Investigation of Seed Germination Indices for Early Selection of Salinity Tolerant 1 Genotypes: A Case Study in Wheat

Plant establishment is highly correlated with successful germination and seedling growth, the most sensitive and critical stages. Abiotic stresses by their limiting and adverse effects on these stages finally result in poor yield. Therefore, investigating resistance to salinity among genotypes of a desired plant is highly recommended for anticipated drought seasons. To study the effects of salinity on seed germination and initial growth of seedlings, a factorial experiment was conducted based on a completely randomized design with four replicates using three wheat (Triticum aestivum) genotypes (Zagros, Gascogen and Kuhdasht). Salinity levels included 0 (control), 3.5, and 7 dS m-1 (deci-Siemens per meter). The results indicated that salinity had a significant influence on different germination indices (P<0.05). In all the genotypes, with an increase in salinity levels, indices including germination percentage, germination rate, seed vigor, coefficient of germination rate, coleoptile to plumule ratio, and daily germination mean decreased. Unlike the mentioned indices, the ratio of the radicle to plumule and the mean of germination time increased. Zagros genotype showed more tolerant than the other two. Based on these results, it seems that germination indices may be effectively used in selecting tolerant plants to salinity stress.Open access journalThis item from the UA Faculty Publications collection is made available by the University of Arizona with support from the University of Arizona Libraries. If you have questions, please contact us at [email protected]

A robust method for haploid sugar beet in vitro proliferation and hyperhydricity reduction

Sugar beet is recalcitrant to in vitro tissue culture. Usually, proliferation of in vitro cultured rosette explants is a prerequisite for micropropagation. Although hormonal treatments can induce proliferation in sugar beet rosette explants, they may also result in some side effects. In vitro culture of sugar beet explants and some hormonal treatments make them more prone to hyperhydricity. Effects of media with different concentrations of 6-benzylaminopurine (BAP) and kinetin (Kin) on the proliferation and hyperhydricity of haploid sugar beet explants were investigated. It was observed that 0.2 mg L-1 Kin, with a reasonable amount of proliferation and minimum rate of hyperhydricity, performed better than BAP in different concentrations and combinations. The effect sizes of the treatments on the dependent variables were large. The correlation between proliferation and hyperhydricity of the treated explants was statistically negative and the association was large. However, the hormonal treatments without BAP or with the lowest amount of it produced the highest proliferation rate with the least hyperhydricity. The coefficient of determination was R2 quadratic = 0.885. The results suggest that, in comparison with BAP, Kin is a potent plant growth regulator for the proliferation of sugar beet haploid explants that causes the least hyperhydricity. Although explants proliferated better in the presence of 0.01 mg L-1 BAP in combination with Kin than under Kin alone, the hyperhydricity of the proliferated explants decreased their suitability for in vitro propagation