Endophytic Microbes Boost Drought Tolerance and Yield in Sunflower (Helianthus annuus L.)

• Rashid Khan

  Department of Agronomy, Faculty of Agriculture, Gomal University, D.I. Khan, Khyber Pakhtunkhwa, Pakistan.

  Author

• Haris Khan

  Gomal Center of Biochemistry and Biotechnology, Gomal University, D.I. Khan, Khyber Pakhtunkhwa, Pakistan.

  Author

• Sajid Ali

  Gomal Center of Biochemistry and Biotechnology, Gomal University, D.I. Khan, Khyber Pakhtunkhwa, Pakistan.

  Author

• Nabeel Akbar

  Department of Agronomy, Faculty of Agriculture, Gomal University, D.I. Khan, Khyber Pakhtunkhwa, Pakistan.

  Author

• Rida Batool

  Department of Plant Sciences Quaid-i-Azam University, Islamabad, pakistan

  Author

• Mudassar Shumail Khan

  Department of Soil Science, Faculty of Agriculture, Gomal University, D.I. Khan, Khyber Pakhtunkhwa, Pakistan.

  Author

Drought represents a major constraint to sunflower yield in arid and semiarid regions, demanding innovative agronomic practices. The current study quantifies the contribution of endophytic microbiota to drought resilience in Helianthus annuus L. during a field experiment conducted in Dera Ismail Khan during the 2025 cropping season. Trials were sited on a farmer’s plot bordering Channel No. 6 of the Gomal Zam Dam command area, employing a randomized complete block design with three replicates. Seventeen physiological, biochemical and yield related metrics were systematically assessed, including plant stature, chlorophyll fluorescence, stomatal conductance, antioxidant enzyme activities and final yield components. Data demonstrated that inoculation with selected endophytic strains, with Endophyte B exhibiting the strongest effect, elicited statistically superior results across all measured traits relative to uninoculated controls. Enhanced catalase and peroxidase activities, diminished malondialdehyde accumulation, and elevated accumulation of osmotic regulators together attested to effective oxidative damage suppression. Yield parameters, including capitulum diameter and seed set per capitulum, responded positively and proportionately. Collectively, these observations endorse endophytic microbes as a viable, environmentally benign approach to bolster sunflower resilience against drought, aligning with the objectives of climate-smart agronomy.

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