Reverzija inhibicije klijanja semena Paulownia tomentosa Steud. izazvane natrijum azidom

Abstract

The effect of some respiratory inhibitors on light-induced Paulownia tomentosa Steud. seed germination was studied. Millimolar solution of sodium azide was sufficient to completely prevent germination induced by a 5-min red light pulse. The inhibitory effect of azide was absent if seeds were rinsed before phytochrome activation by light. Sodium azide was effective only if present in the period of Pfr activity. The escape time from azide inhibition compared to the escape from far-red light action, was delayed for about 24 hours. When azide was applied after phytochrome activation, its effect depended on how long it was present in the incubation medium. The removal of azide allowed full restoration of germination by another red light pulse and the far-red escape time did not differ from the escape of untreated, i.e. water-imbibed seeds. Potassium cyanide alone did not produce any effect in light-stimulated germination of these seeds. However, it counteracted the inhibitory effect of azide in light-stimulated germination, if applied simultaneously at a concentration three times higher.

Ispitivan je efekat nekih inhibitora disanja na klijanje svetlošću indukovanih semena Paulownia tomentosa. Potpuna inhibicija klijanja, koje je indukovano sa 5 minuta crvene svetlosti, mogla je da se postigne već milimolarnim rastvorom natrijum azida. Inhibitorni efekat azida je izostajao ako se semena isperu pre aktiviranja fitohroma osvetljavanjem. Natrijum azid je bio efektivan samo ako je prisutan u semenima u periodu aktivnosti Pfr. Vreme za koje semena izbegavaju inhibitorni efekat azida je odloženo za oko 24 časa u poređenju sa istim za inhibitorno delovanje tamno crvene svetlosti. Kada se azid odstrani, dodatni puls crvene svetlosti dovodi do potpunog obnavljanja sposobnosti za maksimalno klijanje, a vreme za koje semena izbegavaju inhibitorni efekat crvene svetlosti se ne razlikuje od istog kod netretiranih semena, tj. onih koji su inbibirala u vodi. Kalijum cijanid nema nikakav uticaj na klijanje semena indukovanih svetlošću. Međutim, ako se kalijum cijanid primeni simultano sa natrijum azidom, u tri puta većoj koncentraciji, on sprečava inhibitorni efekat natrijum azida na klijanje indukovano svetlošću.