光照和盐分对醉马草种子萌发的影响

研究了光照、水分和盐分对醉马草种子萌发的影响.结果表明,醉马草种子萌发对光照不敏感,在黑暗和光照下的发芽率及幼苗长度没有显著性差异.NaCl和等渗透势的PEG对种子的萌发均产生抑制作用,降低了发芽率,且PEG的抑制程度大于等渗NaCl,说明渗透胁迫是影响醉马草种子萌发的主要因素.醉马草种子能在0～398 mmol/L的NaC1浓度下萌发,较低盐浓度有利于根长的生长.     

Seed treatments to overcome salt and drought stress during germination in sunflower (Helianthus annuus L.)

The treated seeds (control, KNO₃ and hydropriming) of sunflower (Helianthus annuus L.) cultivar Sanbro were evaluated at germination and seedling growth for tolerance to salt (NaCl) and drought conditions induced by PEG-6000 at the same water potentials of 0.0, −0.3, −0.6, −0.9 and −1.2 MPa. Electrical conductivity (EC) values of the NaCl solutions were 0.0, 6.5, 12.7, 18.4 and 23.5 dS m⁻¹, respectively. The objective of the study was to determine factors responsible for germination and early seedling growth due to salt toxicity or osmotic effect and to optimize the best priming treatment for these stress conditions.

Results revealed that germination delayed in both solutions, having variable germination with different priming treatments. Germination, root and shoot length were higher but mean germination time and abnormal germination percentage were lower in NaCl than PEG at the same water potential. Seeds were able to germinate at all concentrations of NaCl but no seed germination was observed at −1.2 MPa of PEG treatments. NaCl had less inhibitor effect on seedling growth than the germination. It was concluded that inhibition of germination at the same water potential of NaCl and PEG resulted from osmotic effect rather than salt toxicity. Hydropriming increased germination and seedling growth under salt and drought stresses.     

种子沙引发对转基因抗虫棉耐盐性的影响

 以转基因抗虫棉花品种中棉所41和浙905为材料,以其遗传背景品种中棉所23为对照,研究了种子沙引发处理对转基因抗虫棉品种在0%、1.0%和1.5% NaCl浓度下的萌发率、出土率和幼苗生长特性的影响。结果表明,沙引发处理对转基因抗虫棉品种在盐胁迫下的种子萌发和幼苗生长具有明显的效果,但对于非转基因棉品种的效果不明显。幼苗子叶、茎秆和根的超氧化物歧化酶（SOD）活性、过氧化物酶（POD）活性和丙二醛（MDA）含量测定结果表明,沙引发处理使棉花幼苗的子叶和根部维持了较高的SOD与POD活性,但显著减少幼苗体内MDA的积累,说明沙引发有助于促进棉花在逆境下幼苗生长发育和抗逆性的提高。     

An evaluation of seed and seedling drought tolerance screening tests in wheat

Summary A series of experiments was performed in order to evaluate the significance of seed germination and seedling growth in osmotic media as screening methods for drought tolerance.Ten spring wheat (Triticum aestivum L. em Thell.) and one durum wheat (Triticum durum Desf.) were tested under controlled environments, using polyethylene glycol-6000 (PEG) solutions as the moisture stress inducing media.Tolerance in the rate of endosperm utilization, under stress, prior to the onset of germination varied among cultivars.Germination rate or injury to germination at various concentrations of PEG differed significantly among cultivars. Cultivar rating with respect to injury to germination changed with stress levels. Injury to germination did not correlate with endosperm utilization rate in PEG or in water.Germinating seedlings were tolerant to extreme desiccation up to the stage of emergence of the first leaf from the coleoptile.Growth of photosynthesizing seedlings was monitored as they were carried through an increasing concentration gradient of PEG solutions, ranging from –5.9 to –11.3 bars of water potential. Cultivars significantly differed in seedling growth tolerance to increasing levels of water stress. Seedling growth tolerance across cultivars was not correlated with their germination responses under srress.It is concluded that tolerance to water stress in growing seedlings can be screened for by using PEG-containing nutrient solutions. It can not be predicted from germination tests in osmotica.Work was done under a US-Israel Binational Science Foundation (BSF) Grant no. 1654/78.Contribution from Agricultural Research Organization, The Volcani Center, Bet Dagan, Israel, No. 192-E, 1979 series.     

不同品种小黑麦萌发期耐旱性比较

用不同浓度的聚乙二醇-6000(PEG-6000)溶液处理7个品种的小黑麦种子,测定其发芽率,发芽指数,活力指数、胚根、胚鞘、胚芽长度.结果表明,低浓度PEG-6000对小黑麦种子萌发有促进作用,随着胁迫浓度的增加,对种子萌发的抑制作用明显增强.不同品种表现不同,其中中新830最耐旱,中饲828、中饲237抗旱能力较强,冀饲1号、冀饲2号、NTH 1048、NTH1888耐旱程度中等,劲松49为干旱敏感品种.     

Influence of Soil Temperature on Seedling Emergence and Early Growth of Peanut Cultivars in Field Conditions

Peanut or groundnut (Arachis hypogaea L.) sown in early spring often has poor seed germination and seedling development. The influence of soil temperature on seedling emergence and early growth of six peanut cultivars (Florida MDR98, Southern Runner, Georgia Green, SunOleic 97R, Florunner and C‐99R) was studied in natural field soil profiles in temperature‐gradient greenhouses. We evaluated the influence of a range of soil temperatures by sowing at eight dates between January 2001 and May 2002 in Gainesville, Florida. On each sowing date, two additional temperature treatments (ambient and ambient +4.5 °C air temperature) were evaluated by sowing on either end of each greenhouse and applying differential heating. In total, 16 different soil temperature treatments were evaluated. Each treatment was replicated four times in four different greenhouses. Mean soil temperature from sowing to final emergence in different treatments ranged from 15 to 32 °C. Sowing date, temperature treatment and cultivar had significant effect on seedling emergence and development (V₂ stage). For all cultivars, the lowest germination was observed at the earliest sowing date (coolest soil temperature). Among cultivars, Florida MDR98 was the most sensitive to reduced (cool) temperature with the lowest germination and smallest seedling size at 21 days after sowing, followed by Southern Runner. Georgia Green was the most cold‐tolerant with the highest germination, followed by SunOleic 97R. There were no significant differences among cultivars for base temperature, which averaged 11.7 and 9.8 °C for rate of emergence and rate of development to V₂ stage respectively. These results imply that cultivar choice and/or genetic improvement of peanut for cold tolerance during emergence and seedling development in regions where cooler soil temperatures persist and/or regions where early sowing is desirable.     

种子盐引发对转基因抗虫棉耐盐性的影响

以2个转基因抗虫陆地棉品种为材料,以其遗传背景品种为对照,研究种子引发对转基因抗虫棉在NaCl胁迫条件下的种子萌发和田间出苗的影响。结果表明,0.5%的NaCl处理显著地降低陆地棉种子发芽势和发芽率,其中转基因抗虫棉品种(中棉所41和浙905)的种子萌发和田间出苗率差于遗传背景亲本(中棉所23)。种子盐引发处理可以有效地缓解NaCl的胁迫作用,显著地提高种子的发芽势、发芽率和田间出苗率,显著地提高棉花种子的耐盐性。种子盐引发处理对转基因抗虫棉品种的效果优于非转基因抗虫棉的背景品种。引发剂种类对于其耐盐性的影响有一定的差异,以K2SO4的效果更好,且引发剂的浓度与引发时间之间存在着一定的互作效应,高浓度引发剂的处理时间宜短,而低浓度引发剂的处理时间应适当延长。     

Comparative Effects of Salt and Water Stress on Seed Germination and Early Embryo Growth in Two Cultivars of Sweet Sorghum

In semiarid regions of the Mediterranean basin, water and salinity stresses restrict crop establishment. The effects of salt and water stress on seed germination and early embryo growth (radicle and shoot growth) were investigated in laboratory in two cultivars of sweet sorghum [Sorghum bicolor (L.) Moench] – cv. ‘90‐5‐2′ and cv. ‘Keller’ – to verify how these stresses may limit crop growth during the very early stages of growing season. Six water potentials (ψ) of the imbibition solution (from 0 to ?1.0 MPa) in NaCl or polyethylene glycol (PEG) for salt and water stress tests, respectively, were studied. Daily germination was recorded, and radicle and shoot lengths and dry weights (DWs) were measured 2 days after initial germination. Seed germination was reduced (8–30% lower than control) by water stress at ψ 相似文献   

Varietal Differences of Wheat and Triticale to Water Stress

Six wheat ( Triticurn aestivum L.) and ten triticale (x Triticosecale Wittmack) cultivars were screened for water stress tolerance during germination and seedling stages in the laboratory and growth chamber, respectively. Germinating seeds and hydroponically-grown seedlings were subjected to osmotic stresses of –0.3 and –0.6 MPa using polyethylene glycol M. W. 8000. Both species and cultivar differences were found among the tested genotypes for all the parameters analyzed in both germination and seedling tests. Germination stress index was lower for seed exposed to -0.6 MPa than for -0.3 MPa osmotic stress. A significant relationship was found among plant height, fresh weight and dry weight stress indices evaluated during the seedling test. The cultivars that grew taller under stress conditions had greater dry matter accumulation, as well as higher germination and water uptake stress indices indicating the reliability of height to predict cultivar performance under such conditions. The cultivars Stacy (wheat) and Eu 14/15 (triticale) had higher dry matter accumulation, higher water uptake and leaf water potential, greater height and better germination under stress conditions than the other cultivars tested. Conversely, the cultivars GA 781014 (wheat) and Am 4147 (triticale) performed poorly with respect to all the parameters analyzed. Based on results from germination and seedling tests, the cultivars Stacy and Eu 14/15 were selected for more stress studies in the greenhouse and field.     

Screening for Drought Tolerance: Soybean Germination and its Relationship to Seedling Responses

Seventeen determinate soybean ( Glycine max L.) cultivars from maturity groups V through VIII were screened for drought tolerance during germination and seedling stages. Germinating seeds and hydroponically-grown seedlings were subjected to osmotic stresses of -0.3 and -0.5 MPa using polyethylene glycol M.W. 8000. Genotypic variability was found among the cultivars for all the parameters analyzed in both germination and seedling tests. Germination stress index was lower for seeds exposed to -0.5 MPa than for -0.3 MPa osmotic stress. Lower osmotic potential in the treatment medium was also correlated with lower leaf water potential in seedlings subjected to it. A significant relationship was found between fresh weight and height stress indices. The cultivars that grew taller under drought stress conditions had greater dry matter accumulation and higher germination stress indices indicating the reliability of height to predict cultivar performance under such conditions. The cultivars Lee-74 and Wright had higher dry matter accumulation, greater height, and better germination under stress conditions than the other cultivars tested. Conversely, the cultivars Ra 401 and Bay performed poorly in the drought tests at both levels. In the seedling tests, there was no strong relationship between the leaf water potential and the overall performance of the plant suggesting no clear osmoregulatory mechanism. Based on results from germination and seedling tests, the cultivars Lee-74, Wright , and Ra 401 were selected for further studies in greenhouse and field trials.     

腐胺引发对2个转基因抗虫杂交棉耐盐性的影响

以转基因抗虫杂交种慈抗杂3号和浙杂14为材料,研究了棉花种子不同浓度腐胺引发对于转基因抗虫杂交种在0.5％盐胁迫条件下的发芽、出苗、产量和纤维品质的影响.研究结果,腐胺引发处理可以显著地提高转基因抗虫杂交棉种子在盐胁迫条件下的发芽率、发芽指数和田间出苗率,显著降低平均发芽时间.在含有0.5％盐的沿海滩涂地上,腐胺引发处理后的单株铃数、铃重和衣分无显著差异,但最后的皮棉产量却有显著增加,并可提高纤维的马克隆值和比强度.腐胺处理对非盐胁迫条件下的幼苗体内的SOD活力、POD活力和MDA含量无显著影响,但在盐胁迫条件下可显著或极显著地提高转基因抗虫杂交棉幼苗的体内的SOD与POD活力,显著减少MDA的积累.     

低温、NaCl和PEG胁迫对杉木种子萌发及幼苗生长的影响

为了探讨低温、NaCl和PEG处理对杉木种子萌发和幼苗生长的影响,本研究以杉木第3代种子园收集的种子为供试材料,研究了4℃低温处理,0.025 M~0.3 M的NaCl溶液和5%~30%的PEG溶液对杉木种子发芽率、发芽势、起始萌发时间、萌发时间、幼苗苗高、以及幼苗干重鲜重比的影响。结果表明：低温处理显著降低了杉木种子发芽率和幼苗干重鲜重比,缩短了起始萌发时间和萌发时间,但对种子发芽势和幼苗苗高作用不明显;浓度不小于0.025 M的NaCl和5%的PEG溶液均会显著降低种子发芽率和发芽势,0.2 M的NaCl和20%的 PEG溶液分别是杉木种子萌发极限浓度,即大于此浓度时杉木种子完全不萌发;0.025 M~0.1 M的NaCl和5%~15%的PEG溶液处理均会显著延长种子起始萌发时间,缩短萌发时间,降低幼苗苗高,增加幼苗干重鲜重比。     

盐生植物盐穗木种子和幼苗对干旱胁迫的响应

摘 要：以盐生植物盐穗木的种子和幼苗为材料,研究干旱胁迫下盐穗木种子的萌发特性和幼苗的生理变化,以确定其对干旱胁迫的适应能力。利用PEG人工模拟干旱胁迫,检测盐穗木种子萌发期和幼苗期生长指标和生理指标的变化。结果表明：高渗透势(-0.6~-0.4 MPa)对盐穗木种子萌发有促进作用,提高其初始萌发率,并缩短其达到最终萌发率的时间,且高渗透势处理的最终萌发率与CK无显著差异,而中、低渗透势(-2.0~-0.8 MPa)对盐穗木种子萌发则有抑制作用,降低其初始萌发率,并延长其达到最终萌发率的时间;中、高渗透势(-0.7~-0.3 MPa)刺激了盐穗木幼苗做出积极的生理反应,表现为相对电导率下降、可溶性糖含量增加、过氧化氢酶(CAT)和过氧化物酶(POD)活性增强;综合种子萌发期和幼苗期的表现,盐穗木对在中、轻度干旱环境（渗透势为-0.7~-0.3 MPa）有较好的适应。     

聚乙二醇对谷稗种子萌发及相关生理指标的影响

摘要：【研究目的】研究聚乙二醇（PEG6000）渗透处理谷稗种子对其萌发及相关生理指标的影响,分析谷稗种子萌发和幼苗生长与水分胁迫的关系,旨在研究引发对促进供种萌发和活力的效应,为谷稗的生产管理提供科学依据。【方法】分别以15%、20%、25%、30%浓度的PEG6000对谷稗种子进行24h、60h、100h浸种渗透处理,研究谷稗发芽率、发芽速度、相对电导率、脯氨酸含量的变化。【结果】适宜的PEG6000浓度和浸种时间均能不同程度的促进谷稗种子的萌发,表现为谷稗种子发芽率增高、发芽速度加快、相对电导率下降。当25%PEG6000浸种24h时,脯氨酸含量达633.31ug/mg,是CK的3.56倍,存在极显著差异(P＜0.01)。【结论】PEG6000处理提高了谷稗种子的发芽率、发芽速度和细胞膜系统的完整性,25%PEG6000浸种24h是PEG引发谷稗种子较为适宜条件。     

Smoke-Water and a Smoke-Isolated Butenolide Improve Germination and Seedling Vigour of Eragrostis tef (Zucc.) Trotter under High Temperature and Low Osmotic Potential

The seeds of Eragrostis tef are often exposed to high temperatures and low water availability during unfavourable climatic conditions. This affects germination and seedling stand establishment of the crop. Smoke is currently widely studied for its stimulatory role in seed germination. The effect of smoke-water and a smoke-isolated butenolide was investigated on E. tef seed germination and seedling growth at different temperatures, light conditions and osmotic potentials. Treating E. tef seeds with smoke-water and butenolide increased the percentage germination relative to the control at all tested temperatures. These treatments significantly improved seedling length and the vigour index at 25, 30, 35 and 40 and 30/15 °C. Smoke-water and butenolide increased percentage imbibition from high to low osmotic potential. In comparison with the control, smoke-water- and butenolide-treated seeds of E. tef showed higher percentage germination with decreasing osmotic potential. Smoke-water treatment exhibited significantly longer and more vigorous seedlings than the control between 0 and −0.30 MPa osmotic potential. The findings of this study suggest the possibility of using smoke treatments for minimizing E. tef seedling losses at elevated temperatures and water stress.     

大豆、玉米种子的千粒重与发芽成苗关系的研究

以大豆、玉米种子为试验材料，研究了其不同千粒重对发芽率、出苗率、出苗速度和成苗率的影响。结果表明，千粒重越大，其发芽率、出苗率、成苗率愈高，出苗速度愈快，成苗素质愈好。同时，种子的发芽率与出苗率、发芽率与成苗率以及出苗率与成苗率之间存在极为密切的相关关系。     

PEG胁迫对西伯利亚冰草种子萌发及幼苗生理特性的影响

以PEG-6000模拟干旱胁迫,分析西伯利亚冰草种子发芽率、发芽势、胚根和胚芽长及三叶期幼苗相对电导率、丙二醛和游离脯氨酸含量的动态变化规律.结果表明:1)高渗透势PEG溶液(-0.2,-0.4 MPa)能够促进种子萌发,在-0.4 MPa时,发芽率和发芽势均达到峰值.2)高渗透势PEG溶液(-0.2,-0.4,-0.6 MPa)对胚根伸长具有一定的促进作用,-0.4 MPa最大,但对胚芽表现出一定的抑制作用.3)随着渗透势的降低,发芽率、发芽势、胚根长和胚芽长不断下降,胚根/胚芽的比值持续上升.4)3叶期幼苗相对电导率、丙二醛和脯氨酸含量随胁迫强度的增加,胁迫时间的延长持续增加,相对电导率、丙二醛含量除了-0.4 MPa,1d处理外,其他处理均极显著(p＜0.01)高于对照,脯氨酸含量各处理均极显著(p＜0.01)高于对照,相对电导率、丙二醛和脯氨酸这3个指标均可作为抗旱性评价指标.     

Effect of Sodium Chloride on Germination and Seedling Characters of Different Types of Rice (Oryza sativa L.)

The rice eultivars grown in the tropies and sub-tropics can be broadly categorized as aromatic small grain, local coarse grain and modern high yielding varieties (HYV). The first two categories are traditional rice, and are generally palatable. The aromatic rice has better market value than HYV rice, yet farmers are unwilling to expand its cultivation because of the low yield potential. One possibility to expand the cultivation of traditional rice is o t find stress tolerant cultivars for growing in marginal land. The salinity tolerance of nine rice cultivars representing three from each type of aromatic small grains, local coarse grains and HYV types, was analysed at germination and early seedling stage. Seeds were placed for germination and the seedlings were allowed to grow for nine days at NaCl concentrations of 0, 50, 100, 150 and 200 mM. NaCl decreased the germination index (GI), speed of germination, seedling height and seedling dry matter weight. Seedling characteristics were decreased more than GI. In general aromatic small grain type showed more salt sensitivity than the other two types. Among the nine cultivars Shakkorkhora (aromatic type) showed the least salt tolerance in relation to germination and seedling characters while the other two cultivars of the same group showed tolerance as high as the tolerant cultivars in other types. Generalization of group salt tolerance of rice, therefore, has little value from the agronomic point of view at least at early growth stage. As the number of cultivars employed in this study was only three from each type it is suggested that more cultivars be considered for the purpose of salt tolerant improvement programme of various types of rice.     

不同化学消毒剂对小桐子种子萌发和幼苗生长的影响

用CuSO4、H2O2、NaClO和HgCl2四种化学消毒剂对小桐子种子进行表面消毒,探讨不同消毒剂对小桐子种子萌发和幼苗生长的影响,结果表明:CuSO4消毒不仅效果好,而且还可以提高种子的发芽率、发芽指数和脂肪酶活性。相反,其它消毒剂则不同程度地削弱了种子的发芽率、发芽指数、脂肪酶活性和幼苗的生长。结果表明:CuSO4是一种较好的小桐子种子表面消毒剂。     

Osmotically Primed Seed and Seedling Reactions to Variations in Day/Night Temperature

The effects of alternating day/night temperatures, varying in maxima and minima but all averaging 30 °C, on germination and seedling characteristics of Sorghum bicolor L. (Moench) were investigated. Seeds of sorghum CSV 15 were soaked in 2, 4 or 6 g NaCl l⁻¹ solutions for 2 days at 25 °C, soaked in water for 1 day at 25 °C, or untreated. After treatment, drying and storage, seeds were germinated at 30/30 (day/night), 35/25, 40/20 or 41/19 °C temperature regimes under a polyethylene glycol-induced drought level of −3 bar. Results revealed no advancement of germination percentage but a partial increase in germination speed by osmotic seed treatments. All three osmotic treatments also reduced the plumule/radicle ratio owing to a speculated increase in root over shoot growth. Temperature regimes significantly influenced both germination and seedling characteristics with the optimum temperature appearing to be 35/25 °C. Increasing the temperature amplitude from 30/30 to 35/25 °C increased germination speed, which was reduced by incremental increases in temperature amplitude to 40/20 or 41/19 °C.