聚乙二醇(PEG)浸种对茎瘤芥老化种子活力及其幼苗生长的影响

茎瘤芥品种‘永安小叶’老化种子经聚乙二醇(PEG)浸种后,其种子活力和幼苗生长与PEG浓度有一定的相关性,不同浓度PEG浸种后的茎瘤芥种子膜透性均降低,种子发芽率、发芽势、发芽指数和活力指数增大,幼苗根干重、茎干重和根长也均增大,幼苗叶片中丙二醛(MDA)含量降低。幼苗生长与种子活力的变化趋势一致,PEG浓度小于30%时呈增大趋势,大于30%时呈减小趋势,但均大于不做PEG处理的;幼苗叶片中MDA含量与种子膜透性变化趋势一致,PEG浓度小于25%时,呈降低趋势,大于25%时则呈升高趋势,但这些指标均低于不做PEG处理的。

固体基质引发提高黄瓜种子活力研究

以黄瓜品种南水1号、超市1号和南抗1号贮藏5a的陈种子为试材,研究不同固体基质引发对老化黄瓜种子活力的影响。结果表明:固体基质引发处理可以改善老化黄瓜种子的膜透性,减轻膜脂过氧化作用,提高种子活力,促进其萌发,蛭石和珍珠岩引发处理均可以不同程度地提高老化黄瓜种子的萌发率和萌发速度,降低种子浸出液的相对电导率、可溶性糖含量及丙二醛含量,提高SOD活性;椰糠引发处理的黄瓜老化种子萌发特性及生理指标与对照差异不显著。

Effects of Sunflower Artificial Aging on Seed Vigor and Physiological Characteristics

[Objective]The aim was to study the effects of sunflower artificial aging on seed vigor and physiological characteristics.[Method] The varieties of seed germination capacity,vigor of germination,germination index,vigor index,peroxidase（POD） activity,superoxide dismutase（SOD） activity and malondialdehyde（MDA） content for four sunflower germplasms such as＇SunM20＇,＇Deep Purple Minle＇,＇Da San Kui Hua 4＇and＇Ji Kui 24＇were studied under high temperature and high humidity conditions（100% RH,45 ℃） for different days（0 d,2 d,4 d,6 d,8 d,10 d）.[Result]The result showed that the germination capacity,vigor of germination,germination index,vigor index,POD activity,SOD activity declined gradually with the increase of seed aging days,whereas MDA content enhanced by degrees;The diggerences of resistance to artifical aging existed among the four accessions,＇SunM20＇was the most resistant one,and exhibited the strongest seed vigor,highest activities of two protective enzyme（POD,SOD） and lowest content of MDA at the uniform condition,moreover,the seed vigor and protective enzyme activities of＇SunM20＇changed slowest among the four materials during the aging process.[Conclusion]The distinct reduction of POD,SOD activities maybe the main reasons for the decrease of sunflower seed vigor at the artificial aging,and the gradual accumulation of a few MDA accelerated seeds aging.

Determination the Vigor of Rice Seed with Different Degrees of Aging with Ultraweak Chemiluminescence During Early Imbibition

用高灵敏度的单光子计数系统探测人工老化 (40℃ ,相对湿度 90 % ) 0、7、14和 2 1d的水稻种子吸胀初期的超弱化学发光强度变化 ,首次观测到水稻 (OryzasativaL .)种子吸胀初期超弱化学发光强度与其老化程度有关。加水激活水稻种子的超弱化学发光 ,其强度依赖于种子的老化程度。实验结果表明水稻种子的人工老化时间越短 ,则吸胀初期 (2 0～ 30min)超弱化学发光的强度越强 ,萌发率越高。水稻种子萌发率与超弱化学发光强度呈显著正相关。观测水稻种子吸胀初期超弱化学发光强度的变化可望成为检测种子老化程度的一种快速、简便、无损伤的新方法。

Relationship of Ultraweak Luminescence Intensity with Physiological Metabolism of Maize Seeds during Artificial Aging

The seeds of maize （Zea mays L.） variety Zhengdan 958 were used to study the change of ultraweak luminescence （UWL） intensity and its relationship with seed vigor, relative electric conductivity and ATP content during artificial aging. The results indicated that the germination percentage, germination potential, germination index, UWL intensity and ATP content decreased gradually, while the relative electric conductivity increased with the prolongation of artificial aging. The correlation analysis showed that UWL intensity was significantly positively correlated with ger- mination percentage, germination potential, germination index and ATP content, while significantly negatively correlated with relative electric conductivity. It was concluded that UWL was closely related to the energy level symbolized by ATP content, and as a fast nondestructive physical indicator with better sensitivity, it could be applied into the study of seed vigor nondestructive testing.

Effects of Artificial Aging on Seed Vigor and Ultraweak Luminescence of Wheat Seeds

In order to ascertain the effect of artificial aging on ultraweak lumines- cence （UWL） and the correlation between UWL and seed vigor, and explore a new way of seed vigor non-destructive testing, seeds of wheat variety ‘Jimai 22＇ were used to study the change of UWL intensity and its relationship to seed vigor and ATP content during artificial aging. The results showed that with the extension of artificial aging time, the germination percentage, germination potential, germination index, UWL intensity and ATP content decreased gradually; after artificial aging for 48 h, they were reduced by 19.19%, 34.34%, 38.78%, 27.77% and 13.84%, re- spectively, compared with CK. Correlation analysis indicated that the UWL intensity was significantly positive correlated with germination percentage, germination poten- tial, germination index and ATP content. It was concluded that UWL as a fast, non- destructive and sensitive detection method could be applied in the study of seed vigor non-destructive testing.