title: Effect of air desiccation and salt stress factors on in vitro regeneration of rice (Oryza sativa L.).
abstract: Enhancement of callus induction and its regeneration efficiency through in vitro techniques has been optimized for 2 abiotic stresses (salt and air desiccation) using 3 rice genotypes viz. BR10, BRRI dhan32 and BRRI dhan47. The highest frequency of callus induction was obtained for BRRI dhan32 (64.44%) in MS medium supplemented with 2, 4-D (2.5 mgL(-1)) and Kin (1.0 mgL(-1)). Different concentrations of NaCl (2.9, 5.9, 8.8 and 11.7 gL(-1)) were used and its effect was recorded on the basis of viability of calli (VC), relative growth rate (RGR), tolerance index (TI) and relative water content (RWC). It was observed that in all cases BRRI dhan47 showed highest performance on tolerance to VC (45.33%), RGR (1.03%), TI (0.20%) and RWC (10.23%) with 11.7 gL(-1) NaCl. Plant regeneration capability was recorded after partial air desiccation pretreatment to calli for 15, 30, 45 and 60 h. In this case BRRI dhan32 gave maximum number of regeneration (76.19%) when 4 weeks old calli were desiccated for 45 h. It was observed that air desiccation was 2-3 folds more effective for enhancing green plantlet regeneration compared to controls. Furthermore, desiccated calli also showed the better capability to survive in NaCl induced abiotic stress; and gave 1.9 fold (88.80%) increased regeneration in 11.7 gL(-1) salt level for BRRI dhan47. Analysis of variance (ANOVA) showed that the genotypes, air desiccation and NaCl had significant effect on plant regeneration at P < 0.01.
authors.affiliation: a Plant Genetic Engineering Lab; Institute of Biological Sciences ; University of Rajshahi ; Rajshahi , Bangladesh.
authors.forename: Abu Baker
authors.initials: AB
authors.lastname: Siddique
authors.forename: Israt
authors.initials: I
authors.lastname: Ara
authors.forename: S M Shahinul
authors.initials: SM
authors.lastname: Islam
authors.forename: Narendra
authors.initials: N
authors.lastname: Tuteja
mesh_terms: D000222:Adaptation, Physiological / Q000187:drug effects; D000388:Air; D000704:Analysis of Variance; D003470:Culture Media / Q000494:pharmacology; D003890:Desiccation; D005838:Genotype; D012275:Oryza / Q000187:drug effects / Q000254:growth & development / Q000502:physiology*; D010937:Plant Growth Regulators / Q000494:pharmacology; D012038:Regeneration / Q000187:drug effects*; D012639:Seeds / Q000187:drug effects / Q000502:physiology; D012965:Sodium Chloride / Q000494:pharmacology*; D013312:Stress, Physiological / Q000187:drug effects*; D014867:Water / Q000378:metabolism
chemical_list: D003470:Culture Media; D010937:Plant Growth Regulators; D014867:Water; D012965:Sodium Chloride
keywords: 2,4-D, 2,4-Dichlorophenoxy acetic acid; BAP, 6-Benzyl amino purine; Bangladeshi Indica rice cultivars; CH, casein hydrolysate; ICn = number of inoculated callus.; Kin, kinetin; MS, Murashinge and Skoog; NAA, α-napthalene acetic acid; Oryza sativa; VCn = number of viable callus; abiotic stress; callus induction; d, day; h, hour; mature embryos; plant regeneration; w, week