Germinacija nakon predtretmana semena i formiranje klijanaca kod kukuruza

Abstract

Tokom čuvanja, dolazi do propadanja semena i gubitka životne sposobnosti, energije i kvaliteta. S obzirom da se set međusobno povezanih biohemijskih promena, tj. aktivacija enzima, sinteza hormona–stimulatora rastenja, razgradnja inhibitora klijanja i reparacija ćelijskog oštećenja, javlja kao odgovor na izlaganje semena agensima predtretmana, eksperiment je imao za cilj procenu ekasnosti različitog prajminga semena na vigor i ukupnu performansu klijanaca kukuruza. Izvršena je evaluacija četiri sorte kukuruza čuvane 5 i 35 godina u srednjoročnim uslovima (t=4-5°C; RH=40-45%), standardnim testiranjem klijavosti na lter papiru (BP, 20⇔30°C, ISTA Rules) i cold testom. Poređenjem sa netretiranim semenom, u suboptimalnim uslovima cold testa je utvrđen pozitivan efekat primene predtretmana semena na klijanje, uključujući i energiju klijanja, kao i na smanjenje broja

mrtvih semena, naročito izražen kod dugo čuvanog semena. Ispitivanjem ranog

porasta klijanaca, samo u cold testu je evidentiran pozitivan uticaj predtretmanana

na rast

klijanaca dugo čuvanog semena. Međutim, kod semena kraćeg perioda čuvanja, utvrđeno je da je uticaj predtretmana na izduživanje klijanca uglavnom determinisan genotipom. Testiranjem na lter papiru semena i kraćeg i dugog perioda čuvanja, utvrđen je pozitivan efekat KNO predtretmana na svežu masu korena, odnosno pozitivan efekat H 2 3 S predtretmana na svežu masu celog klijanca. Oba predtretmana su uticala na porast suve mase korena samo kod dugo čuvanog semena, odnosno na porast suve mase izdanka semena kraćeg perioda čuvanja. Testiranjem u uslovima cold testa semena i kraćeg i dugog perioda čuvanja, utvrđeno je da su svi predtretmani doprineli porastu sveže i naročito suve mase klijanca.

During storage, seed deteriorates, loses viability and quality. Given that a set of interlinked biochemical changes (i.e. activation of enzymes, synthesis of growth-promoting substances, germination inhibitors’ metabolism and cell damage repair) occurs in response to seed exposure to priming stimuli, this experiment aimed at estimating the efficiency of different seed priming on vigour and overall maize seedlings performance. Four maize landraces kept for 5 and 35 years under cold storage–CS (t=4-5°C; RH=45-50%) were evaluated, using standard seed germination test on lter paper (BP, 20⇔30°C, ISTA Rules) and cold test. Compared

to unprimed seeds (control), in suboptimal conditions of cold test, positive effect

of seed priming on germination, including germination energy, as well as on the

reduction of the number of dead seeds, was determined, while being more pronounced in seeds of long CS lifespan. In addition, a positive effect of seed priming

on early seedlings growth was recorded in seeds of long CS lifespan, being mainly

genotype-specific in seeds of short CS lifespan. For seeds of both the short and long CS lifespans, standard testing on filter paper showed that the halo–KNO3 and acidic–H2 S priming contributed to root, i.e. whole seedling fresh weight increase, respectively. Both seed priming contributed to root i.e. shoot dry weight in seeds of long i.e., short CS lifespan, respectively. Under conditions of cold test, in seeds of both the short and long CS lifespans, a positive impact of all evaluated seed priming on the seedlings fresh and especially dry weight was observed.