Effects of drought stress on germination and seedling growth of different field pea varieties

Abstract

Germination and seedling growth of seven genotypes of field pea (Pisum sativum L.) were studied in PEG-6000 solution having osmotic potentials -0.1 and -0.2 MPa. A study was undertaken to evaluate the influence of different osmotic potentials (MPa) on seed germination percentage (GP) and mean germination time (MGT). Results show that the percentage of germination decreased with a decrease in osmotic potential, while mean germination time increased. Variety Javor is much more sensitive than the other varieties at all levels of osmotic stress. By contrast, the lowest sensitivity of germination and MGT was found in varieties Mraz and Trezor. Seed germination tests at -0.1 to -0.2 MPa have the potential to be used as tests in field pea. Osmotic stress exposure and its duration significantly affected the growth of seedlings (shoot and root) and the accumulation of biomass, while its effect was more prominent on the growth of the shoot than on root growth, which was also confirmed by the root tolerance index.

U radu je proučavano klijanje i porast ponika sedam genotipova stočnog graška (Pisum sativum L.) u rastvoru PEG-6000 sa vrednostima osmotskih potencijala od -0,1 i -0,2 MPa. Ispitivanje je izvršeno kako bi se utvrdio uticaj različitih osmotskih potencijala (MPa) na procenat klijavosti semena (GP) i prosečno vreme klijanja (MGT). Rezultati pokazuju da se procenat klijavosti smanjivao uporedo sa smanjenjem osmotskog potencijala, dok se prosečno vreme klijanja povećavalo. Sorta „Javor” mnogo je osetljivija od ostalih sorti pri svim nivoima osmotskog stresa. Suprotno tome, najmanji uticaj na klijanje i MGT utvrđen je kod sorti „Mraz” i „Trezor”. Određivanje klijavosti semena u rastvorima PEG od -0,1 do -0,2 MPa može se koristiti za testiranje stočnog graška. Izloženost osmotskom stresu i njegovo trajanje značajno su uticali na rast ponika (izdanak i koren) i akumulaciju biomase, pri čemu je njegov uticaj bio izraženiji na rast izdanka nego na rast korena, što je potvrdio i indeks tolerantnosti korena.