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1.
The effects of supraoptimal root-zone temperature (30 °C) on growth and development of roots were investigated in water and soil culture with cuttings of two potato clones DTO-2 (heat tolerant) and LT-1 (heat sensitive) at different plant ages, with different compositions of the nutrient solution, and different light intensities. It is suggested that the negative relation between cutting age and heat susceptibility observed in our experiments, is a reflection of the decreasing shoot/root dry weight ratio rather than of age. Heat damage of root systems increased with the concentration of the nutrient solution, nitrate being the main factor responsible. The influence of light intensity on temperature mediated restriction of root growth was relatively small. However the roots of plants grown under low light intensity (60 W m−2 PAR) appeared to be less stressed by supraoptimal temperature, i.e. roots appeared brighter, thinner and more ramified than plants growing at high light intensity (190 W m−2 ). 相似文献
2.
Osmotically Primed Seed and Seedling Reactions to Variations in Day/Night Temperature 总被引：1，自引：0，他引：1
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. 相似文献
3.
为了解北方白菜型冬油菜膜脂脂肪酸和ATPase活性与抗寒性的关系,以抗寒性强的冬油菜品种陇油7号和抗寒性弱的品种天油2号为材料,研究了不同温度处理(25°C、10°C、2°C、–5°C)后叶片和根系膜脂脂肪酸组分和ATPase酶活性的变化。结果表明,低温胁迫下2个冬油菜品种叶片和根系膜脂脂肪酸组分相同,叶片中不饱和脂肪酸以亚麻酸为主,根系不饱和脂肪酸以亚油酸为主。随处理温度的降低,2个冬油菜品种叶片不饱和脂肪酸含量呈先降低(10°C,2°C)后增加(–5°C)的趋势;陇油7号根中不饱和脂肪酸含量逐步增加,天油2号则逐步降低;在低温条件下(2°C,–5°C),陇油7号膜脂U/S比值、IUFA值高于天油2号;ATPase活性表现为陇油7号逐渐高于天油2号。说明2个冬油菜品种的膜脂在低温响应上存在一定差异,低温下不饱和脂肪酸含量和ATPase活性的提高是强抗寒冬油菜品种在北方旱寒区严酷环境条件下能安全越冬的重要原因。 相似文献
4.
Seed tubers of the variety Ostara were raised in growth chambers of 16°C air temperature continuously. The vessels were placed in a water bath of automatic temperature regulation so that soil temperatures of 16°C and 28°C could be maintained. Four weeks after emergence the plants were treated with 14 CO2 and 24 hours later the plants were harvested. Three more treatments and time harvests followed in two weeks intervals. C-14 activity was determined in soluble carbohydrates, in insoluble carbohydrates, and in non extractable residues respectively of the various plant parts in order to obtain information about the translocation of assimilates in the plant.
While the plants at 28°C soil temperature reduced the soluble sugar levels to 50% up to 70 days after emergence, the plants at 16° brought it down to 33% much faster. — The C-14 activity in insoluble carbohydrates amounted to only 50 % in the plants at 28°C while at 16°C it was more than 2/3 (Tables 1 and 2). — The C-14 activity in non extractable residues is much less at 28°C than at 16°C (Tables 3 and 4). — The starch weight reaches only 30% of the value obtained at lower temperature 70 days after emergence (Table 5). — At the higher temperature starch is also increasingly transferred to the tubers but to a much lesser extent and not from the stems and stolons (Table 6).
Possible causes, particularly the role of phytohormones, and consequences are discussed. 相似文献
While the plants at 28°C soil temperature reduced the soluble sugar levels to 50% up to 70 days after emergence, the plants at 16° brought it down to 33% much faster. — The C-14 activity in insoluble carbohydrates amounted to only 50 % in the plants at 28°C while at 16°C it was more than 2/3 (Tables 1 and 2). — The C-14 activity in non extractable residues is much less at 28°C than at 16°C (Tables 3 and 4). — The starch weight reaches only 30% of the value obtained at lower temperature 70 days after emergence (Table 5). — At the higher temperature starch is also increasingly transferred to the tubers but to a much lesser extent and not from the stems and stolons (Table 6).
Possible causes, particularly the role of phytohormones, and consequences are discussed. 相似文献
5.
Abstract It is a challenge to obtain the appropriate protein concentration in cereals for the intended end‐use. This study examined ambient temperature effects on two spring malting barley cultivars (Henley and Tipple) grown in soil or in solution culture with controlled nitrogen supply in daylight chambers with low temperature (day 18 °C, night 12 °C), and high temperature (23 °C/17 °C) to/after anthesis. In soil‐grown plants, high temperature to anthesis resulted in higher grain nitrogen amount (GNA), grain nitrogen concentration (GNC) and straw nitrogen concentration (SNC). In plants grown in solution, high temperature to anthesis resulted in lower GNA and higher GNC. A temperature rise of 1 °C during the growing period in solution cultivation increased GNC, root nitrogen concentration (RNC) and SNC, by 1.20, 1.35 and 0.33 mg g?1, respectively. In solution culture, GNC was positively correlated with RNC and SNC (P < 0.01). Cv. Henley had higher GNC but lower SNC than cv. Tipple. Cv. Henley was more stable in grain size and cv. Tipple in GNC. The results showed that temperature has a direct effect on GNC. Accounting for temperature fluctuations up to the latest possible nitrogen fertilisation occasion can therefore help when deciding appropriate nitrogen supply for intended end‐use. 相似文献
6.
Temperatures up to 35°C have been shown to increase ethylene production and ripening of propylene-treated kiwifruit (Stavroulakis, G., Sfakiotakis, E.M., 1993. We attempted to study the regulation by high stress temperature of the propylene induced ethylene biosynthesis and ripening in ‘Hayward’ kiwifruit. ‘Hayward’ kiwifruit were treated with 130 μl/l propylene at temperatures from 30 to 45°C up to 120 h. Ethylene biosynthesis pathway and fruit ripening were investigated. Propylene induced normal ripening of kiwifruit at 30–34°C. Fruit failed to ripe normally at 38°C and above 40°C ripening was inhibited. Propylene induced autocatalytic ethylene production after a lag period of 24 h at 30–34°C. Ethylene production was drastically reduced at 38°C and almost nil at 40°C. The 1-aminocyclopropane-1-carboxylic acid (ACC) content was similar at 30–38°C and was very low at 40°C. The 1-aminocyclopropane-1-carboxylate synthase (ACC synthase) and 1-aminocyclopropane-1-carboxylate oxidase (ACC oxidase) activities decreased with a temperature increase above 30°C, but ACC oxidase decreased at a faster rate than ACC synthase. Fruit not treated with propylene showed no ripening response or ethylene production. However, kiwifruit respiration rate increased with temperature up to 45°C, reaching the respiration peak in 10 h. At temperatures up to 38°C, propylene treatment enhanced the respiration rate. After 48 h at 45°C, fruit showed injury symptoms and a larger decrease in CO2. The results suggest that high temperature stress inhibits ripening by inhibiting ethylene production and sensitivity while respiration proceeds until the breakdown of tissues. 相似文献
7.
Twelve European and twelve tropical maize cultivars were grown in polyethylene tubes under three temperature regimes (14/12 °C, 22/20 °C; 30/28 °C). The plants were harvested when the third leaf was fully expanded. The experiments were undertaken in order to: (i) study the general response of root traits of maize seedlings to chilly, temperate and very warm conditions and (ii) find out whether and how the geographical origin of the maize material modifies the results. The results may be summarized as follows: 1. The 22/20 °C temperature regime led to the highest shoot and root dry weight, the greatest total root length, the most apices and the greatest root surface area. However, the optimal temperature for these traits appeared to be either slightly higher or lower than 22/20 °C (optimal temperature for number of apices > shoot dry weight > root surface area > root dry weight). 2. The shoot: root dry weight ratio was almost the same at 14/12 °C and 22/20 °C but increased significantly at 30/28 °C. The root surface area: root dry weight ratio was optimal at 22/20 °C but extremely low at 14/12 °C. The production of apices per unit root dry matter was lowest at 14/12 °C and increased steadily at higher temperatures. 3. The root surface area: shoot dry weight ratio was low both at 14/12 °C and at 30/28 °C. This may indicate that mineral nutrient deficiency, as a result of undersized root systems, is most likely at extremely low and extremely high temperatures. 4. Low temperatures promoted the formation of seminal roots. 5. Temperature affected the dominance of the longest seminal root (= primary root). At 14/12 °C, the primary root was rather short as compared to the seminal roots of higher order. At 30/28 °C, however, the primary root was markedly longer than other seminal roots of higher order. 6. At 14/12 °C, the European cultivars produced more shoot and root dry matter, generated more apices and developed greater root surface area than the tropical cultivars. At 30/28 °C, the situation was reversed. This confirms that the response to different temperatures is modified by the geographical origin of the plant material. 相似文献
8.
不同形态氮素替代部分硝态氮对水培小白菜的生长和品质的影响 总被引：5，自引：2，他引：3
摘 要：为了研究水培生产上营养液中氮素形态对小白菜产量和品质的影响,本实验以华南农业大学叶菜B配方为基础, 研究了水培条件下不同形态氮素（铵态氮、酰胺态氮、氨基酸态氮）替代部分硝态氮对水培小白菜的生长和品质的影响。结果表明,氨基酸态氮和酰胺态氮部分替代硝态氮可以显著促进小白菜的生长,提高小白菜的产量;铵态氮部分替代硝态氮利于小白菜叶绿素和类胡萝卜素含量的增加;氮素为纯硝态氮时,小白菜的根系活力最高,酰胺态氮的替代部分硝态氮后,小白菜根系活力显著下降,但可溶性糖、可溶性蛋白和维生素C的含量显著提高;不同形态的氮素替代部分硝态氮后,降低了小白菜体内硝酸盐的含量,尤以酰胺态氮替代后降幅较大。综合小白菜收获时的产量品质等因素,酰胺态氮替代部分硝态氮对水培小白菜的栽培效果最好。 相似文献
9.
N. Dashti B. Prithiviraj R. K. Hynes D. L. Smith 《Journal of Agronomy and Crop Science》2000,185(1):15-22
Co-inoculation of plant-growth-promoting rhizobacteria (PGPR) with B. japonicum has been shown to increase soybean [ Glycine max (L.) Merr.] nodulation, nitrogen fixation, growth and physiological activity at suboptimal root zone temperatures (RZTs). We studied the survival and growth of seven PGPR inoculated on soybean in a sterile rooting medium at three RZTs (25, 17.5 and 15 °C) on a growth bench. The survival of the two most promising strains ( Serratia liquefaciens 2-68 and S. proteamaculans 1-102) was studied under field conditions in methyl bromide fumigated and non-fumigated soils. In general, population densities varied with temperature. PGPR strains generally colonized the rhizosphere and root surface effeciently at higher RZTs; however, S. proteamaculans 1-102 colonized best at a low RZT (15 °C). The population of PGPR applied to the rhizosphere either with or without addition of B. japonicum increased over time in fumigated soil as compared to non-fumigated soil, indicating that the PGPR survive and proliferate better under fumigated conditions. S. liquefaciens 2-68 had higher population densities both on the root and in the rhizosphere, demonstrating, their ability to colonize under short-season conditions. The possible interactions between the two cultivars (Maple Glen and AC Bravor) and the PGPR were generally not significant, despite observations that growth and yield of AC Bravor respond more strongly to PGPR inoculation. 相似文献
10.
[Objective] This study aimed to explore the effects of spatial soil moisture stress on cotton root growth, and to analyze the corresponding changes in cotton root architecture. [Method] To produce soil moisture spatial stress, cotton spacing was set at 30 cm. The cotton was all irrigated on one side of the pole (the side sampling point). By excavating the cotton root, analysis of the main root bifurcation, which was cultivated away from the irrigation point, could be undertaken. [Result] The analyses of the cotton A (the nearest plant to the irrigation location) root system showed that soil moisture near the irrigation point was distributed uniformly. The root system architecture of the cotton cultivated near the irrigation point mostly presented a symmetrical "umbrella" pattern; the difference in root diameter between the main and lateral roots was 5–6 mm, and the average angle between them was 70°–80°, which decreased with the increase in cotton growth stage. Soil moisture spatial stress influenced the cotton plant C, which was cultivated away from the irrigation point, such that the root system architecture was asymmetrical. The roots of cotton plant C grew towards the high soil moisture zone; 48.15% of the lateral roots became thicker, which acted as a bifurcated main root. The difference in diameter between the bifurcated roots was 1–4 mm, and the average angle of the bifurcated roots along the vertical direction was between 20°–37°, which increased with the increase in cotton growth stage. [Conclusion] The results provide important information on the physiological responses of the cotton root system to the soil moisture environment. 相似文献
11.
为探究水氮耦合对直播早籼稻苗期低温冷害的调控作用,以耐冷品种湘早籼6号和冷敏感品种中嘉早17为供试材料,设置适温不施氮（CK）、低温不施氮（LT-0N）、低温低氮（LT-LN）、低温高氮（LT-HN）、低温淹水不施氮（LTF-0N）、低温淹水低氮（LTF-LN）和低温淹水高氮（LTF-HN）7个处理,处理5d,分析秧苗农艺性状、抗氧化酶活性、渗透调节物质、氮代谢相关酶与光合酶活性、内源激素含量等生理生态特性。结果表明,水氮耦合可缓解低温冷害对直播早籼稻造成的伤害。与LT-LN处理相比,LT-HN处理5d后冷敏感品种中嘉早17的苗高、根数、最大根长、鲜重、干重、顶部第1和第3片叶长显著增加;与LTF-0N处理相比,LTF-LN和LTF-HN处理5d后,不同耐性品种的根数、根长、鲜重和顶部第3片叶长显著增加,LTF-LN处理的根数和鲜重高于LTF-HN处理。与LT-0N处理相比,LT-HN和LTF-LN处理显著增加冷敏感品种中嘉早17叶片氮代谢相关酶和光合酶活性、硝态氮、叶绿素和内源生长促进类激素含量,但降低了叶片抗氧化酶活性、可溶性蛋白、渗透调节物质和内源生长抑制类激素含量,高氮和淹水低... 相似文献
12.
花铃期增温对棉花干物重累积的影响及其生理机制 总被引：3，自引：0，他引：3
以遗传背景相近的棉花(Gossypium hirsutum L.)品种泗棉3号和泗杂3号为材料,于2010年在南京农业大学牌楼试验站(118º50′E, 32º02′N)模拟全球温室化气候,研究花铃期增温对棉花干物质累积的影响及其生理机制。结果显示,增温2~3℃(龄期日均温33.5~35.2℃)的条件下,主茎功能叶SPAD值降低,蒸腾速率(Tr)、气孔导度(Gs)、胞间CO2浓度(Ci)上升,但净光合速率(Pn)下降;棉铃对位叶可溶性蛋白含量大幅上升(Δ%>50%)、可溶性糖及可溶性氨基酸含量小幅下降(P<0.05)、C/N值显著下降(P<0.05);叶片POD、CAT活性大幅下降、MDA含量显著上升;泗杂3号相关指标变化幅度较泗棉3号小。说明尽管2~3℃的增温幅度较小,但在花铃期日均温(33.5~35.2℃)的条件下,植株已处于显著的热胁迫状态,光合产物累积能力受到抑制,棉铃对位叶光合产物输出能力显著下降, 棉株总干物质累积量下降20%左右;增温条件下植株水分吸收能力下降并因此受到一定程度的水分胁迫,但此条件下光合能力下降主要由非气孔因子所致,与叶片膜结构的严重受损关系密切;泗杂3号抗高温能力高于泗棉3号。 相似文献
13.
为探明滴灌条件下基肥减施后移对夏玉米养分吸收和根系生长的影响,在大田条件下,以‘郑单958’为供试材料,研究基肥传统施用(CK)、基肥减施后移至拔节期(T1)及基肥减施后移至大喇叭口期(T2)对夏玉米干物质积累、根系生长、植株氮营养指数、氮素积累、土壤硝态氮含量及产量的影响。结果表明,T1和T2处理拔节期(V6)虽然植株氮营养指数低于1 (0.88),但地上部氮磷钾含量和干物质积累量与CK差异不显著,且T2处理吐丝期(R1)到成熟期(R6)植株氮素积累量高于对照(+33.39%)。处理间收获期夏玉米行间0~20 cm土层硝态氮含量差异显著,其中T2分别低于CK和T1处理41.85%和35.46%,深层80~100 cm土层硝态氮含量T1和T2处理分别低于CK 78.68%和56.02%,差异未达到显著水平。大喇叭口期(V12) 15~30 cm土层根系表面积密度为T2>T1>CK,其中T2和T1分别比CK高25.89%和36.17%,且T2处理30~45 cm土层根系表面积密度也较CK高68.59%。各处理间收获指数及产量差异不显著,但总体T2处理值最高,氮肥利用率比对照也增加12.13%。因此在滴灌水肥一体化条件下,夏玉米生产上应根据地力优化基追比,中高肥力农田玉米基肥可以适当减施后移至拔节期(V6)甚至大喇叭口期(V12),控前促后,降低土壤硝态氮残留,同时促进前期根系下扎。 相似文献
14.
苗期低温胁迫对扬麦16叶片抗氧化酶和渗透调节物质的影响 总被引：12，自引：0，他引：12
以扬麦16为试验材料, 利用人工气候箱模拟低温逆境, 研究-4℃、-6℃和-8℃低温胁迫对小麦苗期生长和叶片生理特性的影响。结果表明, 随着处理温度的降低、胁迫时间的延长, 小麦植株由叶尖萎蔫变黄的2、3级冻害加重至叶片全枯的4级冻害, 甚至大部分茎蘖冻死的5级冻害, –4℃和–6℃处理24 h没有发生4级及以上冻害。–8℃处理24 h和48 h后植株5级冻害比例显著增加, 植株死亡率分别为16.7%和39.6%。低温胁迫初期小麦叶片中SOD、POD和CAT活性均呈上升趋势, 随胁迫程度加重, SOD最先表现出下降趋势, POD和CAT变化稍缓, MDA含量增加。苗期低温胁迫使叶片中游离脯氨酸、可溶性蛋白和可溶性糖含量明显高于对照, 且随温度的降低和处理时间的延长呈上升趋势, 表现出对低温逆境的适应性。 相似文献
15.
M. Sharif Zia M. Salim M. Aslam M. A. Gill Rahmatullah 《Journal of Agronomy and Crop Science》1994,173(1):22-31
The study was designed to investigate the effect of cold irrigation water on rice growth and on uptake of N, P, K and Zn applied ca. 50, 20, 35 and 5 mg kg−1 soil, respectively. Cold temperature of irrigation water reduced rice shoot and root dry weight and plant height, significantly compared to hot temperature treatment. Under low temperature stress N was a major rice growth determinant. Increased shoot concentrations of both P and Zn allevated the low temperature stress. The uptake of N, P, K and Zn reduced significantly at low temperature (16.5–20 °C soil and 20–24 °C flood water) compared to high temperature (24.5–27 °C soil and 26.5–29.0 °C), with the strongest effect being noticed for N, followed by P, K and Zn. Application of N, P, K and Zn increased their uptake in rice shoots. Nitrogen and K had synergistic effect on their uptake. Responses to N and K application and their uptake behavior were well marked at higher than at low temperature whereas reverse was true for P and Zn. 相似文献
16.
贮藏温度对早熟甜瓜采后生理及品质变化的影响 总被引：5，自引：1，他引：4
本文以早熟甜瓜品种‘早黄蜜’为试验材料,贮藏在不同温度（25℃、20℃、15℃、10℃、5℃）条件下,研究贮藏温度对果实生理及品质的影响。结果表明：低温贮藏明显降低甜瓜果实的呼吸速率、乙烯产生速率,同时推迟呼吸、乙烯高峰出现的时间。低温贮藏显著延缓果实硬度的降低,延长贮藏期。贮藏温度在贮藏期内对果实可溶性固形物含量的影响较小。早熟甜瓜贮藏在5℃条件下,贮藏19天出现冷害症状,不能正常后熟。‘早黄蜜’甜瓜在10℃条件下贮藏既能延缓成熟,又能正常后熟。 相似文献
17.
为揭示高抗寒冬小麦品种东农冬麦1号的抗寒分子机制,在北方寒地自然条件下,于越冬前(5℃)和越冬期(-25℃) 分别对分蘖节取样,利用抑制消减杂交技术构建该品种低温胁迫相关基因的cDNA文库。在cDNA文库中随机挑选300个阳性克隆测序,获得230条高质量的表达序列标签(EST)。对该序列进行BLAST比对及功能注释,发现文库中基因组成类型复杂多样,其中应对胁迫的基因(如热激蛋白、CS66、Wcor8等)以及参与编码60S和40S核糖体亚基的基因出现的频率较高,这些基因可能与东农冬麦1号的安全越冬有密切关系。对文库中筛选到的2种未知基因和Clp基因进行荧光定量PCR分析,发现其表达水平随着温度降低而不同程度升高;在弱抗寒性小麦品种济麦22中,这些基因则有不同的表达模式。推测这些基因在抗低温胁迫过程中发挥重要作用。 相似文献
18.
Three experiments were conducted to investigate the effects of high temperatures during seed filling on the alkaloid content of narrow-leaf lupin cultivars. Six cultivars of Lupinus angustifolius were grown in field experiments under different weather conditions in four subsequent years. A high content of alkaloids was found in the seeds harvested in 2006, in which the growing season was characterized by high ambient temperatures during seed filling. A second experiment was performed in the green house at different temperatures (10, 20 and 30 °C) using one cultivar in 2006. This experiment confirmed the results of the field experiments as higher temperatures resulted in a higher alkaloid content of the seeds. In a third temperature stress experiment, three cultivars were grown under long day conditions at day/night temperatures of 30 °C/16 °C and 20 °C/16 °C in growth chambers in comparison with an outdoor control at mean temperatures of 15.5 °C. Like in the other experiments, the seed alkaloid content increased with rising temperature. From these results, it may be concluded that the seed alkaloid content is strongly influenced by the temperature during initiation of flowering up to pod ripening. This has to be taken into account e.g. in trials for cultivar release in which the alkaloid content is a knock-out criterion. 相似文献
19.
《Postharvest Biology and Technology》2007,43(1):158-164
Freshly harvested leeks (Allium ampeloprasum L. var. porrum) were trimmed (leaf tips, roots), had the decayed leaves removed, washed with tap water, cut at 50 cm length and subjected to heat treatment at 55 °C for 0 and 17.5 min. They were then trimmed at the root base and leaves to produce stalks 22 cm in length with or without removal of a 2 cm portion of the base. Minimally processed leeks were tray-packaged, wrapped with 16 μm stretch film and stored at 10 °C for 7 days to determine the effects of base removal and heat treatment on visual (leaf growth, fresh weight loss and discoloration) and nutritional quality after storage. CO2 and ethylene concentrations of packages containing minimally processed leeks showed a wound-induced pattern typical of other fresh cut vegetable tissues. Base removal did not significantly affect respiration but increased ethylene production, while heat treatment increased respiration rate and suppressed ethylene production. Storage of minimally processed leeks at 10 °C for 7 days resulted in a slight decrease of chroma and hue angle of base cross section as well as a decrease of chroma of the upper cross section. Heat treatment prevented the decrease of chroma of the base and upper cross section. Base removal reduced, but did not totally control leaf growth of stored minimally processed leeks. Moreover, it resulted in a decrease of dry matter, soluble solids, total soluble phenols, antioxidant capacity and total thiosulfinates at the end of the storage. A combination of base removal and heat treatment efficiently controlled leaf growth, but these treatments resulted in increased fresh weight and total thiosulfinate loss. 相似文献
20.
H. A. Esechie 《Journal of Agronomy and Crop Science》1994,172(3):194-199
Laboratory studies were conducted to investigate the effect of salinity × temperature interactions on the germination of sorghum. Sorghum bicolor (L.) Moench. Sorghum seeds were sown in petri dishes with saline solutions of varying concentrations (electrical conductivities of 0.01, 6.4, 12.2, 17.4, 22.6, 27.2, 32.1, and 37.2 dSm-1 ) prepared with NaCl. The germination responses of the seeds were determined over a wide range of temperatures (15, 20, 25, 30, 35 and 40 °C) for a period of 8 days. Salinity × temperature interactions were highly significant at each counting date. Although, increased salinity resulted in decreased germination percentages, the detrimental effect of salinity was generally less severe at higher temperatures. Germination rate index, computed from germination counts taken every 2 days, was influenced by salinity and temperature in a similar pattern as final germination. Seed germination was more tolerant to salinity at germination temperatures of 30–40 °C than at 15–25 °C. 相似文献