Wheat Under Warmer Nights: Shifting of Sowing Dates for Managing Impacts of Thermal Stress

Roshan Subedi (), Mani Naiker, Yash Chauhan, S. V. Krishna Jagadish and Surya P. Bhattarai
Additional contact information
Roshan Subedi: Institute of Future Farming Systems, School of Health, Medical and Applied Sciences, Central Queensland University, Rockhampton, QLD 4701, Australia
Mani Naiker: Institute of Future Farming Systems, School of Health, Medical and Applied Sciences, Central Queensland University, Rockhampton, QLD 4701, Australia
Yash Chauhan: Department of Primary Industries, Kingaroy, QLD 4610, Australia
S. V. Krishna Jagadish: Department of Plant and Soil Science, Texas Tech University, Lubbock, TX 79409, USA
Surya P. Bhattarai: Institute of Future Farming Systems, School of Health, Medical and Applied Sciences, Central Queensland University, Rockhampton, QLD 4701, Australia

Agriculture, 2025, vol. 15, issue 15, 1-22

Abstract: High nighttime temperature (HNT) due to asymmetric diurnal warming threatens wheat productivity. This study evaluated the effect of HNT on wheat phenology, physiology, and yield through field and controlled environment experiments in Central Queensland, Australia. Two wheat genotypes, Faraday and AVT#6, were assessed under three sowing dates—1 May (Early), 15 June (Mid), and 1 August (Late)—within the recommended sowing window for the region. In a parallel growth chamber study, the plants were exposed to two nighttime temperature regimes, of 15 °C (normal) and 20 °C (high), with consistent daytime conditions from booting to maturity. Late sowing resulted in shortened vegetative growth and grain filling periods and increased exposure to HNT during the reproductive phase. This resulted in elevated floret sterility, lower grain weight, and up to 40% yield loss. AVT#6 exhibited greater sensitivity to HNT despite maturing earlier. Leaf gas exchange analysis revealed increased nighttime respiration (Rn) and reduced assimilation (A), resulting in higher Rn/A ratio for late-sown crops. The results from controlled environment chambers resembled trends of the field experiment, producing lower grain yield and biomass under HNT. Cumulative nighttime hours above 20 °C correlated more strongly with yield losses than daytime heat. These findings highlight the need for HNT-tolerant genotypes and optimized sowing schedules under future climate scenarios.

Keywords: grain filling period; high nighttime temperature; phenology; respiration to photosynthesis (Rn/A) ratio; wheat (search for similar items in EconPapers)
JEL-codes: Q1 Q10 Q11 Q12 Q13 Q14 Q15 Q16 Q17 Q18 (search for similar items in EconPapers)
Date: 2025
References: Add references at CitEc
Citations:

Downloads: (external link)
https://www.mdpi.com/2077-0472/15/15/1687/pdf (application/pdf)
https://www.mdpi.com/2077-0472/15/15/1687/ (text/html)

Related works:
This item may be available elsewhere in EconPapers: Search for items with the same title.

Export reference: BibTeX RIS (EndNote, ProCite, RefMan) HTML/Text

Persistent link: https://EconPapers.repec.org/RePEc:gam:jagris:v:15:y:2025:i:15:p:1687-:d:1717968

Access Statistics for this article

Agriculture is currently edited by Ms. Leda Xuan

More articles in Agriculture from MDPI
Bibliographic data for series maintained by MDPI Indexing Manager ().