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• Disease incidence of Monilinia fructigena coupled with codling moth damage and mechanical injury in an organic apple orchard

  55-57.

  I. J. Holb

  Views:

  210

  In a two-year-study, disease incidence of Monilinia fructigena were quatified and the importance of certain fruit wounding agents was determined. The first infected fruits were observed at the beginning of August in 2011 and 2012. Disease development was continuous until fruit harvest in both years. Pre-harvest yield loss caused by M. fructigena amounted on average 26.3% in 2011 and 40.4% in 2012 by fruit harvest. All infected fruits were injured mainly by mechanical injury factors and codling moth (Cydia pomonella). In this study, the most important wounding agents were codling moth and mechanical injury factors in organic apple orchards. In both years, our results showed that 65-75% of the infected fruits were damaged by codling moth in organic apple production. Moreover, 5-15% of the infected fruits were mechanically injured in the two years. Our results indicated that most of the damaged fruits fell on the orchard floor before harvest and they became an important secondary inoculum source of M. fructigena. Biological and practical implications of the results are discussed.

• Preliminary study on micro area based spatial distribution of Monilinia fructigena in an organic apple orchard

  19-21.

  I. J. Holb

  A. Rózsa

  F. Abonyi

  Views:

  185

  In this study, we aimed to report a preliminary study on micro area based spatial distribution of Monilinia fructigena in an organic apple orchard. Results showed that number of symptomatic fruit ranged between 22 and 42 in 2013 and between 25 and 35 in 2014. Number of asymptomatic fruit ranged between 111 and 187 in 2013 and between 119 and 167 in 2014. Disease incidence of fruit ranged between 19.7 and 23.2% in 2013 and between 19.1 and 26.5% in 2014. Disease aggregation index ranged between 0.111 and 0.335 in 2013 and between 123 and 401 in 2014. Three of the four trees showed significant within canopy aggregation of disease for fruit brown rot symptoms in both years. However, the remaining one tree exhibited random patterns during both years. Disease aggregation indicated a disease spread by fruit-to-fruit contact and/or an aggregated
  pattern of insect damage.

• Analyses of temporal dynamics of brown rot development on fruit in organic apple production

  97-100.

  I. J. Holb

  Views:

  170

  In a two-year study, yield loss and temporal dynamics of brown rot development caused by Monilinia fructigena (Aderh. & Ruhl.) Honey were quantified and analysed in two organic apple orchards (Debrecen—Pallag and Debrecen—Józsa). The first infected fruits were observed at the beginning of August in both years and both locations, except for one occasion when the first infected fruit was found at the end of July. Temporal disease development was continuous up to harvest time in both years and locations. In the two years, pre-harvest yield loss on the trees amounted between 8.9% and 9.3% at Debrecen-Pallag and between 9.7% and 10.8% at Debrecen—Jozsa by fruit harvest. Incidence of infected fruits on the orchard floor ranged from 32.4% to 43.2% and from 53.3% to 61.9%, at Debrecen—Pallag and Debrecen—Józsa, respectively, by fruit harvest. Analyses of temporal disease progress showed that the best-fitted mathematical function was the power function in both orchards and years. Both parameters of the power function clearly demonstrated that incidence of brown rot on fruit increased faster on the orchard floor than on the tree. Moreover, the disease increase was faster at Debrecen—Józsa in most cases than at Debrecen—Pallag. Our results indicated that the strategy of disease management, the ripeness of the fruit and the presence of a wounding agent played an important role in the yield loss and in the temporal development of fruit disease incidence caused by M. fructigena in organic apple orchards. Biological and practical implications of the results are discussed.

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

  31-49.

  I. J. Holb

  Views:

  292

  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.

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

  49-52.

  B. Borovinova

  Views:

  121

  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:

  219

  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.

• Effect of three storage methods on fruit decay and brown rot of apple

  55-57.

  B. Balla

  I. J. Holb

  Views:

  533

  The aim of our two-year study was to evaluate fruit decay and Monilinia fruit rot in three controlled atmospheres (CA), ultra-low oxygen (ULO) and traditional storage methods on apples for a duration of several months storage period. Four phytopathological treatments were studied under each storage condition: 1) 48 healthy fruit per unit, 2) 48 injured fruit per unit, 3) 47 healthy fruit and 1 brown rotted fruit per unit, and 4) 47 injured fruit and 1 brown rotted fruit per unit. Our results clearly demonstrated that fruit loss during storage is highly influenced by storage conditions and health status of the stored fruits. In the 2005 experiment, the lowest and largest fruit decay occurred under the ULO and traditional storage conditions, respectively (Table 1). The fruit decay was significantly different for the different storage methods. Fruit decay was fully suppressed in ULO storage except in the treatments of injured and injured + 1 brown rotted apple. Under CA and traditional storage conditions, when healthy fruit was stored, fruit decay was significantly lower compared with injured fruit including 1 brown rotted fruits. However, half of the fruit decay was caused by M. fructigena in CA store irrespective to phytopathogenic treatments. In 2006, results were not so consistent on cv. Idared but were not essentially different from the 2005 experiments.

• Epidemiology of brown rot on two apple cultivars in an organic apple orchard

  49-52.

  I. J. Holb

  J. Gáll

  Views:

  164

  In a two-year-study, the temporal development of brown rot (Monilinia fructigena) on fruits was analysed in an organic apple orchard on an early (Prima) and one late (Idared) maturing cultivars at Debrecen-Józsa in Hungary. Out of five mathematical functions (linear, exponential, three-parameter logistic, Gompertz, Bertalanffy-Mitscherlich), the three-parameter logistic function gave the best fit to brown rot incidence of all cultivars in both years. Disease progress started at the end of June for cv. Prima and at the end of July for cv. Idared, then disease increased continuously from 6-8 weeks up to harvest in all cultivars. Descriptive disease variates derived from the three-parameter logistic function were used to analyse disease progress. These were: Yf, the final disease incidence; Y55, fruit incidence at day 55; Y95, fruit incidence at day 95; b and q, the relative and the absolute rate of disease progress, respectively; T1.5, the time when disease incidence reaches 1.5 %; M, the inflection point and AUDPC, area under disease progress curve. Descriptive disease variates were significantly different (P<0.05) for cv. Prima compared to cv. Idared, except for the relative and absolute rate of disease increase, b and q, respectively. The largest differences among cultivars were in the values of the AUDPC. Disease progress curves and descriptive disease variates were presented and the practical implications of the results were discussed.

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

  87-91.

  I. J. Holb

  Views:

  283

  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).