Ethephon Promotes Germination of Echinacea angustifolia and E. pallida in Darkness

Seeds from five lots each of Echinacea angustifolia DC, and E. pallida (Nutt.) Nutt. were germinated in a growth chamber in light (40 μmol·m(-2)· s(-1)) or darkness at 25 °C for 16 to 20 d after soaking in 1 mM ethephon or water for 10 min, or moist stratification at 4 - 6 °C for two weeks. Either light or ethephon promoted seed germination of E. angustifolia and E. pallida, in comparison with darkness in nine of ten lots. Ethephon in the dark had similar or greater germination percentages than water with light. Ethephon with light improved germination in three of ten lots compared with ethephon in the dark. The effect of cold, moist stratification in comparison with darkness varied by seed lot. Five lots of E. purpurea (L.) Moench were tested; however, no treatment differences were measured. The finding that ethethon promoted E. angustifolia and E. pallida seed germination in darkness could be useful in the cultivation of these two species. Chemical name used: 2-chloroethylphosphonic acid (ethephon).     

The effect of seed source, light during germination, and cold-moist stratification on seed germination in three species of Echinacea for organic production

Organic production of one of the most popular botanical supplements, Echinacea, continues to expand in the U.S. Echinacea seeds typically show a high degree of dormancy that can be broken by ethephon or gibberelic acid (GA), but these methods are currently disallowed in organic production. In order to determine the efficacy of non-chemical seed treatments, we evaluated the effect of varying seed source and supplying light, with and without cold-moist stratification, on seed germination of the three most important medicinal species of Echinacea, E. angustifolia DC, E. purpurea (L) Moench, and E. pallida (Nutt.) Nutt. Treatments included cold-moist stratification under 24 h light, 24 h dark, and 16/8 h light/dark to break seed dormancy. We found that germination was greater in the E. purpurea and E. pallida seeds from a commercial organic seed source compared to a public germplasm source. When seeds were not cold-moist stratified, 16-24 h light increased germination in E. angustifolia only. Echinacea angustifolia, E. purpurea, and E. pallida seeds that were cold-moist stratified under 16-24 h of light for 4 wk had a significantly greater percentage and rate of germination compared to seeds germinated in the dark. Therefore, cold-moist stratification under light conditions is recommended as a method to break seed dormancy and increase germination rates in organic production of Echinacea.     

双氧水对茄子种子萌发的影响

新采收的茄子种子因休眠作用影响种子的萌发,会出现幼苗参差不齐的现象．影响了农业生产。为了打破种子的休眠,以南京市蔬菜科学研究所培育的黑骠茄子和日本砧木品种托鲁巴姆为试验材料,研究了双氧水对茄子种子发芽势、发芽率和发芽指数的影响。结果表明,在25℃下,双氧水浸种可以显著提高茄子种子的发芽势、发芽率和发芽指数,而且在低浓度处理下效果较好,随着浓度的提高,处理效果逐渐降低,当双氧水浓度达到1．2％时已基本没有效果,以0．3％双氧水浸种3h,可以使发芽势、发芽率和发芽指数达到最高。     

白菜种子萌发的热抑制现象及其与细胞壁降解酶的关系

为了探讨白菜种子萌发热抑制的机制,以新收获的白菜种子为材料,研究了种子萌发对不同温度的响应,后熟、冷层积和植物激素处理对种子萌发的作用,以及种子萌发和不同处理与细胞壁降解酶之间的关系。结果表明,当萌发温度 ≥ 20 ℃时,种子的萌发率显著降低,热抑制的种子不表现次生休眠。后熟、层积和GA₃处理能有效地降低种子萌发的热抑制;相反,ABA处理则增强种子萌发的热抑制。种子萌发过程中内切–β–甘露聚糖酶、β–甘露糖苷酶和α–半乳糖苷酶的活性增加。与新收获的种子相比,后熟、层积和GA₃处理增加上述3种酶的活性;ABA处理增加内切–β–甘露聚糖酶的活性,但不影响β–甘露糖苷酶和α–半乳糖苷酶的活性。在不同温度下吸胀48 h的种子的内切–β–甘露聚糖酶和α–半乳糖苷酶的活性变化与随后种子的萌发没有直接关系。说明新收获的白菜种子具有明显的萌发热抑制,这种特性能被后熟、层积和GA₃处理以增强细胞壁降解酶活性的方式有效地解除。     

茗葱种子萌发的生态学特性研究

以茗葱种子为试材,对其种子萌发生态特征进行研究。结果表明:茗葱种子含水量达7.97%;四唑(TTC 0.1%)染色测种子的生活力为(80.8±2.3324)%;不同温度下茗葱种子发芽进程缓慢,20℃为发芽最适温度,发芽率达(84.00±6.00)%,与其它温度差异显著;光照与否对种子的发芽率及发芽势不具有显著差异。     

种衣剂与赤霉素对茄子种子发芽及幼苗生长的影响

内部激素和革质种皮共同作用导致茄子种子休眠,影响萌发。为了寻找一种适用于茄子种子处理的操作方法,研究种衣剂和赤霉素的相互作用,用200、400、600、800、1 000 mg·L-1的赤霉素溶液预处理茄子的包衣种子和未包衣种子,并测定相关发芽指标和幼苗生长指标。结果表明,用600 mg·L-1的赤霉素溶液预处理茄子种可以显著提高包衣种子活力,增强幼苗在逆境环境下的抵抗力,而对未包衣种子效果有限。这表明添加适当赤霉素的种衣剂处理才能有效提高茄子种子活力,促进种子萌发,达到出苗迅速整齐的目的。     

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%.     

洋葱鳞茎栽植时期对种株生长发育和种子产量及质量的影响

 研究了9月20日、10月10日、10月30日和11月20日4个洋葱鳞茎栽植时期对种株生长发育和种子产量及质量的影响。结果表明,9月20日栽植,虽越冬前植株营养生长旺盛,但翌年春生长势减弱,植株早衰,影响生殖生长;11月20日栽植,则翌年春植株营养生长受抑制,也不利于抽薹、开花、结实;10月10日和10月30日栽植,植株营养生长旺盛,花薹粗壮。种子收获时,9月20日、10月10日、10月30日和11月20日4个栽植日期的单株种子产量分别为8.98、13.74、14.56和11.46g,千粒质量分别为3.86、4.02、4.07和3.95g。此外,不同栽植时期采收的种子发芽势和发芽率也差异显著,各处理的种子发芽势依次为80.2%、90.9%、95.1%和86.2%。表明山东地区洋葱鳞茎的适宜栽植期为10月10～30日。     

Seed Biology of the Weed Maryland Meadowbeauty (Rhexia mariana L.) in Blueberry (Vaccinium spp.)

Studies were conducted at three locations across the North Carolina coastal plain region to determine sexual reproductive potential, seedbank density, frequency of seed dormancy, and effect of temperature on Maryland meadowbeauty seed germination. Seed capsule density ranged from 500 per m² to 1124 per m² across locations. Each capsule contained an average of 74 seeds. Seeds germinated only in the 35/20 °C temperature regime, which represents the hottest month (August) of the growing season in southeastern North Carolina. Total number of germinated seeds differed across locations and ranged from 30% to 57%. The percent (average) of viable (66) and nonviable (26) meadowbeauty seeds was not different across locations. Relative germination and seed dormancy percentages were calculated based on the number of viable seeds. The percent relative germination and seed dormancy were different across locations and ranged from 47% to 86% and 14% to 55%, respectively. The highest number of germination resulted from 90 days of stratification. On average, 27 seeds germinated among soil samples, which is equivalent to 989 seeds per m². The data indicate that the populations of meadowbeauty in blueberry fields have the potential to sexually reproduce and contribute 5 × 10⁶ to 1.1 × 10⁷ seed capsules/ha and 3.7 × 10⁸ to 8.3 × 10⁸ seeds/ha of infestation. Freshly mature seeds can germinate and contribute 1.79 × 10⁸ to 7.14 × 10⁸ seedlings/ha in the year the seeds are produced and 5.18 × 10⁷ to 4.4 × 10⁸ seeds/ha can be dormant and incorporated into the seed bank on an annual basis. Approximately 9.89 × 10⁶ seeds/ha are dormant and viable in the soil and have the potential to germinate following adequate stratification.     

匙叶翼首草不同海拔地区种子活力的研究

采用裂区设计研究了不同海拔地区匙叶翼首草种子在不同处理下的种子活力及最佳的发芽温度、光照等条件,为了大田生产的种子发芽和育苗提供理论指导。结果表明:在不同的处理下,不同海拔地区的翼首草种子经过50℃水浴处理20 min,在暗培养箱25℃恒温下培养,都能极好地提高其种子的发芽率、发芽势、发芽指数等指标;同时,在发芽与育苗试验中选用甘南碌曲双岔海拔较低地区的翼首草种子,种子的活力最高,引种驯化与人工栽培更易于成功。     

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.     

瓜类蔬菜种子休眠与萌发研究进展

破除瓜类蔬菜种子休眠的技术有机械损伤种皮、植物激素处理和化学药剂处理。多数休眠的瓜类蔬菜种子在特殊条件下能够发芽。瓜类蔬菜种子休眠的原因有胚休眠、种皮的障碍、发芽抑制物质的存在和激素不平衡等几个方面。     

慈姑种子发芽特性研究

以野生型慈姑巢湖野慈、棠梨店慈和栽培型慈姑浙江农大慈、南宁家慈为试材,从贮藏方法、光照、温度等方面对慈姑种子萌发特性进行了初步探讨。结果显示:慈姑种子需要浸水贮藏,低温水浸贮存更有利于种子萌发,干燥贮存导致种子不能萌发;光照对慈姑种子萌发有明显促进作用;慈姑种子最适发芽条件为25℃、12h/12h(L/D);不同基因型慈姑种子的发芽率存在差异,野生型慈姑明显高于栽培型慈姑。     

打破新鲜蛇莓种子休眠方法的研究

以贵州省各地引种的不同蛇莓为试材,通过蒸馏水、自来水、浓硫酸、盐酸、氢氧化钠、洗洁精、光照、40℃保温、无菌培养、含生长素和多种元素的培养基培养、摩擦除去部分果皮等方法打破蛇莓种子休眠,研究其种子萌发因素及休眠原因。结果表明:蛇莓种子存在较明显的休眠现象和多种休眠原因,但用加热、氢氧化钠、光照等条件组合办法能打破种子休眠,发芽率可达90%,种子休眠原因有待进一步研究。     

赤霉素和脱落酸对番茄种子发芽的生理调控──文献综述

介绍番茄种子发育过程中，种子发芽力和抗脱水力形成，浅休眠和胎萌等现象的基础上，着重讨论了ＧＡ与ＡＢＡ在番茄种子浅休眠形成、抑制胎萌方面的作用以及对渗控处理和发芽过程中种子水分关系、种胚生长、ＤＮＡ复制、胚乳弱化等的生理调控机制。     

外源水杨酸和甜菜碱对NaCl胁迫下茶花凤仙种子萌发的影响

以茶花凤仙(Impatiens balsamena)种子为试材,采用双层滤纸法,研究了100 mmol·L^-1NaCl胁迫条件下,外源SA(0.5、1.0、1.5、2.0 mmol·L^-1)和GB(0.4、0.8、1.2、1.6 mmol·L^-1)浸种预处理对茶花凤仙种子萌发及幼苗生长的影响,以期明确茶花凤仙种子萌发期2种外源物质对NaCl胁迫的缓解效应,降低NaCl胁迫对茶花凤仙的伤害。结果表明:NaCl胁迫显著抑制了茶花凤仙种子的萌发,发芽率、发芽势、发芽指数、活力指数、胚芽长、胚根长和苗鲜质量均显著下降,平均发芽时间显著延长;1.5 mmol·L^-1SA和0.8、1.2 mmol·L^-1GB对NaCl胁迫下茶花凤仙种子萌发和幼苗生长具有明显促进作用,而SA和GB浓度过高或过低则对NaCl胁迫的缓解效应下降,甚至加重盐害。利用隶属函数综合评价得出,100 mmol·L^-1NaCl胁迫下,1.5 mmol·L^-1SA和0.8 mmol·L^-1GB对茶花凤仙种子萌发及幼苗生长的综合调控效果较好,且0.8 mmol·L^-1GB对NaCl胁迫的缓解效果优于1.5 mmol·L^-1SA。     

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.     

野生山楂种子休眠特性及破除方法探讨

以不同类型野生山楂种子为试材,观察了冷藏、常温处理对野生山楂种子萌发情况的影响,以期探讨山楂种子休眠的原因,寻找破除种子休眠的处理方法。结果表明:山楂种子的休眠性与种子种仁无关,与种壳有关,浓硫酸处理山楂休眠种子的最佳时间为50 min。     

苦豆子浸提液对“比斜克其”甜瓜种子萌发及幼苗生长的影响

本试验以新疆南疆地区特色甜瓜——“比斜克其”作为材料,通过培养皿滤纸法用苦豆子不同部位(叶片、茎秆、豆荚和种子)浸提液对“比斜克其”种子进行处理,分别测定种子发芽和幼苗生长情况。试验结果表明,对照组种子萌发率、发芽势和发芽指数均大于苦豆子处理组,其中种子浸提液处理的萌发率、发芽势和发芽指数等指标均小于其他4个处理。对照组幼苗的平均胚轴长度、平均主根长度、平均侧根数目、平均鲜质量和平均干质量均小于苦豆子处理组,其中茎秆浸提液处理的胚轴长度、主根长度、侧根数目以及鲜质量均大于其他处理组。因此苦豆子植株不同部位浸提液对“比斜克其”种子萌发具有抑制作用,其中种子浸提液的抑制作用最强;但对“比斜克其”幼苗及根系生长均具有促进作用,其中茎秆浸提液促进作用最强。因此不建议将苦豆子作为底肥在“比斜克其”播种之前施用,而应在种子萌发之后作为追肥施用。     

盐分胁迫对园林植被黑麦草种子萌发的影响

用不同浓度的单盐NaCl和混合盐溶液,分别处理盐地黑麦草种子,以研究不同盐分处理对盐地植物种子萌发的影响,并初步探讨盐地植物种子在盐敏感区间及其上、下限区间内,对种子萌发率和萌发恢复率的影响.结果表明:在萌发盐敏感区间上限,随着盐浓度的增加,种子萌发率迅速降低;在萌发盐敏感区间下限内,种子萌发率与对照无差异;敏感区间内,单盐和复合盐处理的种子,萌发率表现不一致.盐地黑麦草种子在蒸馏水中的萌发率最高,单盐NaCL对种子萌发的抑制作用大于混合盐溶液;盐胁迫处理7 d后,未发芽的种子转至蒸馏水中,除高浓度NaCL溶液处理外,其他处理总萌发率都达到80%以上,表明盐胁迫下种子仍保持较高萌发潜力.