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• Brown rot blossom blight of pome and stone fruits: symptom, disease cycle, host resistance, and biological control

  15-21.

  I. J. Holb

  Views:

  901

  In this paper, important features of symptoms, biology and biological disease management are summarised for brown rot blossom blight fungi of pome and stone fruit crops (Monilinia laxa, Monilinia fructicola and Monilinia mali). Firstly, European brown rot caused by Monilinia laxa is discussed highlighting the blossom epidemiology features, then host susceptibility of the most important stone fruit species including several Hungarian and international cultivars. At the end of this chapter, recent biological control possibilities against Monilinia laxa are also included. Secondly, American brown rot caused by Monilinia fructicola is discussed. Symptoms, biological features of blossom blight and host susceptibility of flowers to Monilinia fructicola are demonstrated. Finally, the symptoms and the biology of the least frequent species, Monilinia mali are shown.

• In vitro sensitivity of Monilinia laxa to fungicides approved in integrated and organic production systems

  59-61.

  I. J. Holb

  M. Fazekas

  F. Abonyi

  Views:

  233

  The aim of this study was to test the in vitro sensitivity of two isolates of Monilinia laxa to fungicides approved in integrated and organic production systems. In vitro efficacy of 7 fungicides (Champion 50 WP, Kocide 2000, Nordox 75 WG, Olajos rézkén, Kumulus S, Rézkén, Rézoxiklorid) and another 6 fungicides (Score 25 EC, Efuzin 500 SC, Systane, Folicur Solo, Zato Plusz, Rovral) approved in organic and integrated production systems, respectively, were tested against brown rot of sour cherry. The three isolates showed differences in sensitivity to fungicides. Fungicides (with active ingredients of copper and sulphur) applied in organic production showed relatively high percent growth capacity of M. laxa. Rézkén and Kocide 2000 showed the highest and Kumilus S the lowest efficacy against brown rot. Fungicides applied in integrated production showed relatively low percent growth capacity of M. laxa. Score 25 EC showed the lowest and Rovral and Folicur solso the highest efficacy against M. laxa.

• Preliminary results on salicylic acid treatment on brown rot caused by Monilinia laxa on Jumbo Cot fruit, Prunus armeniaca L.

  37-39.

  A. Ezzat

  Z. Szabó

  J. Nyéki

  I. J. Holb

  Views:

  381

  The effect of salicylic acid on reducing brown rot caused by Monilinia laxa infection in postharvest apricot fruit Prunus armeniaca L. Freshly harvest Jumpo Cot fruit were treated with water as control treatment and other group treated with salicylic acid 2 Mm as induced resistance treatment, Fruits were infected by M. laxa (1 × 10-3spores ml-1) and incubated at 25 oC for 2, 4 and 6 days. Treatment fruits with salicylic acid resulted in direct effect on mycelial growth as in the salicylic acid treatment the growth reached to 45% after 6 days of incubation while in the control treatment it reached to 100%.

• Susceptibility of sour cherry cultivars to isolates of Monilia laxa (Ehrenbergh) Saccardo et Voglino

  83-87.

  Sz. Sződi

  Zs. Rozsnyay

  E. Rózsa

  Gy. Túróczi

  Views:

  331

  In this study, the susceptibility of 7 commercially important sour cherry cultivars to Monilinia laxa was studied. Artificial inoculation was made with M. laxa isolates, which were isolated from different woody plants. Artificial inoculation was prepared in the laboratory and in the field. In laboratory, flowers of sour cherries while in the field, the two-year old twigs were inoculated in 2006 and 2007. According to results of stigmata inoculation, there were infection ability differences among the isolates originated from five different stone fruit host. Cultivars could be sorted into two susceptibility groups. In the field, twig inoculation in 2007 was made at blossom period and in 2007 at harvest. Seven sour cherry cultivars were inoculated with 8-day-old mycelial culture of M. laxa originated from sour cherry and almond. The agressivity and pathogenicity of the two isolates were measured by the degree of floem death: Results showed that year and phenological stage considerably influenced the degree of symptoms caused by the fungus. After artificial inoculation, tissue death progression was studied by fluorescent microscope. According to results, sour cherry cultivars were sorted into disease susceptibility groups. Susceptibility orders were identical to results on stigmata inoculation.

• Brown rot blossom blight and fruit rot of apricot in Hungary

  139-141.

  G. Drén

  Z. Szabó

  M. Soltész

  J. Nyéki

  I. J. Holb

  Views:

  345

  The aim of our two-year study was to assess incidence of brown rot blossom blight and fruit rot caused by Monilinia laxa in 2003 and 2004. Assessments of incidence were made on cv. Bergeron (susceptible to brown rot) in a flatland and a hilly growing area (at Cegléd and Gönc, respectively). In both locations, plant protection was performed according to the integrated fruit production guidelines and small untreated plots were set up for each cultivar in both years. In 2003, when weather conditions were dry and hot, brown rot incidence was low (less than 10%) on both blossoms and fruits. Monilinia laxa did not cause significantly different blossom blight and fruit rot at the hilly (Gönc) area compared to the flatland, not even in untreated plots. However, in 2004, when spring and summer weather conditions were wet and cold, Incidence reached 95% for blossom blight and 33% for fruit rot in the untreated plots. Blossom blight incidence was 1.5-2 times higher in the flatland area compared to the hilly growing area. During the blooming period of apricot, two (at flower bud stage and at full bloom) and three (at flower bud stage, at full bloom and at petal fall) fungicide applications were necessary for the successful control at Gönc and Cegléd, respectively. The difference between the two orchards was due to the fact that blooming started one week later in the hilly region (at Gone) than in the flatland region (at Cegléd), therefore, the critical weather period coincided with blooming in the orchard in the hilly region only partially. Fruit rot incidence was similar in both regions as the amount and distribution of rainfall were similar during the fruit ripening period.

• The brown rot fungi of fruit crops (Monilinia spp.): II. Important features of their epidemiology (Review paper)

  17-33.

  I. J. Holb

  Views:

  246

  Plant disease epidemiology provides the key to both a better understanding of the nature of a disease and the most effective approach to disease control. Brown rot fungi (Monilinia spp.) cause mainly fruit rot, blossom blight and stem canker which results in considerable yield losses both in the field and in the storage place. In order to provide a better disease control strategy, all aspects of brown rot fungi epidemiology are discribed and discussed in the second part of this review. The general disease cycle of Monilinia fructigena„M. laxa, M. fructicola and Monilia polystroma is described. After such environmental and biological factors are presented which influence the development of hyphae, mycelium, conidia, stroma and apothecial formation. Factors affecting the ability of brown rot fungi to survive are also demonstrated. Then spatio-temporal dynamics of brown rot fungi are discussed. In the last two parts, the epidemiology of brown rot fungi was related to disease warning models and some aspects of disease management.

• The brown rot fungi of fruit crops (Monilinia spp.): III. Important features of disease management (Review paper)

  31-49.

  I. J. Holb

  Views:

  335

  In the third part of this review, important features of disease management are summarised for brown rot fungi of fruit crops (Monilinia fructigena, Monilinia laxa, Monilinia fructicola and Monilia polystroma). Several methods of brown rot disease management practices were collected and interpreted in five main chapters. In these chapters, details are given about the legislative control measures, the cultural, physical, biological and chemical control methods. Chemical control is divided into two parts: pre-harvest and post-harvest chemical control. In addition, host resistance and fungicide resistance statuses are also included in this part of the review. Finally, future aspects of brown rot disease control are discussed.

• Incidence of brown rot blossom blight caused by Monilinia laxa in organic sour cherry production in Hungary

  133-135.

  I. J. Holb

  Views:

  184

  Brown rot blossom blight incidence was evaluated on two sour cherry cultivars (Kántorjánosi, Újfehértói fürtös) in an organic sour cherry orchard in Hungary in 2003 and 2004. Trees were grown according to the organic fruit production guidelines. Blossom blight incidence was similar in both cultivars in both years. In 2003, blossom blight incidences were low even in the untreated plots (less than 15 %). In 2004, brown rot blossom blight incidence reached almost 30 % in the untreated plots. Blossom blight incidence was significantly lower in the conventionally treated plots in both cultivars.

• Yield loss caused by fruit rot fungi on sweet cherry in Kyustendil region, Bulgaria

  49-52.

  B. Borovinova

  Views:

  150

  The aim of the study was to determine the incidence of fruit rot caused by several fungal pathogens from 1999 to 2003. The study was conducted in three sweet cherry orchards at the Institute of Agriculture (Kyustendil, Bulgaria). One copper containing fungicide was applied in late autumn and early spring. During the growing seasons, 2-5 sprays were applied against fungal diseases. Trees were not sprayed specifically against fruit rot during the growing season, with the exception of 1999, when a spray of myclobutanil was applied after a long rainy period during the maturity of fruits. In one orchard, two nitrogen fertilization treatments were also prepared. In treatment 1, trees were fertilized with ammonium-nitrate 10 g/m² and in the other treatments trees were not. Incidence of the five most important fruit rot pathogens, Monilinia fructigena, M. laxa, Botritys cinerea, Alternaria alternata and Rhizopus stolonifer was assessed in all orchards. The most severe yield loss (14.80 %) was measured in 1999, when weather conditions were the most favourable for fruit rot development. In this year, brown rots (M. fructigena and M. laxa) caused the highest damage (9.22 and 4.04 %, respectively) out of all assessed fruit rot pathogens. In all other years, yield loss was significantly lower than in 1999. In 2002, A. alternata caused the main fruit rot (4.46%) and all other fungi were less important, while in 2003, B. cinerea caused considerable yield loss (2.28 %) compared to all other fruit rot pathogens. Experiments on fertilization showed that nitrogen significantly increased fruit rot damage in 1999, 2001, 2002 and 2003. The effect of nitrogen fertilization was higher in years with rainy periods around harvest (1999 and 2002) compared to more dry years (2000 and 2001). Results were compared with similar studies and biological interpretations of the results are discussed.

• Disease warning models for brown rot fungi of fruit crops

  19-22.

  I. J. Holb

  Views:

  279

  In this review, disease warning models for brown rot fungi, including Monilinia fructigena, M. laxa and M. fructicola, were summarized. Few studies have been made to relate epidemiology and disease warning in brown rot infection caused by M. fructicola and M. laxa in order to predict infections or develop decision support models for fungicide applications during the growing season. More recently a disease warning model and a decision support system were also performed for M. fructigena for organic apple orchards. This review gives an overview on some details of the above disease warning models and decision support system.

• Possibilities of brown rot management in organic stone fruit production in Hungary

  87-91.

  I. J. Holb

  Views:

  339

  In this study, possibilities of environmentally-friendly plant protection against two brown rot species was summarized for organic stone fruit orchards. Symtomps of the two most important brown rot species (Monilinia fructigena (Aderh. & Ruhl.) Honey and Monilinia laxa (Aderh. & Ruhl.) Honey) were described and then cultivar susceptibility to brown rot was discussed. Several sustainable plant protection methods were selected and discussed in details such as mechanical, agrotehcnical, biological, and other control possibilities (elemental sulphur, lime sulphur and copper).

• Possibilities of blossom and twig blight management in organic stone fruit production

  103-105.

  I. J. Holb

  M. Fazekas

  P. Lakatos

  B. Balla

  J. M. Gáll

  Views:

  239

  In this study, possibilities of environmentally-benign plant protection against blossom and twig blight were summarized for organic stone fruit orchards. Symtomps of Monilinia laxa (Aderh. & Ruhl.) Honey) were described and then cultivar susceptibility to blossom and twig blight was discussed. Several sustainable plant protection methods were selected and discussed in details such as mechanical, agrotechnical, biological, and other non-chemical control possibilities (stone powders, plant extracts and restricted chemical materials).