Seed priming with polyethylene glycol improved drought tolerance of late sown wheat by enhanced gas exchange attributes

Y. Bani Khalaf, A. Aldahadha*, O. Migdadi and A. Alkaabnh

Department of Field Crops, National Agricultural Research Center (NARC),
PO Box 639, Baqa'a 19381, Jordan
*Correspondence: abdallah.aldahadha@narc.gov.jo

Abstract:

Late sowing, especially in regions prone to drought, significantly hampers crop growth and yield. To address this, field experiments were conducted during the winter of 2021–2022 at Maru and Mushaqar in Jordan to evaluate the effects of seed priming agents as seed priming with water (hydropriming), polyethylene glycol (osmopriming), calcium chloride (osmopriming), and a control (unprimed) on physiological, phenological and yield traits of durum wheat (umqais variety) under normal and late sowing conditions. Results showed that Maru exhibited superior performance in physiology, growth, and yield attributes compared to Mushaqar. While late sown wheat demonstrated better water use efficiency, normal sowing conditions generally favored other yield components. Seed priming by polyethylene glycol (PEG) improved relative water content, stomatal conductance, and grain yield compared to other treatments. Mushaqar recorded higher grain spike^-1 and spike m^-2 under normal sowing, while PEG-primed seeds produced significantly higher 1,000-grain weight and harvest index. Notably, PEG-primed seeds improved grain yield and 1,000-grain weight, suggesting enhanced drought resilience under late sowing conditions. The study concludes that seed priming, especially with PEG, effectively improves drought tolerance in late sown wheat by enhancing photosynthetic activity, chlorophyll content (SPAD), and water retention. The findings indicate that PEG seed priming can effectively mitigate the negative impacts of late sowing, supporting its use as a practical strategy for improving wheat performance in semi-arid environments.

Key words:

Development of stomatal conductance of maize under moderately hot, dry production conditions

A. Széles¹, É. Horváth¹*, D. Rácz¹, L. Dúzs¹, Cs. Bojtor¹ and L. Huzsvai²

¹University of Debrecen, Faculty of Agricultural and Food Sciences and Environmental
Management, Institute for Land Utilisation, Technology and Regional Development,
Böszörményi street 138, H-4032 Debrecen, Hungary
²University of Debrecen, Faculty of Economics and Business, Institute of Statistics and
Methodology, Böszörményi street 138, H-4032 Debrecen, Hungary
*Correspondence: szelesa@agr.unideb.hu

Abstract:

A field trial was conducted in Hungary, in a moderately warm, dry production area to determine the effect of single or split application of N-fertilizer on the stomatal conductance and grain yield of maize. The measurements were performed at on calcareous chernozem soil, in a strip field trial, under different weather conditions (2019 and 2020). In addition to the unfertilized control (A0) treatment, 60 (A60) and 120 kg N ha^-1 (A120) applied as spring basal fertilizer were followed by two top-dressing treatments in V6 (A90) and V12 (A120) phenophases with doses of +30 and +30 kg N ha^-1, respectively. Stomatal conductance measurements were taken at V6, V12 and R1 phenological phases. It was found that stomatal conductance showed a decreasing trend with advancing phenological phases in both years, with 43.9% and 32.1% (P < 0.001; P < 0.01) decreases by the R1 phase, respectively. Application of higher doses of N fertilizer increased stomatal conductance, with the exception of the R1 phenological phase, which showed a decrease compared to the A0 treatment. The decrease in 2019 was caused by a reduction of soil moisture. Although there was sufficient water in the soil in 2020, due to the intermittent water shortages caused by but the large leaf area and rapid transpiration of the plants resulted in the stomata to close. The best fertilisation strategy was A60 and A120 kg ha^-1 depending on the crop year. The study showed that the highest yield is obtained when the average stomatal conductance is around 250 mmol m^-2 s^-1 during the growing season.

Key words:

fertilization, maize, stomatal conductance