猬实种子休眠特性研究

以国家三级保护植物猬实果实为试验材料,应用扫描电镜和石蜡切片进行形态解剖观察,通过吸胀和果皮胚乳抑制物测试等方法探讨了休眠原因,并采用硫酸、赤霉素处理及低温层积处理进行了打破休眠的试验.结果表明:(1)猬实具有坚硬厚实的果皮,机械束缚是休眠的主要原因;(2)胚乳中含有萌发抑制物质,沙藏或赤霉素处理可有效解除其生理休眠;(3)打破猬实休眠的最佳方法为:浓硫酸处理15 min,并用400 mg·L-1赤霉素处理,或仅用4 ℃沙藏30 d.     

赤霉素处理打破虎眼万年青休眠的研究

试验以虎眼万年青子鳞茎为材料,采用二因素随机区组设计,对其进行不同温度、不同赤霉素浓度的打破休眠试验,探讨赤霉素和温度对打破虎眼万年青休眠效果,以确定打破虎眼万年青子鳞茎休眠的最适赤霉素浓度和适宜温度。结果表明:赤霉素浓度为100~150 mg/L时打破休眠的效果好并且长势好,低温结合赤霉素处理对打破虎眼万年青休眠的效果更好,能极显著地提高虎眼万年青子鳞茎的出苗率。     

不同方法打破青菜种子休眠效果试验

为探明打破青菜种子休眠的有效方法,作者以上海申耕农业发展有限公司的杂交青菜品种青山种子为试验材料,开展了温汤浸种、低温处理和赤霉素溶液浸种打破青菜种子休眠效果的比较试验。试验结果表明,4℃低温处理7 d以上和用80 mg/kg赤霉素溶液浸种4 h均可有效打破青菜种子的休眠,种子发芽率达90%以上,超过国家标准85%的要求。     

快速处理苹果砧木种子法

我们根据赤霉素、活力素具有打破休眠、促进生长的功能,进行了赤霉素、活力素处理砧木种子的试验,取得较好效果,缩短了种子层积时间30—50天。试验于1991—1992年在偃师县缑氏乡扒头村进行,设赤霉素、活力素和赤霉素+活力素三个处理,砧木种子为八棱海棠。 1、用500ppm赤霉素浸种10—15小时,而后     

不同处理对海棠种子发芽的影响

以八棱海棠的种子为试材,研究快速打破海棠种子休眠,提高发芽率的最佳处理方式。分别进行了不同浓度的赤霉素溶液以及不同时长的浸泡、温度不同的蒸馏水以及不同时长的浸泡、低温层积等处理。结果表明:赤霉素和温水浸种处理不能完全打破八棱海棠种子的休眠,但处理之后的种子发芽率在一定程度上有所提高。赤霉素处理对打破休眠的最佳浓度是200 mg/kg,发芽率可达50.25%。总体来说浸泡时长对打破八棱海棠种子休眠结果不明显。而打破八棱海棠种子休眠最佳处理的是低温层积,其打破休眠的时间是60 d,发芽率达到86%。     

不同浓度赤霉素对黑籽南瓜种子发芽率的影响

黑籽南瓜主要作为黄瓜嫁接的砧木,但因其发芽率普遍较低,尤其新种子发芽率更低.试验通过使用不同浓度的赤霉素处理打破其休眠,提高其发芽率,并以清水作对照,从而找出打破其休眠的最适宜的赤霉素的浓度.     

毛桃种子发芽试验

毛桃是桃的优良砧木。一般其种子必须经过低温(层积)处理才能正常萌发。夏季采收的毛桃种子,如果不进行任何处理立即播种,均不能正常萌发。从我们对打破毛桃种子休眠,促使发芽的试验结果表明,毛桃种子的休眠与坚硬的内果皮、致密的种皮以及种皮内含有的抑制发芽的物质有关。剥去种皮,种子能正常发芽,起到层积处理的作用。赤霉素能解除和部分解除种皮对种子的     

解除瓠瓜种子休眠技术的研究

系统地研究了打破瓠瓜充分成熟种子休眠的技术,结果表明,采后约50天其休眠现象可自然解除,磕种处理、1 500mg/L赤霉素液和0.6%H2O2液浸种均可有效打破瓠瓜种子的休眠现象.     

不同处理对荠菜种子休眠与萌发的影响

以野生荠莱种子为试验材料，研究了3种不同处理方法对种子休眠与萌发的影响。结果表明：GA3（赤霉素）、6-BA（6-苄基嘌呤）和低温处理均能有效的解除荠菜陈种子的休眠，6-BA的处理效果优于G氏，但单独使用GA3或6-BA对荠菜新种子的解除休眠不起作用。低温能解除荠莱新种子的休眠（平均发芽率84．07％）。随着处理天数的增加，荠菜种子发芽率明显提高。     

不同处理对荠菜种子休眼与萌发的影响

以野生荠菜种子为试验材料,研究了3种不同处理方法对种子休眠与萌发的影响.结果表明:GA3(赤霉素)、6-BA(6-苄基嘌呤)和低温处理均能有效的解除荠菜陈种子的休眠,6-BA 的处理效果优于GA3,但单独使用GA3或6-BA对荠菜新种子的解除休眠不起作用.低温能解除荠菜新种子的休眠(平均发芽率84.07%).随着处理天数的增加,荠菜种子发芽率明显提高.     

Dormancy and germination in Rosa multibracteata Hemsl. & E. H. Wilson

Most of the achenes produced by Rosa multibracteata Hemsl. & E. H Wilson are dormant on maturity and require pretreatment to stimulate germination. To investigate the mechanism of dormancy and to develop effective methods of improving germination, roles of the pericarp, testa, and embryo of R. multibracteata in regulating dormancy were studied by investigating the effect of different pretreatments on germination. The effects of temperature and water stress were also tested with achenes treated by warm plus cold stratification. In freshly harvested achenes, pericarps are permeable and the embryo fully developed, which eliminates the possibility of physical, morphological, or morphophysiological dormancy. Germination percentage remained low (<5%) despite softening the pericarp or even removing it fully. However, fully removing the testa improved germination significantly (39%), indicating the possible presence of germination inhibitors in the testa. Dry storage, scarification with sulphuric acid (H₂SO₄), and warm stratification proved ineffective by themselves but when combined with cold stratification, improved germination and shortened the cold stratification period needed to break dormancy. Dry storage for 68 weeks followed by cold stratification for 16 or 24 weeks resulted in maximum germination (72–79%) among all the treatments. In achenes scarified with H₂SO₄, germination increased with an increase in the duration of cold stratification. Neither gibberellic acid (GA₃) nor ‘smoke water’ (water through which smoke had been bubbled for 2 h) had any positive effect on germination even on seeds that had been mechanically scarified or stratified. Both high temperature and water stress lowered germination in achenes treated with warm plus cold stratification. Our results suggest that R. multibracteata achenes have an intermediate physiological dormancy, and that dry storage for 68 weeks followed by cold stratification for 16 or 24 weeks is the best method for propagating R. multibracteata from seed.     

Methods to break seed dormancy in Cyclocarya paliurus (Batal)Iljinskaja

Cyclocarya paliurus is native to China and is the sole species in its genus. However, the seeds remain deeply dormant for 2 years in their natural environment. We tested different pretreatments of chemical scarification and exogenous application of gibberellic acid (GA₃) for efficacy in breaking dormancy and speeding germination. In contrast to scarified seeds, non-scarified seed did not germinate, indicating that C. paliurus seeds have hard, impermeable seed coat dormancy. Exogenous application of GA₃ significantly enhanced germination of scarified seeds. Compared with seeds stratified in sand with water, the germination of seeds stratified in sand moistened with 400 ppm GA₃ for 60 days was significantly increased and germination rate was over 90% after 120 days. Analysis of variance indicated that both GA₃ concentration and stratification medium had significant effects on seed germination and final germination percentage. Germination was higher for longer stratification periods, but no significant difference in germination was observed after 90 days. These results suggested that C. paliurus seeds exhibit both exogenous and endogenous dormancy. A combination of chemical scarification and exogenous application of GA₃ alleviated seed dormancy in a relatively short period of time.     

Seed dormancy and germination of Michelia yunnanensis (Magnoliaceae)

Michelia yunnanensis Franch. is a Chinese endemic ornamental shrub with potential for greater utilization as a landscape and medicinal plant if propagation was less difficult. Seed development and breaking of seed dormancy were investigated to improve propagation of M. yunnanensis. No fresh seeds germinated when tested at the time of dispersal. Newly matured seeds of M. yunnanensis contained differentiated linear underdeveloped embryos that were physiologically dormant. The embryo/seed length ratio of M. yunnanensis was 0.15. Warm stratification did not break seed dormancy. Dormancy was broken by cold stratification at 4 °C but not by flowing water or nitrate. Embryos developed grew inside seeds during cold stratification at 4 °C. In newly harvested dormant seeds, embryos were 0.94 mm long and increased in length 139% before radicle emergence (germination). GA₃ substituted for cold stratification to break dormancy in seeds of M. yunnanensis incubated at 25 °C or 20/25 °C. Mature M. yunnanensis seeds exhibited intermediate complex morphophysiological dormancy. Optimal germination of non-dormant seed in terms of both germination percentage and rate occurred at 20/25 °C.     

变温及GA3 处理对辽东楤木种子解除休眠过程中代谢调控的影响

 研究在变温条件下GA₃对辽东楤木种子解除休眠过程和呼吸代谢途径关键酶(磷酸己糖异构酶、6-磷酸葡萄糖脱氢酶、6-磷酸葡萄糖酸脱氢酶、琥珀酸脱氢酶) 的活性变化。结果表明: GA₃经200 mg·L ^{- 1}的丙酮溶液浸泡种子12 h, 其α-淀粉酶活性和可溶性糖的含量显著提高, 均在第12天达到最大值;从层积开始可溶性蛋白含量就不断降低, 在第12天降到最低点; 种子在后熟过程中主要以糖酵解和三羧酸循环作为供能形式。在GA₃和层积变温处理过程中呼吸代谢途径关键酶的活性在第8天达到最大值, 表明磷酸戊糖途径的活化对解除种子休眠起到至关重要的作用。     

GA3对辽东楤木种子解除休眠中信号分子变化的影响

 研究了GA₃ 对辽东楤木种子在变温(每天高温13～15℃ 12 h, 低温0～4℃ 12 h) 层积条件下解除休眠过程中部分信号分子变化的影响。结果表明: 200 mg/L的GA₃ 丙酮溶液可以极显著促进辽东楤木种子萌发; 显著降低种子内源ABA 含量; 显著提高种子内源GA 含量、CaM含量和NADKase、质膜Ca^{2 +} -ATPase活性, 从而说明了信号分子参与并调节了辽东　木种子休眠解除这一过程。     

Effects of after-ripening,stratification and GA3 on dormancy release and on germination of wild asparagus (Asparagus acutifolius L.) seeds

Seeds of wild asparagus (Asparagus acutifolius L.) were treated and compared in this research to investigate seed dormancy class and level involved in this species. Four seed lots were compared: (i) freshly harvested seeds in 2007 (07Fr); (ii) freshly harvested seeds in 2008 (08Fr); (iii) after-ripened (AR) 2007 seeds dry stored in glass jars (ARg); (iv) AR 2007 seeds dry stored in paper bags (ARp). The 07Fr seeds were exposed to (1) chemical scarification combined with gibberellic acid (GA₃) levels (0, 200, 400, and 600 mg L⁻¹) and to (2) 28-day moist stratification at 5 and 23 °C, and two sequences of 5/23 °C combined with 0 and 400 GA₃ mg L⁻¹ levels, and (3) together to the 08Fr and AR seeds were exposed to 56-day moist stratification at 5, 23, or 5/23 °C. With the 08Fr and AR seed lots this last stratification treatment was combined with 0 or 800 GA₃ mg L⁻¹ levels. The dormancy depth of 08Fr (32% germination) was less than 07Fr seeds (2%). The latter after-ripened during dry storage and when stored in glass germinated more (47.5%) than in paper (12%). Stratification for 4 weeks was ineffective in improving germination of 07Fr seeds; when chemically scarified they did not germinate at all. The highest (nearly 70%) and the most rapid and uniform germination were observed for all the lots when they were warm stratified for 56 days. Warm stratification improved germination more than alternate temperature stratification, while cold stratification inhibited germination especially for the 08Fr and ARg lots, thus seeds seem not to have a morphological component to their dormancy. GA₃ only improved germination of 07Fr seeds, at a low rate. A. acutifolius seeds fit the characteristics of a non-deep physiological dormancy.     

GA3对杨梅叶片木质素水平及其相关酶活性和成花的影响

 ‘荸荠种’杨梅小年树花芽孕育初期, 苯丙氨酸解氨酶(PAL) 活性首先达到高峰; 之后多酚氧化酶(PPO) 活性出现高峰。花芽孕育盛期过氧化物酶(POD) 活性达到高峰, 且与木质素积累到最大值相一致。花芽发端期间, POD活性和木质素水平均降低。GA₃处理降低了花芽孕育期间PAL、PPO 和POD 的活性, 导致木质素合成滞缓, 抑制花芽发端和降低成花率。     

影响野生杏种子萌发的相关因素研究初报

试验以新疆野生杏的单株种子为材料,通过低温层积、机械去壳、去种皮及赤霉素处理等方法,研究不同处理对野生杏种子休眠及萌发的影响.结果表明:野生杏种子经过低温层积处理后,在一定时间内,随着层积时间的延长,发芽率也随之提高;低温层积处理40 d后野生杏种子开始萌发,100 d后发芽率可达90%;野生杏种子的种壳和种皮不同程度的抑制了种子萌发,去除种壳可使种子萌发提前,同时提高其发芽率;未层积的种子在去除种皮后用清水处理24 h,在25℃条件下,种子的萌发率达到80%以上,说明去除种皮能基本解除种子的休眠;一定浓度的GA3对野生杏种子的萌发具有促进作用.6号带壳种子与去壳种子的最适GA3浓度均为100mg/L,发芽率分别为86.7%、100%.而7号带壳种子的最适GA3浓度为300 mg/L,发芽率为70%.     

内源ABA和GA3对欧洲甜樱桃花芽自然休眠的调控

 以8年生欧洲甜樱桃为试材，采用液相色谱法分析了自然休眠期间花芽内源GA₃，和ABA含量变化及相关环境因子的影响。结果表明，休眠期间，花芽ABA含量呈先升后降的趋势，11月上句达顶峰。GA₃含量变化与其相反，休眠初期急剧下降，11月下旬达最低谷，休眠解除期间含量不断上升。ABA/GA₃随休眠加深而升高，随休眠解除而不断降低。低温5℃显著增加了GA₃含量，降低了ABA含量，使ABA降低和GA₃升高的时间提前，较对照提早解除休眠。高温(20℃)则具有相反的作用，变温(5/20℃)处理对休眠解除有一定作用，但由于高温(20℃)对休眠解除的抵消作用，其破眠效果不如持续低温(50℃)处理明显。落叶前遮荫处理使GA₃ 含量稍有降低，但对ABA影响不大。长光周期处理促进了GA₃的合成，抑制了ABA的生成，从而抑制了休眠，而短光周期处理显著提高了ABA的含量，降低了GA₃ 的含量。     

低温与赤霉素处理对‘凤丹’种子萌发和幼苗生长的影响

研究了在容器栽培条件下,赤霉素(GA₃)与低温处理对促进‘凤丹’牡丹种子生根、萌芽和幼苗生长的效果,结果表明：GA₃能够促进种子生根,100～200 mg﹒L-1低浓度处理有利于提高生根率与生根质量;在一定范围内,延长低温处理时间促进种子萌发和幼苗生长;在低温足以打破上胚轴休眠时,较高浓度的GA₃对幼苗生长发育不利。综合分析不同处理对发芽率、发芽指数、苗高、叶片数、第1叶叶宽、茎长以及地上和地下部干质量等指标的影响,发现21 d和28 d低温分别结合100或200 mg﹒L-1 GA₃处理,最有利于种子萌发和幼苗生长。