Allelopathic effect of princess tree (Paulownica tomentosa (Thunb.) Steud.) on germination and growth of cabbage

Abstract

Cilj rada bio je utvrditi alelopatski utjecaj lista carske paulovnije (Paulownia tomentosa (Thunb.) Steud.) na klijavost sjemena i rast klijanaca kupusa. Provedena su dva pokusa: utjecaj vodenih ekstrakata carske paulovnije u Petrijevim zdjelicama, te utjecaj biljnih ostataka carske paulovnije u posudama s tlom. Istražen je učinak različitih koncentracija i doza na klijavost odnosno nicanje sjemena, duljinu korijena i izdanka, te svježu i suhu masu klijanaca kupusa. Rezultati su pokazali pozitivni i negativni alelopatski utjecaj. U pokusima u Petrijevim zdjelicama negativan utjecaj zabilježen je u gotovo svim tretmanima, a posebice s vodenim ekstrakatom najviše koncentracije koji je djelovao potpuno inhibitorno (100%) na sve mjerene parametre. Biljni ostaci u pokusu s tlom u dozi od 10 g/kg nisu pokazali statistički značajan utjecaj na mjerene parametre, izuzev na svježu masu klijanaca kupusa koja je bila povećana za 17,6%. Viša doza od 20 g/kg statistički je značajno inhibirala duljinu izdanka, te svježu i suhu masu klijanaca kupusa.The aim of the study was to determine the allelopathic effect princess tree (Paulownia tomentosa (Thunb.) Steud.) leaves on seed germination and growth of cabbage seedlings. Two experiments were conducted: the effect of princess tree water extracts in Petri dishes, and the effect princess tree plant residues in pots with soil. The effect of different concentrations and doses on seed germination and emergence, length of roots and shoots, and fresh and dry weight of cabbage seedlings were investigated. The results showed both positive and negative allelopathic effect. In experiments in Petri dishes, a negative effect was observed in almost all treatments, in particular with water extract in the highest concentration, which showed a complete inhibitory effect (100%) on all measured parameters. Plant residues in pot experiment in 10 g/kg dosage did not show statistically significant effect on measured parameters, except for fresh weight of cabbage seedlings, which was increased by 17.6%. A higher dose of 20 g/kg showed statistically significant inhibition of shoot length, fresh and dry weight of cabbage seedlings