Evaluating surface drying and re-drying for wheat seed priming with polyamines: effects on emergence, early seedling growth and starch metabolism

Abstract

This study was conducted to investigate the benefits associated with re-drying after seed priming with polyamines. Wheat (cv. AS-2002) seeds were soaked in 10 and 20 mg L -1 aerated solutions of spermidine (Spd), putrescine (Put) and spermine (Spm), and distilled water (CK2) for 12 h at 28 ± 2°C. Untreated seeds (CK1) and priming in distilled water (CK2) were taken as control treatments. Seeds were primed in two sets: In one set, after each treatment, seeds were given three surface washings with distilled water and dried closer to original moisture; in the other, seeds were only surface dried and used immediately. Use of surface-dried seeds after priming was more effective since it reduced emergence time and synchronized the emergence. Moreover, final emergence, shoot and root length, seedling fresh and dry weight were also improved. Improved starch metabolism was considered possible reason of seed invigoration. All the seed treatments resulted in a lower electrical conductivity of seed leachates compared with control; however, there was more decrease in seeds re-dried after priming than the seeds surface dried after priming. Although the effect of all the polyamines was stimulatory, Spd was the more effective for most of the attributes studied. Nonetheless, Put was more effective for seedling fresh and dry weights. All the polyamines were more effective at lower concentrations except Spm, which improved the coefficient of uniformity of emergence at high concentration. To conclude, if immediate sowing is possible, use of surface-dried seeds after priming may be more effective; seed priming with 10 mg L -1 Spd was the most effective technique when surface dried.

Exogenous Application of Polyamines Improves Germination and Early Seedling Growth of Hot Pepper

“…Enhanced germination and vigor of hot pepper seeds could be the result of enhanced metabolic activities (efficient mobilization and utilization of seed reserves and better genetic repair) (Srivastava, 2002;Farooq et al, 2008). These results are in line with the earlier findings (He et al, 2002;Farooq et al, 2007;2011).…”

“…During this study, all of the PAs stimulated the seed germination and seedling growth compared to control but Put was found more effective. Put at lower concentrations was found better as compared to other PAs, which confirms the results of Farooq et al (2008) but contrast to the findings of Farooq et al (2007) and Farooq et al (2011).…”

“…Moreover, PAs are also accumulated in plants and perform their function in plants under normal as well as stress conditions. Exogenous PAs may influence germination of isolated embryos depending on the type of polyamine, its concentration, and the state of the embryo dormancy (Farooq et al, 2011).…”

“…wheat (Iqbal and Ashraf, 2005;Farooq et al, 2011), sunflower (Farooq et al, 2007), rice (Farooq et al, 2008) and tomato (Afzal et al, 2009). Nonetheless, no study has been reported to evaluate the effects of polyamine seed priming on hot pepper.…”

Ameliorative Effect of Proline and Ascorbic Acid on Seed Germination and Vigour Parameters of Tomato (Solanum lycopersicum L.) Under Salt Stress

“…Tomatoes inhabiting in saline environments lead to restricted root growth (Zhang et al, 2016). Farooq et al, (2011) reported that presoaking of seeds with different salts improved the seedling emergence, shoot and root length. In same way, seedling vigour and seedling biomass showed inverse relationship with salt concentrations.…”