盐胁迫条件下不同栽培措施对棉花生长的调控作用研究

研究了盐胁迫对棉花生长的影响以及不同栽培措施对盐胁迫下棉花幼苗生长和产量形成的调控作用。结果表明,在含盐量为 3.0 g/kg 的土壤上,棉花生长受到明显抑制,幼苗功能叶叶面积和生长速率明显下降,果枝数和棉铃数减少,产量和生物量降低;施用有机肥处理能改善盐胁迫下棉花幼苗生长,促进棉苗果枝和棉铃的形成,提高棉花产量和生物量。     

不同耐盐性作物对盐胁迫的响应研究

通过盆栽试验,研究了对盐胁迫具不同抗性水平反应的作物大麦和菠菜,在不同盐分离子种类Na2CO3和NaCl3、个盐分水平(2.0,3.5,5.0g kg-1)条件下的生长、生理指标变化,揭示其对盐胁迫的不同适应机理。结果表明,随土壤盐浓度的升高,大麦的株高、有效分蘖数、产量和生物量均有所下降,菠菜生长受到的抑制状况更加明显。随土壤盐浓度的升高,大麦叶片丙二醛(MDA)的含量逐渐增加,Na2CO3处理的叶片中MDA含量最高。与大麦相比,菠菜在盐胁迫下,更多的Na 通过根部向地上部运输,使叶中积累了更多的Na 。大麦有较强的阻止盐分离子向叶片运输、维持叶片正常功能的能力。Na2CO3更易对植株叶片产生伤害。     

盐胁迫下不同小麦品种的耐盐性及其离子特征

用盆栽试验方法研究了盐胁迫环境中三种小麦品种的生长速率与耐盐笥差异。结果表明,盐度处理对小麦品种“德系ｊ８６－３３－２５”和“鲁麦１０号”植株生长速率的影响低于对“科２６”品种的影响,前两个品种较“科２６”品种更为耐盐。     

转玉米ZmMPK7基因烟草响应高盐胁迫的光合特性和抗氧化酶系统分析

以烟草NC89品种野生株系(WT)和转玉米ZmMPK7基因株系为材料,在NaCl胁迫条件下,对其光合特性和抗氧化酶活性进行分析,以探讨转ZmMPK7基因烟草的耐盐性。结果表明,随盐胁迫加重,转基因烟草植株比野生型具有更高的净光合速率(Pn)、PSⅡ最大光化学效率（Fv/Fm）和叶绿素含量（Chl）,并且转ZmMPK7基因株系能提高烟草叶片抗氧化酶活性,诱导抗氧化酶 (SOD、APX、CAT和POD)活性之间协调变化。与野生型相比,转基因烟草植株MDA含量及电解质外渗量较低,膜脂过氧化较轻,其耐盐性得到改善。     

EFFECTS OF PHYTOHORMONES ON PROLINE CONTENT AND ANTIOXIDANT ENZYMES OF VARIOUS WHEAT CULTIVARS UNDER SALINITY STRESS

Salinity stress is one of the important agricultural problems in the world. A factorial experiment based on completely randomized design with four replications was conducted to evaluate the effects of phytohormones (gibberellic acid and abscisic acid) on the activity of antioxidant enzymes (peroxidase, superoxide dismutase and catalase), rubisco activity and content, and proline in three wheat cultivars (Gascogen, Zagros, and Kuhdasht) under control and salinity stress (3.5 and 7 dS m^?1). The results showed that salinity stress (3.5 and 7 dS m^?1) decreased the activity of catalase, rubisco, carboxylase, but increased peroxidase, superoxide dismutase activity and proline content. Gibberellic acid caused 58.03% increased in rubisco carboxylase activity in Zagros at 7 dS m^?1 in comparison with abscisic acid under salinity stress compared with the control plants in Kuhdasht. Activity of superoxide dismutase in Kuhdasht cultivar at 7 dS m^?1 salinity level showed 76.43% increased in Gascogen under salinity stress compared with the control plants with gibberellic acid application. The highest proline content as an osmolyte was found in Zagros at 7 dS m^?1 salinity level with abscisic acid (194 μmol g^?1 DM) application. Peroxidase activity increased 83.31% and catalase activity decreased 61.27% compared with the control plants in Zagros. Gibberellic acid application significantly prevented reduction in rubisco content under salinity stress. In conclusion, increased in peroxidase and superoxide dismutase activity and proline content decreased the adverse effects of salinity stress on studied cultivars. Also, the foliage spray of gibberellic acid enhanced and improved the growth condition. In this experiment, Zagros cultivar showed more tolerance to salinity stress than the other two cultivars.     

渗透胁迫下硼对细胞膜的保护作用

选用秦油2号油菜为供试材料，研究不同硼（B）浓度对植株的生长状况及细胞膜功能的影响。测定结果表明:油菜生长的最适硼浓度为0.5mg／L，B浓度过高或过低对植株抑制严重;在不同水势条件下处理，适宜的B浓度可以降低渗透胁迫对质膜的伤害，提高作物抗旱性。     

渗透胁迫下的蓝藻固氮作用

渗透胁迫下,蓝菏的固氮活性下降,去铵阻抑速率减小,下降程度随渗透胁迫的增高而增大,光合使用受抑Ｏ２和Ｎ２分压增高均加剧渗透胁迫对固氮酶活性的抑制。添加外源蒸糖,供应ＣＯ２,同时供应ＣＯ２和Ｎ２或Ｈ２和Ｏ２时,渗透胁迫对固氮酶活性的抑制程度明显减弱。     

EXOGENOUS APPLICATION OF POTASSIUM NITRATE TO ALLEVIATE SALT STRESS IN RICE SEEDLINGS

□ Overall growth characteristics of many plant species cultivated in soil affected by salinity could be alleviated by the application of potassium nitrate (KNO₃) to the soil. The aim of this research was to investigate salt-tolerance in a salt-sensitive rice cultivar, ‘Pathumthani 1’ (PT1), in response to the exogenous application of 11.8 mM KNO₃, in comparison to ‘Homjan’ (HJ), a salt tolerant cultivar. Water potential (ψ_w) in both the roots and leaves of PT1 seedlings under salt stress dropped significantly, while it was maintained in PT1 pretreated with KNO₃, and similarly in HJ. The reduction of leaf water potential was positively related to total chlorophyll degradation, leading to diminished chlorophyll fluorescence, directly affecting growth in plants exposed to salt stress. In salt-sensitive PT1, the application of 11.8 mM KNO₃ improved salt-tolerance via the conservation of water use efficiency, the maintenance of photosynthetic pigments, enhancement of chlorophyll a fluorescence, and stimulation of growth characters.     

盐胁迫下AM菌侵染的棉花幼苗根系蛋白质组分析

研究了盐胁迫对棉花幼苗生长的抑制作用和AM真菌侵染根系对盐胁迫的缓解作用。分别以水(对照),0.5% NaCl(盐胁迫组)和AM组(盐胁迫组中加入AM接种剂,浓度为12g/L)培养棉花幼苗30d,取根部进行外观比较,并提取各组根系中的蛋白质,利用双向电泳技术分析棉花幼苗根系蛋白质组的变化。结果表明,盐胁迫组的幼苗根系主根稍细,侧根很少,而对照和AM组主根饱满且侧根丰富,说明AM真菌能抑制盐对幼苗根部的胁迫作用。通过扫描分析3组胶图,发现有4个蛋白质斑点表现出显著的变化,盐胁迫组中均表现为表达量下降,在AM真菌与盐共处理时,这4个蛋白质点的表达均有不同程度的恢复;经鉴定分析,其中2个蛋白质斑点(S1,S2)分别被鉴定为葡萄糖磷酸变位酶与异黄酮还原酶类;同时在AM组还出现3种对照中没有的蛋白质(S5、S6、S7),可能与AM提高作物耐盐性途径相关。     

盐胁迫下转Bt基因棉的K+、Na+转运及SOD活性的变化

通过对转Bt基因棉(苏抗103)和受体棉(苏棉12)在不同浓度盐胁迫条件下的钾钠离子的转运、累积分布以及它们SOD活性和H2O2含量变化的比较,证明了Bt抗虫基因的导入一方面导致棉花植株地上部钾累积增多,根部钾含量降低,从根往地上部的钾转运能力增强,而且根吸收能力也有增强趋势;然而另一方面,受盐胁迫时转Bt基因棉对钾的向上运输选择性减弱,地上部钠积累偏多,盐耐性减弱;SOD活性受盐胁迫影响,下降显著,超氧自由基的清除能力可能受到影响。结果表明,与常规棉有所不同,转Bt基因棉可能不太适宜在盐碱土壤上种植。     

MYCORRHIZAL INFLUENCE ON FRUIT YIELD AND MINERAL CONTENT OF TOMATO GROWN UNDER SALT STRESS

Tomato (Lycopersicon esculentum Mill.) yields are known to decrease for plants grown in saline soils. This study was conducted to determine the effects of arbuscular mycorrhizal fungi (AMF) inoculation on fruit yield and mineral content of salt-tolerant and salt-sensitive tomato cultivars grown with varied levels of salt. NaCl and CaCl₂were added to soil in the irrigation water in equal molar ratios to give EC_e values of 1.4 (nonstressed) and 4.9 dS m^?1 (salt stressed). Plants were grown in a greenhouse using unsterilized, low phosphorus (P) (silty clay) soil-sand mix. Mycorrhizal root colonization occurred whether cultivars were salt stressed or nonstressed, but the extent of AMF root colonization was higher in AMF inoculated than uninoculated plants. The salt tolerant cultivar ‘Pello’ generally had higher AMF root colonization than the salt sensitive cultivar ‘Marriha’. Shoot dry matter (DM) yield, fruit fresh yield, and AMF colonization were higher for plants grown under nonstressed than for plants grown under salt stressed conditions. Shoot DM and fruit fresh yields were higher in AMF inoculated than uninoculated plants grown with or without salt stress. Pello generally had higher fruit fresh yield per plant and fruit weight than Marriha, but these differences were only significant for fruit weight in unioculated plants grown under salt stressed conditions. The enhancement in fruit fresh yield due to AMF inoculation was 26 and 23% under nonstressed and 28 and 46% under salt stressed treatments for Pello and Marriha, respectively. For both cultivars, fruit contents of P, potassium (K), zinc (Zn), copper (Cu), and iron (Fe) were higher in AMF inoculated compared with uninoculated plants grown under nonstressed and salt stressed conditions. Fruit Na concentrations were lower in AMF inoculated than uninoculated plants grown under salt stressed conditions. The enhancement in P, K, Zn, Cu, and Fe acquisition due to AMF inoculation was more pronounced in Marriha than in Pello cultivar under salt stressed conditions. The results of this study indicated that AMF inoculated plants had greater tolerance to salt stress than unioculated plants.     

钙对盐胁迫下水稻幼苗抗氧化酶活性和膜脂过氧化作用的影响

研究了外源Ca2 对盐胁迫下耐盐性不同的两个水稻品种(武育粳3号和IR36)几种抗氧化酶活性及膜脂过氧化的影响。结果表明:适量的Ca2 供应能有效提高水稻叶片超氧化物歧化酶(SOD)、过氧化氢酶(CAT)、过氧化物酶(POD)以及抗坏血酸过氧化物酶(APX)的活性,使之维持在较高的水平上,并降低了丙二醛(MDA)含量和细胞膜透性。此外,外源Ca2 还增加了抗坏血酸(AsA)的含量,增强了水稻幼苗的根系活力。这表明适量的外源Ca2 供应提高水稻耐盐性的原因之一,在于其增强了植株的活性氧清除能力以及对细胞膜的稳定作用。     

PISTACHIO RESPONSES TO SALT STRESS AT VARIED LEVELS OF MAGNESIUM

Crop production in many parts of the world is increasingly affected by soil salinization, especially in the irrigated fields of arid and semi-arid regions. The effects of four magnesium levels [0, 0.5, 1, and 22 millliMolar (mM) magnesium as magnesium sulfate (MgSO₄.5H₂O)], and three salinity levels [0, 45 and 90 mM sodium chloride (NaCl)] on growth and the chemical composition of pistachio seedlings (Pistacia vera L.) cv. ‘Badami-e-Zarand’ was studied in sand culture under greenhouse conditions. The experiment was set up as a completely randomized design (CRD) with four replications. After 28 weeks the growth parameters of biomass, leaf number, leaf area and stem height were measured. The results demonstrated that salinity decreased biomass, leaf area and stem height; the application of 2 mM magnesium (Mg) significantly reduced biomass, leaf number, leaf area and stem height; salinity stress increased concentrations of sodium (Na) and potassium (K) in shoot as well as Na concentration in root; however, it decreased Mg and calcium (Ca) concentrations in shoot, as well as Mg, Ca, and K concentrations in root. The application of 2 mM Mg reduced K and Ca concentrations in shoot and Na and K concentrations in root.     

种子引发对NaCl胁迫下小麦幼苗生理特性的影响

以耐盐性强的晋农207和耐盐性弱的运麦218两个冬小麦品种种子为试材,用20%的PEG及100mmol/L的KNO3水溶液对种子进行引发处理.研究模拟NaCl胁迫环境下引发处理对小麦种子发芽、幼苗耐盐性及幼苗生理特性的影响.结果表明:两种引发处理不同程度地提高了2个品种小麦的发芽势、发芽率、发芽指数和活力指数;使2个小...     

地下水作用条件下土壤积盐规律研究

用粉砂壤土土柱进行了为期一年的室内模拟试验 ,对不同地下水埋深及其矿化度作用条件下 0～ 40cm深度土壤的盐分运动规律进行了深入研究。地下水埋深 85cm、1 0 5cm情况下 ,0～ 40cm深度土壤电导率与地下水矿化度呈良好正相关关系。地下水埋深 1 5 5cm、试验设定条件下 ,各土柱 0～ 40cm深度土壤积盐强度都较小 ,并且相互之间差异不明显。获得了各土柱 0～ 40cm深度土壤电导率关于地下水埋深、地下水矿化度的统计模型。对土壤电导率动态规律进行了深入分析 ,并建立了地下水明显影响到该深度土壤后土壤电导率动态模型。     

EFFECT OF PACLOBUTRAZOL AND PUTRESCINE ON ANTIOXIDANT ENZYMES ACTIVITY AND NUTRIENTS CONTENT IN SALT TOLERANT CITRUS ROOTSTOCK SOUR ORANGE UNDER SODIUM CHLORIDE STRESS

The effects of paclobutrazol (PBZ) and putrescine (Put) on antioxidant enzymes activity, proline contents and nutrients uptake were studied on salt tolerant citrus rootstock sour orange. Six-month-old nucellar seedlings grown in pots and subjected to three levels of PBZ and two levels each of salinity and Put for 90 days. Seedlings treated with PBZ or Put alone or in combination had higher anti-oxidant enzymes activities, accumulation of proline and nutrients contents like potassium (K⁺) and calcium (Ca²⁺) under both saline and non-saline conditions. Further, application of PBZ or Put alone or in combination also reduced the accumulation of both Na⁺ and Cl^? ions in leaves and roots in NaCl stressed seedlings. A combined application of 250 mg L^?1 PBZ and 50 mg L^?1 Put proved to be more effective in improving proline and Ca²⁺ content and restricting accumulation of Na⁺ ions in leaf tissues.     

地下水作用条件下粉砂壤土盐分动态研究

用粉砂壤土土柱进行了室内模拟试验，研究不同地下水埋深及其矿化度作用条件下非饱和粉砂壤土的盐分动态规律。在相同地下水埋深情况下，处于盐分动态平衡状态时的各模拟土柱相同层次土壤溶液浓度，与地下水矿化度呈良好正相关关系。在相同地下水矿化度条件下，土体积盐速率与地下水埋深呈负相关关系，但是各土柱相同埋深土体达到盐分动态平衡状态时的土壤溶液浓度差别不明显。对地下水埋深及地下水矿化度对耕作层土壤溶液浓度的综合作用效果进行了深入分析，建立了各积盐阶段耕作层土壤溶液浓度的增高值关于此二因素的数理统计模型。     

EFFECTS OF MYCORRHIZAL FUNGI ON TOLERANCE CAPABILITY OF CORN GROWN UNDER SALT STRESS CONDITION

A greenhouse experiment was conducted to determine the effect of salinity on the efficacy of two arbuscular mycorrhizal fungi (AMF), Glomus mossea and natural mycorrhiza, of Glomus species, was investigated in terms of growth and nutrition of corn plant (Zea mays L). Plants were grown under different salinity levels imposed by 2.0, 2.5, 3.5, 5.0, 8.0, 12.0 dS m^?1of Hoagland's Solution [sodium chloride (NaCl), sodium sulfate (Na₂SO₄)_, Calcium dichloride (CaCl₂), and magnesium sulfate (MgSO₄) 7:9:3:1 ratio, respectively]. Both types of mycorrhizal fungi did not display significant protection in the host plant against the detrimental effects of the soil salinity. The effect of inoculation on growth varied only with the level of salinity. Maximum root colonization and spore numbers were observed in plants cultivated with low salinity levels. It was found that significant interaction between AMF x Salinity level for calcium (Ca), magnesium (Mg), iron (Fe), zinc (Zn), and manganese (Mn) of shoot, and for Zn and Mn, of root.     

RESPONSE OF CHICKPEA TO NITROGEN SOURCES UNDER SALINITY STRESS

Abstract

In vitro‐grown Chrysanthemum morifolium Ramat. cultivars Bright Golden Anne, Deep Luv, and Lucido were exposed to elevated mannitol, sucrose, or sorbitol concentrations to see if their response to this osmotic stress mimics that of in vivo plants enduring water deficit. The relative efficacy of the three osmotic agents at manifesting a response was also evaluated. Tissue osmolarity paralleled media mannitol and sorbitol concentration for all three cultivars. Shoot growth correspondingly decreased with increased osmolarity applied during the rooting phase. These responses generally resembled those of water‐stressed greenhouse plants. The degree of response varied with cultivar; ‘Lucido’ was the most sensitive and ‘Bright Golden Anne’ the least. Sucrose (metabolized by the plants) failed to elicit consistent osmotic stress symptoms; instead it enhanced both shoot and root growth. In vitro stress‐induced symptoms were produced in both proliferation and rooting stages, but consistent shoot growth reduction with increasing levels of incorporated osmotic agent was only observed during rooting. Plants did not retain the osmotic adjustment when they were subsequently subcultured from the stress treatments back to the control medium.     

阿特拉津污染胁迫下土壤微生物生物量对外源有机无机物质的响应

土壤微生物与土壤自净作用密切相关,它直接参与土壤动植物残体、外来有机物质和其它有毒有害有机化合物的降解过程。然而,这些有机物质的存在也同样会影响土壤微生物的活性及其多样性[1] 。土壤生物学性质能敏感地反映出土壤质量和健康的变化,是土壤质量评价不可缺少的指标[2 ]