土壤水分和供硼状况对不同硼效率油菜苗期生长、水分含量和硼形态的影响

通过土培试验,研究了土壤水分和供硼状况对不同硼效率油菜苗期生长、叶片水分含量和硼形态的影响.结果表明:低水分胁迫条件下,硼高效甘蓝品种和硼低效甘蓝品种在高供硼水平下的单株鲜质量比低供硼水平分别增加了43.1%和31.7%,但品种间没有显著差异;硼高效品种在两种供硼水平下的束缚态水分含量分别比低效品种高11.4%和1.7%,半束缚态硼分配比例分别比低效品种高6.9%和23.8%.正常水分条件下,硼高效甘蓝品种和硼低效甘蓝品种在高供硼水平下的单株鲜质量比低供硼水平分别增加了11.1%和27.4%;硼高效品种在两种供硼水平下的自由态水分含量较硼低效品种多,自由态硼累积量为低效品种的2倍多,这有利于硼在高效植物体内的移动运输.     

不同甘蓝型油菜及其F1硼效率差异与单糖的关系

在硼高效甘蓝型油菜品种及杂交种中 ,单糖的种类比低效品种多 ;除果糖外 ,其绝对含量也远高于低效品种。果糖和甘露糖能与硼反应形成硼糖络合物 ,在硼高效品种及其杂交种中 ,甘露糖的相对含量和绝对含量都高于低效品种 ,尽管在低效品种和杂交种中果糖的含量比高效品种高 ,但果糖含量低 ,起主导作用的仍是甘露糖 ,这种差别很可能是导致硼效率差异的原因之一。     

重庆三峡库区柑橘硼营养状况及其影响因子

为了解重庆三峡库区柑橘叶片硼营养状况及其影响因子,在该区域12个主产县(区)的代表性果园采集叶片样品954份和土壤样品302份,测定叶片硼含量,并分析了土壤有效硼、土壤pH值、品种、砧木和树龄对叶片硼营养的影响.结果表明: 该区域柑橘叶片硼含量不足(<35 mg·kg^-1)的果园比例达41.6%,土壤有效硼含量不足(<0.5 mg·kg^-1)的果园比例高达89.4%,柑橘叶片硼含量与土壤有效硼含量的相关性未达显著水平.土壤pH值、品种、砧木和树龄均影响叶片硼含量.pH值4.5～6.4土壤上的柑橘叶片硼含量显著高于pH值6.5～8.5土壤上的柑橘;品种间叶片硼含量为:温州蜜柑>柚类>夏橙>普通甜橙>杂柑>脐橙;枳砧和酸柚砧柑橘叶片硼含量显著高于枳橙砧和红橘砧柑橘;3～8年生柑橘树叶片硼含量适宜(35～100 mg·kg^-1)样品比例比8年生以上柑橘树高6.6%.     

不同磷效率小麦品种对缺磷胁迫反应的比较

在营养液培养条件下,以根据相对产量为指标筛选出的6个不同磷效率的小麦(Triticum aestivum L.)品种为材料,对其苗期在缺磷条件下生长、根冠磷含量及其分配,以及叶片韧皮部汁液中磷浓度等进行了比较研究。结果表明,缺磷抑制植株地上部生长,但刺激根系生长,导致植株根／冠比增加。无论在供磷或缺磷条件下,磷高效品种的根冠生长速率都低于磷低效品种。缺磷导致植株体内的磷含量下降与根系相比,地上部磷含量的下降速率更快。但在缺磷条件下,不同磷效率的小麦品种根冠间的磷分配变化没有差异。研究发现,在正常供磷条件下,磷高效小麦品种的叶片韧皮部汁液中磷浓度较低,而磷低效品种的叶片韧皮部汁液中磷浓度较高。但开始缺磷后,磷高效品种的叶片韧皮部汁液中的磷浓度下降较慢,使其相对磷浓度较高。缺磷后10天,磷低效品种叶片韧皮部汁液中的磷浓度为供磷对照的35．9％,而磷高效品种叶片韧皮部汁液中的磷浓度为供磷对照的59％。     

不同磷效率小麦品种对缺磷胁迫反应的比较

在营养液培养条件下,以根据相对产量为指标筛选出的6个不同磷效率的小麦(Triticum aestivum L.)品种为材料,对其苗期在缺磷条件下生长、根冠磷含量及其分配,以及叶片韧皮部汁液中磷浓度等进行了比较研究.结果表明,缺磷抑制植株地上部生长,但刺激根系生长,导致植株根/冠比增加.无论在供磷或缺磷条件下,磷高效品种的根冠生长速率都低于磷低效品种.缺磷导致植株体内的磷含量下降与根系相比,地上部磷含量的下降速率更快.但在缺磷条件下,不同磷效率的小麦品种根冠间的磷分配变化没有差异.研究发现,在正常供磷条件下,磷高效小麦品种的叶片韧皮部汁液中磷浓度较低,而磷低效品种的叶片韧皮部汁液中磷浓度较高.但开始缺磷后,磷高效品种的叶片韧皮部汁液中的磷浓度下降较慢,使其相对磷浓度较高.缺磷后1 0天,磷低效品种叶片韧皮部汁液中的磷浓度为供磷对照的35.9%,而磷高效品种叶片韧皮部汁液中的磷浓度为供磷对照的59%.     

甘蓝型油菜扩展蛋白家族的全基因组鉴定及其对缺硼胁迫响应的差异分析

以甘蓝型油菜(Brassica napus L.)硼高效品种‘青油10号’和硼低效品种‘Westar 10’为研究对象,采用生物信息学分析、转录组测序和实时荧光定量PCR技术,鉴定其基因组中扩展蛋白的家族成员,并对该基因家族响应缺硼胁迫的表达差异进行分析。结果显示,甘蓝型油菜基因组中包含109个扩展蛋白,可分为4个亚家族,包括:79个扩展蛋白A(BnaEXPAs)、21个扩展蛋白B(BnaEXPBs)、5个类扩展蛋白A(BnaEXLAs)和4个类扩展蛋白B(BnaEXLBs)。同一亚家族中的扩展蛋白具有相对保守的基因结构和蛋白质基序组成。这些扩展蛋白基因分布在19条染色体上,其中10个位于硼高效QTL区间内。转录组测序分析结果表明,缺硼胁迫时‘青油10号’的根、幼叶和老叶中分别有40、18和30个扩展蛋白基因显著上调或下调表达;而‘Westar10’中分别有27、24和41个扩展蛋白基因显著上调或下调表达。其中‘青油10号’根中的BnaC04.EXPA6a,幼叶中的BnaA09.EXPA5以及老叶中的BnaA09.EXPA16、BnaC04.EXPA3、BnaCnn.EXPA5b和BnaA03.EXPA8基因的表达水平均显著高于‘Westar10’。研究结果说明甘蓝型油菜基因组中扩展蛋白基因家族数量庞大,其中高、低效品种间和不同硼水平中差异表达的扩展蛋白可能在甘蓝型油菜低硼适应性中发挥重要作用。     

缺硼对棉花 黄瓜和油菜乙烯释放的影响

本试验通过水培和土培试验的方法,研究了缺硼对棉花、油菜和黄瓜乙烯释放的影响。结果表明：缺硼条件下,棉花、黄瓜乙烯释放量显著增加,而油菜无论缺硼和正常硼条件下,乙烯释放量较低且没有明显差异,乙烯释放量的增加对棉花和黄瓜的生长发育有抑制作用;喷施乙烯合成抑制剂和乙烯生理效应抑制剂在一定程度上能减轻棉花和黄瓜的缺硼症状。黄瓜水培结果表明：在黄瓜缺硼症状出现前,乙烯释放量没有明显增加,随着缺硼时间的延长,缺硼症状的出现,乙烯释放量显著增加,因而乙烯释放量的增加不是缺硼导致黄瓜生理失调的直接反应。     

缺硼对棉花、黄瓜和油菜乙烯释放的影响

本试验通过水培和土培试验的方法,研究了缺硼对棉花、油菜和黄瓜乙烯释放的影响。结果表明：缺硼条件下,棉花、黄瓜乙烯释放量显著增加,而油菜无论缺硼和正常硼条件下,乙烯释放量较低且没有明显差异,乙烯释放量的增加对棉花和黄瓜的生长发育有抑制作用;喷施乙烯合成抑制剂和乙烯生理效应抑制剂在一定程度上能减轻棉花和黄瓜的缺硼症状。黄瓜水培结果表明：在黄瓜缺硼症状出现前,乙烯释放量没有明显增加,随着缺硼时间的延长,缺硼症状的出现,乙烯释放量显著增加,因而乙烯释放量的增加不是缺硼导致黄瓜生理失调的直接反应。     

不同水平硼对棉花体内硼含量及其分布的影响

本试验在盆栽条件下,以灰紫色土为供试土壤,研究不同水平硼(表1)下,棉花(Gossypium hirsutum,品种“鄂沙28”)体内硼含量及其分布规律。结果如下: 1.棉花不同生育期各器官含硼量随土壤有效硼的增加呈直线增加(图1),除铃期根系外,其相关系数均     

硼对油菜体内核酸代谢的影响

硼胁迫造成油菜植株生长异常,使幼苗干物重显著下降;而幼苗叶片和花纲内ＲＮａｓｅ活性产强,ＲＮＡ的分解加剧,ＲＮＡ和ＤＮＡ含量均下降,引起蛋白质的合成受阻,可溶性蛋白质含量急剧减少。这说明缺硼或硼过量时,植物体内核酸分解和加剧是核酸含量下降的一个重要原因。     

Differential response of oilseed rape (Brassica napus L.) cultivars to low boron supply

Three experiments were carried out on an alluvial sandy loam (Udifluvent) at Tonglu, Zhejiang Province, P.R. China from 1992 to 1995, to determine the genotypic range in boron (B) efficiency of 16 oilseed rape (Brassica napus L.) cultivars, to identify the B-efficient cultivars and to identify specific responses which can be utilised for selection in a breeding program. The 16 cultivars which included high-quality and conventional types differed significantly in survival, plant height, leaf area, shoot dry weight and seed yield; however, the ranking of the cultivars for their seed yield or other plant traits differed with B treatment. With severe B deficiency (CaCl2 extractable B < 0.26 mg/kg) and no boron applied, none of the cultivars exhibited significant B efficiency, with seed yield <300 kg/ha. With moderate B deficiency (CaCl2 extractable B 0.34 mg/kg or 0.17 kg B/ha applied), seed yield varied significantly among the cultivars from 397 to 1889 kg/ha in year 1 and from 616 to 1260 kg/ha in year 3. Zhongyou 821 and 92-13 were the most B-efficient and Wanyou 324, Huashuang 2 and Su 2051 were the most B-inefficient cultivars under moderate B deficiency. Significant differences were found among the cultivars in leaf B concentration; however, there was no close relationship between leaf B concentration and seed yield responses to B of oilseed cultivars. Of all the growth parameters measured, leaf area was the early indicator best correlated with subsequent seed yield and may be useful for evaluating the response of cultivars to low B supply. Contrary to current opinion, it was also found that high-quality oilseed rape cultivars were not all sensitive to low B supply nor were all conventional cultivars B-efficient.     

施硼对番木瓜幼龄株硼形态含量及叶片光合作用的影响

探讨根外喷硼与土壤施硼对植株硼形态含量及叶片光合作用的影响。结果表明,两种供硼方式均可增加植株叶片、叶柄及根的硼形态含量及硼总量,其中以叶片水溶态硼、半束缚态硼及硼总量的增加最为显著。植株硼含量增加提高了叶片净光合速率,但硼过量却抑制了叶片光合能力的提升,而硼中毒导致光合能力显著下降。     

不同供硼水平对绿豆植株形态及其叶片生长特征的影响

利用水培以绿豆为材料,研究不同供硼水平对绿豆植株形态和叶片生长特征的影响。结果表明缺硼抑制绿豆生长,但对根的影响较对冠的影响更大,表现在缺硼导致冠根比增大;缺硼明显抑制叶面积;降低特定叶面积（SLA）,这可能是由于缺硼影响细胞伸展的缘故,造成叶片密度增加,缺硼也提高叶片重量比（LWR)并导致叶脉间失绿,说明缺硼叶片可能过量碳水化合物积累,引起叶绿素降解,与适量供硼比较,过量供硼也影响绿豆的生长,但对冠根比没有影响,表明过量供硼对根和冠具有相同的抑制作用,硼中毒导致成熟叶片脱落,从而影响叶面积,但对特定叶面积（SLA）和叶片重量比（LWR）没有影响。     

Boron deficiency increases putrescine levels in tobacco plants

Polyamine concentrations were determined in leaves and roots of tobacco plants (Nicotiana tabacum L.) subjected to a short-term boron deficiency. A decrease in the growth of shoots and, especially, roots was found under this mineral deficiency. Boron deficiency did not lead to a significant decrease in leaf or root ion concentrations when compared to control treatment; however, as expected, leaf boron concentration was lower in boron-deficient plants in comparison to the control. In leaves, the levels of free putrescine and spermidine were similar in both treatments. In roots, a short-term boron deficiency caused an increase in free putrescine. Moreover, boron-deficient plants had higher conjugated polyamine concentration than boron-sufficient plants, which was especially evident for conjugated putrescine in leaves. A possible link between boron and polyamine levels is proposed and discussed.     

不同土壤水分状况下施硼对油菜硼吸收、利用的影响

1　引　　言我国是油菜生产大国 ,也是一个土壤缺Ｂ面积较大的国家 .由于油菜缺Ｂ问题突出 ,施用Ｂ肥已成为提高油菜产量、改善品质的重要措施[2 ,3 ,11] .但是 ,Ｂ肥的施用不但存在成本高、难度大、效率低的问题 ,而且也存在造成环境污染的可能性[9] .研究表明[8,10 ] ,不同油菜品种对缺Ｂ的反应存在基因型差异 ,因此 ,筛选、培育Ｂ营养高效基因型油菜以适应缺Ｂ土壤环境是解决油菜缺Ｂ问题的最有效途径之一 .植物对土壤中Ｂ的吸收、运输及利用因土壤水分状况而异[4 ,5] .研究不同水分条件下尤其是干旱情况下Ｂ素营养对油菜Ｂ营养效率的影…     

Responses of rape genotypes to boron application

Pot and field experiments were conducted to examine the effect of boron on the yield and quality of different rape genotypes and to identify cultivar variation in some physiological responses to boron. B fertiliser can significantly increase the yields of both traditional and high-quality rape. Significant differences in yield response to boron application were found between cultivars. High quality varieties were more sensitive to boron deficiency than a traditional variety. Application of boron increased plant height, net photosynthetic rate, activity of nitrate reductase (NRA) and dry-weight yield, and decreased the contents of erucic acid and glucosinolate in both traditional and high-quality rape varieties. Boron plays a positive role in keeping the stability of the good characteristics of high quality cultivars.     

植物对硼元素的吸收转运机制

硼是植物生长发育所必需的微量元素,但是在世界范围内,土壤中硼含量过高或者过低都会对植物生长产生影响,是农业生产上的主要问题.近来人们对硼的吸收转运机制的研究取得了突破性进展,鉴定了一些硼的转运通道和转运蛋白,例如：NIP5;1、NIP6;1、BOR1和BOR4,并对它们的转运机制有了一些了解.植物在硼缺少的情况下首先通过转运通道NIP5;1把硼吸收到共质体,然后通过转运蛋白BOR1运入中柱;在高硼毒害时,通过转运蛋白BOR4把过多的硼转出植物体,同时在植物中增加糖醇的含量,过表达BOR1或BOR4都能改变植物对硼含量变化的耐受性.因此,对植物中硼吸收转运机制的研究将有利于人们通过生物学手段提高作物对土壤中硼过高或过低的抗性.     

Boron accumulation and partitioning in wheat cultivars with contrasting tolerance to boron deficiency

Two pot experiments at the Plant Environment Laboratory (PEL), Reading, UK investigated sterility, boron (B) accumulation and B partitioning of wheat cultivars grown with limited B in the growing medium. The first experiment evaluated nine cultivars of spring wheat with diverse field responses to low available soil B, supplied with or without 20 μM B. A second experiment examined the response of a susceptible (SW-41) and a tolerant (Fang-60) cultivar to B-deficiency. These cultivars were supplied with either 20 μM B from sowing to flag leaf emergence and no added B thereafter, or 20 μM B from sowing to maturity. When B was not supplied in the nutrient solution, the number of grains ranged from 4 per ear (cv. BL-1135) to 32 per ear (cv. BL-1249) and sterility of competent florets ranged from 39% to 93%. Boron concentration in the flag leaf at anthesis did not differ greatly when the growing medium contained limited B, but differences between cultivars were evident when B was unlimited. Tolerance of B-deficiency was not related to the B concentration in the flag leaf. Some cultivars produced viable pollen and set grains while others failed to do so at similar B concentrations in the flag leaf. The two contrasting cultivars did not differ much in their pattern of B partitioning when B supply was restricted from flag leaf emergence onwards. Similarly, little evidence was found that the tolerant cultivars translocated B from their leaves, roots or stems when the supply in the growing medium was restricted. The proportion of total B partitioned in different organs was the same irrespective of B supply and cultivar. On average, leaves contained 68% of the total B content in the whole plant compared to 16% in the roots, 10% in the ears and only 6% in the stems. Tolerant or susceptible cultivars of wheat could not be distinguished based on the B concentration and B content of the flag leaf. This revised version was published online in June 2006 with corrections to the Cover Date.