Effects of physical and chemical treatments of seed dormancy breaking on seedling quality index (QI) of Caspian locust (Gleditsia caspica Desf.)

Wien

2016

S. 157-172

Artikel aus einer Zeitschrift

200200067

This paper reports the effects of different treatments of seed dormancy breaking on seed germination and seedling quality index (QI) of Caspian locust (Gleditsia caspica) under laboratory and greenhouse conditions. The employed treatments included sulfuric acid (98%) for 15, 30, 45, 60, 90, 120, and 150 minutes, potassium nitrate (1%) for 12, 24, 48, and 72 hours, cold water for 1, 2, 3, 4, and 6 days at room temperature, boiling water at 40, 60, 80, and 100 ¢ªC, and seed coat removal. The results indicated that treatments of seed coat removal and sulfuric acid for 45 up to 150 min were the most efficient on improvement of germination percentage, as it increased from 4% in the control treatment to 100% observed in the above-mentioned treatments. Also, the results showed that maximal seedling quality index was obtained in seeds immersed in sulfuric acid for 60 min, such that the given index increased by 42.8% compared to the control. In contrast, minimal seedling quality index was observed in boiling water at 60 ¢ªC. This paper demonstrates that sulfuric acid has not only been the most efficient treatment in breaking physical seed dormancy improving germination percentage from 4% to 100% but also led to increase in Caspian locust seedling quality index (up to 305% compared to the control) under greenhouse conditions. The results indicated that soaking in boiling water (100 ¢ªC) could be the least costly and the most applicable treatment which both had an acceptable effect on Caspian locust seed germination (77.3%) and improved Dickson¡¯s quality index (Up to 155%). In addition, sturdiness quotient presented more acceptable results compared to shoot/root dry weight ratio.
Keywords: Seed coat removal, Gleditsia caspica, DQI, sulfuric acid, sturdiness quotient, dormancy breaking