BIONÆR-Bionæringsprogram

The horticultural sector is a small but important part of agriculture in the Nordic and Baltic countries. However, the self-sufficiency level of fruits and berries is low in the region; approximately 10% in Estonia and up to 30% in some of the other countries. One of the priorities of rural development plans is to increase local horticultural production, in accordance with the goals set by European Green Deal, which focuses on reducing the environmental footprint. Apple, strawberry, and blackcurrants are the most important horticultural crops for the region are therefore targeted in InNoBaHort. The first objective of the project is to decrease the use of applied fertilizers by introducing a novel energy dispersive X-ray fluorescence technique in parallel with plant sap analyses. Of 82 strawberry leaf samples collected from commercial strawberry plantations in Estonia, N content in 38% was above optimal, 60% of the samples had recommended N level, and only 2% were N-deficient. Zn- and Ca- deficiencies were most common in strawberry fields, and these deficiencies can be avoided by using foliar fertilization. In the first year of experiments in Estonia, different fertilization levels did not have a significant effect on average fruit size but affected taste-related parameters of strawberry fruit. Developing and introducing disease forecasting models and low-risk biological alternatives is the foundation for the second objective, with an ultimate aim to reduce the use of synthetic fungicides in horticultural crops. The main attention is on developing new forecasting systems for European canker (Neonectria ditissima) in apple and Mycosphaerella leaf spot (Mycosphaerella ribis) in black currants. Data from Norway showed that ascospores of N. ditissima may be released year-round, with the highest numbers in May-June. The data were analyzed using traditional and machine learning models, and temperature and number of hours since rain (= 0.2 mm) were the most significant factors contributing to ascospore release. In Finland, data already acquired from spore trapping of N. ditissima were organized and shared within the WP2 group. Evaluation of five existing prediction models for N. ditissima was initiated. By using a set of data from previous work in Norway, temperature and wetness-based models were made for maturation and dissemination of both ascospores and conidia of M. ribis. For apple scab and grey mould of strawberry, the Norwegian team transfered knowledge from existing forecasting systems to Estonia and Lithuania through seminars for the fruit and berry industry in the two countries. The antifungal effect of different plant extracts on grey mould in strawberry is being evaluated in Lithuania. A questionnaire about the use of alternative plant protection products was carried out. The main message from the growers was that there is a lack of alternative plant protection products, and sometimes their efficiency is lower than for chemical products. The preliminary experimental results showed that low-risk biological products based on bacteria and plant extracts had a perspective to serve as alternative biological products for Botrytis fruit rot control in strawberry. The third objective of the project is to make a step forward in breeding of new apple cultivars with high levels of resistance to European canker. Different resistance components in old and new cultivars and promising breeding selections are being evaluated. There will be screening of Estonian, Norwegian, and Swedish apple cultivars, with an emphasis on Estonian germplasm, which has not previously been evaluated for canker susceptibility. In Sweden, a useful insight in two different inoculation methods for testing of apple material for resistance to N. ditissima was achieved. Furthermore, new knowledge on development of fruiting bodies (perithecia) of the pathogen under Swedish conditions was obtained. This knowledge is important to understand the epidemiology of N. ditissima.

Apple, strawberry, and blackcurrants are the most important horticultural crops for the Nordic-Baltic region and will therefore be targeted in InNoBaHort. The first objective of the project is to decrease the use of applied fertilizers by introducing a novel energy dispersive X-ray fluorescence technique in parallel with plant sap analyses. By detecting exact nutrient needs, we anticipate achieving a 30% reduction in nitrogen use per hectare in strawberry. Developing and introducing disease forecasting models and low-risk biological alternatives will be the foundation for the second objective, to decrease the number of synthetic fungicide sprays in horticultural crops. The main attention will be on developing new forecasting systems for European canker in apple and Mycosphaerella leaf spot in black currants. For apple scab and grey mould of strawberry, the Norwegian team will transfer knowledge from existing forecasting systems to Estonia and Lithuania. The antifungal effect of different plant extracts on grey mould in strawberry will be evaluated in Lithuania. The third objective of the project is to make a quantum loop in breeding of new apple cultivars with high levels of resistance to canker. Available chemical or biological measures against European canker are not sufficiently effective, and more use of resistant cultivars would significantly improve growers’ economy. Different resistance components in old and new cultivars and promising breeding selections will be evaluated. There will be screening of Swedish, Norwegian, and Estonian apple cultivars, with an emphasis on Estonian germplasm, which has not been evaluated for canker susceptibility.