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1.
Ruxiao Bai Lin Chen Xinjiang Zhang Guohua Wei 《Archives of Agronomy and Soil Science》2017,63(4):513-524
Drip irrigation offers potential for rice (Oryza sativa L.) production in regions where water resources are limited. However, farmers in China’s Xinjiang Province report that drip-irrigated rice seedlings sometimes suffer salt damage. The objective of this study was to learn more about the effects of soil salinity and soil temperature on the growth of drip-irrigated rice seedlings. The study consisted of a two-factor design with two soil salinity treatments (0 and 1.8 g kg?1 NaCl) and three soil temperature treatments (18°C, 28°C and 36°C). The results showed that shoot biomass, root biomass and root vigor were greatest when seedlings were grown with no salt stress (0 g kg?1 NaCl) at 28°C. Moderate salt stress (1.8 g kg?1 NaCl) combined with high temperature (36°C) significantly reduced root and shoot biomass by 39–53%. Moderate salt stress and high temperature also increased root proline concentration by 77%, root malonyldialdehyde concentration by 60% and seedling mortality by 60%. Shoot and root Na+ concentrations, shoot and root Na+ uptake and the Na+ distribution ratio in shoots were all the greatest when moderate salt stress was combined with high temperature. In conclusion, high soil temperature aggravates salt damage to drip-irrigated rice seedlings. Therefore, soil salinity should be considered before adopting drip-irrigation for rice production. 相似文献
2.
为研究不同LED红蓝光质比对水稻幼苗生长和生理特性的影响,以湘早籼45号为试验材料,通过在白光的基础上添加不同光质比例的红光(主波长662 nm)和蓝光(457 nm),设置T1(白光:蓝光=2:1)、T2(白光:蓝光=1:2)、T3(白光:红光=7:1)、T4(白光:红光=2:1)、T5(白光:红光=3:2)、T6(白光:红光=1:2)共6种不同光质配比,以白光为对照(CK),探究不同光质比对水稻幼苗形态指标和生理特性的影响。结果表明,增加红光比例提高了水稻幼苗株高、倒二叶叶长、叶面积、壮苗指数、地下部鲜重、根总长、根总数、根表面积、叶绿素含量和叶片过氧化氢酶(CAT)活性。增加蓝光比例抑制了水稻幼苗的株高、第一叶叶鞘长,但在蓝光作用下水稻幼苗茎基宽、倒二叶叶宽、叶面积、壮苗指数、幼苗生物量、根总长、根总数、根表面积、根体积、叶绿素含量增加。T2的茎基宽和壮苗指数最大,相比CK分别增加了23.1%和51.6%。T3和T4有利于生物量积累以及叶面积和叶片抗氧化酶活性的提高,相比CK,T3和T4叶面积分别提高46.9%和45.6%。综上,LED红光提高了水稻叶片叶面积和抗氧化酶活性,促进幼苗干物质积累和根系系统的发育,蓝光则提高了茎基宽和壮苗指数,对改善水稻幼苗形态和培育壮苗具有重要意义。本研究为优化水稻工厂化育秧光照参数提供了理论依据。 相似文献
3.
Soil or foliar application of nitrogen (N) can increase plant growth and salinity tolerance in cotton, but a combination of both methods is seldom studied under salinity stress. A pot experiment was conducted to study the effects of soil application (S), foliar application (F), and a combination of both (S+F) with labeled nitrogen (15N) on cotton growth, N uptake and translocation under salinity stress (ECe = 12.5 dS m?1). Plant biomass, leaf area, leaf chlorophyll (Chl) content, leaf net photosynthetic (Pn) rate, levels of 15N and [Na+] and K+/ Na+ ratio in plant tissues were determined at 3, 7, 14 and 28 days after N application (DAN). Results showed that soil or foliar nitrogen fertilization improved plant biomass, leaf area per plant and leaf photosynthesis, and a combination of soil- plus foliar-applied N was superior to either S or F alone under salinity stress. Although foliar application favored a rapid accumulation of leaf N and soil application a rapid accumulation of root N, S+F enhanced N accumulation in both leaf and root under salinity stress. The combined N application also maintained significantly greater [K+] and K+/Na+ than either soil or foliar application alone. Therefore, the improved plant growth and salinity tolerance under S+F relative to soil or foliar N application alone was attributed to the increased total uptake of N, balanced N concentrations in different tissues through enhanced uptake and accumulation in both leaves and roots, and higher ratio of K+/Na+. 相似文献
4.
Mukkram Ali Tahir Muhammad Farooq Ghulam Sarwar 《Archives of Agronomy and Soil Science》2013,59(3):247-256
We investigated the effect of exogenously applied silicon (Si) on the growth and physiological attributes of wheat grown under sodium chloride salinity stress in two independent experiments. In the first experiment, two wheat genotypes SARC-3 (salt tolerant) and Auqab 2000 (salt sensitive) were grown in nutrient solution containing 0 and 100 mM sodium chloride supplemented with 2 mM Si or not. Salinity stress substantially reduced shoot and root dry matter in both genotypes; nonetheless, reduction in shoot dry weight was (2.6-fold) lower in SARC-3 than in Auqab 2000 (5-fold). Application of Si increased shoot and root dry weight and plant water contents in both normal and saline conditions. Shoot Na+ and Na+:K+ ratio also decreased with Si application under stress conditions. In the second experiment, both genotypes were grown in normal nutrient solution with and without 2 mM Si. After 12 days, seedlings were transferred to 1-l plastic pots and 150 mM sodium chloride salinity stress was imposed for 10 days to all pots. Shoot growth, chlorophyll content and membrane permeability were improved by Si application. Improved growth of salt-stressed wheat by Si application was mainly attributed to improved plant water contents in shoots, chlorophyll content, decreased Na+ and increased K+ concentrations in shoots as well as maintained membrane permeability. 相似文献
5.
水稻耐低锌基因型的生长发育和若干生理特性研究 总被引：11，自引：1，他引：10
在不同Zn2+活度（pZn2+9.7,pZn2+11.0和pZn2+＞11.5）的溶液培养条件下,研究了水稻耐低锌基因型的生长发育和若干生理特性。结果表明:水稻锌营养存在明显的基因型差异,降低锌离子活度会增加地下部于物质的积累,当Zn2+活度从pZn2+9.7下降到pZn2+11.0时,耐低锌品种的地上部干重虽下降,但因地下部干重显著增加,故总干重相近;锌敏感品种则地上部干重显著下降,而地下部干重增加不明显,总干重显著下降。当严重缺锌（pZn2+＞11.5）时,所有基因型水稻的干重构极显著地下降,但锌敏感品种比耐低锌品种下降得更多。降低Zn2+活度使水稻秧苗的出叶速度减慢,在极度缺锌条件下,敏感品种只能生长到3.5叶,而耐低锌品种能生长到4.5叶左右。对叶绿素和根系氧化力的测定结果表明,轻度缺锌或缺锌初期会使叶绿素含量上升和根系氧化力下降,但严重缺锌时,则使叶绿素含量显著降低,而使根系氧化力明显增加。锌敏感品种比耐缺锌品种的变化更为明显。锌离子活度对秧苗的含水量也有明显的影响。因此,耐低锌基因型在低Zn2+活度条件通过保持较低的根氧化作用,促进根系生长以维持地上部新叶生长,达到低锌适应稳态。 相似文献
6.
La(NO3)3 对盐胁迫下黑麦草幼苗生长及抗逆生理特性的影响 总被引：2，自引：0，他引：2
为探讨稀土元素镧(La)对牧草盐胁迫伤害的缓解作用, 采用水培法研究了叶面喷施20 mg·L-1La(NO3)3 对NaCl 胁迫下黑麦草幼苗生长及其抗逆生理特性的影响。结果表明: 盐胁迫显著抑制黑麦草幼苗的生长, 提高叶片电解质渗漏率及丙二醛(MDA)、O2- 和H2O2 含量, 其作用随盐浓度的增大而增强。超氧化物歧化酶(SOD)、过氧化氢酶(CAT)、抗坏血酸过氧化物酶(APX)活性和抗坏血酸(AsA)、谷胱甘肽(GSH)、可溶性蛋白质、脯氨酸含量随盐浓度增大呈先升后降趋势, 可溶性糖和Na+/K+比逐渐增大, 质膜H+-ATP 酶活性逐渐降低, 过氧化物酶(POD)活性及POD 同功酶数量表达增强。喷施La(NO3)3 处理可降低盐胁迫下黑麦草幼苗叶片的O2- 和H2O2 含量, 提高SOD、CAT、POD、APX 和质膜H+-ATP 酶的活性及POD 同功酶的表达, 使AsA、GSH、可溶性蛋白质、可溶性糖和游离脯氨酸含量及幼苗生物量增加, Na+/K+比降低。表明La(NO3)3 可通过提高抗氧化系统的活性和积累渗透溶质减轻盐胁迫伤害, 从而提高黑麦草的耐盐性。 相似文献
7.
稻麦轮作系统中,麦秸还田腐解产生的有毒有害物质可对下茬水稻幼苗产生不利影响,有效减缓或避免其负面影响对于水稻生产尤为重要,而筛选能够提高水稻秧苗抗性的育秧技术不失为重要途径。通过采用5种不同育秧条件对水稻秧苗进行抗性锻炼,以期提高水稻秧苗对麦秸还田条件的抗逆性和适应性,并在移栽后采取相同的栽培措施(氮素和水肥管理)对其进行评估。试验结果表明,干旱及低营养条件下育秧均降低了水稻株高、生物量以及叶绿素含量,且增加了水稻植株丙二醛含量和脯氨酸含量,使水稻的生长发育受到抑制;而施用秸秆、浇施秸秆腐解液以及酚酸混合液进行育秧的处理均增加了水稻株高、地上部鲜重、叶绿素含量、总根长、根表面积、根体积、根尖数、根分枝数和平均根直径,且均降低了水稻植株丙二醛含量和脯氨酸含量,提高了水稻秧苗对麦秸腐解产生负面影响的抗逆性和适应性。通过在水稻育秧期添加适量麦秸、麦秸腐解液或酚酸混合液均可有效提高水稻秧苗对麦秸还田条件的适应性。 相似文献
8.
《Soil Science and Plant Nutrition》2013,59(6):895-902
Abstract To assess whether grafting raised the salt tolerance of cucumber seedlings by limiting transport of Na+ to the leaf and to test whether the salt tolerance of grafted plants was affected by the shoot genotype, two cucumber cultivars (“Jinchun No. 2”, a relatively salt-sensitive cultivar, and “Zaoduojia”, a relative salt-tolerant cultivar) were grafted onto rootstock pumpkin (Cucurbita moschata Duch. cv. “Chaojiquanwang”, a salt-tolerant cultivar). Ungrafted plants were used as controls. The effects of grafting on plant growth and ion concentrations were investigated under NaCl stress. Reductions in the shoot and root dry weights, leaf area and stem diameter of grafted plants were lower and concentrations of K+ and Cl? in the leaves were higher than those of ungrafted plants under the same NaCl stress. The Na+ concentration and Na+/K+ ratio in scion leaves and in the stems of grafted plants were lower, whereas those in rootstock stems and roots were higher than in ungrafted plants under the same NaCl stress. Shoot and root dry weight, leaf area and stem diameter were negatively correlated with leaf Na+ concentrations and Na+/K+ ratio, but were positively correlated with leaf K+ concentrations. The Na+ concentrations and Na+/K+ ratio were lower, whereas the K+ concentrations in the leaves of grafted “Zaoduojia” plants were higher than those in grafted “Jinchun No. 2” plants under the same NaCl stress. The reductions in leaf area and stem diameter of grafted “Jinchun No. 2” plants were more severe than those of grafted “Zaoduojia” plants. These results indicate that: (1) the higher salt tolerance of grafted cucumber seedlings is associated with lower Na+ concentrations and Na+/K+ ratio and higher K+ concentrations in the leaves, (2) grafting improved the salt tolerance of cucumber seedlings by limiting the transport of Na+ to the leaves, (3) the salt tolerance of grafted cucumber seedlings is related to the shoot genotype. 相似文献
9.
《Soil Science and Plant Nutrition》2013,59(6):691-700
Abstract A hydroponic experiment was conducted to observe the effect of arsenic (As) on a number of physiological and mineralogical properties of rice (Oryza sativa L. cv. Akihikari) seedlings. Seedlings were treated with 0, 6.7, 13.4 and 26.8 µmol L?1 As (0, 0.5, 1.0 and 2.0 mg As L?1) for 14 days in a greenhouse. Shoot dry matter yield decreased by 23, 56 and 64%; however, the values for roots were 15, 35 and 42% for the 6.7, 13.4 and 26.8 µmol L?1 As treatments, respectively. Shoot height decreased by 11, 35 and 43%, while that of the roots decreased by 6, 11 and 33%, respectively. These results indicated that the shoot was more sensitive to As than the root in rice. Leaf number and width of leaf blade also decreased with As toxicity. Arsenic toxicity induced chlorosis symptoms in the youngest leaves of rice seedlings by decreasing chlorophyll content. Concentrations and accumulations of K, Mg, Fe, Mn, Zn and Cu decreased significantly in shoots in the 26.8 µmol L?1 As treatment. However, the concentration of P increased in shoots at 6.7 and 13.4 µmol L?1 As levels, indicating a cooperative rather than antagonistic relationship. Arsenic and Fe concentration increased in roots at higher As treatments. Arsenic translocation (%) decreased in the 13.4 and 26.8 µmol L?1 As treatments compared with the 6.7 µmol L?1 As treatment. Arsenic and Fe were mostly concentrated in the roots of rice seedlings, assuming co-existence of these two elements. Roots contained an almost 8–16-fold higher As concentration than shoots in plants in the As treatments. Considering the concentration of Mn, Zn and Cu, it was suggested that chlorosis resulted from Fe deficiency induced by As and not heavy-metal-induced Fe deficiency. 相似文献
10.
不同基因型水稻苗期氮营养特性差异及综合评价 总被引：7，自引：0，他引：7
氮肥过量施用,不仅造成氮肥大量流失,还增加了农业生产成本,对生态环境带来了巨大的威胁。筛选氮高效基因型水稻品种是提高氮素利用效率、降低环境污染的有效途径。本文利用营养液培养方法,研究了55个水稻品种(系)在相同供氮水平(40 mg·L~(-1))、不同供氮形态(NH_4~+-N和NO_3~–-N)条件下苗期吸收与积累氮素的差异。并采用隶属函数法将评价指标进行标准化,基于氮效率综合值,运用分层聚类热图分析,进行55个水稻品种氮效率类型的划分,为氮高效水稻品种的筛选提供依据。在NH_4~+-N和NO_3~–-N培养下,不同水稻品种的整株生物量、茎叶生物量、根系生物量、根系氮含量、茎叶氮累积量差异性显著,变异系数分别在0.69~0.80和0.57~0.74之间。通过因子分析发现,在NH_4~+-N和NO_3~–-N培养条件下的主成分情况相同,第1主成分由整株生物量、茎叶生物量、根系生物量、整株氮累积量、茎叶氮累积量、根系氮累积量决定,主要为反映植株的生物量及氮素累积量指标;第2主成分由不同器官的氮含量决定。综合水稻苗期氮素吸收累积变异特征及因子分析,将整株生物量、茎叶生物量、根系生物量、茎叶氮累积量作为水稻苗期氮高效综合评价指标。根据隶属函数法计算出的氮效率综合值和采用欧氏距离平方拟合的分层聚类热图,55个供试水稻品种可分为氮高效型、氮中效型、氮低效型3大类,分别占供试品种总数的10.91%、27.27%、61.82%。在NH_4~+-N和NO_3~–-N供应条件下,初步确定‘广两优3905’、‘甬优9号’、‘中籼2503’、‘Ⅱ优602’、‘两优766’和‘深两优1813’为氮高效型品种。 相似文献
11.
Three rice (Oryza sativa L.) varieties viz. ‘CR 683‘, ‘Budumoni’ “Budumoni”, and ‘Akisali’ were grown in sand culture in a greenhouse with three levels of iron (Fe) in nutrient solutions viz., 0.045 (control), 5.34, and 7.12 mM Fe to study the effects of iron on physiology of rice seedling growth. Shoot length, root, and shoot dry weights were reduced significantly by higher levels of Fe in the medium. Results of leaf bronzing have revealed higher bronzing score in the seedlings grown at 7.12 mM Fe in the growth medium. Occurrence of bronzing was severe in varieties ‘CR683’ and ‘Akisali’. Variety ‘Budumoni'maintained higher leaf chlorophyll content, nitrate reductase activity and total soluble protein in the leaves at 5.34 and 7.12 mM Fe. Higher concentration of iron in the nutrient medium exerted an inhibiting effect on the concentration and content of almost all the macro and micronutrients in the root and shoot. Higher Fe and nitrogen (N) contents and lower phosphorus (P), potassium (K), manganese (Mn), copper (Cu), and zinc (Zn) were determined in roots and shoots in plants grown in medium supplied with 7.12 mM Fe. The variety ‘Budumoni’ “Budumoni” performed relatively better in comparison to other tested varieties at 7.12 mM Fe in the growth medium. ‘Budumoni’ “Budumoni” can be considered a suitable rice variety to use in the rice-breeding programme for Fe toxicity tolerance in acid soils of Assam. 相似文献
12.
局部根系盐胁迫对冬小麦生长和光合特征的影响 总被引：3，自引：1，他引：2
通过分根装置设置无盐胁迫(0|0)、局部根系150 mmol-L-1NaCl胁迫(0|150)、全部根系75 mmol-L-1NaCl胁迫(75|75)、全部根系150 mmol-L-1NaCl胁迫(150|150)4种处理,研究根系局部盐胁迫对冬小麦生长及光合特征的影响。结果表明:盐胁迫显著抑制了小麦幼苗的生长,并且随着盐胁迫浓度的增加,小麦受抑制程度加重;根系盐胁迫方式对小麦幼苗生长影响显著,局部根系胁迫处理(0|150)小麦幼苗地上部干重比等浓度150 mmol-L-1NaCl全部盐胁迫处理(150|150)增加23.5%,比等浓度75 mmol-L-1NaCl全部盐胁迫处理(75|75)增加17.2%。在局部根系盐胁迫下,非盐胁迫一侧根系(0|150-0)补偿生长,其根长、侧根数、侧根长比盐胁迫一侧根系(0|150-150)分别增加195.2%、206.2%和237.8%,盐胁迫一侧根系吸收的Na+部分向非盐胁迫一侧根系运输,盐胁迫一侧根系(0|150-150)的Na+含量比全部胁迫处理(150|150)减少12.1%。与全部根系盐胁迫相比,局部根系盐胁迫减少了Na+在叶片中的积累,降低了钠/钾值。局部根系盐胁迫叶片净光合速率、气孔导度、胞间CO2浓度和叶绿素荧光参数(Fv/Fm)均高于同浓度完全盐胁迫处理的小麦幼苗,进而增加地上部和根系的生物量。因此,局部根系胁迫显著缓解了全部盐胁迫对小麦地上部和根系生长的抑制作用。 相似文献
13.
不同微量元素叶面肥对草莓育苗生长的影响 总被引：3，自引：0，他引：3
将硼、钼和铁等微量元素复配成单一或复合叶面微肥,应用于草莓育苗,通过分析草莓生长情况,以确定硼、钼和铁肥的最佳施用量。结果表明:单施硼、钼、铁肥及配施叶面肥均能不同程度促进草莓繁苗数、母株的株高、净光合速率以及母株和子苗的叶面积、SPAD值和地上部和地下部的生物量。其中硼、钼对繁苗数、叶面积的促进效果较为明显,铁对叶绿素和光合作用的促进效果最为明显;总体来看,随着铁浓度的增加,其对母株叶面积、SPAD值、母株地上部和地下部生物量以及子苗的叶面积的促进作用更加明显,但高浓度的硼、钼促进作用则减弱,甚至对繁苗数产生抑制作用;不同微量元素的配施处理中,以硼和钼配施微肥效果最好,显著提高了草莓母株和子苗的地上部和地下部生物量。由此,本试验中0.2%硼肥、0.2%钼肥及各浓度的铁肥以及硼、钼配施为草莓育苗微肥的最佳施用方式。 相似文献
14.
通过水培试验探讨了NO-3胁迫下K+、Ca2+对黄瓜幼苗膜质过氧化及活性氧清除酶系统的影响。结果表明，在相同NO-3浓度胁迫7d后， Ca2+浓度越大，膜脂过氧化产物丙二醛(MDA)含量越高，而K+浓度越大，电解质相对渗透率越高，由此说明K+、Ca2+对细胞膜造成伤害的机理不同。黄瓜幼苗活性氧清除酶系统对K+、Ca2+的响应亦不同，在一定程度上，K+和Ca2+ 可提高SOD、POD和CAT活性，保护植物免受自由基伤害，继而可增强植物对逆境的适应能力。 相似文献
15.
本文利用水培试验和琼脂板培养试验研究了高CO2条件下产量响应存在显著差异的两个水稻品种：II优084(高响应)和武运粳23(低响应),在幼苗期根系形态对高C的响应差异。水培试验结果表明,在幼苗时期,高应答品种II优084在低氮条件下地上部生物量在高CO2下增加28.5%,根系干物质量对高CO2响应显著,增幅为28.5%,而其不定根数目没有显著增加,对干物质量响应贡献较大的为总根长。II优084的总根长在高CO2下增幅为26.3%,不同根粗的根长均有高响应。低应答品种武运粳23低氮下地上部和根系响应不显著,而在正常氮和高氮下则不同。正常氮条件下,地上部对高CO2响应不显著,而根系生物量在高CO2下显著增加76.0%,不定根数目增加25.8%,同时总根长增加45.0%,不同根粗的根长均有高响应,II优084则没有显著响应。在高氮条件下,武运粳23地上部生物量在高CO2下增加35.5%,根系生物量增加80.3%,不定根数目增加38.5%,根系平均直径增加16.7%,总根长无响应,而II优084生物量在高氮下无显著差异。同时,武运粳23在正常氮和高氮下的根系表面积和体积对高CO2响应也较II优084显著。琼脂板培养试验的结果与水培结果一致,武运粳23根系形态对高浓度蔗糖的响应普遍高于II优084。试验结果说明品种对高C环境的响应特征不随培养条件的变化而变化。与植株生长后期不同,在幼苗期正常氮条件下低应答品种武运粳23的根系生物量和各形态指标对高C的响应明显高于II优084,说明水稻苗期生长响应参数与后期产量响应参数不一定一致,可能是由于苗期生长高响应的品种在营养生长期旺长,反而不利于后期生殖生长,从而导致后期产量的低响应。 相似文献
16.
[目的]分析复合缓释保水保肥材料对苗木生长的影响,探索适宜苗木生长的复合材料。[方法](1)选用4个实验组和1个对照组的皂角树进行盆栽试验,对苗木的生长和生理指标进行测量分析。[结果](1)复合缓释保水保肥材料能够显著提高苗木的地径,增加叶片数量和叶面积,增大新梢长度,增加苗木生物量;(2)能够显著提高苗木的叶水势以增强水分利用率,提高苗木对肥料的利用效率,维持苗木的叶片叶绿素含量(SPAD)长期处于较高的数值。[结论]复合缓释保水保肥材料能够显著促进苗木生长。 相似文献
17.
《Communications in Soil Science and Plant Analysis》2012,43(11-12):1913-1927
Abstract Swiss chard (Beta vulgaris cicla ’Fordhook Giant'), bean (Phaseolus vulgaris ’Hawksbury Wonder'), and Agrostis capillaris ’Parys’ were grown in soilless media composed of Pinus radiata bark and 0–41% by volume of dried sewage sludge containing [in mg/kg] cadmium (Cd) [22], copper (Cu) [1,116], and zinc (Zn) [1,121]. Sublots of all mixtures were adjusted to pH 4.5, 5.5, or 6.5. Shoot weights were not reduced by sludge addition but those of Swiss chard and bean shoots declined with pH. Shoot contents of Cu, Cd, and Zn increased with decreasing pH. Shoot Cu concentrations were always sub‐toxic, and in Swiss chard toxicity symptoms were not observed until shoot Zn content reached 1,300 mg/kg. Cadmium in Swiss chard shoots reached 22 mg/kg. Metal concentrations in the shoots were well correlated with total and extractable metals in the media only if pH was included in the regression equations. 相似文献
18.
外源油菜素内酯介导Cu胁迫下番茄生长及Cu、Fe、Zn的吸收与分配 总被引：3，自引：0，他引：3
为了探索外源油菜素内酯对番茄Cu胁迫的缓解效应及机理,采用营养液水培的方法,以‘改良毛粉802F1’番茄为材料,研究外源2,4-表油菜素内酯(2,4-EBR,简称EBR)对Cu胁迫下番茄生长及矿质元素吸收的影响。结果表明:外源EBR能够缓解Cu胁迫对番茄植株的生长抑制。与Cu胁迫处理相比,喷施EBR的番茄叶绿素含量和生物量分别提高39.6%和20.0%,差异均达显著水平;Cu胁迫条件下,外源EBR显著降低番茄根系对Cu的吸收与转运,提高叶片中因Cu过多而降低的Fe、Zn含量,有效调控Cu、Fe、Zn的化学提取态和亚细胞分布水平,降低Cu在细胞内的生物毒性,使之向着有利于番茄生长的方向发展,从而保证Cu胁迫下植株正常的生理生化代谢。Cu胁迫提高了番茄叶片和根系各种化学形态的Cu含量,而外施EBR降低了番茄叶片中除NaCl提取态Cu以外的其他各种形态Cu含量。Cu胁迫下易移动态Cu在叶片中的比例升高,而根系中却下降;外施EBR后,番茄植株中难移动态和易移动态Cu的所占比例接近CK,说明Cu胁迫下EBR对Cu的番茄体内分配具显著调控作用。 相似文献
19.
《Journal of plant nutrition》2013,36(6):1247-1262
Abstract Most investigations on the effect of acid soil on legumes have focused on growth, nodulation, nitrogen fixation, and mineral nutrient uptake. Very little attention has been given to the effects of H+ toxicity per se and calcium (Ca) deficiency per se on germination and seedling survival of legumes, particularly groundnut (Arachis hypogaea L.). This paper reports the effects of solution pH and external Ca on seed germination, seedling survival, and growth of groundnut cv. Falcon in sand culture. The treatments consisted of solution pH values ranging from 3.0 to 6.0 in Experiments 1 and 2, and a factorial combination of pH (3.5, 4.5, and 5.5) and Ca (0, 0.5, 1.0, 1.5, and 2.0 mM) in Experiments 3 and 4. The percentage of groundnut kernels that germinated was little affected by solution pH, and ranged from 86% at pH 3.0 to 92% at pH 6.0. By contrast, seedling survival was more sensitive to pH, with only 51% surviving at pH 3.0 compared with 85% and 92% at pH 5.0 and 6.0, respectively. Increasing the solution Ca concentration diminished the adverse effects of low pH on germination and seedling survival. Total root length increased 425‐fold as the pH was increased from 3.0 to 6.0. Increasing the Ca concentration from 0 to 2.0 mM Ca increased root length by 140% and total root surface area by 95%. Lateral root formation was retarded by the combination of low Ca and low pH. Shoot and root dry mass increased with increasing solution pH and Ca concentration. Results of this study indicate that low pH per se did not impact on germination of groundnut, but significantly reduced seedling survival and early growth. The adverse effects of low pH on seedling growth of groundnut were alleviated by high solution Ca concentrations. 相似文献
20.
Seedlings of two tomato cultivars were exposed to 0, 50, or 100 mM sodium chlroide (NaCl) stress with or without silicon (Si) for 10 days, and leaf electrolyte leakage, root activity, plant growth, and ion sodium, potassium, calcium, and magnesium (Na+, K+, Ca2+, and Mg2+) contents were determined. No significant differences were observed in total biomass and the root/crown ratio of salt-stressed plants treated with exogenous Si, but leaf electrolyte leakage of both cultivars treated with 50 mM NaCl and Si was lower than that in the same salt treatment without Si. Root activities of both cultivars were significantly affected by treatment with NaCl and exogenous Si. Application of Si induced a significant decrease in Na+ content and increases in K+, Ca2+, and Mg2+ contents in leaves of plants treated with 50 mM NaCl, and consequently the K+/Na+ and Ca2+/Na+ ratios increased by at least two times. The effects of Si on the ion contents of the roots were not notable. 相似文献