{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,1,5]],"date-time":"2026-01-05T09:03:53Z","timestamp":1767603833111,"version":"3.48.0"},"reference-count":34,"publisher":"MDPI AG","issue":"1","license":[{"start":{"date-parts":[[2026,1,4]],"date-time":"2026-01-04T00:00:00Z","timestamp":1767484800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100012166","name":"National Key R&D Program of China","doi-asserted-by":"publisher","award":["2023YFD2200702-3"],"award-info":[{"award-number":["2023YFD2200702-3"]}],"id":[{"id":"10.13039\/501100012166","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100010038","name":"earmarked fund for China Agriculture Research System","doi-asserted-by":"publisher","award":["CARS-14-2-31"],"award-info":[{"award-number":["CARS-14-2-31"]}],"id":[{"id":"10.13039\/501100010038","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Plants"],"abstract":"<jats:p>Coconut genetic improvement remains challenging due to low regeneration efficiency and limited transformation success. We optimized major components of a gene gun-mediated transient transformation system and evaluated explant types to support future establishment of a stable transformation pipeline. Three reporter genes (eGFP, GUS, and RUBY) were compared in coconut callus, and eGFP was selected as the most suitable due to its strong and non-destructive fluorescence. Background interference in GUS staining was reduced by adjusting the methanol\u2013GUS ratio to 4:10. Single-factor optimization using callus tissue identified 0.4 M mannitol, 300\u2013500 \u03bcg gold particles, 1.5 \u03bcg plasmid DNA, a 6.5 cm target distance, and 7 MPa pressure as effective parameters for biolistic delivery. Among the callus types, spongy callus showed strong transient eGFP expression but displayed loose and watery morphology consistent with non-embryogenic callus. In contrast, crumbly and smooth callus exhibited compact structures previously associated with embryogenic competence, although transient expression levels were lower. Among differentiated tissues, germinated zygotic embryo plumules and distal young leaflets exhibited moderate transient expression, supporting their suitability as transformation targets. These findings provide practical guidance on reporter selection, parameter refinement, and explant choice for future establishment of an efficient genetic transformation system in coconut.<\/jats:p>","DOI":"10.3390\/plants15010150","type":"journal-article","created":{"date-parts":[[2026,1,5]],"date-time":"2026-01-05T08:40:53Z","timestamp":1767602453000},"page":"150","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Optimization\u00a0of Gene Gun-Mediated Transient Transformation and Explant Suitability in Coconut"],"prefix":"10.3390","volume":"15","author":[{"given":"Mingjun","family":"Ma","sequence":"first","affiliation":[{"name":"State Key Laboratory of Tropical Crop Breeding\/Sanya Research Institute\/Coconut Research Institute, Chinese Academy of Tropical Agricultural Sciences, Wenchang 571339, China"},{"name":"College of Horticulture and Forestry Sciences, Huazhong Agricultural University, Wuhan 430070, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Hanlu","family":"Su","sequence":"additional","affiliation":[{"name":"State Key Laboratory of Tropical Crop Breeding\/Sanya Research Institute\/Coconut Research Institute, Chinese Academy of Tropical Agricultural Sciences, Wenchang 571339, China"},{"name":"College of Horticulture and Forestry Sciences, Huazhong Agricultural University, Wuhan 430070, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Hao","family":"Nie","sequence":"additional","affiliation":[{"name":"State Key Laboratory of Tropical Crop Breeding\/Sanya Research Institute\/Coconut Research Institute, Chinese Academy of Tropical Agricultural Sciences, Wenchang 571339, China"},{"name":"College of Horticulture and Forestry Sciences, Huazhong Agricultural University, Wuhan 430070, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Xiaomeng","family":"Fang","sequence":"additional","affiliation":[{"name":"State Key Laboratory of Tropical Crop Breeding\/Sanya Research Institute\/Coconut Research Institute, Chinese Academy of Tropical Agricultural Sciences, Wenchang 571339, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0251-5684","authenticated-orcid":false,"given":"Saeed","family":"Rauf","sequence":"additional","affiliation":[{"name":"State Key Laboratory of Tropical Crop Breeding\/Sanya Research Institute\/Coconut Research Institute, Chinese Academy of Tropical Agricultural Sciences, Wenchang 571339, China"},{"name":"Department of Plant Breeding & Genetics, College of Agriculture, University of Sargodha, Sargodha 40100, Pakistan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Saira","family":"Batool","sequence":"additional","affiliation":[{"name":"State Key Laboratory of Tropical Crop Breeding\/Sanya Research Institute\/Coconut Research Institute, Chinese Academy of Tropical Agricultural Sciences, Wenchang 571339, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4215-019X","authenticated-orcid":false,"given":"Yin Min","family":"Htwe","sequence":"additional","affiliation":[{"name":"State Key Laboratory of Tropical Crop Breeding\/Sanya Research Institute\/Coconut Research Institute, Chinese Academy of Tropical Agricultural Sciences, Wenchang 571339, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4644-9877","authenticated-orcid":false,"given":"Dapeng","family":"Zhang","sequence":"additional","affiliation":[{"name":"State Key Laboratory of Tropical Crop Breeding\/Sanya Research Institute\/Coconut Research Institute, Chinese Academy of Tropical Agricultural Sciences, Wenchang 571339, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Peng","family":"Shi","sequence":"additional","affiliation":[{"name":"State Key Laboratory of Tropical Crop Breeding\/Sanya Research Institute\/Coconut Research Institute, Chinese Academy of Tropical Agricultural Sciences, Wenchang 571339, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Zhiying","family":"Li","sequence":"additional","affiliation":[{"name":"State Key Laboratory of Tropical Crop Breeding\/Sanya Research Institute\/Coconut Research Institute, Chinese Academy of Tropical Agricultural Sciences, Wenchang 571339, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Qun","family":"Yu","sequence":"additional","affiliation":[{"name":"State Key Laboratory of Tropical Crop Breeding\/Sanya Research Institute\/Coconut Research Institute, Chinese Academy of Tropical Agricultural Sciences, Wenchang 571339, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Xiangman","family":"He","sequence":"additional","affiliation":[{"name":"State Key Laboratory of Tropical Crop Breeding\/Sanya Research Institute\/Coconut Research Institute, Chinese Academy of Tropical Agricultural Sciences, Wenchang 571339, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8473-5386","authenticated-orcid":false,"given":"Yong","family":"Wang","sequence":"additional","affiliation":[{"name":"State Key Laboratory of Tropical Crop Breeding\/Sanya Research Institute\/Coconut Research Institute, Chinese Academy of Tropical Agricultural Sciences, Wenchang 571339, China"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2026,1,4]]},"reference":[{"key":"ref_1","unstructured":"McKeon, T.A., Hayes, D.G., Hildebrand, D.F., and Weselake, R.J. 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