RESUMO
The significant horticultural crop, cauliflower (Brassica oleracea L. var. botrytis) is vulnerable to the excessive salt concentration in the soil, which contributes to its scaled-down growth and productivity, among other indices. The current study examines the efficacy of hydropriming, halopriming, and osmopriming on the physio-biochemical attributes and tolerance to salinity (100 mM NaCl) in cauliflower under controlled conditions. The results showed that the salinity (100 mM NaCl) has significant deleterious impacts on cauliflower seed germination, seedling growth, and photosynthetic attributes, and provoked the production of reactive oxygen species. In contrast, different priming approaches proved beneficial in mitigating the negative effects of salinity and boosted the germination, vigor indices, seedling growth, and physio-biochemical attributes like photosynthetic pigments, protein, and proline content while suppressing oxidative damage and MDA content in cauliflower seedlings in treatment- and dose-dependent manner. PCA revealed 61% (PC1) and 15% (PC2) of the total variance with substantial positive relationships and high loading conditions on all germination attributes on PC1 with greater PC1 scores for PEG treatments showing the increased germination indices in PEG-treated seeds among all the priming treatments tested. All 13 distinct priming treatments tried clustered into three groups as per Ward's approach of systematic categorization, clustering the third group showing relatively poor germination performances. Most germination traits exhibited statistically significant associations at the p < 0.01 level. Overall, the results established the usefulness of the different priming approaches facilitating better germination, survival, and resistance against salinity in the cauliflower to be used further before sowing in the salt-affected agro-ecosystems.
RESUMO
To detect genetic variations among different Simmondsia chinensis genotypes, two gene targeted markers, start codon targeted (SCoT) polymorphism and CAAT box-derived polymorphism (CBDP) were employed in terms of their informativeness and efficiency in analyzing genetic relationships among different genotypes. A total of 15 SCoT and 17 CBDP primers detected genetic polymorphism among 39 Jojoba genotypes (22 females and 17 males). Comparatively, CBDP markers proved to be more effective than SCoT markers in terms of percentage polymorphism as the former detecting an average of 53.4% and the latter as 49.4%. The Polymorphic information content (PIC) value and marker index (MI) of CBPD were 0.43 and 1.10, respectively which were higher than those of SCoT where the respective values of PIC and MI were 0.38 and 1.09. While comparing male and female genotype populations, the former showed higher variation in respect of polymorphic percentage and PIC, MI and Rp values over female populations. Nei's diversity (h) and Shannon index (I) were calculated for each genotype and found that the genotype "MS F" (in both markers) was highly diverse and genotypes "Q104 F" (SCoT) and "82-18 F" (CBDP) were least diverse among the female genotype populations. Among male genotypes, "32 M" (CBDP) and "MS M" (SCoT) revealed highest h and I values while "58-5 M" (both markers) was the least diverse. Jaccard's similarity co-efficient of SCoT markers ranged from 0.733 to 0.922 in female genotypes and 0.941 to 0.746 in male genotype population. Likewise, CBDP data analysis also revealed similarity ranging from 0.751 to 0.958 within female genotypes and 0.754 to 0.976 within male genotype populations thereby, indicating genetically diverse Jojoba population. Employing the NTSYS (Numerical taxonomy and multivariate analysis system) Version 2.1 software, both the markers generated dendrograms which revealed that all the Jojoba genotypes were clustered into two major groups, one group consisting of all female genotypes and another group comprising of all male genotypes. During the present investigation, CBDP markers proved more informative in studying genetic diversity among Jojoba. Such genetically diverse genotypes would thus be of great significance for breeding, management and conservation of elite (high yielding) Jojoba germplasm.
RESUMO
An efficient in vitro protocol has been established for clonal propagation of elite plant of Spilanthes calva DC., an important source of spilanthol, an antimalarial larvicidal compound. Nodal explants excised from field grown plant of S. calva DC. when reared on Murashige and Skoog's medium augmented with different cytokinins, viz. N(6)-Benzyladenine (BA), N(6)-(2-isopentenyl) adenine (2iP) and 6-furfuryl aminopurine (Kn), differentiated multiple shoots from the axils. BA at 10 µM proved optimum for elicitation of multiple shoots in 91.6 % cultures with an average of 7.12 shoots per explant within 6 weeks. The excised shoots rooted on half strength Murashige and Skoog's medium supplemented with 0.1 µM IBA. Micropropagated plants were hardened and transferred to field for acclimatization, where 95 % plants survived and were phenotypically similar to the donor plant. Random amplified polymorphic DNA (RAPD) and inter-simple sequence repeat (ISSR) markers were employed to evaluate the genetic fidelity amongst the regenerants. Eleven individuals, randomly chosen amongst a population of 120 regenerants were compared with the donor plant. A total of 71 scorable bands, ranging in size from 100 bp to 1,100 bp were generated by a combination of the two markers in the aforesaid plants. All banding profiles from micropropagated plants were monomorphic and similar to those of mother plant. The similarity values amongst the aforesaid plants varied from 0.967 to 1.000. The dendrogram generated through UPGMA (Unweighted Pair Group Method with arithmetic mean) analysis revealed 98 % similarity amongst them, thus confirming the genetic fidelity of the in vitro clones.
