Growth Properties and Ion Distribution in Different Tissues of Bread Wheat Genotypes (Triticum aestivum L.) Differing in Salt Tolerance

Four bread wheat genotypes differing in salt tolerance were selected to evaluate ion distribution and growth responses with increasing salinity. Salinity was applied when the leaf 4 was fully expanded. Sodium (Na⁺), potassium (K⁺) concentrations and K⁺/Na⁺ ratio in different tissues including root, leaf‐3 blade, flag leaf sheath and flag leaf blade at three salinity levels (0, 100 and 200 mm NaCl), and also the effects of salinity on growth rate, shoot biomass and grain yield were evaluated. Salt‐tolerant genotypes (Karchia‐65 and Roshan) showed higher growth rate, grain yield and shoot biomass than salt‐sensitive ones (Qods and Shiraz). Growth rate was reduced severely in the first period (1–10 days) after salt commencements. It seems after 20 days, the major effect of salinity on shoot biomass and grain yield was due to the osmotic effect of salt, not due to Na⁺‐specific effects within the plant. Grain yield loss in salt‐tolerant genotypes was due to the decline in grain size, but the grain yield loss in salt‐sensitive ones was due to decline in grain number. Salt‐tolerant genotypes sequestered higher amounts of Na⁺ concentration in root and flag leaf sheath and maintained lower Na⁺ concentration with higher K⁺/Na⁺ ratios in flag leaf blade. This ion partitioning may be contributing to the improved salt tolerance of genotypes.     

不同小麦品种芽期耐盐性鉴定研究

为研究不同小麦品种在芽期的耐盐性,本研究以6 种小麦品种为研究对象,用不同浓度NaCl （盐浓度分别为0%(CK)、1%、1.5%、2.0%）胁迫处理后,分别测定并分析小麦芽期的发芽率、芽长、根长、芽鲜重。试验结果表明：在盐胁迫下,不同小麦品种随着盐浓度的升高,小麦的发芽率、芽长、根长、芽鲜重都随之降低。其中,在高盐(1.5% NaCl)处理下,‘宁春4 号’、‘Drasdal’在芽期比较敏感,‘红芒麦’、‘毛火麦’在芽期表现出一定的耐盐性,‘宁春27号’、‘山融3号’表现出比较强的耐盐性。因此,在高盐胁迫下‘宁春27号’、‘山融3号’芽期具有较强的耐盐性。     

春小麦田间盐胁迫下的农艺性状表现研究

盐害是制约小麦生产的主要因素,为研究小麦重组自交系后代在田间盐环境的耐盐性。本研究以2个小麦品种‘宁春27号’、‘宁春4号’以及2个亲本杂交后代中8个小麦品系‘R9’、‘R32’、‘R39’、‘R75’、‘R88’、‘R89’、‘R103’、‘R108’、‘R117’、‘R129’、‘R130’为研究对象,在田间盐环境下通过对全生育期的农艺性状进行调查分析对其耐盐性进行评价。试验结果表明:在全盐含量为0.35%的田间盐环境下,通过对试验材料进行株高、穗长、穗重、穗粒数、小区产量进行调查分析,‘R32’株高最高,明显高于亲本,‘R75’的穗长、穗重、穗粒数都明显高于其亲本,‘R88’、‘R108’的小区产量最高,明显高于其亲本。因此,通过田间表现及农艺性状比较,‘R75’、‘R88’、‘R108’田间耐盐性较强。     

引进春小麦种质耐盐性的鉴定评价

对从美国引进的28份春小麦种质经过实验室耐盐性鉴定,筛选出13份芽期相对盐害率在20%以下,苗期盐害指数在40%以下的耐盐性较强的材料,进一步在0.37%以上的盐渍化土壤上进行全生育期的耐盐性鉴定,对株高、穗长、穗数、穗粒数、千粒重等生产要素进行统计分析及逐步剔除多元回归分析,结果表明产量性状的耐盐指数与出苗率、     

Differences in Ion Accumulation and Salt Tolerance among Glycine Accessions

Salinity reduces crop yield by limiting water uptake and causing ion‐specific stress. Soybean [Glycine max (L.) Merr.] is sensitive to soil salinity. However, there is variability among soybean genotypes and wild relatives for salt tolerance, suggesting that genetic improvement may be possible. The objective of this study was to identify differences in salt tolerance based on ion accumulation in leaves, stems and roots among accessions of four Glycine species. Four NaCl treatments, 0, 50, 75 and 100 mm , were imposed on G. max, G. soja, G. tomentella and G. argyrea accessions with different levels of salinity tolerance. Tolerant genotypes had less leaf scorch and a greater capacity to prevent Na⁺ and Cl^? transport from soil solution to stems and leaves than sensitive genotypes. Magnitude of leaf injury per unit increase in leaf Na⁺ or Cl^? concentrations was lower in tolerant than in susceptible accessions. Also, plant injury was associated more with Na⁺ rather than with Cl^? concentration in leaves. Salt‐tolerant accessions had greater leaf chlorophyll‐meter readings than sensitive genotypes at all NaCl concentrations. Glycine argyrea and G. tomentella accessions possessed higher salt tolerance than G. soja and G. max genotypes.     

Screening a Wheat Collection for Leaf Position at Different Stages of Growth

A collection of hexaploid -wheat consisting of 1400 entries from 36 countries was screened for leaf position at four stages of growth over two years. At the shooting stage, more than 80 % of the entries showed the curved position of the flag and the second leaf, about 15 % the erect position, while the horizontal position did not occur. At the heading stage more than 10 % of the genotypes with curved and some with erect position assumed horizontal position. At the milk stage, half of the genotypes with the erect position in earlier stages of growth assumed horizontal and even pendulous position; the majority of genotypes had curved position of leaves. At the dough stage, only about 2 % of the genotypes maintained erect flag leaf position, while 45 % had curved and about 45 % pendulous position of leaves. When an erect leaf assumes horizontal position, the lamina is completely straight without any curving, which is different from genotypes classified as having horizontal position at heading and milk stage. The position of the second leaf, in general, followed the pattern of the flag leaf. Through the stages of growth the curved position was more stable than either erect or horizontal positions. Leaves were more erect and stable in position under conditions with lower rainfall and higher temperatures (1983) than in the rainy year with lower temperatures (1984). Most of the high-yielding cultivars with short straw had a curved position, which is probably the consequence of unintended selection to fit a dense canopy.     

水稻籼型不育系萌发期和幼苗期的耐盐性评价

为了鉴定水稻籼型不育系在不同生育阶段的耐盐性,筛选出适合耐盐杂交水稻新组合测配的强耐盐不育系,笔者分别在萌发期、幼苗期对8个水稻籼型不育系进行耐盐性鉴定,以耐盐品种FL478、盐敏感品种IR29为对照。结果显示：盐胁迫对水稻种子的萌发起到抑制作用,抑制效应随盐浓度的提高而增强,10 g/L NaCl浓度胁迫能较好反映水稻不育系萌发期耐盐性的差异。‘沪旱7A’、Y58S在萌发期的耐盐性最好,与FL478均属于1级,具极强的耐盐性;‘荃9311A’的盐害级别为3级,具强耐盐性。盐胁迫对水稻幼苗的生长也起到明显的抑制作用,8 g/L NaCl浓度胁迫下的枯叶率性状能较好反映水稻不育系幼苗期耐盐性的差异,‘沪旱11A’与耐盐对照FL478耐盐性相仿。     

Indices of Drought Tolerance in Wheat Genotypes at Early Stages of Plant Growth

Thirty diverse genotypes of bread wheat were evaluated for seed vigour index, germination percentage, root length, shoot length, root‐to‐shoot length ratio, coleoptile length and osmotic membrane stability under laboratory conditions. Considerable variation was observed for all the characters. Discrimination among the genotypes on the basis of mean values was better under normal than under moisture stress conditions, indicating suppression of variability under moisture stress conditions. Comparison of mean performance under normal and osmotic stress conditions indicated that the seed vigour index was the most sensitive trait, followed by shoot length, germination percentage and root length. The root‐to‐shoot length ratio, however, increased under osmotic stress. The magnitude of genetic components of variance and heritability were, in general, lower under osmotic stress than under normal conditions. All the characters except germination percentage, shoot length and coleoptile length showed considerable genetic variability. Heritability in the broad sense was also moderate to high for all the characters under both environments. Due to high heritability and genetic advance great benefit from selection can be expected for the osmotic membrane stability of leaf segments and root‐to‐shoot length ratio. Moderate progress can be expected from root length and seed vigour index. Correlation studies indicated that the osmotic membrane stability of the leaf segment was the most important trait, followed by root‐to‐shoot ratio and root length on the basis of their relationships with other traits.     

两个小麦新品种的耐盐性分析

为了研究不同浓度NaCl胁迫对小麦生理特性及TaNHX1基因表达的影响,以鲁原502和青麦6号2个小麦新品种为试验材料,50,100,150,200 mmol/L NaCl胁迫下测定2个小麦品种种子发芽率、幼苗鲜质量、根系活力、质膜透性、MDA含量、Na~+含量等生理指标,并通过荧光定量PCR方法对小麦耐盐基因TaNHX1在根部和茎基部的表达量进行了比较。结果表明,100 mmol/L以上浓度NaCl胁迫下青麦6号种子发芽率显著高于鲁原502;低浓度NaCl胁迫对青麦6号幼苗生长具有显著促进效应,150 mmol/L NaCl胁迫下青麦6号幼苗鲜质量显著降低,而鲁原502幼苗鲜质量在100 mmol/L NaCl胁迫下就开始显著降低;高浓度NaCl胁迫下鲁原502根系活力下降幅度显著大于青麦6号;相同浓度NaCl胁迫下鲁原502叶片质膜透性和MDA含量均显著高于青麦6号,说明NaCl胁迫对青麦6号叶片细胞质膜伤害较小;高浓度NaCl胁迫下青麦6号根部和茎基部Na+含量均显著高于鲁原502,说明青麦6号根部和茎基部的拒Na+能力显著大于鲁原502,可以有效限制Na+向地上部运输;鲁原502和青麦6号的TaNHX1基因分别在100,150 mmol/L NaCl胁迫下达到最高表达量。以上结果说明青麦6号比鲁原502更耐盐,鲁原502的最高耐盐浓度为100 mmol/L,青麦6号的最高耐盐浓度为150 mmol/L。     

耐盐性不同的近等基因系小麦生理性状的比较研究

比较耐盐性不同的近等基因系小麦在盐胁迫 (1%NaCl)条件下 ,其超氧化物歧化酶 (SOD)活性、丙二醛 (MDA)含量以及叶片质膜透性这几个生理指标的变化 ,结果表明 ,盐胁迫条件下 ,耐盐性强的RH870 6 - 49材料SOD活性显著低于耐盐性差的H870 6 - 34,丙二醛 (MDA)含量以及叶片质膜透性也显著低于耐盐性差的H870 6 - 34     

Responses of Some Newly Developed Salt-tolerant Genotypes of Spring Wheat to Salt Stress: 1. Yield Components and Ion Distribution

The degree of salt tolerance of two newly developed genotypes of spring wheat, S24 and S36 was assessed with respect to their parents, LU26S (from Pakistan) and Kharchia (from India). These four lines along with a salt-tolerant genotype SARC-1 and two salt-sensitive cvs Potohar and Yecora Rojo were subjected to salinized sand culture containing 0, 125 or 250 mol m^?3 NaCl in full strength Hoagland's nutrient solution. S24 produced significantly greater grain yield and had greater 1000 seed weight and number of tillers per plant than those of the other cultivars /lines. S36 was not significantly different from its parents in seed yield and yield components. SARC-1 was the second highest in grain yield of all cultivars/lines, but it did not differ significantly from LU26S and Kharchia in 1000 seed weight and number of tillers per plant. The greater degree of salt tolerance of S24 could be related to its lower accumulation of Na⁺ in the leaves and maintenance of higher leaf K/Na ratios and K versus Na selectivity as compared to its parents. S36, which was as good as its parents in growth, also had lower Na⁺ and higher K/Na ratios and K versus Na selectivity in the leaves at the highest salt level than those in its parents. SARC-1 did not differ from LU26S and Kharchia in ionic content or K/Na ratios and K versus Na selectivities of both leaves and roots. Both the salt-sensitive cultivars, Potohar and Yecora Rojo, had significantly greater leaf Na⁺ and Cl^? concentrations and lower leaf K/Na ratios and K versus Na selectivities than all the salt-tolerant lines examined in this study. From this study it is evident that improvement in salt tolerance of spring wheat is possible through selection and breeding, and pattern of ion accumulation is not consistent among the salt-tolerant genotypes in relation to their degree of salt tolerance.     

不同品种玉米萌发期耐盐性的比较

为了对玉米品种耐盐性筛选、盐碱地玉米栽培和耐盐育种提供理论参考,以发芽势、发芽率、根长和苗长等作为指标,用不同浓度的NaCl对9份不同玉米品种进行苗期耐盐性筛选的鉴定,分析盐胁迫对不同品种玉米种子萌发的影响。结果表明：30 mmol/L NaCl处理下‘吉单519’和‘平全9’的根长比对照增加了31.17%和14.17%,与对照处理达到显著水平（P<0.05）,说明低浓度的NaCl（≤30 mmol/L）溶液对玉米的萌发有促进作用,提高了玉米种子的发芽率和根、芽的伸长,并且不同品种间表现出耐盐性有差异。     

利用SOM聚类分析及主成分分析方法鉴定小麦品种萌发期耐盐性

为了研究不同小麦品种萌发期的耐盐性,为小麦萌发期耐盐性鉴定提供快速、准确的鉴定方法和理论依据.本研究以40个冬小麦品种为试验材料,通过主成分分析法(PCA)与神经网络自组织映射(SOM)聚类分析法,研究盐胁迫对40个小麦品种萌发期各项形态指标的影响.主成分分析法结果表明,发芽势、发芽率、最长根长、第一片叶长及胚芽鞘长在...     

Responses of Some Local/Exotic Accessions of Lentil (Lens culinaris Medic.) to Salt Stress

Assessment of salt tolerance at all growth stages is crucial to determine the overall tolerance of a crop. Salt tolerance of five tolerantILL 5845, ILL 6451, ILL 6788, ILL 6793 andILL 6796, three moderately tolerant ILL 6431. ILL 6770 andILL 6784, and three sensitiveILL 6210, ILL 6439 andILL 6778 accessions selected at the germination and seedling stages was assessed at the adult stage using sand culture sahnized with 0, 30, or 60 mol m^?3 NaCl. A positive correlation was observed between degrees of salt tolerance at different growth stages in three tolerant accessionsILL 6451, ILL 6788 andILL 6793 which produced significantly higher seed yield than the other accessions. This was also affirmed in three sensitive and two moderately tolerant accessions (ILL 6770 andILL 6784) whose salt sensitivity was conferred consistently at all growth stages. In contrastILL 5845, andILL 6796 which were highly salt tolerant andILL 6431 which was moderately tolerant at the early growth stages had relatively low seed yield, hence showing a negative correlation between tolerances at different growth stages. High yielding accessionsILL 6451, ILL 6788 andILL 6793 in general, accumulated higher Na⁺ and higher or moderate Cl^? in their shoots compared with the other accessions, thus showing a typical halophytic mechanism of salt inclusion. K/Na ratios of all the tolerant, moderately tolerant and sensitive accessions exceptILL 6784 andILL 6778 were less than 1, a suggested minimum level for normal functioning of many metabolic processes in plants. The present study shows that salt tolerance observed previously at the early growth stages is conferred at the adult stage in most of the accessions of lentil examined here; but for others in which no positive correlation was observed between different growth stages suggests that a combination of certain characters can be used as selection criterion for improving salinity tolerance in lentil through exploitation of inter- and intra-cultivar/line variation.     

春小麦耐热性的筛选方法与指标

利用５１份春小麦材料对３种耐热性方法进行了研究评价。供试材料在田间通过晚播计算各基因型的粒重感热指数（Ｓｅ）或于籽粒浆期用塑料简棚进行遮盖处理并计算千料重感热指数（Ｓｇ）评价其耐热性，而在室骨采用膜热稳定性测定方法，以相对热损伤率（ＲＩ％）大小评价基因型的耐热性。相关分析表明：Ｓｅ在年际间和年份内的相关系数均呈极显著高度正相关，从而具有较好的重演性，而ＲＩ％与Ｓｇ呈显著正相关说明基因型的热稳定性大     

盐胁迫下不同基因型棉花萌发生长和离子吸收特性

在 0、1 0 0、2 0 0 mmol· L- 1Na Cl处理下 ,对棉花耐盐性差异较大的两个基因型枝棉 3号和泗棉 2号的萌发特性、盐分吸收以及棉花幼苗性状进行了研究。结果表明 ,在 2 0 0 mmol· L- 1Na Cl胁迫 7d后 ,两基因型种子的含水量和子叶 K+含量没有显著差异 ,但耐盐较强品种枝棉 3号 Na+、Cl- 含量和电导率明显低于耐盐较弱品种泗棉 2号。盐胁迫下枝棉 3号幼苗性状显著好于泗棉2号     

不同水稻品系芽期耐盐性比较分析

为研究不同水稻品系在芽期耐盐性,为今后培育耐盐品种提供优良种质资源,本研究以7个水稻品系为实验材料进行芽期耐盐试验,用不同浓度NaCl（盐浓度分别为0、0.125、0.15、0.2 mol/L）胁迫后,对水稻的发芽势、发芽率、根长、芽长、芽鲜重以及主根数目进行测定分析,并通过多元分析对各品种相关指标进行统计分析。试验结果表明：随着盐浓度的升高,不同水稻品系的各项指标均有不同程度的降低。其中,0.15 mol/L盐处理下,‘S83’,‘S85’号水稻品系表现出一定的耐盐性,‘S88’号水稻品系表现出较强的耐盐性。多元统计分析结果表明,在高盐胁迫下‘S88’号水稻品系具有较强的耐盐性。     

盐胁迫下不同小麦品种(系)旗叶衰老特性分析

为明确盐胁迫对不同小麦品种(系)的旗叶衰老特性的影响,笔者选取了7个小麦品种(系),进行了盐碱地条件下旗叶衰老指标的研究。结果表明,随着花后小麦生育期的推移,不同小麦品种(系)在盐碱胁迫下旗叶中的SOD、POD、MDA、游离脯氨酸含量均存在显著差异,但其变化幅度不一致,MDA含量、脯氨酸含量呈现不同程度的增加,‘青麦w04’、‘青麦6号’、‘德抗911’旗叶中的MDA含量增加幅度较小,但脯氨酸含量增加幅度较大。SOD活性呈现不同幅度的下降,‘青麦w04’、‘青麦6号’、‘德抗911’花后旗叶中的SOD活性下降幅度较小。POD活性呈现先上升后下降趋势,开花14天后‘青麦w04’、‘青麦6号’、‘德抗961’旗叶中的POD活性下降速度较慢。可得出结论,盐碱胁迫下‘青麦w04’、‘青麦6号’、‘德抗961’的衰老程度相对较低,耐盐能力相对较强。     

Reproductive Compensation of Cotton after Salt Stress Relief at Different Growth Stages

Differential salt sensitivity during growth stages and reproductive compensation of plants after salt stress relief are important factors for adopting appropriate irrigation strategies with saline waters. Consequently, recovery of cotton after exposure to different levels of salt stress was evaluated. An outdoor, sand culture experiment was conducted with cotton. Water salinities were 2, 10 and 20 dS m⁻¹, and the growth phases were vegetative (G1), reproductive (G2) and boll development (G3). G1 and G3 were the least and the most salt tolerant phases, respectively. The significant yield reduction in all of the saline water treatments as compared to control was mainly due to the reduction in number of bolls per plants. In general, cotton plants were capable of producing seed cotton under salt stress, as well as, after salt stress relief. However, as the salt stress severity increased the ability of cotton to compensate yield loss decreased. Irrigation of cotton at G1 stage with either moderate (10 dS m⁻¹) or high (20 dS m⁻¹) salinity waters should be avoided. Moderate saline water could be applied either at G2 or G3 stage. High salinity water can be used for irrigation only at G3 stage to produce acceptable cotton seed yield.