不同基质和覆盖处理对杜鹃种子萌芽及成苗的影响

为获得高效的杜鹃育苗方法,以杜鹃花‘紫鹤’和‘粉鹤’自交种子为试材,研究了不同基质和覆盖处理对杜鹃花种子萌发、成苗和实生苗形态建成的影响。研究结果表明:以未发酵的玉米秸秆粉末作为播种基质不能使杜鹃花种子发芽和形成实生苗;以园土与干苔藓混合物和园土与棉籽壳混合物作为播种基质仅有少量种子发芽,不利于实生苗的生长;以蛭石和蛭石与干苔藓混合物作为播种基质的杜鹃发芽率和成苗率分别可达到65.33%~81.33%和62.67%~78.67%,但不利于杜鹃花实生苗的形态建成;以草炭和草炭与干苔藓的混合物作为播种基质能显著促进杜鹃花种子的萌发和成苗形成,且杜鹃花实生苗生长发育健壮;覆盖处理则降低了杜鹃花种子的发芽率。     

Maximizing seed germination in two Acacia species

Revegetation of disturbed land, particularly in arid environment, is often hindered by low seedling establishment. Information on seed biology and germination cues of valuable species is lacking. We investigated seed germination of two Acacia species (Acacia tortilis (Forsk.) Hayne and Acacia oerfota (Forssk) schweinf), required for nitrogen fixation and rehabilitation of arid and semi-arid areas.(four pre-germination seed treatments were applied in order to find the best treatment in germinating acacia species. The medium was L2 and three replicates were used. Seeds pre-treated with sand paper and also with H2SO4 and then H2O2 had the highest germination percentage in both species. The lowest germination percentage resulted from soaking seeds in water for 48 h followed by soaking in H2SO4 for A. oerfota and from soaking in water for 24 h for A. tortilis. Because the use of sand paper is difficult and time consuming, we recommend pre-treatment of A. tortilis and A. oerfota seeds with H2SO4 and H2O2 before planting. Our study results are significant for conservation agencies with an interest in optimizing germination in arid zones for rehabilitation and reforestation.     

Effects of variation in seed sources and pre-sowing treatments on seed germination of Tamarindus indica: a multi-purpose tree species in Bangladesh

We investigated the morphology and germination of Tamarindus indica seeds in order to discover the effects of variation in seed sources and pre-sowing treatments on germination. The experiment was carried out in the nursery of the Forestry and Wood Technology Discipline, Khulna University, Bangladesh. Seeds were collected from different but healthy trees from various locations in Bangladesh and subjected to four pre-sowing treatments, i.e., control, immersion in cold water (4°C for 24 h), immersion in hot water (80°C for 10 min) and scarification with sand paper. Seed germination was carried out in poly-bags with a mixture of topsoil and cow dung in the ratio of 3:1. The average length of the fresh seeds was 1.35±0.26 cm, their width 1.07 ±0.20 cm and thickness 0.69±0.11 cm. The results revealed that pre-sowing treatments affected the germination process of seeds, which significantly increased the germination percentage with the cold water (81.67%) and scarification with sand paper (82.33%) treatments, compared with those in the control (58.33%) and hot water treatment (59.00%). In all treatments germination started on average within 5 to 7 days after the start of the treatments and were completed from 13 to 19 days later. The greatest success in germination (82.33%) was found in scarification with sand paper, followed with 81.67% in the cold water treatment. The results of analyses of variance (ANOVA) showed significant differences (p<0.05) in germination closing dates, seed germination periods and germination percentages among the treatments but no significant difference among seed sources. However, the effect of the interaction between seed source variation and pre-treatment differed significantly in seed germination closing dates and germination percentages. We recommend cold water treatment (submersion of seed at a temperature of 4°C for a 24-h period) for seed germination of T. indica in rural Bangladesh.     

Effect of different seed treatments on dormancy breaking and germination in three species in arid and semi-arid lands

Seeds of many woody plant species have one of several types of dormancy. They do not germinate unless specific environmental signals are in place or events occur. This study was conducted to evaluate the effects of scarification treatments on seed dormancy and germination of Acacia nilotica (L.) Willd. ex Del., Prosopis juliflora (Sw.) DC. and Dodonaea viscosa (L.) Jacq. The following treatments were applied: T1, untreated seed (control); T2, sulphuric acid (97%) for 45 min; T3, boiling water for 5 min. The seeds were cultured on a Murashige and Skoog (MS) medium after sterilization. The responses of seeds to treatments were compared with each other and with the control treatment. Germination was observed daily for a 30-day period. Results indicated positive responses to treatments, while impermeable seed coats may be responsible for low germination rates in intact seeds as seen experimentally in the untreated control. The highest germination was obtained for P. juliflora and D. viscosa acid-scarified seeds (80.8%-90.8%) and for scarified seeds of A. nilotica (50.2%) boiled in water. The germination indices, i.e., final germination percentage (FG), mean daily germination (MDG) and germination rate (GR), were significantly affected by treatments and species (p<0.01).     

银叶金合欢种子萌发特性研究

为优化银叶金合欢（Acacia podalyriifolia）种子处理方式,提高其种子萌发率。文章采用剪破种皮、热水、无水酒精、氢氧化钠溶液和浓硫酸浸种等处理,并测定其萌发特征。结果表明：各处理种子发芽势、发芽率均显著高于对照（P<0.05）,其中剪破种皮处理发芽势为84.6%,发芽率为87.3%;不同水温处理下,热水90℃处理3 min时发芽势、发芽率均最高,达到58.0%和61.0%;无水酒精和氢氧化钠浸种处理对银叶金合欢种子发芽势和发芽率有较显著影响,但随处理时间的延长,发芽势和发芽率无明显变化;浓硫酸浸种5 min时发芽率最高,达64.0%;综合考虑处理效率和安全性等因素,在生产上宜采用90℃热水恒温浸种3 min或无水酒精浸种90 min处理。     

Effect of water-spray cooling treatment in a Douglas-fir seed orchard on seed germination

Overhead-cooling treatment used to delay flowering produced non-significant effects on germination capacity, germination rate, germination value, and abnormal germination of seeds from a 13-year-old Douglas-fir [Pseudotsuga menziesii (Mirb.) Franco] seedling seed orchard. The percentage of variation accounted for by cooling treatment ranged from 0.0 to 1.0%. In contrast, variation among trees within treatments ranged from 28 to 46%. These effects were significant, indicating that each tree has an individual germination pattern. The temporal delay of reproductive phenology caused by temperature manipulation as a result of the cooling treatment was judged to be within the species' biological limits.     

聚乙二醇模拟干旱对三种木麻黄种子萌发的影响

为研究木麻黄Casuarinaceae.种子苗困难地造林,以木麻黄为试验材料,用不同渗透势浓度的聚乙二醇(PEG-6000)模拟干旱胁迫,探讨干旱胁迫对木麻黄种子发芽率、发芽势、胚轴和胚根长度及发芽指数、活力指数的影响。结果表明,不同浓度PEG胁迫处理均降低了种子的发芽率,延缓了木麻黄种子萌发进程;种子的发芽率、发芽指数和活力指数均随胁迫强度的增加呈明显下降趋势。当-1.20 MPa的PEG胁迫处理的种子在试验结束时仍未能萌发,表明-1.20 MPa是木麻黄种子萌发的临界水势。当PEG浓度为150 g/L时,三种木麻黄幼苗的胚根最长,且当PEG浓度为100 g/L时,三种木麻黄胚根长度长于对照组,但差异不显著,说明高于-0.40 MPa的水势有利于木麻黄种子胚根的生长。木麻黄幼苗苗高生长则是随着PEG浓度的升高而逐渐减缓。通过比较得知木麻黄种子抗旱性较强。     

杉木轻基质网袋容器育苗技术

文章介绍了应用轻基质网袋容器培育杉木壮苗的新技术。以沙壤土为基质进行播种,幼苗高5-8cm时移入轻基质网袋容器,基质以松皮粉60％＋锯末25％＋炭化锯末15％为宜,约1a生时85％以上苗木的地径大于0．50cm、苗高大于25cm,这时即可出圃造林。     

Metal Concentration in Plant Tissues of Jatropha curcas L Grown in Crude Oil Contaminated Soil

This study evaluated the heavy metal concentration in plant tissues of Jatropha curcas grown in crude oil contaminated soil in Asaba, Delta State, Nigeria, in 2010. The soil treatments included 0.0, 2.0 4.0, 6.0, 8.0, and 10.0% w/w oil contamination. The results showed a significant buildup of heavy metals including iron, zinc, cadmium, copper, manganese, lead, chromium, and nickel in contaminated soils when compared to the uncontaminated subplots (p ≤ .05). The amounts of metals observed in this study are below tolerable limits according to the Food and Agriculture Organization of the United Nations and Federal Environmental Protection Agency of Nigeria. A gradual accumulation and biomagnifications of these nonbiodegradable elements in plants can lead to dangerous or lethal levels with inherent health risks for humans and other organisms.     

铝处理对茶条槭不同种源种子发芽指标的影响

以吉林市、大连市和尚志市3个种源的茶条槭种子作为试验材料,研究铝元素对茶条槭不同种源种子有关发芽指标的影响.结果表明:在3个铝质量浓度处理下,3个种源种子的胚轴长差异不明显;大连种源在2.0g·L-1铝质量浓度处理后种子发芽率和活力指数达到了最高,而尚志市种源在3.5g·L-1铝质量浓度处理后发芽率达到了最高;在5.0...     

环境因素对风箱果种子萌发的影响

以风箱果自然成熟的种子为研究对象,对影响种子萌发的环境因素进行了研究.结果表明:种子属于需光性种子,光照能够促进种子萌发.在10～25℃条件下,种子均能萌发,以20℃发芽率最高[(78.33±1.67)%],萌发速度最快[(23.61±2.29)%];播种深度显著影响种子的出苗率(P<0.01),不覆土(O cm)出苗率高达(68.33±6.01)%;超过0.5 cm,出苗率显著降低,2 cm时出苗率为O;种子在土壤中萌发时,土壤的适宜含水量为40%,此时出苗最快[(15.44±0.15)%],出苗率最高[(51.67±1.67)%],幼苗的死亡率也较低[(16.67±8.82)%].自然条件下,温度不是种子萌发的限制因子,影响风箱果种子萌发和幼苗成功定居的关键因子是土壤含水量、光照以及播种深度.     

光照对15种豆科植物种子萌发的影响

对河西走廊15种豆科植物种子的萌发特性、萌发模式进行比较研究。结果表明:锦鸡儿一种在有光条件下的萌发率和萌发速率均显著高于黑暗中的萌发率和萌发速率;柠条锦鸡儿在黑暗下的萌发率和萌发速率均显著高于有光条件的;光、暗对其他物种萌发的影响没有差异。在有光条件下,柠条锦鸡儿、中间锦鸡儿和百脉根的萌发属于投机型;沙冬青、邦卡锦鸡儿、川西锦鸡儿和锦鸡儿一种种子的萌发属于中间型;黄华、苦豆子、苦参、树锦鸡儿、乌拉尔甘草和黄芪的种子萌发属于缓萌型;而甘草一种和苜蓿种子萌发属于低萌型。在黑暗条件下,中间锦鸡儿和百脉根的种子萌发属于投机型;中间型的与光照条件下相同;黄华、苦豆子、苦参和树锦鸡儿的种子萌发属于缓萌型,甘草一种、乌拉尔甘草、黄芪、柠条锦鸡儿和苜蓿的种子萌发属于低萌型。     

Effects of salinity and desalination on seed germination of six annual weed species

The effects of various salinities and desalination on seed germination of six annual glycophytes (Artemisia sieversiana, A. scoparia, Chloris virgata, Eragrostis pilosa, Chenopodium acuminatum and Chenopodium glaucum) were studied in Horqin Sandy Land, Inner Mongolia, China. NaCl solutions of five concentrations (0 mM, as the control, and 50, 100, 200 and 300 mM) were used for saline stress and desalination treatments. Increasing salinity significantly reduced germination percentages of A. sieversiana, A. scoparia, Ch.virgata and Ch. acuminatum, but had no effect on the germination percentages of E. pilosa. Lower salinity levels (50 mM) significantly increased germination percentage of Ch. glaucum. High salinity might be a precondition for germi- nation after desalination for five of the six species, excepting E. pilosa at NaCl concentration of 300 mM in comparison with non-primed seeds. Higher salinity (>200 mM) led to some specific ion toxicity and reduced seed viability of A. sieversiana. No specific ion toxicity but an osmotic effect limited the germination of other five species was observed The final germination percentages (salinity stress and desalination) of the six species showed three variations in comparison with the controls, namely, indiscrimination, stimulation, and reduction. Germination responses to salinity and desalination suggested that the six species were separated into three categories. Three species (A. sieversiana, Ch. virgata and Ch. acuminatum) showed similar germination responses to salinity with those of halophyte, but also showed a lower tolerance limit than most halophytes, although this was not always the case. A. scoparia and Ch. glaucum exhibited some ’salt stimulation’ in seed germination percentages after desalination, whereas E. pilosa did not show any obvious responseto salinity. Therefore, salinity usually induces dormancy of seeds with strong germination capacity in fresh water, but has few, or even positive, effects on seeds with strong innate dormancy.     

桉树人工林土壤环境对植物种子发芽和生长的影响

桉树(Eucalyptus)已成为我国华南地区很重要的速生阔叶用材树种,在海南已成为仅次于天然林、橡胶林的第三大森林生态系统.但随着大面积营造桉树人工纯林,生产上出现一些负面的影响,其社会效益和生态效益问题日益得到重视,其旺盛的生长是否会造成地下水的过量消耗,大面积的种植桉树人工林从而造成部分林地降低了地下水位、造成土壤的退化和影响林下植物种子萌发、植物的生长,林下植被的减少,土壤的退化等(蒋有绪,1992;王震洪等,1998;陈秋波,2001;林义辉,2001;项东云,2002;黄志宏,2003).     

麻疯树不同地理种源种子性状及苗期生长初报

麻疯树种子性状及育苗试验表明:参试的麻疯树不同地理种源的种子外观差异不大,长度、宽度、侧径变异系数分别为2.9%、4.6%和3.3%;千粒重差异相对较大,变异系数达到7.7%,千粒重表现比较好的种源有6号、12号、17号、20号,千粒重可作为麻疯树优良材料选择的指标;不同种源苗木生长差异较大,综合地径和苗高生长情况,总体生长表现比较好的种源有2号、4号、10号、13号、14号、19号,地径平均值为0.89~1.13 cm,苗高平均值为8.9~10.6 cm;6号、7号种源苗期个体分化比较大;苗高和地径之间相关关系符合幂函数方程y=9.595x0.3134(R=0.642 4);不同地理种源苗期耐寒性差异显著,耐寒性最强的为11号、13号和14号种源;其次为1~5号、10号、12号、20号种源;为了防止冻害,育苗地点应选在福建南部没有霜冻或霜冻时间比较短的地方,播种时间宜在5~8月。     

不同处理方法对短序润楠种子发芽的影响

采取不同激素处理和不同贮藏方法,对短序润楠种子进行发芽试验,分析其种子发芽率及发芽势。结果表明：不同激素处理后,种子发芽率差异不显著;浓度100mg／LNAA处理后的种子发芽势最高,说明该浓度下的NAA能促进种子的发芽速率。土壤保湿贮藏处理的发芽势和发芽率明显高于其它处理,因此土壤保湿贮藏是提高短序润楠种子萌发能力比较理想的一种方法。     

优良引进饲料灌木树苜蓿种子的6种催芽试验

通过对新引进的优良饲料灌木树苜蓿进行种子催芽、种子生活力鉴定和种子发芽试验,结果表明：6种催芽方法效果差异显著。其中,砂纸磨擦催芽效果最好,其次是变温处理和浓硫酸催芽,碳酸钠和洗衣粉催芽效果居中,沸水处理催芽效果最差,但所有方法的催芽率均不高,种子最高吸胀率只有58．0％。综合考虑其催芽操作难易程度、催芽效果和使用的安全、经济和可行性以及树苜蓿种子含硬实的特性,试验筛选出了碳酸钠和洗衣粉2种比较合适的树苜蓿种子催芽方法。种子生活力鉴定结果表明：种子活力达75％以上,且试验所用催芽药剂及药剂处理浓度和处理时间对种子活力没有太大影响。种子发芽率为94．5％。     

Genetic variability and divergence studies in pod and seed traits of Pongamia pinnata （L.） Pierre., accessions in Bay Islands

In this study, we assessed the variability in pod, seed traits and oil content of 24 accessions of Pongamia pinnata collected from different parts of the Andaman and Nicobar Islands, India. The experiment was conducted at the Central Agricultural Research Institute, Port Blair during 2010 to 2011. The variability studies for pod and seed traits revealed that, the accession CPT-6 collected from New Wandoor in South Andaman recorded the maximum values for eight traits viz. pod length （75.51 mm）, pod width （34.62 mm）, pod thickness （17.55 mm）, 100 pod weight （770.33 g）, seed width （21.23 mm）, 100 seed weight （377.00 g）, oil percentage （43.92%） and germination percentage （94.7%）. However, the maximum seed length （26.46 mm） was recorded from CPT 2 and the maximum pod-seed ratio was obtained from CPT 13 and CPT 4 （2.50 and 2.44 respectively）. The phenotypic and genotypic coefficients of variations were also close to each other for all traits, but the 100 pod and seed weight exhibited higher phenotypic and genotypic coefficient of variation than the other traits. Estimates of broad sense heritability ranged from 0.30 （for seed length） to 0.95 （pod length） and genetic ad- vance as percent of the mean ranged between 11.66% and 57.40% with seed length giving the lowest value and 100 pod weight giving the high- est value. Both the phenotypic and genotypic correlation between pod length, pod width, pod thickness, 100 pod weight, seed width and 100 seed weight and between pod thickness, 100 pod weight, seed width, 100 seed weight and germination percentage were found to be strong. On the basis of non hierarchical Euclidian cluster analysis, 24 accessions were grouped into six clusters. The maximum numbers of seven accessions were included in cluster VI. The maximum intra cluster distance （10.238）shown by cluster VI and the maximum inter cluster distance （17.021） between V and HI followed by III and II （15.942）. Among the six clus- ters formed the cluster III recorded maximum oil percentage, 100 pod weight, 100 seed ,weight, pod length, pod thickness, pod width, seed width and. germination percentage, while cluster V recorded maximum pod seed ratio and germination percentage. The present findings suggest that the crossing between accessions of cluster V and cluster III will result in a wide spectrum of variability in subsequent generations.     

Investigation of salinity impacts on germination and growth of two forest tree species at seedling stage

Soil salinity is becoming an increasingly serious constraint to plant growth in many parts of the world;this is particularly common in semi-arid and arid zones. This study was conducted to evaluate the...     

不同化学药剂和植物激素处理对珍珠绣线菊种子发芽的影响

用高锰酸钾、硼酸、奈乙酸和吲哚乙酸对珍珠绣线菊种子进行浸种处理,研究不同化学药剂和植物激素对其种子发芽的影响。结果表明:高锰酸钾、硼酸、奈乙酸和吲哚乙酸对珍珠绣线菊种子发芽具有明显的促进作用,它们的最适质量浓度分别为2.0mg.L-1、0.2mg.L-1、20.0mg.L-1和10.0mg.L-1,硼酸和吲哚乙酸的处理效果好于高锰酸钾和奈乙酸。