Differences in dry matter production,grain production,and photosynthetic rate in barley cultivars under long-term salinity

Soil salinity is a major environmental stress causing significant loss of crop productivity. Barley (Hordeum vulgare L.) is one of the few field crops that can grow in salt-affected fields and varietal differences in productivity under salinity conditions were known. To clarify the trait most responsible for grain production under salt stress, barley cultivars that were salt tolerant (OUE812) or salt sensitive (OUC613) were grown from seedling to harvest stage in vermiculite containing various concentrations of NaCl. Dry weight of aboveground parts and grain weight decreased significantly with increasing NaCl concentration. The dry weight of the aboveground parts and grain weight decreased more significantly in OUC613 than in OUE812 for plants treated with 150 mM and 200 mM NaCl. A marked reduction in ripening percentage caused significantly decreased grain production in OUC613 as compared with OUE812. In plants treated with 200 mM NaCl, the photosynthetic rate decreased three weeks after starting the NaCl treatment, but a significant difference between cultivars in photosynthetic rate did not appear until seven weeks of NaCl treatment. OUE812 kept a higher photosynthetic rate during ripening than did OUC613 and dry matter production during the period from ripening to harvest was significantly larger in OUE812 than in OUC613. Keeping a higher photosynthetic rate might have contributed to higher grain production in OUE812. Higher ripening percentage and higher rate of photosynthesis during ripening might be target traits in breeding to improve the tolerance of barley to long-term salt stress.     

大豆抗腐霉根腐病的生理差异研究

腐霉根腐病是大豆主要的土传病害,为揭示抗感病大豆品种的生理差异,对不同抗性品种在腐霉病原菌侵染下的大豆下胚轴中丙二醛、苯丙氨酸解氨酶(PAL)、过氧化物酶(POD)、可溶性糖、脯氨酸含量的变化进行测定。结果表明:腐霉菌侵染后,抗病大豆品种下胚轴的丙二醛含量增加不十分明显;可溶性糖含量都是正向增加,苯丙氨酸解氨酶活性,过氧化物酶活性,脯氨酸含量在不同时段都有所增加且抗病品种明显高于感病品种。而感病品种在腐霉菌侵染条件下,大豆下胚轴中丙二醛含量累积较高,可溶性糖在某一时段内有所减少,苯丙氨酸解氨酶活性、过氧化物酶活性,脯氨酸含量增加幅度小于抗病品种,表明抗病品种具有较强的生理生化调节能力。     

Interactive Effects of Sodium and Potassium on the Growth and Photosynthesis of Spinach and Komatsuna

Abstract

Two cultivars of spinach and one cultivar of komatsuna were sand cultured using a nutrient solution with Na and K in various combinations. The growth (fresh weight of shoot) of spinach cv. Atlas was significantly increased when 1.4 mM KC1 of the 7 m M KO was replaced with 1.4 mM NaCl, although the growth was reduced when more KC1 was replaced with NaCl. In another spinach cv. All Right, however, NaCl substituting for 20% of KC1 showed no significant effects. In komatsuna, Na used in place of K at any ratio reduced the growth. The growth of spinach cv. Atlas was increased by applying 20 mM NaCl, irrespective of K dose (480 - 2400 mg K₂O per 1/2000 a Wagner pot). The growth of spinach cv. All Right was also increased by 20 mM NaCl when K was at a deficient level (480 - 960 mg K20 per pot), but was not when K was at: an excessive level (1920 - 2400 mg K₂O per pot). In komatsuna, 20 mM NaCl reduced the growth. In spinach, Na prevented the decrease of the photosynthetic rate and stomatal conductance caused by K deficiency.     

淹水缓解直播早籼稻苗期低温冷害的生理特性研究

[目的]探究淹水对低温胁迫下直播早籼稻幼苗生长的影响,为南方稻区直播稻生产与抗逆栽培奠定生理基础.[方法]以耐冷品种湘早籼6号和冷敏感品种中嘉早17为材料,设置低温处理(8℃)、低温淹水处理(8℃+淹水)与常温对照(25℃)3个处理(处理3 d),分析秧苗农艺性状、抗氧化酶活性、渗透调节物质含量、光合酶活性和内源激素含...     

荔枝花芽分化期间光合特性与碳氮物质变化

荔枝花芽分化分为诱导、发端和分化3个阶段。试验以早中熟品种‘妃子笑’和中熟品种‘桂味’为试材,对荔枝花芽分化不同物候阶段叶片净光合速率(Pn)、叶绿素指数(SPAD)、荧光参数和碳氮物质等生理指标的变化规律进行研究。结果表明：‘妃子笑’的成花进程早于‘桂味’品种,但2个品种在整个花芽分化期间的相关生理指标均呈相似变化趋势,Pn和SPAD在诱导期和抽穗期水平较低,“白点”期和花蕾期有所增加,而荧光参数恰好相反;荔枝成花期间,其可溶性总糖含量在“白点”期阶段水平最低,而淀粉和总氮含量呈相反趋势,在“白点”期达到最高值。可见,不同荔枝品种的光合特性与碳氮物质变化受其花芽分化的阶段性影响更大,而“白点”期是荔枝碳氮物质变化较为关键的转折点。     

叶面喷施吲哚乙酸对油菜蕾薹期渍水的缓解效应

以油菜品种秦优7号(敏感)和苏油4号(耐渍)为材料,通过盆栽试验研究吲哚乙酸(IAA)对油菜蕾薹期渍水的缓解效应。蕾薹期渍水持续10d,渍水结束后,叶面喷施浓度为0.1mmol/L的IAA,随后的0~15d调查油菜的生理变化。结果发现:渍水后生物量和叶片光合色素含量降低;谷胱甘肽、抗坏血酸含量和超氧化物歧化酶活性升高;丙二醛含量升高;蔗糖合成酶、蔗糖磷酸合成酶活性上升,蔗糖和可溶性糖含量增加。渍水结束后喷施IAA,对敏感的秦优7号缓解效应更明显;叶片中的光合色素含量升高,5d后显著恢复生长;蔗糖磷酸合成酶活性降低,降低蔗糖含量;蔗糖合成酶活性降低,减少蔗糖的分解;尤其是喷施15d后IAA对渍水胁迫的缓解作用最明显,苏油4号根干重显著增加,而秦优7号的根干重和茎干重均显著增加。叶面喷施IAA有效缓解单株角果数、每角粒数和产量的降低,但对抗氧化系统影响较小。     

Net photosynthetic rate of potato at high temperatures

Summary Potato cultivars were grown in a glasshouse and plants periodically transferred to a growth chamber. When the ambient temperature in the growth chamber was raised from 15 to 40°C in steps of 5°C per hour, net photosynthetic rate decreased at temperatures above 20°C. At 40°C the rate was 37% of the rate at 20°C. A greater decrease in net photosynthetic rate occurred with plants of the cultivar Up-to-Date than with cultivars R100 and BP13. Low values of leaf diffusive resistance were recorded and changes in photosynthetic rate could not be explained by changes in this factor. When a constant ambient air temperature of 20°C was maintained while soil temperature was increased, net photosynthetic rate decreased.     

Significance of the fructose/glucose ratio in screening potato breeding lines with processing potential

Low sugar accumulation during low temperature holding is a most sought after characteristic in a potato cultivar utilized for processing. Although this property is largely inherited, the lack of a reliable biochemical test capable of screening large numbers of new breeding lines with low sugar accumulating ability has hampered present selection procedures of plant breeders. This study examined the concentration of individual sugar components and the ratios of sugar components from 80 to 110 day-old plants of three commercial potato cultivars, White Rose, Russet Burbank and Norchip, each with different inherent capacity to accumulate sugars under low temperature holding. By determining the fructose and glucose concentration of potatoes from 110-day old plants and calculating the fructose/ glucose ratio, it was possible at harvest to separate cultivars that accumulate high concentrations of sugars during cold storage from those that accumulate low concentration of sugars     

Relative salinity tolerance of potato cultivars assessed byin vitro screening

One hundred and thirty European and North American potato cultivars were assayedin vitro for salinity (NaCl) tolerance. A modified single-node cutting bioassay was used in which cultivars were exposed to a range of NaCl levels (0, 40, 80, and 120 mM), in a Murashige and Skoog-based medium, for 1 month. Evaluations were performed twice for each cultivar at each salt level, using five single-node cuttings. Six vegetative growth parameters (shoot and root lengths, fresh and dry weights) were measured at the time of harvest and corrected for differences in cultivar vigor. These relative values were subjected to multivariate cluster analysis. The sum of the relative rankings at 40, 80, and 120 mM NaCl partitioned the cultivars into 8 units. The cultivars Amisk, BelRus, Bintje, Onaway, Sierra, and Tobique were in the most salinity tolerant unit and in the top cluster group for vigor with the exception of Tobique. These cultivars can be recommended for further study.     

冬小麦叶片显微结构和光合特性与产量的关系

为了解冬小麦叶片显微结构和光合特性与产量的关系,采用大田跟踪对比调查方法,对8个高产冬小麦品种的叶片显微结构、光合特征及产量性状进行分析。结果表明,小麦不同叶位叶片主要由规则环状细胞组成,各叶位叶片规则细胞的平均环数为1.7~4.5环。随叶位升高,叶肉细胞平均环数及上表皮和下表皮气孔密度均有增加的趋势。各品种旗叶叶绿素含量最大峰值出现在5月10日前后;旗叶可溶性蛋白含量变化与叶绿素含量变化相似,最大值陆续出现在5月7-20日。各品种叶片叶肉细胞平均环数和平均光合速率均以旗叶最高。但品种间光合势、叶源量的差异与叶肉细胞和叶绿素含量并不完全一致。品种间产量性状的差异主要表现在生物产量与经济系数上。生物产量与倒2叶光合势呈显著正相关,与倒3叶光合势呈极显著正相关。综上可见,光合性能好且光合产物能够有效转运进入籽粒,是小麦品种获取高产的必要特征。     

NaCl胁迫对不同耐盐性水稻某些生理特性和光合特性的影响

选取较耐盐的水稻品种‘HH11’、‘JX99’和盐敏感水稻品种‘YSXD’,设置6个土壤NaCl浓度处理(0、1、2、3、4 g/kg),在防雨棚下盆栽并培育至孕穗期,分析NaCl胁迫对不同耐盐性水稻生理生化及光合特性的影响,结果表明:(1)NaCl胁迫抑制水稻的生长,表现为随着NaCl浓度增加,水稻的株高逐渐降低,但在3～4 g/kg土壤含盐量下耐盐水稻的株高显著高于盐敏感水稻品种。(2)耐盐水稻和盐敏感水稻的可溶性总糖对NaCl胁迫的响应差异明显,在1～4 g/kg NaCl胁迫下,盐敏感水稻叶片可溶性总糖显著降低,但是耐盐水稻可溶性总糖大量合成并积累,并且显著高于盐敏感品种。(3)NaCl浓度增加迫使水稻叶片丙二醛不断积累,导致细胞膜透性逐渐增大,但是耐盐水稻丙二醛的积累量较少,细胞膜受盐害程度显著小于盐敏感水稻。(4)NaCl胁迫抑制了水稻光合速率,但不同的NaCl浓度下导致水稻品种光合速率下降的原因各有差异,其中在0～1 g/kg NaCl胁迫下盐敏感水稻光合速率降低是非气孔因素导致的,而在2～4 g/kg NaCl胁迫下是由气孔因素造成的;0～2g/kg盐浓度下耐盐水稻HH11的光合速率降低是非气孔因素导致的,3～4 g/kg盐浓度处理是由气孔因素导致的;气孔因素是0～4 g/kg盐处理耐盐水稻JX99的光合速率降低的主要原因。(5)盐胁迫下耐盐水稻的叶片蒸腾速率显著降低,并且显著低于盐敏感水稻,相反水分利用效率和气孔限制值却明显升高,并且显著高于盐敏感水稻品种,表明盐浓度增加迫使耐盐水稻气孔阻力增大,减少水分的流失,抑制了蒸腾速率,使耐盐水稻叶片保持较高的水势;同时提高了叶片水分利用效率,碳同化效率提高,以满足耐盐水稻正常代谢生理需求,进行正常生命活动。     

Physiological effects of psyllid (Paratrioza cockerelli) on potato

Feeding by psyllid nymphs causes “Psyllid yellows,” a characteristic yellowing of shoots which results in a dramatic loss of tuber yield. If psyllid infestation is not controlled, the onset of shoot yellowing and growth reductions can occur within two weeks. When insecticides are applied after yellowing, recovery of plants often is not complete. In this study comparisons were made of the physiology and growth of tops and tubers of recovered and permanently injured potatoes of the cultivars ‘Denali,’ ‘Kennebec,’ and ‘Norgold Russet.’ Permanently injured plants senesced rapidly, developed less shoot growth, aerial tubers and shortened and thickened internodes. They had lower tuber yields than plants that recovered. Permanently injured ‘Denali’ developed shoots on old flowering stems. In permanently injured plants of all cultivars, the tubers were small and badly misshapen but numbers increased. In recovered ‘Kennebec’ plants tubers were also misshapen, but were of average size. Tubers of recovered ‘Denali’ and ‘Norgold Russet’ were of acceptable shape. In samplings made during tuber growth, dry weight percentages of total soluble sugars, sucrose and glucose of tubers from permanently injured plants were found to be the same as those of recovered plants. In all cultivars, starch percentages of tubers from permanently injured plants were higher than that of the recovered, but the pattern of carbohydrate content changes was similar for permanently injured and recovered cultivars.     

施磷水平对小麦子粒蛋白质含量及根系生理特性的影响

为明确磷肥对小麦品质及根系发育的影响及调控,以强筋小麦郑麦9023、中筋小麦周麦18号、弱筋小麦郑麦004为材料,研究了3个磷肥水平对不同筋力型小麦子粒蛋白质含量和根系数量性状及生理生化特性的影响。结果表明,增施磷肥在不同程度上增加次生根数,提高根系活力,降低根中可溶性糖含量,但高磷并不利于根系生长。次生根数在子粒灌浆期达最高值,其中,郑麦004的单株次生根数和主茎次生根数较多。根系对TTC的还原强度在拔节期达到最大值,成熟期降到最低,其中,郑麦9023对TTC的还原强度较弱。根中可溶性糖含量在冬前达到最大值,其中,周麦18号的根中可溶性糖含量较高。施磷增加周麦18号和郑麦9023的子粒蛋白质含量,但降低郑麦004的子粒蛋白质含量。     

Potato Cultivar Response to Seasonal Drought Patterns

The ability to minimize potato yield and quality losses due to drought can be greatly improved by understanding the relative responses of different cultivars to seasonal variations in water supply. To address this need, we initiated a 2 year field experiment to determine the responses of the six potato cultivars to different seasonal drought patterns, including 1) full season irrigation at 100 % ET, 2) irrigation at 100 % ET terminated during late bulking , 3) full season irrigation at 70 % ET , 4) irrigation at 70 % ET terminated during late bulking , and 5) a gradual reduction in irrigation from 100 % ET during tuber initiation through early bulking, to 70 % ET during mid-bulking, and 50 % ET through late bulking. GemStar Russet and Ranger Russet, two medium-late maturing cultivars, generally produced the highest yields across the range of drought treatments, but both were fairly sensitive to changes in drought severity. Alturas, a late maturing cultivar, produced relatively high yields with full irrigation, but exhibited the greatest sensitivity to increasing drought severity, particularly when severe late-season water deficits were imposed. Yields for the early maturing cultivar Russet Norkotah were relatively low overall, but it was the least sensitive to changes in drought severity, particularly when late season drought was imposed. Russet Burbank produced comparatively high total yields across the range of drought treatments, but U.S. No. 1 yields were substantially reduced by each seasonal drought pattern. However, it was less sensitive to changes in drought severity than GemStar Russet, Ranger Russet and Alturas. Total and U.S. No. 1 yields for Summit Russet were low for each drought treatment and it exhibited intermediate sensitivity to changes in drought severity. GemStar Russet had the highest water use efficiency based on U.S. No. 1 yield.     

马铃薯抗苏打盐碱性研究离体试验

马铃薯耐盐性的研究大部分集中在NaCl上,极少数进行了抗NaHCO3的研究,本研究利用不同浓度NaHCO3和不同pH的培养基对15个主栽马铃薯品种试管苗进行了25 d胁迫试验,鉴定和筛选抗苏打盐碱性较强的品种。结果表明:盐碱胁迫下各品种生长均受到不同程度抑制。晋薯2号在较重的盐碱处理中成活率比较高,株高、生物产量与对照差异不明显,抗苏打盐碱性强于其它几个品种。。     

大豆品种感染SMV后光合产物的积累和分配

大豆品种感染ＳＭＶ后，感病植株各生育阶段叶片叶绿素含量，光合速率，单株可溶性总糖含量明显低于健株，表明光合产物累积较少，分配到各器官亦少，使干物质和日积累速度除人工，导致表现生物产量下降。     

花生品种幼苗耐低温鉴定的生理生化指标筛选

为鉴定筛选耐低温花生品种,建立花生耐低温评价方法,构建花生耐低温综合数学评价模型,以11个花 生品种为材料,5℃低温胁迫72 h,通过测定胁迫前后花生幼苗叶绿素（SPAD）、叶绿素荧光参数、光合参数、相对电 导率、超氧化物歧化酶活性、过氧化物酶活性、过氧化氢酶活性、丙二醛含量以及可溶性蛋白含量等15个生理生化 指标,利用各单项指标的耐低温系数作为评价依据,运用主成分分析法、隶属函数分析法以及聚类分析法进行花生 耐低温综合评价,并利用逐步回归法筛选与花生耐低温关系密切的生理指标。本实验利用主成分分析法有5个主 成分入选,可将15个单项生理生化指标转换为5个互相独立的综合指标,通过隶属函数法和聚类分析法将11个花 生品种划分为：耐低温型（山花8号、吉花1954Z和吉花1955Z）、中间型（吉花1953Z、狮头企、冀油6、粤油92和中花 8）及敏感型（伏花生、开农53和吉花11）3类;利用逐步回归方程建立花生幼苗耐低温评价数学模型,精度大于 99.00%,筛选出净光合速率、实际光化学效率、最大光化学效率、光化学淬灭系数、可溶性蛋白、过氧化物酶和过氧 化氢酶7个耐低温鉴定指标。耐低温的花生品种（系）低温胁迫后,反应中心的开放程度较大,光系统受到的伤害较 低,能维持较高的净光合速率,能更好地清除花生体内细胞的活性氧和自由基类物质,膜脂质过氧化损伤较低。在 相同低温处理时可以通过测定7个指标对花生品种耐低温能力进行快速鉴定和预测,为东北花生耐低温品种选育 及大规模品种耐低温评价奠定基础。     

外源水杨酸对盐胁迫下巴西蕉生理的影响

香蕉是世界进出口贸易中具有重要经济价值的水果,也是非洲国家的粮食作物。盐害是影响香蕉产量和品质的重要因子之一。巴西蕉是我国华南地区的主栽品种。水杨酸在植物生理和代谢中扮演重要角色。盐胁迫下,外源水杨酸处理巴西蕉（Musa AAA Cavendish var. Brazil）幼苗的生理指标的变化未见报道。本研究通过叶面喷施0、0.5、1.0、2.0 mmol/L外源水杨酸,测定70 mmol/L NaCl胁迫下的巴西蕉幼苗叶片相对含水量、叶绿素含量、脯氨酸含量等生理指标的变化。结果表明,盐胁迫下巴西蕉幼苗的叶片相对含水量和叶绿素含量与对照相比显著下降,而脯氨酸含量、可溶性糖含量、可溶性蛋白含量以及丙二醛含量与对照相比均显著上升。施加0.5、1.0 mmol/L水杨酸处理与盐胁迫相比提高叶片相对含水量和叶绿素含量,提高叶片脯氨酸、可溶性糖和可溶性蛋白的含量,并且降低叶片丙二醛含量,而2.0 mmol/L 水杨酸处理的叶片相对含水量、脯氨酸含量、可溶性糖和可溶性蛋白含量与盐胁迫处理的差异不显著。因此,施加较低浓度的水杨酸（0.5、1.0 mmol/L）可在一定程度上缓解盐胁迫现象,但是高浓度水杨酸（2.0 mmol/L）缓解效果不明显,其中以1.0 mmol/L水杨酸处理效果最好。     

不同钼积累水平大豆品种苗期碳氮代谢生理差异

      为探究不同钼积累能力的大豆品种对缺钼条件下生理代谢的差异,以品种1301（钼高积累）和品种1304（钼低积累）为材料,在营养液培养下研究了两个品种光合碳代谢以及氮代谢生理差异。结果表明：缺钼降低了大豆叶片光合碳代谢能力。缺钼条件下,品种1301叶片光合速率可溶性糖、叶绿素a、叶绿素b以及叶绿素a+b 含量显著高于1304,表明1301具有较高的光合碳代谢能力。缺钼也降低了根中氮代谢能力。缺钼条件下,品种1301中硝酸还原酶活性和铵态氮含量均显著高于品种1304,表明1301具有较强的氮代谢能力。以上结果表明大豆钼高积累品种能累积较多的钼,且表现出较高的碳氮代谢能力。因此认为培育大豆钼高积累品种是提高大豆生理代谢能力的一种经济有效的措施。     

Mixed cropping with ice plant alleviates the damage and the growth of cowpea under consecutive NaCl treatment and after the recovery from high salinity

We investigated the alleviative effects of mixed cropping using ice plant, which is one of the salt-accumulating halophytes, on the damage and growth inhibition of cowpea, which is not tolerant to high salinity. Three cropping patterns (mono cropping of cowpea and ice plant and their combination) were tested. The plants were treated with 0, 100, 200 and 300 mM NaCl for 14 days (consecutive NaCl). The plants were also treated with NaCl for 3 days, followed by 2 weeks (short-term recovery) and 1 month (long-term recovery) recovery. Salinity levels for short-term recovery were similar to those of the consecutive experiment, while the concentration of long-term recovery was 250 mM. The alleviative effects of mixed cropping in the consecutive NaCl experiment were observed at 200 and 300 mM NaCl. Mixed cropping significantly reduced the Na content in the cowpea leaves at 200 and 300 mM NaCl compared with mono cropping. In addition, the Na content in the soil of mix-cropped cowpea at 200 and 300 mM NaCl was statistically lower than that of the mono cropping. Mixed cropping was effective to recover from high concentration of NaCl in the experiments of short- and long-term recovery. These results indicate that mixed cropping with a halophyte could be effective in mitigating the damage and growth inhibition of a glycophyte not only under salinity but also under recovery periods.