Responses of Canola Cultivars to Application of Micronutrients upon Late-season Drought Stress

ABSTRACT

There are different climate classes in Iran where about 85% of the agricultural lands are located in arid and semi-arid regions. To mitigate or compensate effects of drought stress and increase crop fitting and yield, effects of micronutrient application have been studied by several researchers. Field experiments were conducted during the 2021–2022 and 2022–2023 crop seasons to investigate the effect of micronutrients on quantitative and qualitative characteristics of canola cultivars under late-season drought stress conditions. The experiments were arranged in a factorial split-plot design, with two irrigation treatments – normal irrigation (control) or restricted irrigation at flowering stage – and four foliar applications of Zn and Mn after rosette stage (F₁: Water, F₂: ZnSO₄, F₃: MnSO₄ and F₄: ZnSO₄ + MnSO₄) as the main factor. Winter canola cultivars, including Okapy, Hyola401 and Hyola308, as sub-factor. The results showed that limited irrigation at flowering reduced seed yield, oil percentage and fatty acids content in different canola cultivars. Most of the canola oil is composed of unsaturated fatty acids, and the occurrence of drought stress at the reproductive stage reduced oil quality. By contrast, the minimum yield loss was obtained from Hylon401 cultivar, an early mature cultivar. Overall, it is recommended Hylon401 cultivar for normal irrigation and Hylon308 cultivar for a drought environment when considered the acceptable seed yield in canola. In general, it is suggested that a suitable performance of canola seeds is achieved by foliar application of manganese and zinc.

KEYWORDS:

• Germination rate
• manganese
• oil composition
• seed yield
• varieties

Acknowledgement

The author thanks Dr. Lucas Cavalcante Costa for critical reading and editing of the manuscript.

Disclosure statement

No potential conflict of interest was reported by the author(s).

Author contributions

A.S. designed and performed the experiment. HR. TM. wrote the manuscript. M.N: was in charge of the conceptualization, methodology, project administration and the data analyzer. M.O and F.G helped in revising the manuscript and improved the language. All the authors have read and approved the final manuscript and agreed to the published version of the manuscript.

Data availability statement

The datasets used during the current study available from the corresponding author on reasonable request.

Additional information

Funding

This research did not receive any specific grant from funding agencies in the public, commercial, or not-for-profit sectors.