IDX法快速测定火炬松种子生活力的研究

种子发芽能力是表明种子播种品质的重要指标之一。种子播种品质的测定通常采用发芽试验,由于发芽试验持续时间长,而且有时受种子自身休眠的限制,发芽试验前首先要打破休眠,无疑相对增加了检验时间,无法满足种子生产、管理和贸易的需要。为此,人们一直在探求一种既简便又快速、可靠的测定种子生活力的方法。1957年Simak[1]首次用BaL作衬比剂测定欧洲赤松种子生活力,我国陈幼生等[2,3]用KI作衬比剂测定湿地松、马尾松种子的生活力。由于树种的多样性和特异性,这项技术还未能用于所有树种。1980年Simak[4]又提出水可作为广谱衬比剂而适用于所有树种,并成功地用IDX法测定了美国海岸松种子生活力。但至今再未见有关水衬比测定种子生活力的报道。本文以具有休眠习性的火炬松种子为研究对象,研究其生活力水衬比测定技术,为开展其它树种种子生活力的IDX法快速测定制定出较系统的实验体系。

Studies on IDX Method for Testing Viability of Loblolly Pine Seeds

This paper choses water as contrast agent for testing loblolly pine seed viability.The IDX method proceeded as follows:The seeds were soaked in water at 25 ℃ for 24 hours,then put on germination medium at 25 ℃ for 24 hours.After that the seeds were dried at 30 ℃ for 5 hours with SiO2.The dried seeds were radiographed with NO.3 enlarging paper under the following condition:Voltage=25 kV,electric current=3 mA,exposure time=70 s,focus-film-distance=25 cm.The image of seed with seed structure was considered as dead seed.According to this standard,the seeds viability by IDX method agreed quite well with the actual germination percentage.