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 we...re selected and discussed in details such as mechanical, agrotechnical, biological, and other non-chemical control possibilities (stone powders, plant extracts and restricted chemical materials).
Still a large amount of pesticides and spary applications are used in environmentally friendly fruit production systems; therefore, the aim of our study was first to test the in vitro effeicacy of some fungicides against a key apple disease (apple scab), and secondly to evaulate the effectiveness of reduced spray programmes against apple s...cab, powdery mildew and coding moth in integrated and organic apple orchards. 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 apple scab. Altogether four spray programmes were performed i) standard integrated: sprays followed by forecasting systems during the season, ii) reduced integrated: sprays followed by forecasting systems but only 75% of the spray numbers used during the season-long spray programme, iii) standard oragnic: sprays applied every 7–14 days during the season and iv) reduced organic: 60% of the spray numbers used during the season-long spray programme. In vitro results showed that fungicides (with active ingredients of copper and sulphur) applied in organic production showed relatively high percent growth capacity of the apple scab fungus. Rézkén showed the highest and Kumilus S the lowest efficacy against apple scab. Fungicides applied in integrated production showed relatively low percent growth capacity of the apple scab fungus. Score 25 EC showed the highest and Rovral the lowest efficacy against apple scab. Field study showed that reduced spray programmes did not increase significantly scab incidence in the integrated field. However, scab incidence increased significanly (above 30%) in the reduced spray programme for the organic orchard.Mildew incidence was low (below 5%) in both integrated and organic spray programmes. Mildew incidence on both shoots and fruits increased significanly in the reduced spray programme for the organic orchard. Incidence of codling moth damage was affected the most by standard vs. reduced spray programmes. Though incidence remained below 10% in the integrated plots, the incidence was significantly higher in the reduced spray programme compared to the standard programme. Similar results were obtained for organic spary programmes, but the incidence was 10 times higher and the differences among the two programmes were larger.,
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.
Some experience or details are introduced in connection with the nutrient uptake of micropropagated fruit trees in the different phase of the in vitro or ex vitro development. It can be stated, that the plants during the micropropagation procedure are overfed. Special careful nutrient supply is necessary during the acclimatiza...tion.
A useful method was improved to test and to evaluate the susceptibility of plants to fire blight and the virulence of E. amylovora strains. Six Hungarian strains from different host plants were tested on in vitro cultured apple rootstocks. Disease rating was used for the characterization of the process of disease development. ...The different strains had different capacity to cause disease, mainly in the first period of incubation. There were significant differences between the virulence of the strains.
In vitro plant material of clones (Q. robur) NL 100 A (adult) and NL 100 R (rejuvenated) received from Germany (A. Meier-Dinkel, 1995) were used in these experiments. WPM medium was used for the multiplication phase. Plantlets were subcultured monthly. Differences in quality and colour of the adult and rejuvenated cultures ind...uced us to follow and compare the changes of mineral- and chlorophyll content and dry weight during the propagation phase. Mineral and chlorophyll content as well as dry weight were measured weekly on three samples during the subculture period.
In the case of propagation rates we stated, they were similar around the year, but both clones had a high peak in April. Examining the cation-content, we detected that, the plantlets had a highest quantity of several elements during the 2nd and 3rd week of subculture. The iron content was the highest in the 1st week and after that it decreased continuously. It is supposed, that the content of iron is not enough in the media. The chlorophyll content of the rejuvenated clone was higher than that of the adult one.
In the rooting experiments it was stated that, after one-week cold treatment the rooting ability was the best.