Improved salt-tolerance of transgenic soybean by stable over-expression of AhBADH gene from Atriplex hortensis

Abstract

An effective strategy for increasing the productivity of major crops under salt stress conditions is the development of transgenics that harbor genes responsible for salinity tolerance. Betaine aldehyde dehydrogenase (BADH) is a key enzyme involved in the biosynthesis of the osmoprotectant, glycine betaine (GB), and osmotic balance in plants, and several plants transformed with BADH have shown signi cant improvements in salt and drought tolerance. However, very few eld-tested transgenic cultivars have been reported, as most of the transgenic studies are limited to laboratory or green house experiments. In this study, we demonstrated through eld experiments that BADHfrom Atriplex hortensis (AhBADH) confers salt tolerance when transformed into soybean (Glycine max L.). AhBADH was successfully introduced into soybean by Agrobacterium mediated transformation. A total of 256 transgenic plants were obtained, out of which 47 lines showed signi cant enhancement of salt tolerance compared to non-transgenic control plants. Molecular analyses of the transgenic line TL7 with the highest salt tolerance exhibited stable inheritance and expression of AhBADH in progenies with a single copy insertion. TL7 exhibited stable enhanced salt tolerance and improved agronomic traits when subjected to 300mM NaCl treatment. Currently, the transgenic line TL7 with stable enhanced salt tolerance, which has been cleared for environmental release, is under biosafety assessment. TL7 stably expressing AhBADH could then be applied in commercial breeding experiments in order to genetically improve salt tolerance in soybean. Key MessageThe salt-tolerance of transgenic soybean cleared for environmental release was improved by stable overexpression of AhBADH gene from Atriplex hortensis, which was demonstrated through molecular analysis and eld experiments.

Exogenous Selenium Endows Salt-Tolerant and Salt-Sensitive Soybeans with Salt Tolerance through Plant-Microbial Coactions

“…However, soil salinization caused by environmental degradation has adversely impacted soybean quality and yield, posing a serious threat [6]. In saline soil, the redox balance within soybean plants is disrupted, resulting in excessive production of reactive oxygen species and triggering oxidative stress responses that damage cell membranes and organelles [16]. Moreover, the imposition of salt stress disrupts the crucial processes of water and nutrient absorption in the intricate root architecture of soybeans, particularly concerning essential metal cations, thereby precipitating imbalances in nutrient distribution [17,18].…”