Buah Stephen, Tindamanyire Jimmy Moses, Namanya Priver, Kubiriba Jerome, Arinaitwe Geoffrey, Paul Jean-Yves, Harding Robert, Dale James, Tushemereirwe Wilberforce
National Agricultural Research Laboratories, Kawanda, Wakiso, Uganda.
Kyambogo University, Kampala, Uganda.
Plant Biotechnol J. 2025 Sep;23(9):3713-3726. doi: 10.1111/pbi.70190. Epub 2025 Jun 10.
Biofortification of staple crops is a sustainable strategy to deliver essential micronutrients to impoverished populations in developing countries. Banana is a highly valued crop consumed by over 75% of Ugandans. However, the starchy green cooking bananas have very low levels of pro-vitamin A (PVA) and heavy dietary reliance on them has been associated with vitamin A deficiency (VAD). Two banana cultivars, hybrid M9 and Nakitembe, were selected for PVA biofortification. A phytoene synthase 2a (MtPsy2a) gene was transformed into the selected cultivars under the control of the constitutive maize polyubiquitin1 promoter or the banana fruit-preferred ACC oxidase (ACO) promoter. Plants were regenerated on selective media and putatively transgenic plants confirmed by PCR. A total of 356 and 162 transgenic events for M9 and Nakitembe, respectively, were planted in a confined field trial (CFT). Transgenic plants were assessed against non-transformed controls. Selection was based on phenotype, cycle time, yield, β-carotene equivalents (β-CE) and transgene copy number. There were no significant variations in cycle time, but some phenotypic differences were observed between transgenic and non-transgenic controls. Transgenic fruits had yellow to orange fruit pulps, unlike pulp from non-transgenic controls that were paler. On average, fruit from transgenic M9 and Nakitembe accumulated fourfold and threefold more β-CE than non-transgenic controls, respectively. Five elite lines each of M9 and Nakitembe have been selected for national agronomic performance trials that will aid the selection of lead events to be considered for environmental release.
主粮作物的生物强化是一种向发展中国家贫困人口提供必需微量营养素的可持续战略。香蕉是一种深受乌干达人喜爱的作物，超过75%的乌干达人食用香蕉。然而，淀粉质的绿色烹饪香蕉中维生素A原（PVA）含量极低，对其过度的膳食依赖与维生素A缺乏症（VAD）有关。选择了两个香蕉品种，即杂交M9和Nakitembe进行PVA生物强化。在组成型玉米多聚泛素1启动子或香蕉果实偏好的ACC氧化酶（ACO）启动子的控制下，将八氢番茄红素合酶2a（MtPsy2a）基因转入选定的品种中。在选择培养基上再生植株，并通过PCR确认推定的转基因植株。分别有356个和162个M9和Nakitembe的转基因事件被种植在一个封闭田间试验（CFT）中。对转基因植株与未转化对照进行评估。选择基于表型、生育期、产量、β-胡萝卜素当量（β-CE）和转基因拷贝数。生育期没有显著差异，但转基因和非转基因对照之间观察到一些表型差异。转基因果实的果肉为黄色至橙色，与非转基因对照颜色较浅的果肉不同。平均而言，转基因M9和Nakitembe的果实积累的β-CE分别比非转基因对照多四倍和三倍。已分别为M9和Nakitembe挑选了五个优良品系进行全国农艺性能试验，这将有助于选择可考虑进行环境释放的主导事件。
