Pub Date : 2010-01-01DOI: 10.1590/S1677-04202010000200004
F. Gondim, E. Gomes-Filho, C. Lacerda, J. T. Prisco, A. D. A. Neto, E. Marques
The aim of this study was to evaluate the effects of H2O2 on germination and acclimation of maize plants subject to salt stress. Three experiments using BRS3003 seeds, a triple hybrid of maize, were carried out in a growth room and in greenhouse. In the first experiment, H2O2 accelerated the germination percentage of seeds at 100 mM, but not at 500 mM. In the second experiment, the pretreatment of seeds was observed to induce a pronounced increase in ascorbate peroxidase (APX) and catalase (CAT) enzyme activity after 30 h of soaking in H2O2. It was also observed that guaiacol peroxidase (GPX) activity was smaller in the seeds soaked in H2O2 for 12, 24, 30, 36 and 42 h, in relation to those soaked in distilled water. The superoxide dismutase (SOD) activity was not affected by the pretreatment of seeds, except for the 24 h treatment. Only one CAT isoform was detected. In the third experiment, seeds were pretreated with 36 h soaking in 100 mM H2O2 solution or in distilled water and later cultivated in Hoagland's nutrient solution or nutrient solution with 80 mM NaCl. The results showed the pretreatment of seeds with H2O2 induced acclimation of the plants to salinity. It decreased the deleterious effects of salt stress on the growth of maize. In addition, the differences in antioxidative enzyme activities may explain the increased tolerance to salt stress of plants originated from H2O2 pretreated seeds.
本研究旨在探讨H2O2对盐胁迫下玉米植株萌发和驯化的影响。以玉米三重杂交种BRS3003种子为材料,在生长室内和温室中进行了3项试验。在第一个实验中,H2O2在100 mM处促进了种子的发芽率,而在500 mM处则没有。在第二个实验中,我们观察到预处理后的种子在H2O2浸泡30 h后,抗坏血酸过氧化物酶(APX)和过氧化氢酶(CAT)酶活性显著增加。H2O2浸泡12、24、30、36和42 h的愈创木酚过氧化物酶(GPX)活性低于蒸馏水浸泡的愈创木酚过氧化物酶(GPX)活性。除处理24 h外,预处理对种子超氧化物歧化酶(SOD)活性无显著影响。仅检测到一种CAT异构体。在第三个实验中,种子在100 mM H2O2溶液或蒸馏水中浸泡36 h,然后在Hoagland’s营养液或80 mM NaCl营养液中培养。结果表明,H2O2预处理种子可诱导植株对盐的适应。降低了盐胁迫对玉米生长的有害影响。此外,抗氧化酶活性的差异可能解释了H2O2预处理种子产生的植物对盐胁迫的耐受性增强。
{"title":"Pretreatment with H2O2 in maize seeds: effects on germination and seedling acclimation to salt stress","authors":"F. Gondim, E. Gomes-Filho, C. Lacerda, J. T. Prisco, A. D. A. Neto, E. Marques","doi":"10.1590/S1677-04202010000200004","DOIUrl":"https://doi.org/10.1590/S1677-04202010000200004","url":null,"abstract":"The aim of this study was to evaluate the effects of H2O2 on germination and acclimation of maize plants subject to salt stress. Three experiments using BRS3003 seeds, a triple hybrid of maize, were carried out in a growth room and in greenhouse. In the first experiment, H2O2 accelerated the germination percentage of seeds at 100 mM, but not at 500 mM. In the second experiment, the pretreatment of seeds was observed to induce a pronounced increase in ascorbate peroxidase (APX) and catalase (CAT) enzyme activity after 30 h of soaking in H2O2. It was also observed that guaiacol peroxidase (GPX) activity was smaller in the seeds soaked in H2O2 for 12, 24, 30, 36 and 42 h, in relation to those soaked in distilled water. The superoxide dismutase (SOD) activity was not affected by the pretreatment of seeds, except for the 24 h treatment. Only one CAT isoform was detected. In the third experiment, seeds were pretreated with 36 h soaking in 100 mM H2O2 solution or in distilled water and later cultivated in Hoagland's nutrient solution or nutrient solution with 80 mM NaCl. The results showed the pretreatment of seeds with H2O2 induced acclimation of the plants to salinity. It decreased the deleterious effects of salt stress on the growth of maize. In addition, the differences in antioxidative enzyme activities may explain the increased tolerance to salt stress of plants originated from H2O2 pretreated seeds.","PeriodicalId":9278,"journal":{"name":"Brazilian Journal of Plant Physiology","volume":"5 1","pages":"103-112"},"PeriodicalIF":0.0,"publicationDate":"2010-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82021098","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2010-01-01DOI: 10.1590/S1677-04202010000100001
J. A. Marchese, J. Ferreira, V. Rehder, O. Rodrigues
Despite the importance of Artemisia annua L. as the only source of the anti-parasitic drug artemisinin, little is known on the effects of biotic and abiotic stress on artemisinin accumulation. Water deficit is the most limiting factor on plant growth, however it can trigger secondary metabolite accumulation, depending on the plant growth stage and intensity. A. annua cultivated in growth chambers was submitted to five water deficit treatments (watered, 14, 38, 62 e 86 hours without irrigation). Water deficits of 38 and 62 hours (Yw = -1.39 and -2.51 MPa, respectively) increased leaf artemisinin content, but only 38 hours led to a significant increase in both leaf and plant artemisinin (29%), with no detriment to plant biomass production. The other treatments had no effect on, or decreased artemisinin accumulation. A. annua plants tolerated well water deficit treatments, including the most severe water deficit applied (Yw -3.97 MPa or 86 hs without irrigation) and recovered their turgor pressure after rehydration. These results suggest that moderate water deficit prior to harvesting the crop may not only reduce time and costs in drying the crop, but can also induce artemisinin accumulation, both of which increase crop profit margins. Results also suggest that artemisinin could be part of A. annua chemical system of defense against water deficit.
{"title":"Water deficit effect on the accumulation of biomass and artemisinin in annual wormwood(Artemisia annua L., Asteraceae)","authors":"J. A. Marchese, J. Ferreira, V. Rehder, O. Rodrigues","doi":"10.1590/S1677-04202010000100001","DOIUrl":"https://doi.org/10.1590/S1677-04202010000100001","url":null,"abstract":"Despite the importance of Artemisia annua L. as the only source of the anti-parasitic drug artemisinin, little is known on the effects of biotic and abiotic stress on artemisinin accumulation. Water deficit is the most limiting factor on plant growth, however it can trigger secondary metabolite accumulation, depending on the plant growth stage and intensity. A. annua cultivated in growth chambers was submitted to five water deficit treatments (watered, 14, 38, 62 e 86 hours without irrigation). Water deficits of 38 and 62 hours (Yw = -1.39 and -2.51 MPa, respectively) increased leaf artemisinin content, but only 38 hours led to a significant increase in both leaf and plant artemisinin (29%), with no detriment to plant biomass production. The other treatments had no effect on, or decreased artemisinin accumulation. A. annua plants tolerated well water deficit treatments, including the most severe water deficit applied (Yw -3.97 MPa or 86 hs without irrigation) and recovered their turgor pressure after rehydration. These results suggest that moderate water deficit prior to harvesting the crop may not only reduce time and costs in drying the crop, but can also induce artemisinin accumulation, both of which increase crop profit margins. Results also suggest that artemisinin could be part of A. annua chemical system of defense against water deficit.","PeriodicalId":9278,"journal":{"name":"Brazilian Journal of Plant Physiology","volume":"11 11 1","pages":"1-9"},"PeriodicalIF":0.0,"publicationDate":"2010-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"79581517","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2010-01-01DOI: 10.1590/S1677-04202010000300004
B. Adamczyk, M. Godlewski
It is now well-known that plants can uptake not only inorganic nitrogen but also organic nitrogen compounds, mainly amino acids. However, soil proteins are the main pool of amino acids. According to our earlier papers, plants can get access to this source of nitrogen using root-secreted proteases, but the level of proteolytic activity of such root-secreted proteases is species-specific. Our aim was to compare the use of protein as nitrogen source by two vegetable crops having high (Allium porrum) or low (Lactuca sativa) level of activity of root-secreted proteases. Seedlings were cultivated on Murashige and Skoog medium (MS), MS medium without inorganic nitrogen, MS medium without inorganic nitrogen, but with casein in concentration of 0.01%, 0.1% or 1%. Fresh weight of shoot of A. porrum was the highest for seedlings growing on culture medium with casein, but shoots of L. sativa obtained the highest weight growing on the culture medium with inorganic nitrogen. Allium porrum seedlings obtained 15-fold higher proteolytic activity in the culture medium than L. sativa. Seedlings of A. porrum using such high activity of proteases secreted by roots could provide a substantial pool of amino acids for intensive growth. The current studies conducted on A. porrum and L. sativa suggest that the efficiency of protein use in nitrogen nutrition by plants is species-specific.
{"title":"Inter-specific variability in protein use by two vegetable crop species","authors":"B. Adamczyk, M. Godlewski","doi":"10.1590/S1677-04202010000300004","DOIUrl":"https://doi.org/10.1590/S1677-04202010000300004","url":null,"abstract":"It is now well-known that plants can uptake not only inorganic nitrogen but also organic nitrogen compounds, mainly amino acids. However, soil proteins are the main pool of amino acids. According to our earlier papers, plants can get access to this source of nitrogen using root-secreted proteases, but the level of proteolytic activity of such root-secreted proteases is species-specific. Our aim was to compare the use of protein as nitrogen source by two vegetable crops having high (Allium porrum) or low (Lactuca sativa) level of activity of root-secreted proteases. Seedlings were cultivated on Murashige and Skoog medium (MS), MS medium without inorganic nitrogen, MS medium without inorganic nitrogen, but with casein in concentration of 0.01%, 0.1% or 1%. Fresh weight of shoot of A. porrum was the highest for seedlings growing on culture medium with casein, but shoots of L. sativa obtained the highest weight growing on the culture medium with inorganic nitrogen. Allium porrum seedlings obtained 15-fold higher proteolytic activity in the culture medium than L. sativa. Seedlings of A. porrum using such high activity of proteases secreted by roots could provide a substantial pool of amino acids for intensive growth. The current studies conducted on A. porrum and L. sativa suggest that the efficiency of protein use in nitrogen nutrition by plants is species-specific.","PeriodicalId":9278,"journal":{"name":"Brazilian Journal of Plant Physiology","volume":"9 1","pages":"171-176"},"PeriodicalIF":0.0,"publicationDate":"2010-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"75143843","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2010-01-01DOI: 10.1590/S1677-04202010000200003
C. Prins, I. Vieira, S. D. P. Freitas
The aroma and fragrance industry is a billion-dollar world market which grows annually. Essential oils comprise the majority of compounds used by these industries. These sets of metabolites are formed mainly by monoterpenes, which are products of the plants' secondary metabolism. Biosynthesized from mevalonate and methylerythitol phosphate, the essential oil production depends not only on genetic factors and the developmental stage of plants, but also on environmental factors which could result in biochemical and physiological alterations in plants modifying the quantity and quality of the essential oil. These modifications impair aromatic plant production aimed at essential oil by reducing their quality. It is desirable to develop techniques of agronomical management to improve essential oil products and their specific compounds. Among other factors influencing essential oil production are plant growth regulators or plant hormones. Endogenous levels as well exogenous application could affect essential oil production and chemical composition. In this review we will present research in which plant growth regulators or their synthetic analogs were used and their effects on essential oil production.
{"title":"Growth regulators and essential oil production","authors":"C. Prins, I. Vieira, S. D. P. Freitas","doi":"10.1590/S1677-04202010000200003","DOIUrl":"https://doi.org/10.1590/S1677-04202010000200003","url":null,"abstract":"The aroma and fragrance industry is a billion-dollar world market which grows annually. Essential oils comprise the majority of compounds used by these industries. These sets of metabolites are formed mainly by monoterpenes, which are products of the plants' secondary metabolism. Biosynthesized from mevalonate and methylerythitol phosphate, the essential oil production depends not only on genetic factors and the developmental stage of plants, but also on environmental factors which could result in biochemical and physiological alterations in plants modifying the quantity and quality of the essential oil. These modifications impair aromatic plant production aimed at essential oil by reducing their quality. It is desirable to develop techniques of agronomical management to improve essential oil products and their specific compounds. Among other factors influencing essential oil production are plant growth regulators or plant hormones. Endogenous levels as well exogenous application could affect essential oil production and chemical composition. In this review we will present research in which plant growth regulators or their synthetic analogs were used and their effects on essential oil production.","PeriodicalId":9278,"journal":{"name":"Brazilian Journal of Plant Physiology","volume":"1 1","pages":"91-102"},"PeriodicalIF":0.0,"publicationDate":"2010-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"75180725","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2010-01-01DOI: 10.1590/S1677-04202010000200005
J. Maia, E. Voigt, C. C. D. Macêdo, S. L. Ferreira-Silva, J. A. Silveira
The salt stress effect in root growth and antioxidative response were investigated in two cowpea cultivars which differ in salt tolerance in terms of plant growth and leaf oxidative response. Four-day-old seedlings (establishment stage) were exposed to 100 mM NaCl for two days. The roots of the two cultivars presented distinct response in terms of salt-induced changes in elongation and dry weight. Root dry weight was only decreased in Perola (sensitive) cultivar while root elongation was mainly hampered in Pitiuba (tolerant). Root relative water content remained unchanged under salinity, but root Na+ content achieved toxic levels as revealed by the K+/Na+ ratio in both cultivars. Then, root growth inhibition might be due to ionic toxicity rather than by salt-induced water deficit. Although electrolyte leakage markedly increased mainly in the Perola genotype, lipid peroxidation decreased similarly in both salt-stressed cultivars. APX and SOD activities were reduced by salinity in both cultivars reaching similar values despite the decrease in Pitiuba had been higher compared to respective controls. CAT decreased significantly in Pitiuba but did not change in Perola, while POX increased in both cultivars. The salt-induced decrease in the CAT activity of Pitiuba root is, at principle, incompatible to allow a more effective oxidative protection. Our results support the idea that the activities of SOD, APX, CAT and POX and lipid peroxidation in cowpea seedling roots were not associated with differential salt tolerance as previously characterized in terms of growth rate and oxidative response in plant leaves.
以两种耐盐性不同的豇豆品种为研究对象,研究了盐胁迫对其根系生长和抗氧化反应的影响。4日龄幼苗(建立期)在100 mM NaCl环境下处理2 d。两个品种的根系在伸长和干重变化方面表现出不同的响应。根干重仅在Perola(敏感)品种中降低,而在Pitiuba(耐)品种中根伸长主要受到阻碍。盐胁迫下,根相对含水量保持不变,但根Na+含量达到毒性水平,K+/Na+比值表明。因此,根生长抑制可能是由于离子毒性,而不是由于盐引起的水分亏缺。虽然电解质泄漏主要在Perola基因型中显著增加,但脂质过氧化在两个盐胁迫品种中都有相似的减少。两种品种的APX和SOD活性均因盐度降低而降低,但其值相近,而臭藻的降低幅度高于对照。Pitiuba品种的CAT显著降低,Perola品种没有变化,而POX在两个品种中均有所增加。原则上,盐对臭根CAT活性的降低与提供更有效的氧化保护是不相容的。我们的研究结果支持了豇豆幼苗根系中SOD、APX、CAT和POX的活性以及脂质过氧化与植物叶片生长速率和氧化反应的差异耐盐性无关的观点。
{"title":"Salt-induced changes in antioxidative enzyme activities in root tissues do not account for the differential salt tolerance of two cowpea cultivars","authors":"J. Maia, E. Voigt, C. C. D. Macêdo, S. L. Ferreira-Silva, J. A. Silveira","doi":"10.1590/S1677-04202010000200005","DOIUrl":"https://doi.org/10.1590/S1677-04202010000200005","url":null,"abstract":"The salt stress effect in root growth and antioxidative response were investigated in two cowpea cultivars which differ in salt tolerance in terms of plant growth and leaf oxidative response. Four-day-old seedlings (establishment stage) were exposed to 100 mM NaCl for two days. The roots of the two cultivars presented distinct response in terms of salt-induced changes in elongation and dry weight. Root dry weight was only decreased in Perola (sensitive) cultivar while root elongation was mainly hampered in Pitiuba (tolerant). Root relative water content remained unchanged under salinity, but root Na+ content achieved toxic levels as revealed by the K+/Na+ ratio in both cultivars. Then, root growth inhibition might be due to ionic toxicity rather than by salt-induced water deficit. Although electrolyte leakage markedly increased mainly in the Perola genotype, lipid peroxidation decreased similarly in both salt-stressed cultivars. APX and SOD activities were reduced by salinity in both cultivars reaching similar values despite the decrease in Pitiuba had been higher compared to respective controls. CAT decreased significantly in Pitiuba but did not change in Perola, while POX increased in both cultivars. The salt-induced decrease in the CAT activity of Pitiuba root is, at principle, incompatible to allow a more effective oxidative protection. Our results support the idea that the activities of SOD, APX, CAT and POX and lipid peroxidation in cowpea seedling roots were not associated with differential salt tolerance as previously characterized in terms of growth rate and oxidative response in plant leaves.","PeriodicalId":9278,"journal":{"name":"Brazilian Journal of Plant Physiology","volume":"1120 1","pages":"113-122"},"PeriodicalIF":0.0,"publicationDate":"2010-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"76789420","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2010-01-01DOI: 10.1590/S1677-04202010000300003
F. F. Cassana, A. R. Falqueto, E. Braga, J. Peters, M. A. Bacarin
Sweet potato (Ipomoea batatas L.) plants were cultivated in vitro in Murashige and Skoog (MS) medium with 20 and 40 g L-1 of sucrose under two different photon flux densities (21 and 60 µmol m-2 s-1). Leaves developed in vitro mostly showed high variable to maximum fluorescence ratio (FV/FM) , indicating good development of photosynthetic apparatus. This ratio decreased during leaf aging, especially in the plants cultivated in vitro on medium with higher sucrose concentration and higher photon flux. Leaves developed ex vitro showed high FV/FM ratio during whole experiment. The effective photochemical efficiency (FV'/FM') was maximum at 15th day after emergence of leaves. Photosynthetic potential rate was higher in leaves developed in vitro than in leaves originated ex vitro.
在含20和40 g L-1蔗糖的Murashige和Skoog (MS)培养基上,在不同光子通量密度(21和60µmol m-2 s-1)下培养甘薯(Ipomoea batata L.)植株。离体发育的叶片大多表现出较高的可变最大荧光比(FV/FM),表明光合机构发育良好。随着叶片老化,特别是在高蔗糖浓度和高光子通量培养基上离体培养的植株,这一比率下降。在整个试验过程中,离体发育的叶片均表现出较高的FV/FM比率。有效光化学效率(FV'/FM')在叶片出芽后第15天达到最大值。离体发育叶片的光合势速率高于离体起源叶片。
{"title":"Chlorophyll a fluorescence of sweet potato plants cultivated in vitro and during ex vitro acclimatization","authors":"F. F. Cassana, A. R. Falqueto, E. Braga, J. Peters, M. A. Bacarin","doi":"10.1590/S1677-04202010000300003","DOIUrl":"https://doi.org/10.1590/S1677-04202010000300003","url":null,"abstract":"Sweet potato (Ipomoea batatas L.) plants were cultivated in vitro in Murashige and Skoog (MS) medium with 20 and 40 g L-1 of sucrose under two different photon flux densities (21 and 60 µmol m-2 s-1). Leaves developed in vitro mostly showed high variable to maximum fluorescence ratio (FV/FM) , indicating good development of photosynthetic apparatus. This ratio decreased during leaf aging, especially in the plants cultivated in vitro on medium with higher sucrose concentration and higher photon flux. Leaves developed ex vitro showed high FV/FM ratio during whole experiment. The effective photochemical efficiency (FV'/FM') was maximum at 15th day after emergence of leaves. Photosynthetic potential rate was higher in leaves developed in vitro than in leaves originated ex vitro.","PeriodicalId":9278,"journal":{"name":"Brazilian Journal of Plant Physiology","volume":"9 1","pages":"167-170"},"PeriodicalIF":0.0,"publicationDate":"2010-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"83466239","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2010-01-01DOI: 10.1590/S1677-04202010000100008
Luciana Maia Nogueira de Oliveira, Alana Cecília Menezes Sobreira, F. Monteiro, D. F. Melo
The present study was undertaken to investigate the changes induced by chilling on fatty acid composition of tonoplast vesicles from hypocotyls of Vigna unguiculata (L.) Walp. The 7 day-old control seedlings were grown at 25°C while treated seedlings were submitted to low temperatures (10°C and 4°C) for 4 days after 3 days germination. The chilling stress resulted in a differential inhibition of plant growth at 10°C and 4°C. Following chilling at 10°C and 4°C, the rate of unsaturated to saturated fatty acids increased under chilling stress. Our results suggest that the increase of unsaturated fatty acids content as well as the higher rate unsaturated/saturate fatty acidsmight be used by V. unguiculata plants as an adaptation mechanism likely to maintain the vacuolar membrane fluidity under low temperatures.
{"title":"Chill-induced changes in fatty acid composition of tonoplast vesicles from hypocotyls of Vigna unguiculata (L.) Walp.","authors":"Luciana Maia Nogueira de Oliveira, Alana Cecília Menezes Sobreira, F. Monteiro, D. F. Melo","doi":"10.1590/S1677-04202010000100008","DOIUrl":"https://doi.org/10.1590/S1677-04202010000100008","url":null,"abstract":"The present study was undertaken to investigate the changes induced by chilling on fatty acid composition of tonoplast vesicles from hypocotyls of Vigna unguiculata (L.) Walp. The 7 day-old control seedlings were grown at 25°C while treated seedlings were submitted to low temperatures (10°C and 4°C) for 4 days after 3 days germination. The chilling stress resulted in a differential inhibition of plant growth at 10°C and 4°C. Following chilling at 10°C and 4°C, the rate of unsaturated to saturated fatty acids increased under chilling stress. Our results suggest that the increase of unsaturated fatty acids content as well as the higher rate unsaturated/saturate fatty acidsmight be used by V. unguiculata plants as an adaptation mechanism likely to maintain the vacuolar membrane fluidity under low temperatures.","PeriodicalId":9278,"journal":{"name":"Brazilian Journal of Plant Physiology","volume":"124 1","pages":"69-72"},"PeriodicalIF":0.0,"publicationDate":"2010-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85711917","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2010-01-01DOI: 10.1590/S1677-04202010000100005
P. Patel, S. Kajal, V. Patel, V. J. Patel, Sunil M. Khristi
Soil salinity is a major limitation to crops production in many areas of the world. The present study reports the impact of salt stress on seeds germination, plant growth parameters and leaf ions accumulation in three cowpea Vigna unguiculata (L.) Walp Indian cultivars: Akshay102, Gomti vu-89 and Pusa Falguni. The electrical conductivity (EC) of the soil was 0.75 dS m−1 and the NaCl treatments increased it to 2, 4, 6, 8 and 10 dS m−1. Germination percentage was recorded 10 days after sowing, while shoot and root dry weights were measured in 45 days old plants. Leaf ion concentrations for Na+, K+, Ca2+, Cl− and proline content were determined. The results showed that the germination percentage of seeds was highly affected by salinity in all cultivars in all salinity levels from 2 to 10 dS m−1. On the other hand, height and weight of all cultivars were less affected by the salt stress. Only at 10 dS m−1 EC, significant reduction in plant height and root length could be found for all three cultivars. Salinity induced a significant increase in Na+, Cl− and proline concentrations, while reduced the accumulation of K+ and Ca2+ in leaves of all the cultivars. Moreover, the tolerance difference between the cultivars was better observed at the lowest levels of salt stress, as reveled in the measurements of K+/Na+ ratio and proline content. In conclusion, this study characterizes Akshay102 as the most tolerant cultivar and establishes the measurements of germination capacity, K+/Na+ ratio and proline accumulation as an important features to be explored in programs for selection and/or development of tolerant cultivars which make possible the utilization of waste saline water as well as the cultivation of vast areas of the tropical world affected by salinity.
{"title":"Impact of saline water stress on nutrient uptake and growth of cowpea","authors":"P. Patel, S. Kajal, V. Patel, V. J. Patel, Sunil M. Khristi","doi":"10.1590/S1677-04202010000100005","DOIUrl":"https://doi.org/10.1590/S1677-04202010000100005","url":null,"abstract":"Soil salinity is a major limitation to crops production in many areas of the world. The present study reports the impact of salt stress on seeds germination, plant growth parameters and leaf ions accumulation in three cowpea Vigna unguiculata (L.) Walp Indian cultivars: Akshay102, Gomti vu-89 and Pusa Falguni. The electrical conductivity (EC) of the soil was 0.75 dS m−1 and the NaCl treatments increased it to 2, 4, 6, 8 and 10 dS m−1. Germination percentage was recorded 10 days after sowing, while shoot and root dry weights were measured in 45 days old plants. Leaf ion concentrations for Na+, K+, Ca2+, Cl− and proline content were determined. The results showed that the germination percentage of seeds was highly affected by salinity in all cultivars in all salinity levels from 2 to 10 dS m−1. On the other hand, height and weight of all cultivars were less affected by the salt stress. Only at 10 dS m−1 EC, significant reduction in plant height and root length could be found for all three cultivars. Salinity induced a significant increase in Na+, Cl− and proline concentrations, while reduced the accumulation of K+ and Ca2+ in leaves of all the cultivars. Moreover, the tolerance difference between the cultivars was better observed at the lowest levels of salt stress, as reveled in the measurements of K+/Na+ ratio and proline content. In conclusion, this study characterizes Akshay102 as the most tolerant cultivar and establishes the measurements of germination capacity, K+/Na+ ratio and proline accumulation as an important features to be explored in programs for selection and/or development of tolerant cultivars which make possible the utilization of waste saline water as well as the cultivation of vast areas of the tropical world affected by salinity.","PeriodicalId":9278,"journal":{"name":"Brazilian Journal of Plant Physiology","volume":"6 3","pages":"43-48"},"PeriodicalIF":0.0,"publicationDate":"2010-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"91455326","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2010-01-01DOI: 10.1590/S1677-04202010000300006
J. P. Graça, F. A. Rodrigues, J. Farias, M. C. Oliveira, C. B. Hoffmann-Campo, S. Zingaretti
To investigate the processes involved in the susceptibility of sugarcane plants to water deficit, several physiological parameters were evaluated in drought tolerant (SP83-2847 and CTC15) and sensitive (SP86-155) cultivars. The water deficit affected the photosynthetic apparatus of all the plants in different ways, within and among cultivars. The photosynthetic rate and stomatal conductance decreased significantly in all cultivars submitted to water deficit. In control plants of the tolerant cultivars (SP83-2847 and CTC15) the photosynthetic rate was higher than in the sensitive cultivar (SP86-155). Cultivar CTC15 showed the highest relative water content during the dry period. The quantum efficiency photosystem II of cultivar SP83-2847 was more stable in the last days of the experimental treatment, suggesting that the decline in relative water content stimulated an adjustment of photosynthetic capacity to tolerate the changes in water availability. As a whole, the tolerant SP83-2847 and CTC15 cultivars exhibited a better photosynthetic performance than the sensitive SP86-155 cultivar. The data suggest that these physiological parameters can be used in the evaluation and distinction of drought tolerant and sensitive sugarcane genotypes.
{"title":"Physiological parameters in sugarcane cultivars submitted to water deficit","authors":"J. P. Graça, F. A. Rodrigues, J. Farias, M. C. Oliveira, C. B. Hoffmann-Campo, S. Zingaretti","doi":"10.1590/S1677-04202010000300006","DOIUrl":"https://doi.org/10.1590/S1677-04202010000300006","url":null,"abstract":"To investigate the processes involved in the susceptibility of sugarcane plants to water deficit, several physiological parameters were evaluated in drought tolerant (SP83-2847 and CTC15) and sensitive (SP86-155) cultivars. The water deficit affected the photosynthetic apparatus of all the plants in different ways, within and among cultivars. The photosynthetic rate and stomatal conductance decreased significantly in all cultivars submitted to water deficit. In control plants of the tolerant cultivars (SP83-2847 and CTC15) the photosynthetic rate was higher than in the sensitive cultivar (SP86-155). Cultivar CTC15 showed the highest relative water content during the dry period. The quantum efficiency photosystem II of cultivar SP83-2847 was more stable in the last days of the experimental treatment, suggesting that the decline in relative water content stimulated an adjustment of photosynthetic capacity to tolerate the changes in water availability. As a whole, the tolerant SP83-2847 and CTC15 cultivars exhibited a better photosynthetic performance than the sensitive SP86-155 cultivar. The data suggest that these physiological parameters can be used in the evaluation and distinction of drought tolerant and sensitive sugarcane genotypes.","PeriodicalId":9278,"journal":{"name":"Brazilian Journal of Plant Physiology","volume":"31 1","pages":"189-197"},"PeriodicalIF":0.0,"publicationDate":"2010-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84769454","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2010-01-01DOI: 10.1590/S1677-04202010000200007
V. Ezin, R. Pena, A. Ahanchede
A greenhouse experiment was conducted to investigate the effect of flooding on two tomato cultivars and two wild related species. Forty days old tomato plants were subjected to a continuous flooding stress of different durations: 0, 2, 4 and 8 days. Plant pots were placed inside larger plastic pots; they were irrigated with excessive quantity of tap water at 25oC so that the level of water above the surface of soil was 15 cm throughout the flooding period. At the bottom of each plastic pot a drilled hole allowed complete drainage of the pot after flooding. Parameters studied include plant height, number of leaves, leaf length, chlorophyll fluorescence, chlorophyll content, wilting, leaf senescence, adventitious root formation, number of flowers and fruits from cluster 2 to 6, average weight per fruit, fruit length and width, total fruit weight from cluster 2 to 6, total yield per plant. LA1579 genotype was more subjected to the deleterious effect of flooding on almost all the parameters studied. Therefore LA1579 genotype is flooding sensitive. Genotypes CLN2498E, and CA4 showed high tolerance to flooding while LA1421 genotype was tolerant to some extent. This experiment provides information that could help in the identification of physiological and agronomical parameters associated with flood-tolerance in vegetables.
{"title":"Flooding tolerance of tomato genotypes during vegetative and reproductive stages","authors":"V. Ezin, R. Pena, A. Ahanchede","doi":"10.1590/S1677-04202010000200007","DOIUrl":"https://doi.org/10.1590/S1677-04202010000200007","url":null,"abstract":"A greenhouse experiment was conducted to investigate the effect of flooding on two tomato cultivars and two wild related species. Forty days old tomato plants were subjected to a continuous flooding stress of different durations: 0, 2, 4 and 8 days. Plant pots were placed inside larger plastic pots; they were irrigated with excessive quantity of tap water at 25oC so that the level of water above the surface of soil was 15 cm throughout the flooding period. At the bottom of each plastic pot a drilled hole allowed complete drainage of the pot after flooding. Parameters studied include plant height, number of leaves, leaf length, chlorophyll fluorescence, chlorophyll content, wilting, leaf senescence, adventitious root formation, number of flowers and fruits from cluster 2 to 6, average weight per fruit, fruit length and width, total fruit weight from cluster 2 to 6, total yield per plant. LA1579 genotype was more subjected to the deleterious effect of flooding on almost all the parameters studied. Therefore LA1579 genotype is flooding sensitive. Genotypes CLN2498E, and CA4 showed high tolerance to flooding while LA1421 genotype was tolerant to some extent. This experiment provides information that could help in the identification of physiological and agronomical parameters associated with flood-tolerance in vegetables.","PeriodicalId":9278,"journal":{"name":"Brazilian Journal of Plant Physiology","volume":"54 1","pages":"131-142"},"PeriodicalIF":0.0,"publicationDate":"2010-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"88101746","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}