Effects of copper citrate as a defoliant in nursery fruit stock production

Abstract

The effects of copper citrate on defoliation of one year old fruit stocks in a nursery are presented in this paper. The investigation aimed to evaluate the defoliation efficacy of copper citrate as a new formulation, compared with other compounds recommended for that purpose. Field trials were conducted in the region of Trstenik, a center of nursery production in Serbia in 2016 and 2017. Two years of investigation showed that copper citrate could be used as an efficient compound for defoliation in nursery production. A stronger defoliation effect was observed on plum stocks, compared to apple stocks. Better results were achieved with the highest concentration of copper citrate (2%), while the effectiveness decreased with lower concentrations (0.5%, 1.0% and 1.5%). Defoliation degree on nursery apple stocks after treatment with 2.0% concentration of copper citrate varied from 80.6% to 95.6%, while it reached 100% on plum stocks.

U radu su prikazani efekti defolijacije sadnica jabuke i šljive, primenom različitih koncentarcija bakar citrata, kao nove formulacije, i standardnih preparata koji se koriste u ove svrhe (bordovska čorba, urea). Ogledi su sprovedeni u regionu Trstenika (Ljubava i Milutovac), koji je centar rasadničke proizvodnje u Srbiji. Tretiranja su obavljena tokom 2016. i 2017. godine. Na osnovu dobijenih rezultata zaključeno je da bakar citrat pokazuje visok potencijal za upotrebu u svrhu defolijacije sadnica jabuke i šljive. Korišćene koncentracije ovog jedinjenja su pokazale veću efikasnost u primeni na sadnicama šljive nego na sadnicama jabuke. Najbolji rezultati u oba ogleda su zabeleženi sa maksimalno primenjenom koncentracijom (2%), dok efekat defolijacije na sadnicama jabuke opada sa smanjenjem koncentracije. Stepen defolijacije jabuke primenom bakar citrata u koncentraciji od 2% kretao se od 80,6% do 95,6%, a kod šljive čak 100%. Potvrđeno je i da uspešna defolijacija sadnica jabuke i šljive značajno zavisi od vremena aplikacije kao i meteoroloških uslova.