In Vitro Mutagenesis followed by Polymorphism Detection Using Start Codon Targeted Markers to Engineer Brown Spot Resistance in Kalanchoe

Abstract

Kalanchoe (Kalanchoe blossfeldiana) is a common potted flower that is popular throughout the world. Brown spot (caused by Stemphylium lycopersici) is one of the common foliage diseases in kalanchoe. This disease tends to infect leaves of kalanchoe plants in hot and humid environments, reducing their aesthetic value. The current investigation aimed to generate mutations resistant to brown spot in 'Mary' kalanchoe through chemical mutagenesis followed by molecular marker identification. Putative mutants were developed by treating embryogenic calluses with ethyl methanesulfonate (EMS) at median lethal doses (LD50)-either a 0.8% concentration for 2 hours or a 1.0% concentration for 0.5 hours. Brown spot crude toxin solution was used as the selection agent to identify diseaseresistant calluses during tissue culture. The optimal crude concentration (60%) was determined by soaking calluses with different concentrations of crude pathogen: 0%, 20%, 40%, 60%, and 80% (v/v). A total of 32 anti-brown spot lines were regenerated and tested for disease resistance with detached leaves. Three regenerated EMS mutant lines showed no obvious brown spot lesions on their leaves after the disease resistance assay and were subjected to polymorphism identification by start codon targeted (SCoT) molecular markers. Three (SCoT40, SCoT71, and SCoT72) of 45 selected primers were chosen to identify the mutants. This work may lay the foundation for further development of new disease-resistant cultivars of kalanchoe.

Morphological, molecular and resistance responses to soft-rot disease variability among plantlets of Phalaenopsis amabilis regenerated from irradiated protocorms

“…Moreover, disease resistance mutants have been regenerated through induced mutation in other plants such as abaca, banana, coffee and peanut (Yusnita et al 2005;Ibrahim et al 2018;Indrayanti et al 2018;Li et al 2019). Furthermore, irradiation may be employed to augment variation among regenerated plantlets (Jain 2005; and yielded abiotic stresstolerant (Widoretno et al 2003;Penna et al 2012;Widoretno et al 2012;Oladosu et al 2015;Rahayu and Sudarsono 2015;Suprasanna et al 2016) and biotic stress resistant (Yusnita et al 2005;Rai et al 2011;Sutanto et al 2014;Indrayanti et al 2018) mutant lines.…”

Development of a SCAR Marker Based on SCoT Polymorphisms for Sugarcane Smut Resistance

“…The start codon targeted (SCoT) polymorphism, which was developed by Collard and Mackill (2007), is a target gene marker technology based on translation initiation sites. Due to its simplicity of operation, low cost, rich polymorphism, and good repeatability, this technology has been successfully applied to various investigations such as genetic diversity (Shen et al 2016;Shekhawat et al 2018), population structure analysis (Tiwari et al 2016;Golkar and Nourbakhsh 2019) and disease resistance (Zeng et al 2014;Li et al 2019). In addition, the primer length of SCoT is 18 bp, with the same reaction conditions as conventional PCR, although with higher stability (Shen et al 2016;Chen et al 2017).…”