盐胁迫对葡萄离体新梢叶片的伤害作用

０．４－１．０ＮａＣｌ溶液培养的雷司令葡萄新梢，引起叶片失绿、萎蔫或组织坏死，１．０％ＮａＣｌ导致叶柄蔫坏死。盐胁迫引起叶细胞膜透性增加，叶片产争光合速率和叶圆片暗呼吸明显降低。盐害症状随ＮａＣｌ浓度的增加明显加重，并与叶龄有关。     

苹果砧木组培苗耐盐筛选技术研究

筛选了供试苹果砧木茎尖培养继代苗耐ＮａＣｌ的临界浓度，比较了０．６％ＮａＣｌ对继代苗、生根苗生长的影响。结果表明，继代苗的受害指数、相对增殖系数、相对生物产量、游离脯氨酸含量及细胞膜透性与砧木耐盐性之间存在一定的相关性，以盐胁迫 ５０ ｄ、盐敏感砧木受害指数高于０．７、继代苗生长严重受抑制为标准，确定继代苗耐ＮａＣｌ的临界浓度为０．６％－０．８％；继代苗、生根苗之间存在耐盐相关性。     

苹果砧木组培苗耐盐筛选技术研究

筛选了供试苹果砧木茎尖增减继代苗耐ＮａＣｌ的临界浓度，比较了０．６％ＮａＣｌ对继代苗、生根苗生长的影响。结果表明，继代苗的受害指数、相对增殖系数、相对生物产量、游离脯氨酸含量及细胞膜透性与砧木耐盐性之间存在一定的相关性，以盐胁迫５０ｄ、盐敏感砧木受害指数高于０．７、继代苗生长严重受抑制为标准，确定继代苗耐ＮａＣｌ的临界浓度为０．６％～０．８％；继代苗、生根苗之间存在耐盐相关性。     

五种落叶果树的氯离子分布与耐盐性研究

在盆栽条件下，生长在滨海脱盐土上的猕猴桃出现明显盐害反应；当土壤含盐量（ＮａＣｌ）达０．２％时，毛桃和葡萄植株生长受到明显抑制；达０．３％－０．４％时，银杏和石榴生长控制。银杏、石榴根系木质部氯含量较韧皮部低，而根颈附近地上部木质问 氯含量也比地下部低。桃树正好相反。银杏体内氯含量根比约为２，而葡萄几乎于１，石榴则随土壤盐量增加氯含量根冠比增加。脱落的银杏叶片的氯含量分别为葡萄和桃的３．５－５．６     

NaCl胁迫下石榴和桃植株Na^＋,K^＋含量与耐盐性的研究

石榴和桃是两种耐盐性不同的果树。前者在含盐（ＮａＣｌ，以下同）０．３％土壤上植株Ｎａ＋含量有少量增加，含盐量达０．４％时才大量增加；后者在含盐０．２％的土壤上Ｎａ＋含量增加不多，含盐０．３％土壤上急剧增加。盐处理明显增加植株Ｋ＋含量，Ｋ＋／Ｎａ＋增加。植株Ｋ＋／Ｎａ＋值，石榴平均约为桃的１．５倍，死亡植株Ｋ＋／Ｎａ＋值小于１。ＲＰＸＫＮａ、ＲＳＫＮａ及ＳＸＰＫＭＡ值表明，Ｎａ＋、Ｋ＋经过石榴根系时，Ｎａ＋被韧皮部细胞积累，Ｋ＋优先进入木质部，Ｎａ＋、Ｋ＋从根系向枝条运输时及从枝条木质部向韧皮部转运时，Ｎａ＋被木质部再吸收，Ｋ＋优先向地上部及枝条韧皮部积累。桃对Ｎａ＋、Ｋ＋的选择吸收运输能力较石榴弱。     

柰果半成品保存技术研究

采用正交试验方法研究柰果半成品的保存,探明了柰果的半成品的保存效果与柰果的处理状况,有效ＳＯ２浓度,ＮａＣｌ浓度,苯甲酸钠浓度,ＣａＣｌ２浓度之间的相互关系,结果表明：有效ＳＯ２０．２％￣０．３％,苯甲酸钠０．１％￣０．２％,ＣａＣｌ２ ０．６％￣０．９％保存柰果半成品的效果良好。     

钙和萘乙酸对猕猴桃果实贮藏的影响

室温条件下，１０ｍｇ．ｌ＾－１ＮＡＡ、０．５％ＣａＣｌ２、５％ＣａＣｌ２和５％ＣａＣｌ２与１０ｍｇ．ｌ＾－１ＮＡＡ混合使用均缩短猕猴桃果实贮藏期，而０．５％ＣａＣｌ２与１０ｍｇ．ｌ＾－１ＮＡＡ混合处理能延长果实贮藏期。     

钙和萘乙酸对猕猴桃果实贮藏的影响

室温条件下，１０ｍｇ·ｌ~(-１)ＮＡＡ、０．５％ＣａＣｌ_２、５％ＣａＣｌ_２和５％ＣａＣｌ_２与１０ｍｇ·ｌ~(-１)ＮＡＡ混合使用均缩短猕猴桃果实贮藏期，而０．５％ＣａＣｌ_２与１０ｍｇ·ｌ~(-１)ＮＡＡ混合处理能延长果实贮藏期。     

洋葱在产籽时期的耐盐性

在用ＮａＣｌ、Ｎａ２Ｓｏ４、ＮｇＭ１２和ＭｇＳＯ４人工盐化了的花盆里研究了洋葱产籽时期的耐盐性。当土壤含盐量值分别超过４．０ｄＳｍ－１和６．０ｄＳｍ－１时，洋葱鳞茎的发芽率和营养生长下降。土壤含盐量（ＥＣｅ）每提高１单位（ｄＳｍ－１），洋葱种子产量则以６％的速率降低。在含盐量为８．１０ｄＳｍ－１时，洋葱种子产量与一个未盐化的对照比减少５０％。在盐渍状态下，种子千粒重仍不受影响。含盐量对种子发芽无不良作用。     

酸枣叶片不定植株的诱导

从酸枣实生苗叶片获得再生不定植株，在ＷＰＭ附加ＴＤＺ２．０ｍｇ．ｌ＾－１和ＩＡＡ０．５ｍｇ．ｌ＾－１的培养基上获得了４７．６％的不定梢再生率。不定梢转移到培养基ＭＳ＋ＢＡ０．５ｍｇ．ｌ＾－１上增殖，在１／２ＭＳ＋ＩＢＡ０．３ｍｇ．ｌ＾－１＋蔗糖２％培养基上诱导生根，仅获得１３．１％的生根经。     

矮牵牛耐盐生理特性研究

通过对矮牵牛进行盐胁迫处理,研究其耐盐的主要生理特性。结果表明:矮牵牛细胞膜透性受盐胁迫影响,并且与植株含水量负相关。在氯化钠浓度为0.4%时,细胞膜透性最低,植株含水量最高。矮牵牛脯氨酸积累、SOD活性增强均与盐胁迫程度正相关。脯氨酸可参与细胞渗透调节,SOD可清除活性氧伤害,都会对细胞膜产生有效保护作用,可能是细胞膜透性降低的重要原因。矮牵牛对0.4%的盐度具有耐受性。     

Effects of salinity on nitrate,total nitrogen,soluble protein and free amino add levels in tomato plants

The effects of salinity on nitrogen compounds were studied in three tomato (L. esc- ulentum Mill.) genotypes of different salt tolerance. The plants were grown under controlled conditions, and the salt treatments (0, 70 and 140 raM NaCl) were applied for three (Harvest 1) and ten (Harvest 2) weeks. The effects of salinity on total N and particularly N03 concentrations depended partly on the NaCl level and duration of the stress, but mainly on the different degrees of salt tolerance of the genotypes. In Harvest 1, the most tolerant genotype (GC-72) showed the highest N03 increase in the roots and no decreases in stem and leaf with increasing salinity; the intermediate-tolerant genotype (P-73) showed a similar response to that of GC-72 only at 70 mM NaCl. However, the most sensitive genotype (Volgogradskij) showed the greatest reductions in stem and leaf N03 concentrations with salinity. With longer durations of stress the different responses between the more tolerant genotypes were less evident; only Volgogradskij continued to show the highest decreases in stem and leaf N03 concentrations. A restriction of N03 transport from the root to the shoot was noted in the plants of the more tolerant genotypes treated for three weeks. This capacity for retention disappeared when the salinity induced reductions in the total N03 contents in the plants, as in the harvest 2. There was an inverse relation between N03 and Cl accumulations in shoots of all genotypes and its slope decreased with the salt sensitivity of the genotype. There was no relation between the leaf protein content and the salt tolerance of the tomato genotypes. In Harvest 1, a higher accumulation of amino acids, especially proline, was found in the leaves of the more tolerant genotypes at 140 mM NaCl. However, in Harvest 2, a similar accumulation of leaf proline was found in all genotypes, independent of their salt tolerances, and the other amino acid contents remained similar or else decreased with salinity.     

盐胁迫对滨梅幼苗生长和渗透调节物质含量的影响

以滨梅幼苗为试材,研究了不同浓度盐(NaCl)胁迫下植株生长及渗透调节物质的响应。结果表明:0.5%NaCl能显著促进滨梅幼苗的生长及水分代谢,但相对膜透性与对照比无显著差异;1.0%NaCl与对照无显著差异,2.0%NaCl显著抑制滨梅幼苗生长及水分代谢,相对膜透性显著增加;随着NaCl浓度的增加,滨梅叶内的可溶性蛋白、可溶性糖含量及有机渗透调节物质总量显著增加,而脯氨酸含量的变化不明显。     

不同形态氮素对盐胁迫下番茄细胞超微结构与光合作用的影响

研究了在150 mmol ? L-1 NaCl胁迫下含铵态氮、硝态氮和硝酸铵（氮素浓度均为3 mmol ? L-1）的营养液培养的番茄幼苗生长、细胞超微结构、根系活力和光合作用参数的变化。结果表明：NaCl胁迫下,硝态氮处理叶片细胞出现伤害现象,而硝酸铵处理未见明显变化。铵态氮处理细胞超微结构明显发生破坏性变化,盐胁迫下,其伤害加剧。NaCl处理下,不同氮素形态处理下的植株生物量和根系活力均显著下降,其中硝酸铵处理的植株生物量和根系活力维持最高。NaCl胁迫下3种氮素形态处理的植株净光合速率（Pn）和蒸腾速率（Tr）均显著下降,其中硝酸铵处理的Pn和Tr要明显高于其他氮素处理。NaCl胁迫下,硝态氮处理和硝酸铵处理的水分利用效率（WUE）和气孔限制值（Ls）均明显上升,而铵态氮处理显著降低。综上,盐胁迫下,硝酸铵处理下番茄幼苗可维持较好的细胞超微结构、根系活力和较高的光合作用,维持较高的生物量,从而维持较高的耐盐性。     

盐胁迫对黍子种子萌发的影响

选取浓度为0.4%、0.8%、1.2%、1.6%、2.0%、2.4%的NaCl、MgCl2和Na2SO4对黍子种子进行发芽试验。结果表明:黍子种子在不同种类的盐胁迫下发芽率、发芽势、发芽指数、发芽值均低于对照组,且随着盐浓度的升高而降低。在NaCl、Na2SO4及MgCl2胁迫下,黍子种子萌发可忍耐的浓度范围分别为0%~1.2%、0%~1.6%、0%~2.0%。3种单盐胁迫条件下对黍子种子萌发的抑制作用依次为NaClNa2SO4MgCl2。     

Proline and light as quality enhancers of rocket (Eruca sativa Miller) grown under saline conditions

Stress conditions experienced during growth may affect plant responses during post-harvest storage and eventually determine the overall quality of commercial products. In this context, we hypothesized that foliar applications of proline during the growth cycle and light exposure during post-harvest storage could be two important modulators of yield and quality parameters of rocket plants exposed to NaCl stress. Dry matter percentage increased upon NaCl treatment. However, fresh weight loss during storage did not change over time as a consequence of salt stress. High salinity (100 mM NaCl) moderately reduced both leaf nitrate (14%) and nitrite (3%) contents. Lipophilic (LAC) and hydrophilic (HAC) antioxidant activities also decreased by 10% at the highest salinization (average of two growth cycles). In contrast, during storage, LAC decreased whereas HAC increased. Proline applications reduced the leaf nitrate content during storage by 16%, increased carotenoids and chlorophyll contents in salinized plants and also increased the ascorbate leaf concentration in both salinized and non-salinzed plants. Light storage enhanced fresh weight loss in contrast to dark storage. However the exposure to light reduced leaf nitrate levels by 7% (average of two growth cycles) and contributed to maintain high leaf ascorbate concentrations over time.     

盐胁迫对甜菜叶、根主要生理指标的影响

研究了营养液中不同盐度（0.2%～0.8%）对甜菜代号＂K＂叶片和根主要生理指标的影响。结果表明：随着NaCl浓度的增加,甜菜幼苗叶片的单株叶面积、相对含水量、肉质化呈先升高后降低的趋势;游离脯氨酸和可溶性糖含量在叶片中呈逐步升高趋势;在根内则呈下降趋势。研究证实了NaCl浓度低于0.4%,对甜菜的生长发育有明显促进作用;超过0.6%的高浓度NaCl对甜菜的生长有胁迫作用,浓度越高胁迫作用越强。     

盐胁迫对凤仙花种子萌发的影响

采用浓度为0%、0.2%、0.4%、0.6%、0.8%、1.0%的NaCl、Na2CO3、NaHCO3单盐胁迫凤仙花种子,通过对种子萌发特性的观察,研究不同盐分对其危害程度。结果表明:3种盐胁迫对凤仙花种子的萌发时滞、发芽率、发芽势、生长速度的影响差异明显。相同浓度下,Na2CO3胁迫时发芽率和生长速度受到显著抑制,NaCl胁迫时,发芽和生长受到的影响较小;NaHCO3胁迫时受到的抑制介于中间。综合分析,3种盐对凤仙花种子萌发影响的强弱顺序为:Na2CO3NaHCO3NaCl。     

外源Ca~(2+)对莲藕幼苗盐胁迫的缓解效应

以莲藕H_2(花藕品种,盐敏感)为材料,利用NaCl与Ca(NO_3)_2处理3片立叶的幼苗,研究外源Ca~(2+)对缓解植株盐胁迫的生理作用。结果显示:采用NaCl处理后,叶片中叶绿素、可溶性蛋白含量和SOD活性显著降低,而细胞膜透性、丙二醛和脯氨酸含量升高;利用不同浓度的Ca~(2+)进行缓解处理,发现外源施加低浓度的Ca~(2+)后,叶片叶绿素、可溶性蛋白含量和SOD活性均显著提高,脯氨酸含量较之前升高幅度更大,而细胞膜透性和丙二醛含量后期显著降低,说明Ca~(2+)对缓解莲藕盐胁迫具有较好的效果。当Ca~(2+)浓度增加时,缓解作用不明显,甚至出现抑制效果。     

Changes in chlorophyll,ribulose bisphosphate carboxylase-oxygenase,glycine betaine content,photosynthesis and transpiration in Amaranthus tricolor leaves during salt stress

Summary

We examined changes in leaf growth and chemical composition, including chlorophyll content, ribulose bisphosphate carboxylase-oxygenase (RuBisCO), and glycine betaine (GB) in relation to photosynthesis and transpiration responses to salt stress in Amaranthus tricolor leaves. To induce salt stress, plants were transferred to a growth medium containing 300 mM NaCl for 7 d followed by 7 d of relief from salinity. A decrease in leaf enlargement began 3 d after salt stress, and leaves subsequently showed the same degree of regrowth as controls after relief in non-salt medium. Chlorophyll content expressed on a leaf-area basis increased under conditions of salinity due to a reduction in leaf tissue water content. The decrease in chlorophyll content continued throughout the 7 d of relief from salinity. The RuBisCO and soluble protein contents when expressed on a leaf dry-weight basis decreased in response to salinity, and then gradually increased during the relief period. GB content increased slightly up to 3 d of salt stress, and showed typical accumulation during salt stress. GB content decreased sharply immediately after plants were transferred to non-stress medium, but remained at a higher level throughout the relief period. A decrease in photosynthetic activity and transpiration rate preceded any changes in leaf area, RuBisCO or GB content. During relief from salinity, photosynthesis and transpiration rates gradually recovered to control levels with restoration of stomatal conductance. The above findings suggest that the increase in GB content is important in adaptation to salt stress in Amaranthus plants, although photosynthesis and transpiration responses occurred immediately after salt-stress.