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种子休眠妨碍了向日葵种的研究及其在改良栽培向日葵(Helianthus annuus L.)的育种程序中的应用。测验了数种种子处理方法,测定其在打破许多野生向日葵种的强烈的种子休眠系统上的效率。第一个处理(称为完整处理)包括种子的机械多次划破、于100毫克/升赤霉酸液中浸泡1小时及去除种壳。其他处理是该程序的简化和三个应用赤霉酸和2-氯乙基-次磷酸的完整种子处理。结果表明:去除种壳和种皮的处理最为有效,使许多种(包括极难萌发的一年生沙漠种)的萌发率提高到90%以上,将多次划破的种子置于100毫克/升赤霉酸液中浸泡1小时能促进某些种的萌发。将完整种子置于100毫克/升赤霉酸液中浸泡1小时或于500毫克/升2-氯乙基-次磷酸液中浸泡1小时均不能促进萌发。完整种子置于100毫克/升或100毫克/升赤霉酸液中培养10天可促进萌发,但形成非正常苗,虽然完整处理复杂,但其萌发率高,且材料间变异最小,因而推荐完整处理作为最佳的方法。许多作物育种家都关注把野生向日葵种作为改良栽培向日葵(Helianthus annuus L.)的基因资源,但强烈的种子休眠系统妨碍了这些物种的利用。在所有的野生种中均存在不同强度的种子休眠系统,但在一年生沙漠种H.deserficola Heiser、H.anomalus Blake和H.hiveus亚种fephrods(A.GrAy)Heiser(Heiser等,1969)尤为强烈。这些旱生种作为耐旱基因资源具有特别重要的价值。据恶,某些多年生种的休眠也非常强烈(Heiser,1916)。为确保野生向日葵种子萌发良好,已应用了数种方法。Heiser等(1969)报道一般最有效的方法是将种子播种于盆内,每移出室外3周至1个月,使其置于不同温度(包括冻融)之下。这种方法可促进萌发,但极少超过50%,且对一年生旱生种无效。对旱生种也应用了其他方法,包括湿润和干燥交替、多次换水冲洗和浸泡种子,但萌发率极少达到10%。据研究(Kumar和Sastry,1974、1975,Zimmerman,1977,Fick,1978,Harada,1982),乙烯萌发混合物,2-氯乙基-次磷酸可促进刚收获的栽培向日葵种子的萌发,赤霉酸(GA_3)和苯甲基腺嘌呤也有同样的效果(Kumar和Sastry 1974,1975),去除种壳也可促进萌发(Kumar和Sastry 1974,1975,Harada,1982)。本研究的目的是比较野生向日葵种种子的几种萌发方法,从而确定一种简单又有效的程序。
Seeding dormancy hindered the study of sunflower species and their application in breeding programs for improved cultivated sunflower (Helianthus annuus L.). Several seed treatments were tested to determine their efficiency in breaking down the intense seed dormancy system of many wild sunflower species. The first treatment, called complete treatment, involves multiple mechanical scratches of the seeds, soaking in a 100 mg / L gibberellic acid solution for 1 hour and removing the seed coat. Other treatments are the simplification of the procedure and the complete application of three seed treatments of gibberellic acid and 2-chloroethyl-hypophosphoric acid. The results showed that removal of the seed coat and seed coat was most effective, increasing the germination rate of many species (including the extremely hard-to-emerge annual desert species) to more than 90% and placing the multiple-pricked seeds 100 mg / L red Smear acid soak for 1 hour to promote the germination of certain species. Immersion of intact seeds in 100 mg / L gibberellic acid for 1 hour or in 500 mg / L 2-chloroethyl-hypophosphorous acid for 1 hour did not promote germination. Germination of intact seeds in 100 mg / L or 100 mg / L gibberellic acid solution for 10 days can promote germination, but the formation of abnormal seedlings, although the complete treatment is complicated, but its germination rate is high and the variation among materials is minimal, therefore it is recommended Complete treatment as the best method. Many crop breeders are concerned with the use of wild sunflower as a genetic resource for improved cultivation of sunflower (Helianthus annuus L.), but a strong seed dormancy system hinders the utilization of these species. The dormancy systems of seeds of different intensities exist in all wild species, but the annual desert species H.deserficola Heiser, H.anomalus Blake and H..hiveus subspecies fephrods (A.GrAy) Heiser (Heiser et al., 1969) are particularly strong . These xerophytes are of particular importance as drought tolerant genetic resources. According to evil, some perennials are also very dormant (Heiser, 1916). To ensure the germination of wild sunflower seeds well, several methods have been applied. Heiser et al. (1969) reported that the most effective method of planting seeds in pots is to seed the seeds at different temperatures (including freezing and thawing) each time they move out of the house for 3 weeks to 1 month. This method can promote germination, but rarely more than 50%, and the one-year drought species. Other methods have also been applied to the xerophytes, including alternation of wetting and drying, washing with water several times, and soaking seeds, but the germination rate is extremely low at 10%. The ethylene germination mixture, 2-chloroethyl-hypophosphorous acid, can promote the germination of freshly harvested sunflower cultivated seeds according to the study (Kumar and Sastry, 1974, 1975, Zimmerman, 1977, Fick, 1978, Harada, (GA 3) and benzyladenine (Kumar and Sastry 1974, 1975), and removal of the seed coat can also promote germination (Kumar and Sastry 1974, 1975, Harada, 1982). The purpose of this study was to compare several germination methods of wild sunflower seeds to determine a simple and effective procedure.