The aim our research was to develop effective methods for organic apple farming, based on the use of plant extracts to control the asexual reproduction of Venturia inaequalis. Plant extracts of artemisinin, chelidonine, thymol, and populin tested in vitro under laboratory conditions significantly slowed down the germination of V. inaequalis conidia. During a 2-year study under field conditions, the effect of 1% populin, an extract from black poplar buds, on apple scab was tested in parallel with synthetic fungicides and a nopesticide regime on Golden Delicious and Jonathan apples. Populin significantly reduced the number of scabbed leaves and fruits on Golden during the first year of the field evaluation compared to synthetic fungicides and had a similar effect as synthetic fungicides in the second year of application. The mean number of scabbed leaves on Jonathan was reduced significantly by both synthetic fungicide and populin applications in both years; however, while synthetic treatments did not reduce the number of scabbed fruits in the first year, populin significantly reduced the number of lesions on fruits. According to these results, we concluded that the severity of apple scab on commercial apple cultivars can be reduced using 1% populin plant extract as a cheap, alternative, and highly available method of reducing the conidial spores. The estimated costs of spraying populin per hector on apple plantations were much lower than costs for synthetic fungicides. Populin application may allow elimination or reduction of synthetic fungicide use and enable efficient organic apple farming.

During the study, the seeds of seven sweet basil cultivars were treated with 100 ppm solutions of gibberellic acid or ascorbic acid prior to a 14-day germination experiment. Values of the first day of germination, germination energy, germinability, mean time and rate of germination, and uncertainty and synchrony of germination were calculated. The results show that both of the substances altered the measured parameters, priming with gibberellic acid proving to be a more effective way to enhance the germination of basil seeds. Also, they revealed major differences among the germination parameters of the examined cultivars.

The tissue invasion can be achieved by active (direct penetration of epidermal surface) and passive economic losses caused by the pathogen exceeded $ 10 billion worldwide (Weiberg et al., 2013) and due to economic impathogen in the world (Dean et al., 2012). One of the strategies for B. cinerea management is the fungicide application,The most serious problem in the cyclamen production in B. cinerea, which turns up at the B. cinerea infection can damage blossoms, but without growers can choose between two solutions: avoid using pesbut save the plants even so this solution delays marketing.

Studies conducted in controlled environments showed that seed priming and foliar treatments with various bioactive substances can stimulate germination, uniform seedling emergence, photosynthesis, and nutrient uptake efficiency and can lead to increased productivity, crop stand, and quality. Only a few studies provide a comparative experimental outlook about the use of the bioactive substances in open-field cultivated canola. The aim of this study was to investigate the effects of seed priming and foliar treatment with ascorbate (AsA), cysteine (Cys), and triacontanol (Tria) on the growth and yield parameters of two canola cultivars rapeseed cultivars (“Factor” and “Hybrirock”) under open-field conditions for three growing seasons under temperate conditions from Central Transylvania. Plant growth and yield parameters were recorded at different plant development stages: in autumn (early vegetative period), in spring, and at harvest. Not all substances that have undergone laboratory testing were successful in the field. Seed priming with 10 ppm Cys and AsA had beneficial effects on the development of seedlings, whereas their foliar application enhanced the number of silique, seed yield, and the oil content of the studied canola cultivars. The effects of Tria were visible on the biometrics parameters only in autumn and spring, and also on the root parameters, but in some cases, 10 ppm Tria had no effect on plants, or even a negative effect could be observed on important parameters for agriculture such as estimated seed yield, seed yield/plant, and oil content. Optimizing treatment and application by determination of the lowest effective concentration, together with the frequency of treatments and persistence effects are crucial for cost-effectiveness.

The functional role of the insect pathogen fungus Metarhizium anisopliae strain NCAIM 362 against the white grub cockchafer (Melolontha melolontha) larvae and southern European marshland pyralid (Duponchelia fovealis) larvae in a sweet potato cultivation was tested under greenhouse conditions. As a positive control, the effect of the same strain of M. anisopliae were compared with the effect of the synthetic insecticide alpha-cypermethrin. According to the results, alpha-cypermethrin was more effective against both the Coleoptera and Lepidoptera larvae, a lower number of surviving individuals as well as less damaged tubers were detected after the chemical treatment, compared with M. anisopliae.