Effects of temperature, light and other treatments on seed germination of Leymus chinensis

Abstract

[143][144][145][146][147][148]. Leymus chinensis (Trin.) Tzvel., a perennial cool-season grass distributed widely in eastern Asia, is an ideal species for the rangeland industry and soil conservation, but the seed has a long dormant period and low germination rates. This study examined the effects of temperature, light and various treatments including stratification, H 2 SO 4 , NaOCl, gibberellic acid (GA 3 ) and 6-benzyl adenine (BA), on the germination of Leymus chinensis seed. Seed stored over 1 yr and germinated at a temperature regime of 25/15°C with a 12/12-h photoperiod germinated best, and had a germination rate of 30.3%, with a minimum germination time of 12 d. In these germination conditions, germinated seeds were counted after 15 d to determine the effects of other treatments upon freshly harvested seed germination. The final germination rate for freshly harvested seeds stratified at 4°C for 0 to 10 wk ranged from 8.5 to 37.3%. Germination rates were 14.0 and 14.8% when seeds were treated with 70% H 2 SO 4 for 3 and 6 min, respectively. Seed treated with 5.0% NaOCl germinated 17.5 and 16.0% when treated for 10 and 20 min, respectively. When seeds were soaked in 1000 mgL -1 GA 3 solution for 24 h, 42.3% germinated, while treatment with 50 mgL -1 of BA resulted in 50.3% germination. The results indicate that various dormancy mechanisms may exist in the species. These findings will be helpful to farmers and breeders in selecting suitable treatments to improve seed germination and establishment. Tzvel. est une graminée vivace de saison fraîche très répandue dans l'est de l'Asie. L'espèce est idéale pour l'aménagement de grands parcours et la conservation du sol, mais ses graines traversent une longue période de dormance et germent mal. L'étude devait préciser les effets de la température, de l'éclairage et de divers conditionnements comme la stratification et l'usage de H 2 SO 4 , de NAOCl, d'acide gibberelique (GA 3 ) et de 6-benzyle adénine (BA) sur la germination des semences. Les graines entreposées un an et mises à germer à un régime thermique de 25/15°C sur une photopériode de 12/12 h sont celles qui germent le mieux, avec un taux de germination de 30,3 % et au moins 12 jours pour la levée. Les auteurs ont dénombré les semences germées à la suite de ce traitement au bout de 15 jours en vue de mieux comparer les effets des autres conditionnements sur la germination des graines fraîchement récoltées. Le taux de germination final des semences fraîchement récoltées stratifiées à 4°C pendant 0 à 10 semaines varie de 8,5 à 37,3 %. Quand les semences trempent 3 ou 6 minutes dans une solution de H 2 SO 4 à 70 %, le taux de germination s'établit respectivement à 14,0 et à 14,8 %. Celles conditionnées avec une solution de NaOCl à 5,0 % pendant 10 ou 20 minutes donnent un taux de germination de 17,5 et 16,0 %, respectivement. Quand on les trempe 24 heures dans une solution de 1 000 mg de GA 3 par litre, les semences germent dans une proportion de 42,3 % contre 50,3 % quand on les conditionne avec une solution...

Initial characterisation of low and high seed dormancy populations of Lolium rigidum produced by repeated selection

“…The two CK tested, BAP and KIN, had no effect on germination of LD3 or HD3 seeds at 50 M, but previous studies have shown that the effects of exogenous CK on seed germination are variable (Nikolić et al, 2006 and references therein), and it is likely that specific CK have different effects in different species; additionally, the concentration applied in the current study may have been too low (e.g. Zhang et al, 2006). Moreover, BAP and KIN are potent in processes normally affected by trans-CK but they may not be relevant to processes affected by the cis-CK (discussed below).…”

Effects of chemical treatments and environmental factors on seed dormancy and germination of shepherd's purse (Capsella bursa-pastoris (L.) Medic.)

“…Considerable research on gibberellins as seed germination promoters has shown that application of GA 3 to dormant seeds can eliminate their natural chilling requirement (Gashi et al 2012). The physiological role of GA 3 as a promoter of dormant seed germination, through the induction of hydrolytic enzymes, has been documented in a wide range of plant species (Rogis et al 2004;Zhang et al 2006;Baskin & Baskin 2004). …”

Hormonal and temperature regulation of seed dormancy and germination in Leymus chinensis

“…Previous studies on seed dormancy and germination of L. chinensis have mainly focused on dormancy breaking methods (Yi 1994;He et al 2010), ABA content in the caryopses (Yi et al 1997) and mechanical resistance of different parts of the seed on seed germination (Ma et al 2008;Zhang et al 2006). Ma et al (2010) found that L. chinensis seed germination has a strict requirement for fluctuating temperature.…”