Physiological and biochemical responses of Kinnow mandarin (Citrus nobilis × Citrus deliciosa) to EMS induced mutagenesis

Abstract

The present study was carried out to enhance the genetic variability in Kinnow mandarin (Citrus nobilis Loureiro Physiological and biochemical responses of Kinnow mandarin (Citrus nobilis × Citrus deliciosa) to EMS induced mutagenesis Citrus deliciosa Tenora) using ethyl methanesulfonate (EMS) during 2016-17 and 2017-18. Plants created with different doses of EMS concentration, viz. 0.05%, 0.1%, 0.2% and 0.5% were examined for the various physiological and biochemical alterations in putative mutants aged six years and compared with the wild type (WT). A dose-dependent decrease in leaf area was recorded in the mutants with increasing doses of EMS concentration and as compared to WT, maximum reduction of 135.52 and 104.92% was witnessed in the mutants E-19 and E-17 developed from 0.5% EMS, whereas the leaves were more succulent in E-16. Chlorophyll a content was higher than chlorophyll b in the mutated population. As compared to WT, maximum decrease in chlorophyll a, total chlorophyll was noticed in the mutants E-19 generated from 0.5% EMS. Contrary to the physiological alterations, the total phenol, proline and total protein content in the mutants were upregulated by nearly two fold in the mutants developed beyond 0.1% EMS. Significant increase was also noticed in the antioxidant enzymes SOD, CAT, POX and GR activity in the mutants E-16 to E-20 induced from 0.5% EMS. The variation in traits of interest observed in the present study such as better leaf succulency and upregulated antioxidant enzyme activity in the mutant E-16 (0.5% EMS) suggests that the developed mutant could be utilised in Kinnow improvement for abiotic stress tolerance.

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

“…There is a great demand for Kinnow fruits for processing into juice. However, it could not get a boost due to its high seediness leading to delayed bitterness ( Mallick et al., 2016 ; Kumar et al., 2021 ). The development of low-seeded scion varieties is a major target for citrus breeders worldwide, which, however, is difficult to achieve through conventional breeding.…”

EMS induced in vitro mutagenesis for solid mutant induction and validation of mutants using morphological and molecular tools in kinnow mandarin (Citrus nobilis × Citrus deliciosa)

“…In India after mango and banana, citrus occupies third position with an area of 1.10 million ha and a production of 14.85 million metric tonnes (Anonymous 2022). Among citrus group, kinnow an inter-specific mandarin hybrid of Citrus nobilis Loureiro × Citrus deliciosa Tenora has revolutionized the citrus industry of India because of its wider adaptability, attractive golden yellow peel, higher juice recovery, quality and affordable market price (Kumar et al 2021). This golden fruit also has the potential for juice processing provided low seeded kinnow mandarin (<10 seeds/fruit) are developed compared to 30-35 seeds/fruit (Kumar et al 2021).…”