Agro-morphological characterization and qRT-PCR validation of SNAC1 and DREB1A drought tolerance genes expression in Okra (Abelmoschus esculentus L. Moench) seedlings

Abdulkareem  Khadijat Abdulhamid; Bello Abdultoyyib; Sidiq Khalilrahman Olatunji; Olayinka  Bolaji Umar; Kareem Isiaka; Mustapha  Oba Toyin

doi:10.56027/JOASD.092025

Authors

Abdulkareem Khadijat Abdulhamid University of Ilorin
Bello Abdultoyyib University of Ilorin https://orcid.org/0009-0004-9847-4702
Sidiq Khalilrahman Olatunji University of Ilorin
Olayinka Bolaji Umar University of Ilorin
Kareem Isiaka University of Ilorin
Mustapha Oba Toyin University of Ilorin

DOI:

https://doi.org/10.56027/JOASD.092025

Keywords:

RNA extraction, Gene expression, Drought stress, qRT-PCR, Agro-morphological characterization

Abstract

Okra (Abelmoschus esculentus L. Moench) belongs to the family Malvaceae, it is widely grown in most parts of the world. Its ubiquitous presence in African households significantly contributes to both the economic and nutritional well-being of communities. However, the escalating challenges posed by climate change, characterized by irregular rainfall and drought like conditions threatens Okra production. To address this growing concern, the development of stress-resistant Okra varieties has become necessary. This goal cannot be achieved without Identifying and validating Okra assessions with drought resistance genes. It is in this light that this study sought to validate and determine the expression of 2 drought resistance related genes DREB1A and SNAC1, using ERF4 as the reference gene in the most tolerant and least tolerant accessions of Okra, employing the qRT-PCR technique for gene expression analysis. Morphological parameters such as Plant height, Leaf number, length and width were recorded for the four Okra accessions (NGB 00332, NGB 00466, NGB 00349, and NGB 00373) to assess the impact of drought on the accessions to identify the least and most tolerant accessions used for molecular studies. NGB 00332 and NGB 00466 emerged as the most drought-tolerant and least drought-tolerant accession respectively. Findings from the gene expression studies revealed upregulation of DREB1A and SNAC1 with fold expression values of 70.03 and 2.95 respectively in the stressed samples of the most tolerant accession, while the least tolerant accession exhibits substantially lower gene expression levels with expression values 0.57 and 0.47 respectively, underscoring its vulnerability to drought stress. This study provides plant breeders with valuable insights for the selection of drought resilient Okra accession and development of superior Okra varieties capable of withstanding the looming threats posed by climate change, thereby enhancing food security.

Author Biographies

Bello Abdultoyyib, University of Ilorin

Department of Plant Biology, University of Ilorin, Ilorin, Nigeria

Sidiq Khalilrahman Olatunji, University of Ilorin

Department of Plant Biology, University of Ilorin, Ilorin, Nigeria

Olayinka Bolaji Umar, University of Ilorin

Department of Plant Biology, University of Ilorin, Ilorin, Nigeria

Kareem Isiaka, University of Ilorin

Department of Agronomy, University of Ilorin, Ilorin, Nigeria

Mustapha Oba Toyin , University of Ilorin

Department of Plant Biology, University of Ilorin, Ilorin, Nigeria

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