Full Length Research Article
Induction of salinity tolerance in Basmati rice varieties by in vitro step up NaCl treatment method
Naveeda Batool, Humera Afrasiab*
Adv. life sci., vol. 8, no. 4, 2021
*- Corresponding Author: Humera Afrasiab (Email: humera.botany@pu.edu.pk)
Authors' Affiliations
Abstract
Background: Rice crop has been identified as salt susceptible which has negative effects on both seedling and reproductive stages. Soil salinity is ranked second most important abiotic element that drastically affects rice productivity worldwide. To meet the ever-escalating rice demand of increasing population, new rice varieties with potential of growing on saline soils through exploitation of genetic variability is the only option. The current study is aimed to induce salinity tolerance in salt sensitive Basmati rice varieties (Basmati-385, Super Basmati and Basmati-2000) through in vitro step up NaCl treatment method.
Methods: In the present study, salt tolerant calli of salt sensitive Basmati rice varieties were obtained through in vitro step up NaCl treatment method. M1 generation was obtained from regeneration of these salt tolerant calli in salt free medium. M2 and M3 generation were grown and harvested under salinity stress.
Results: Maximum callus induction was obtained for all Basmati rice varieties in MS medium fortified with 2.0 mg/L 2,4-D. These calli were subjected to in vitro step up NaCl treatments and maximum NaCl tolerance level for calli of all Basmati varieties was 1.0%. Basmati-385 and Basmati-2000, showed 75 and 85% regeneration frequency respectively in MS medium containing 2.0 mg/L BAP with 0.5 mg/L NAA, while Super Basmati gave 79% frequency for regeneration in MS medium fortified with 3.0 mg/L BAP with 0.5 mg/L NAA. A decrease in all the selected agronomical and morphological parameters was observed in M2 and M3 generations of all the varieties under saline conditions as compared to parent plants.
Conclusion: This study confirms that salinity tolerance can be induced in salt sensitive Basmati rice varieties through in vitro step up NaCl treatment method.
