Mustikaaretiste (Vaccinium) produktiivsus ja viljade kvaliteet maheviljeluse tingimustes

Abstract

Ammendunud turbaväljadel mustikate mahedalt kasvatamine on osutunud sobivaks, sest turvas on mustika jaoks paraja happesuse ja kõrge orgaanilise aine sisaldusega. Eesti Maaülikoolis on mustika uurimisega tegeletud aastakümneid, sealhulgas on leitud meie kliimatingimustesse uusi sobivaid liike ja sorte. Poolkõrge mustikas (V. angustifolium x V. corymbosum) ’Northblue’ on tänu heale talvekindlusele, saagikusele ja suurele marjale üheks levinumaks sordiks Eesti tootmisistandikes. Uute sortide järgi on vajadus, et laiendada kohalikult kasvatatud värskete ja tervislike mustika marjade valikut ja kättesaadavust tarbijale. Katse eesmärgiks oli kahe ahtalehise mustika ja kuue poolkõrge mustika aretiste puhul välja selgitada saagikamad ja suurema bioaktiivsete ühendite sisaldusega aretised, mis sobiksid turbaistandikes kasvatamiseks. Katse on rajatud 2010. aastal üheaastaste mikropaljundatud taimedega ammendunud freesturbaväljale Eesmärkide saavutamiseks analüüsiti 2019. aastal Marjasoo talu katseistandikus kasvanud 8 aretise vegetatiivseid ja biokeemilisi parameetreid. Töö hüpotees leidis kinnitust – aretised mõjutasid oluliselt taimede vegetatiivseid parameetreid, saagikust, vilja massi ja biokeemilist koostist. Katses olnud aretised olid saavutanud täiskasvufaasile omased kasvuparameetrid ja sarnanesid eelnevate aastate tulemustega. Mustikate tervislikkus ja antioksüdantsus seisneb nende kõrge fenoolsete ühendite, eelkõige antotsüaanide sisalduses. Analüüsitud aretiste fenoolsete ühendite sisaldus varieerus vahemikus 174-232 mg/100g ja antotsüaanide sisaldus 102-204 mg/100g. Biokeemiliste näitajate poolest oli väärtuslik poolkõrge mustika aretis 8//04, mille suurtes viljades oli kõige kõrgem fenoolsete ühendite ja antotsüaanide sisaldus. Katses olnud poolkõrge mustika aretis 23//00 oli kõrge saagikusega, mis on sarnane sordile ’Northblue’. Vaatamata ebasoodsale ilmastikutingimustele on 23//00 igal katseaastal andnud arvestatavat saaki. Antud aretis on väärtuslik oma kõrge saagikuse ja talvekindluse poolest ning sobib turvasmullal kasvatamiseks tootmise eesmärgil.

Abandoned peatlands have proven to be suitable for growing blueberries organically, because of the suitable acidity and high organic matter in peat. The blueberry research has been carried out for decades in the Estonian University of Life Sciences, and as a result, many new species and cultivars have proven to be suitable for growing in the northern climatic conditions. Half-highbush blueberry (Vaccinium angustifolium x V. corymbosum) cultivar ’Northblue’ has been recommended for the blueberry production due to its winter hardiness, high yield and big fruit size. However, there is a growing need for new health promoting blueberry cultivars that are rich in bioactive compounds and have a high yield to extend the availability and diversity of locally grown fresh blueberries for consumers and for the producers. The aim of the present thesis was to determine Vaccinium selections with high productivity and biochemical compound content. The experiment was established in 2010 with one–year–old micropropagated seedling selections. In order to achieve the aim of this thesis, data was collected in 2019 at Marjasoo farm from two lowbush blueberries (V. angustifolium) and six half-highbush blueberries (V. angustifolium x V. corymbosum) grown in organic peatland conditions. The hypothesis was confirmed – selections had an effect on the vegetative parameters, productivity, fruit mass and biochemical composition. All selections had achieved mature stage parameters, which were similar to the earlier studies. Health-beneficial effect of blueberry is related mainly to its high anthocyanin and total phenolic content. The total phenolic content in the selections was ranged from 174 to 232 mg/100 g and anthocyanin content ranged from 102 to 204 mg/100 g, which were both similar compared to cultivar ‘Northblue’. Selection named 8//04 demonstrated highest total phenolic and anthocyanin content, furthermore it had big berries. Lowbush blueberry selection 10//00 had high yield, with high total phenolic and anthocyanin content, while the organic acids content was low. The highest yield was produced by 23//00, which was similar to half-highbush blueberry cultivar ‘Northblue’ average yield. Selection 23//00 have shown stable yield performance during the experimental years despite of the night frost in spring and the harsh winters. Therefore, this selection is valuable for its high yield and winter hardiness and could be recommended for peatland production.