Sorghum germination under PEG-induced drought stress

Abstract

The aim of this study was to investigate the effects of the increasing polyethylene glycol - PEG concentrations (2.5, 5.0, 7.5, 10.0, 12.5, 15.0, 17.5, 20.0, 22.5, 25.0, 27.5, and 30.0%) on germination and early seedling growth of grain sorghum genotypes NS Al74 x Re37/07 and NS Gold. The trial included distilled water as control where no significant differences between genotypes were observed for any of the examined parameters. The drought treatments starting from 10.0% PEG decreased germination energy and percentage, and the most discriminative treatment was 17.5%. The shoot growth parameters provided better differentiating between the genotypes than those of root growth. The discriminative treatments were in the range of 7.5-15.0% PEG. NS Al74 x Re37/07 was less affected by the PEG-imposed drought than NS Gold; however the comprehensive field study would be required to confirm the presumable drought tolerance of the hybrid.

Cilj rada je bio da se ispita efekat rastućih polietilen glikol - PEG koncentracija (2,5; 5,0; 7,5; 10,0; 12,5; 15,0; 17,5; 20,0; 22,5; 25,0; 27,5; 30,0%) na klijanje i rani porast klijanaca genotipova sirka za zrno NS A174 x Re37/07 i NS Gold. Ogled je uključivao destilovanu vodu kao kontrolu, gde za ispitivane parametre nisu uočene značajne razlike izmedu genotipova. Tretmani sušom počevši od 10,0% PEG-a su snizili energiju klijanja i klijavost, a najveće razlike među genotipovima su se ispoljile kod tretmana od 175%. Parametri rasta nadzemnog dela klijanca su omogućili bolju procenu tolerantnosti na sušu od parametara rasta korena. Kod tretmana u opsegu 7,5-15,0% PEG-a su se razlike među genotipovima u pogledu ranog porasta klijanaca ispoljile u najvećoj meri. Tretmani su u manjoj meri uticali na NS A174 x Re37/07 nego na NS Gold, međutim potrebno je izvesti poljski ogled da bi se potvrdila tolerantnost na sušu ovog hibrida.