硼对油菜不同品种酶活性和根系活力的影响

在土培和水培条件下,研究硼对不同芥菜型油菜品种某些酶活性和根系参数的差异。结果表明,缺硼使叶片中SOD、CAT活性降低,而使POD和G6PDHase增加;敏感品种的缺硼与否差异显著,而不敏感品种则差异不明显。缺硼对敏感品种根系长度、重量、体积、表面积、活跃吸收面积以及比活跃表面积的抑制作用也明显大于不敏感品种,因而影响养分的吸收和代谢。     

硼对不同硼效率棉花品种苗期叶片膜脂过氧化和多胺含量的影响

土培条件下研究缺硼对不同硼效率棉花品种苗期叶片膜伤害、保护酶活性及多胺化合物含量的影响。结果表明 ,遭受缺硼胁迫时 ,两棉花品种叶片膜透性和丙二醛含量增加 ,膜脂肪酸不饱和度下降 ,保护酶SOD、POD、CAT活性降低 ,但硼高效品种变化幅度比低效品种小。缺硼还导致两品种叶片中腐胺 (Put)含量显著降低 ,而低效品种降低幅度更大 ,但缺硼使高效品种叶片中精胺 (Spm)、亚精胺 (Spd)含量及多胺总量 (Spd +Spm +Put)显著升高 ,低效品种仅有升高趋势。推测硼高效品种在缺硼条件下保持较高的多胺含量是其保护酶活性较高、膜受伤害程度较轻的原因之一。     

不同硼效率棉花品种木质部和韧皮部汁液中矿质养分的差异

溶液培养条件下研究硼对2个硼效率不同的棉花品种木质部、韧皮部中硼及其它矿质养分运输的影响。结果表明,缺硼使2个棉花品种木质部汁液硼含量及溢出量明显降低,低效品种降低幅度大于高效品种。供硼充足(0.5mg/L)时,2个棉花品种木质部汁液中硼浓度均小于培养液中硼浓度;缺硼(0.002mg/L)时,高效品种与低效品种木质部汁液硼浓度分别是培养液硼浓度的32.0和20.5倍。缺硼使2个棉花品种木质部汁液中钾、锰、铜、锌含量均升高,高效品种升高幅度较大;钙含量均降低,低效品种降低幅度较大;高效品种镁含量增高,低效品种降低。而2个棉花品种木质部各养分(钾、镁、钙、锰、铜、锌)溢出量均降低,低效品种降低更明显。无论在缺硼或供硼充足时,2个棉花品种韧皮部中硼浓度均极低,但韧皮部溢泌液中其它养分受缺硼影响品种间表现不同,高效品种韧皮部钾、镁、锰、铜溢出量升高,低效品种则降低;2个品种钙、锌溢出量均降低,低效品种降低幅度更大。     

不同硼效率棉花品种果胶与不同形态硼含量的差异

溶液培养条件下研究硼(B)对不同B效率棉花品种水溶性果胶、原果胶及水溶性B、酸溶性B含量的影响.结果表明,供B充足时,B低效棉花品种各部位果胶含量均大于高效品种,不同形态B含量也有同样的规律.缺B时,高效品种各部位果胶含量一般高于低效品种.严重缺B使2个棉花品种不同形态B含量均显著降低,水溶性B变化比酸溶性B更明显,低效品种各部位酸溶性B及上部幼叶水溶性B含量降低幅度均大于高效品种,下部老叶和根中水溶性B降低幅度小于高效品种.缺B还使2个品种上部幼叶与下部老叶水溶性B含量比值增加,高效品种增加幅度大于低效品种,该比值在品种间的差异明显大于水溶性B和酸溶性B含量的差异,可以更好地反映不同品种的B效率.     

硼对不同甘蓝型油菜品种细胞壁酶活性的影响

在溶液培养条件下,选用甘蓝型油菜硼高效和硼低效品种,研究硼对细胞壁酶活性的影响。结果表明,不同生育期缺硼均使油菜根系细胞壁过氧化物酶(POD) 活性显著升高;上部叶片细胞壁POD 活性显著下降;下部叶片处理间的差异不显著,但同一生育期细胞壁POD 活性硼高效品种显著高于硼低效品种。油菜根系细胞壁IAA 氧化酶活性,缺硼时两品种薹期和花期显著升高,苗期差异不显著;上部叶片细胞壁IAA 氧化酶活性缺硼时显著降低,硼高效品种花期差异不显著;缺硼对下部叶片细胞壁IAA 氧化酶活性影响不大,但低效品种花期该酶活性显著降低。     

不同水、氮条件对水稻苗生长及伤流液的影响

为探明不同水分供应和氮素形态对水稻根苗及伤流液的影响,设正常水分及50 g/L PEG模拟水分胁迫和3种不同质量比例的NH4+-N/NO3--N（9/1,5/5,1/9）氮素营养处理,测定了水稻幼苗生物量,根系形态指标,根系活力及根基伤流量。结果表明,正常水分条件下,NH4+-N促进水稻根系平均直径增大,有利于水稻地上部物质累积;NO3--N则使水稻根系总吸收面积增大,促进根系物质累积;NH4+-N/NO3--N为5/5处理的水稻活跃吸收面积最大,活跃吸收面积比亦最高。水分胁迫条件下,NH4+-N/NO3--N为5/5的处理更有利于水稻地上部分的生长,NO3--N有利于水稻鲜重和干重增加,促进根系平均直径增大,水稻的根系总吸收面积、活跃吸收面积均随NO3--N供应比例的增加呈上升趋势。正常水分条件下,水稻幼苗白天的耗水量随NH4+-N/ NO3--N比例降低呈下降趋势,水分胁迫条件降低了水稻对水分的吸收。水分胁迫显著降低各处理水稻伤流量,正常水分条件下,NH4+-N/NO3--N为5/5处理的水稻伤流量最大;水分胁迫后,9/1处理的水稻伤流量相对较多。     

不同磷营养油菜品种根系形态及生理特性差异研究

研究不同磷营养油菜对磷素的反应及其根系形态特征、生理特性等方面的差异,结果表明:磷高效油菜需磷量较小,而在缺磷时吸磷量较大;缺磷时两种油菜品种根冠比增加,且磷高效品种增加幅度大于磷低效品种;缺磷时,磷高效品种具有较长的根系,较大的根体积、根表面积与根活跃吸收表面积,而加磷时,两品种差异不大。油菜缺磷时,磷高效品种磷外渗率小于磷低效品种,加磷时两品种磷外渗率差异不大。缺磷时磷高效品种对磷的亲和力大于磷低效品种,加磷时磷高效品种中磷进入根系的最大净流量小于磷低效品种。     

甘蓝型油菜不同磷效率品种根系形态及生理特性的研究

对甘蓝型油菜磷高效品种B56和磷低效品种B10苗期根系生长状况、根系磷吸收动力学参数和根系分泌酸性磷酸酶特性进行了比较研究。结果表明,在两种供磷条件下,B56的吸磷量均显著高于B10,磷高效品种与磷低效品种相比,B56具有较大的根干重、根长、根表面积和侧根数量。缺磷胁迫条件下,B56的根系磷吸收动力学参数Km显著低于B10;而在正常供磷条件下,两个品种的最大吸收速率Im ax和Km没有显著差异。缺磷条件下,B56的根系分泌酸性磷酸酶活性显著高于B10。     

不同水稻基因型的根系形态生理特性与高效氮素吸收

土培盆栽试验下，采用3个氮素吸收效率（NAE）有显著差异的水稻基因型五优244（低NAE）、R83—12（中NAE）和水源349（高NAE）为材料，研究了水稻拔节期根系形态特征和生理特性的基因型差异及其与高效氮索吸收的关系。结果表明，水源349总根长、根密度、根表面积和根干重极显著高于R83．12和五优244，且根系总吸收面积、活跃吸收面积和活跃吸收面积／总吸收面积最大，为高效氮索吸收提供了条件。水源349具有较强的根系耗能、氧化还原力、硝酸还原酶、谷氨酰胺合成酶、谷氨酸合酶和谷氨酸脱氢酶活性，促进根内碳水化合物的合成及氮吸收和同化，提高了根系伤流强度及可溶性糖和游离氨基酸含量，进而显著提高了地上部氮含量和氮积累量。逐步回归表明，拔节期较高的根密度、根系总吸收面积和地上部氮含量是水稻氮索高效吸收的重要特征，可作为水稻氮素高效管理和遗传改良的可靠指标。     

砂培条件下两种磷效率棉花根系形态及根际特征差异

为对比两种磷效率棉花在两种磷水平(0.1和5 mmol/L)的根系形态和根际特征的差异。以磷高效型棉花ZM42和磷低效型棉花XLZ13为研究对象设计砂培花盆分层试验,测定生物量、吸磷量、根系形态数据、分层Olsen－P、 pH值和酸性磷酸酶。结果表明：在砂培条件下两种磷效率棉花生物量和磷素积累量随施磷量的增加均有不同程度增加; ZM42在两种磷处理的根部生物量、吸磷量以及根冠比都优于XLZ13。在两种磷处理下, ZM42根系中根径(0~0.4 mm)的细根长度较XLZ13长,细根在总根长中的比例较高。总根长中细根越多有利于促进植株对磷的吸收。生长介质中磷含量降低时,棉花根际pH值也随之降低,高效品种ZM42的根际pH值降低幅度显著高于XLZ13;两种磷效率棉花在两个时期的根际土壤磷酸酶活性均随着施磷量的减少而增加,磷高效棉花ZM42分泌的土壤磷酸酶活性均高于磷低效棉花XLZ13。由此可见,两种磷效率棉花在相同生长介质中根际机理存在差异,且在低磷胁迫下磷高效棉花根系形态特征改变是根际磷活化主要机理之一。     

不同硼效率甘蓝型油菜苗期对硼镁营养的反应

利用溶液培养研究硼低效和高效甘蓝型油菜(Brassica.napus)苗期对硼镁营养的反应。结果表明,低硼浓度下提高镁时,油菜的生长受影响不大,硼含量和累积量降低,镁含量和累积量及叶绿素上升。低镁浓度下提高硼时,油菜镁含量、镁积累量降低,且硼低效品种降低幅度大于硼高效;叶绿素降低幅度则硼高效大于硼低效品种。高硼浓度下提高镁时,硼镁含量和累积量及叶绿素含量均提高,提高幅度为硼高效品种大于低效品种。高镁浓度下提高硼时,硼镁表现出显著的相互促进,硼高效品种促进效应大于低效品种。在很大程度上镁影响油菜叶绿素a的含量,而硼影响油菜叶绿素b的含量。硼镁营养对锌含量无大的影响;在低镁浓度下,油菜低效品种锰含量显著增加。无论是低镁或高镁浓度下提高硼,硼高效和低效品种铁含量均有所增加,低效品种增加显著。     

Physiological and genetic responses to boron deficiency in Brassica napus: A review

Abstract

Boron (B) is an essential microelement for the growth and development of plants, and B deficiency affects many biochemical and physiological processes. Brassica napus L. has a high demand for B and is extremely sensitive to B deficiency. Seed yields and oil quality of B. napus are often limited by the low availability of B in soils. Developing new cultivars of B. napus with high B efficiency is therefore required, which requires a greater understanding of responses to B deficiency. Significant genotypic differences in response to low soil B have been observed among varieties of B. napus. B-efficient genotypes can grow and yield normally and usually have a larger root system than B-inefficient genotypes at low B conditions. The mechanisms for B efficiency in B. napus are attributed to B absorption, transportation and utilization. In addition, the cell wall component plays an important role in the tolerance of B. napus to B deficiency, and the B-efficient line presents fewer B-binding sites in the cell walls compared with the B-inefficient line. Genetic and proteomic analyses in B. napus revealed the modulation of a complex network in response to B deficiency. This review gives a comparative overview of the physiological and genetic responses to B deficiency in B. napus and discusses the possible underlying mechanisms of B efficiency.     

对缺硼反应不同的油菜品种根系生长特性研究

在营养液培养、根箱土培和组织培养条件下 ,研究了不同油菜品种根系生长变化动态。结果表明 ,缺硼明显降低根系长度 ,尤其抑制根尖伸长 ,且与品种间缺硼敏感性密切相关 ,即对敏感品种的抑制程度高于不敏感品种。营养液培养条件下缺硼 5天 ,敏感品种根系生长严重受阻 ,根尖解剖结构破坏 ,根冠脱落 ,根尖膨大 ,细胞畸形且排列紊乱 ;而不敏感品种受害程度相对较轻 ,根冠完整 ,根尖稍膨大。表明油菜缺硼基因型差异首先表现在根尖形成和伸长生长上     

油菜硼高效的遗传

Field experiments were conducted to study the inheritance of boron efficiency in oilseed rape (Brassica napus L.) by evaluating the boron (B) efficiency coefficient (BEC, the ratio of the seed yield at below the critical boron level to that at the boron-sufficient level) with 657 F_2:3 lines of a population derived from a cross between a B-efficient cultivar, Qingyou 10, and a B-inefficient cultivar, Bakow. Qingyou 10 had high BEC as well as high seed yield at low available soil B. On the contrary, Bakow produced low seed yield at low B status. Boron deficiency decreased the seed yield of the F_2:3 lines to different extents and the distribution of BEC of the population showed a bimodal pattern. When the 657 F_2:3 lines were grouped into B-efficient lines and B-inefficient lines according to their BEC, the ratio of B-efficient lines to B-inefficient lines fitted the expected ratio (3:1), indicating that one major gene controlled the B-efficiency trait. 127 F_2:3 lines selected from the population at random, with distribution of BEC similar to that of the overall population, were used to identify the target region for fine mapping of the boron efficiency gene.     

不同铁效率玉米品种苗期适应低铁胁迫的根系特征与铁积累差异

  【目的】  石灰性土壤高pH和高重碳酸盐含量严重影响土壤中有效铁含量,导致作物缺铁黄化、减产,铁高效玉米品种的推广应用是实现石灰性土壤玉米高产稳产的重要途径。 本研究探讨不同铁效率玉米品种适应低铁胁迫的根系特征与铁积累差异,旨在为铁高效玉米品种的推广应用提供科学依据。  【方法】  试验以铁高效玉米品种正红2号 (ZH2)、正大619 (ZD619) 和铁低效玉米品种川单418 (CD418)、先玉508 (XY508) 为材料,设置极低铁处理 (Fe0,Fe浓度为0 μmol/L)、低铁处理 (Fe10,Fe浓度为10 μmol/L) 和正常供铁 (Fe100,Fe浓度为100 μmol/L) 3个处理,通过砂培试验,研究不同铁效率玉米品种适应低铁胁迫的根系形态特征、干物质重、铁积累及铁吸收利用差异。  【结果】  低铁胁迫下,玉米幼苗的根干重、单株干重、铁积累量、根系相对铁吸收效率均显著降低,而根冠比与铁素生理效率均显著升高,且随胁迫程度的增加变幅加大;总根长、根表面积、根体积和根直径则表现出明显的品种差异,与正常铁处理 (Fe100)相比,低铁处理下铁低效品种的总根长、根表面积和根体积显著降低,根直径显著增加,而铁高效品种的总根长和根表面积差异不显著,根体积显著增加,根直径在极低铁处理(Fe0)下显著降低,低铁处理 (Fe10)下差异不显著;铁高效品种总根长、根表面积、根体积、根干重、单株干物重、铁积累量和根系铁吸收效率的降幅及根冠比的增幅均明显低于铁低效品种,而铁生理效率的增幅高于铁低效品种。相关性分析结果表明,玉米幼苗铁积累量与总根长、根表面积、根体积和根干重均呈显著正相关,而与根冠比呈负相关,其中与总根长 (R2 = 0.8546) 和根表面积 (R2 = 0.8983) 相关性最强。  【结论】  与铁低效玉米品种相比,铁高效玉米品种低铁胁迫下具有较优的总根长、根表面积及较高的根系铁吸收效率与铁生理效率,促进了其对铁的高效吸收与利用,提高了其对低铁环境的适应能力。     

不同氮形态对两种基因型水稻根系形态及氮吸收效率的影响

为了探索不同铵硝配比对水稻根系形态和地上部N累积量的影响及其与根系吸N量的关系,以苗期N高效品种桂单4号和N低效品种南光为材料,设置1.0mmol/L NO3--N、0.5mmol/L NH4NO3、1.0mmol/L NH4 -N 3个N处理开展了研究.结果表明:含有NO3--N的处理总根长、总根数和总根表面积均明显高于NH4 -N的处理,且桂单4号和南光两种基因型水稻之间存在差异.两品种均在0.5 mmol/L NH4NO3处理中根系吸N量最高,其次是1.0 mmol/L NH4 -N处理,1.0 mmol/L NO3--N的处理根系吸N量最少.     

Abstracts of nippon Dozyohiryogaku Zasshi

Aluminum toxicity and boron deficiency are the major factors that limit plant growth and development in acid soils and in B-deficient soils. Root growth inhibition is an early symptom of AI toxicity and B deficiency. Effects of AI and B supply and their interaction on the growth of wheat (Triticum aestivum L.) seedlings were investigated using hydroponics. Fifteen wheat cultivars commonly grown in Bangladesh were used and found to differ considerably in their tolerance to AI toxicity and B deficiency. The relative root length of all the wheat cultivars at 50 µM AI (pH 4.5) ranged from 27 to 71% relative to the control (0 µM AI). Among the cultivars, Inia66 and Kalyansona were found to be the most Al-tolerant and sensitive cultivars, respectively, based on the data of relative root length, malate exudation and AI content of roots. Malate was detected in all the cultivars in the presence of 100 µM AI (pH 4.3). Inia66 exuded a 6-fold larger amount of malate and the AI content of roots was 4 times lower than that in Kalyansona. The vigorous seedling growth was observed at 40 µM B among the series of B treatments. Considerable cultivar differences in response to 40 µM B were observed among the 15 cultivars. Kalyansona was considered to be the most sensitive and Kheri the most tolerant to B deficiency. The interaction effects of B ( 40 and 200 µM) and AI (50 µM) on seedling growth were also examined in Inia66 and Kalyansona. Root growth was inhibited in the presence of Al but B supply especially at 200 µM B in the Kalyansona cultivar caused a slight improvement.     

Root growth,nutrient uptake and yield of soybean cultivars grown in the field

Abstract

Soybean (Glycine max L. Merr.) cultivars differ in their root morphology and their nutrient uptake capabilities. The relation between root growth, P and K uptake, and grain yield was investigated using eight cultivars grown in the field on Raub (Aquic Argiudoll) silt loam which received 49 kg P/ha and 93 kg K/ha. Hobbit (maturity group III, determinate) was among the highest in grain yield, P and K uptakes, and root system length. However, this cultivar was intermediate in its relative efficiency to utilize P and K to produce grain yield; among the most efficient cultivars were Asgrow 3127 (maturity group II) and Williams‐79 (maturity group III). The hay cultivar, Wilson‐6, was the least efficient. It was concluded that even though grain yield was correlated with nutrient uptake, selection for higher yields was not necessarily a selection for higher efficiency in utilization of fertilizer for grain production.