Maheviljeluses kasvataud aedmaasikate (Fragaria x ananassa Duch.) ’Allegro’ , ’Sonsation’ ja ’Polka’ saagikus ja viljade kahjustused avatud ja putukavõrguga kaitstud tunnelkasvuhoones

Abstract

Käesoleva bakalaureusetöö eesmärgiks oli välja selgitada maheviljeluses kasvatavate aedmaasikate ’Polka’, ’Sonsation’ ja ’Allegro’ saagikus ning viljade kahjustused avatud ja putukavõrguga kaitstud tunnelkasvuhoones. Katsed viidi läbi 2019. aasta suvel Tartumaal Haaslava vallas Aran PM OÜ kahes erinevas kiletunnelis. Ühe kiletunneli otsad ja küljed olid avatud ja teise kiletunneli otsad ning küljed kaeti putukavõrguga. Avatud tunnelis kasutati ripslase vastu siniseid liimpüüniseid. Taimed kasvasid mullas, musta kilemultšiga kaetud peenardes. Taimed olid istutatud kahes reas 28 cm vahedega. Tunneli tüübil ei olnud katsesortide turustatavale saagile statistiliselt olulist mõju, kuid tendentsina suurendas võrgu kasutamine kõikide katses olnud sortide saaki, näiteks ’Polka’ turustatav saak oli võrguga tunnelis 200 g/taim, avatud tunnelis aga 175g/taim. Sordi ’Sonsation’ puhul oli turustatav saak võrgutunnelis 237g/taim, avatud tunnelis 202g/taim. Ka sordi ’Allegro’ saak oli võrguga tunnelis tendentsina suurem. Katse keskmisena saadi võrgutunnelist statistiliselt oluliselt enam turustatavat saaki. Sorditi oli kõige saagikam ’Sonsation’ ja kõige väiksema saagiga sort ’Allegro’. Haiguste ja kahjurite poolt põhjustatud saagikaod olid sorditi erinevad. Sordi ’Sonsation’ puhul oli mõlemas tunnelis praakvilju 36%, ’Polka’ puhul avatud tunnelis 52%, võrgutunnelis 45% ja ’Allegro’ avatud tunnelis 25% ja võrgutunnelis 31%. Jahukastet esines rohkem võrgutunnelis (3-13%), vähem avatud tunnelis (1-4%). Avatud tunneli puhul esines ripslase kahjutusi rohkem (4-5%), võrgutunnelis vähem (1%). Sort ja tunneli tüüp mõlemad mõjutasid viljadel esinevaid kahjustusi ja turustatavat saaki. Antud uurimuses andis katse keskmisena kõige enam turustatavat saaki sort ’Sonsation’ ja kõige vähem ’Allegro’. Kuigi võrgutunnel suurendas katse keskmisena turustatavat saaki, olid võrgutunnelil ka omad puudused. Näiteks suurendas putukavõrgu kasutamine oluliselt jahukastesse nakatumist ’Sonsationi’ puhul. Ja majanduslikust aspektist vaadatuna ei tasu putukavõrgu kasutamine tunnelkasvuhoones maheviljeluses ennast ära, sest tõstab maasikakasvatusel tehtavaid kulutusi.

The aim of this study was to find out yield and fruit damages of organically grown strawberries ’Polka’, ’Sonsation and ’Allegro’ in open-sided and net-covered high tunnels. The experiments were performed in Tartumaa Haaslava county Aran PM OÜ in two different tunnels in summer 2019.. The sides and the doors of the open tunnel were opened when plants started flowering. In another tunnel we covered sides and doors with extra-fine insect net (mesh size 0.3 x 0.7 mm). In the open tunnel, blue glue traps were used to catch thrips. A++ frigoplants were planted in soil in two rows, beds were covered with black plastic mulch. Randomised block design was used with four replications per cultivar and 20 plants per replication. Plants were planted in 28 cm intervals. The tunnel type did not have a statistically significant effect on the marketable yield of the cultivars, but the use of the net tended to increase the yield. For example marketable yield of 'Polka' was 200 g/plant in the net-covered tunnel and 175g/plant in the open tunnel. For the ‘Sonsation’, the marketable yield in the net-covered tunnel was 237g/plant, in the open tunnel 202g/plant. The yield of the 'Allegro' was also higher in the net tunnel. As an average of the experiment, statistically significantly more marketable yield was obtained from the net-covered tunnel. In terms of cultivar, the most productive was 'Sonsation' and the cultivar with the lowest yield was 'Allegro'. Yield losses caused by diseases and pests varied by cultivar. In the case of the ’Sonsation’, 36% of the total yield had defects in both tunnels The marketable yield loss of ’Polka’ in the open tunnel was 52% and in the net tunnel 45%. ’Allegro’ had the highest percentage of marketable fruits: the amount of damaged fruits in open tunnel was 25% and in the net-covered tunnel 31%. Powdery mildew was more common in the net tunnel tunnel (damegd fruits ranged from 3 to 13%), less in the open tunnel (1-4%). In the case of an open tunnel, the incidence of thrips damage was higher (4-5%), than in the net-covered tunnel (1%). In this study, the highest marketable yield was obtained from ’Sonasation’ and the lowest from ’Allegro’. Although the net-covered tunnel increased the average marketable yield of strawberries, it also had its drawbacks. For example, the use of insect nets significantly increased powdery mildew infection in 'Sonsation'. From the economic point of view, the use of an insect net in organic farming in a tunnel greenhouse did not pay off, as it increased the costs of strawberry growing considerably.