The response of garden pea cultivars to simulated drought

Abstract

This study aimed to estimate genetic variability among four pea cultivars and determine seed physiological quality and initial growth of garden pea (Pisum sativum L.) under drought stress. Seeds of the pea cultivars were subjected to water stress induced by polyethylene glycol PEG 6000 at three stress levels (0; -0.15; -0.49, and -1.03 MPa). The experiment was conducted under laboratory conditions, in a completely randomized design with four replications, to estimate germination energy, germination, abnormal seedlings, fresh and dry shoot and root biomass, and drought tolerance index. Drought stress significantly affected germination and the other traits, with the stress effects being proportional to the stress level applied. Findings point to the fact that the osmotic potential of -0.49 MPa might be the germination sensitivity threshold for pea cultivars. The pea cultivar C1 was the most tolerant, having the highest germination, fresh and dry shoot and root biomass, and DTI under severe drought stress. Further research on the assessment of physiological and biochemical responses to drought stress is needed to confirm the findings of the present study.

Cilj ove studije bio je da proceni genetsku varijabilnost četiri sorte graška i utvrdi fiziološki kvalitet semena i početni rast povrtarskog graška (Pisum sativum L.) u uslovima stresa suše. Seme sorti graška podvrgnuto je deficitu vode izazvanom polietilen-glikolom 6000 na tri nivoa stresa (0; -0,15; -0,49 i -1,03 MRa). Eksperiment je izveden u laboratorijskim uslovima, u potpuno slučajnom dizajnu sa četiri ponavljanja. Procenjena je energija klijanja, klijavost semena, atipični izdanci, sveža i suva biomasa nadzemnog dela izdanaka i korena i indeks tolerancije na sušu. Stres suše značajno je uticao na klijavost i druge osobine, a efekti stresa su bili proporcionalni izazvanom nivou stresa. Rezultati ukazuju na činjenicu da bi osmotski potencijal od -0,49 MRa mogao biti prag osetljivosti na klijavost sorti graška. Sorta graška C1 pokazala se kao najtolerantnija, imala je najveću klijavost, svežu i suvu biomasu korena i izdanaka i indeks tolerantnosti pod jakim stresom suše. Dalja istraživanja na temu procene fizioloških i biohemijskih odgovora na stres suše potrebna su da bi se potvrdili nalazi ove studije.