginning

The aim of the first Hungarian apple breeding program for multiple resistance started in the beginning of the nineties is to widen Hungarian apple assortment by good quality, resistant apple cultivars with excellent productivity and ecological capability to the most important fruit growing areas in Hungary. In the first years of seedling production we made early selection for susceptibility to apple scab in greenhouse. Alter this, field observation of susceptibility to powdery mildew, scab and canker and a yearly negative selection was carried on. From 1997, fruit quality was evaluated as well, and from 2001 the resistance of shoots to Erwinia ainylovora (Burrill/Winslow et al.) was examined using inoculations in greenhouse conditions. From the progenies of crosses in 1992 and 1993, six candidates were announced to national recognition out of hybrids examined for more than a decade. Descriptions of these selections from 'Prima' progenies and the most important data of their resistance, growing habit, morphological characteristics and fruit quality are shown in this article.

Download Full-text