High efficient de novo root-to-shoot organogenesis in Citrus jambhiri Lush.: Gene expression, genetic stability and virus indexing

Abstract

A protocol for high-frequency direct organogenesis from root explants of Kachai lemon (Citrus jambhiri Lush.) was developed. Full-length roots (~3 cm) were isolated from the in vitro grown seedlings and cultured on Murashige and Skoog basal medium supplemented with Nitsch vitamin (MSN) with different concentrations of cytokinin [6-benzylaminopurine, (BAP)] and gibberellic acid (GA3). The frequency of multiple shoot proliferation was very high, with an average of 34.3 shoots per root explant when inoculated on the MSN medium supplemented with BAP (1.0 mg L–1) and GA3 (1.0 mg L–1). Optimal rooting was induced in the plantlets under half strength MSN medium supplemented with indole-3-acetic acid (IAA, 0.5–1.0 mg L–1). IAA induced better root structure than 1-naphthaleneacetic acid (NAA), which was evident from the scanning electron microscopy (SEM). The expressions of growth regulating factor genes (GRF1 and GRF5) and GA3 signaling genes (GA2OX1 and KO1) were elevated in the regenerants obtained from MSN+BAP (1.0 mg L-1)+GA3 (1.0 mg L-1). The expressions of auxin regulating genes were high in roots obtained in ½ MSN+IAA 1.0 mg L-1. Furthermore, indexing of the regenerants confirmed that there was no amplicons detected for Huanglongbing bacterium and Citrus tristeza virus. Random amplified polymorphic DNA (RAPD) and inter simple sequence repeat (ISSR) markers detected no polymorphic bands amongst the regenerated plants. This is the first report that describes direct organogenesis from the root explant of Citrus jambhiri Lush. The high-frequency direct regeneration protocol in the present study provides an enormous significance in Citrus organogenesis, its commercial cultivation and genetic conservation.

In Vitro Propagation of Algerian Lavandula Stoechas and Assessment of Biochemical Composition and Their Antioxidant Activity

“…Kousalya & Narmatha Bai (2016) 42 found that applying GA3 and BAP combination in a ratio of 1:1 increases shoot elongation but also shoot multiplication of Canscora decussate. This was also supported by in vitro cultures of Citrus jambhiri explants which had a high frequency of multiple shoot proliferation after growing in the presence of GA3/ BAP ratio was 1:1 in the culture media 43 . Nevertheless, in many works on the in vitro culture of the Lavender species, the most effective method for shoot propagation was MS media supplemented with BA hormone alone 33,,44,45 .…”

Gentianella lutescens subsp. carpatica J. Holub.: Shoot Propagation In Vitro and Effect of Sucrose and Elicitors on Xanthones Production

“…They can be easily developed into shoots that ensure clonal fidelity [ 33 ]. Genetic fidelity and true-to-type regenerated plants are very important for both the germplasm maintenance for plant conservation purposes and mass shoot propagation that ensures a continuous supply of uniform genetic plant material for large-scale secondary metabolite production [ 34 , 35 ].…”

Molecular and histological validation of modified in ovulo nucellus culture based high-competency direct somatic embryogenesis and amplitude true-to-the-type plantlet recovery in Kinnow mandarin

“…The ISSR markers did not reveal any variation in the established emblings, thus confirming genetic stability with the current protocol. In citrus, earlier studies also suggest the efficiency of ISSR markers in assessing genetic stability ( Siragusa et al., 2007 ; Meziane et al., 2017 ; Devi et al., 2021 ). The current study is the first report on the genetic stability of in ovulo culture-induced plants obtained through DSE in Kinnow mandarin.…”