English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Tools annual

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Tools monthly

Global: Zendy Plus monthly

Presents the access of premium content as premium feature

Premium Content

Global: Zendy Plus annual

Global: Zendy Free Plan

Apples are grown in the largest areas in the Northern Great Plain in Hungary with an average apple production of 550–600 thousand tonnes, which is the 5 largest in Europe (Gonda and Csihon, 2018). Areas where all the conditions are favorable and intensive plantations with a high plant number provide 40–45 t ha yield. Due to the continental climate, frost damage is frequent in autumn, spring and winter, and the occurrence of drought is significant in summer. Domestic plantations are able to produce an average yield of up to 30–40 t ha during these effects, (Gonda and Apáti, 2011). Apples have an average annual heat demand of 10–11 °C according to their agro-ecological needs and prefer acidic soils to pH 5.8–7.0 (Kállay, 2014). Apples are a water-demanding fruit species, requiring about 750–800 mm of precipitation/year. It is highest water demand is from the beginning of June to the end of August. The quality of the fruit and the safety of the crop can be endangered by intensive plantations even if the critical water supply lasts only a few days during this period (Petesné, 2008). The use of hail net an intensive plantation supplement can be very useful and economical (Szabó, 2016), since hail can cause a serious problem in apple cultivation, where even a small amount of ice can degrade the apple so that it can only be sold for juice production (Kadosa, 2010). Use of the hail net have some positive effects on a given stock, one of the most important of which is temperature, where it plays a role in reducing extreme fluctuations. Another advantage is the possibility of water-saving production since the wind speed decreases, so the amount of water evaporated by the trees will be reduced by 30–40% (Lakatos et al., 2011). The plant water potential is the chemical potential of a system or part of the system water, expressed in terms of pressure, relative to the chemical potential of pure water. The value of water potential is highest in soil and lowest in air, and gives a temporary value from soil to air in the plant under normal conditions (Ördög and Molnár, 2011). The value of water potential, due to environmental reasons, is a key variable in the functioning of plant life. The two basic factors that determine the value of water potential are the concentration of solutions and the value of hydrostatic pressure. The gradient of water pressure in xylem as well as negative pressure can be detected. Scholander (1965) constructed a thick-walled pressure chamber container in which the leaf or fold was sealed and pressurized into an opening, and the leaves were placed in a chamber to measure the pressure present in the leaf or fold. In a closed container, the pressure was increased until the plant sap appeared on the cut surface (Boyer, 1967; Teszlák, 2008; Bratek et al., 2013). The pressure that water exerts on the cut surface indicates how much stress the leaf is experiencing in the water supply. High pressure means high water and high tension which vary within species and breeds. The water potential value in plants and its measurement has recently received considerable attention as water potential indicates the need for water within the plant. High water potential values affect the physiological processes of the plant, including slowing down or total stopping of photosynthesis, which reduces plant growth and ultimately causes plant death. This value can serve as a guide for improving growth and yield. Its unit is expressed in megapascal (Mpa) (McDowell et al., 2008; Klein, 2014; Steppe, 2018). Since the effect of hail net on the water potential of apple canopy thus on the water balance of apple orchards is not well studied, we aimed to analyse the effect of the hail net on the water supply and balance of apple orchards based on measuring water potential of apple canopy and microclimate data.

Effect of hail net on the water potential of an apple orchard