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1.
Changes in the content of carbohydrates and in the activity of hydrolytic enzymes were studied in hyacinth bulbs exposed to low temperatures. It was found that the amount of insoluble carbohydrate initially present in the scales and buds of hyacinth bulbs decreased greatly after a prolonged period of low temperature treatment. This decrease was greater in rooted bulbs, held at a low temperature for 63 days in natural conditions, than in unrooted bulbs stored in a refrigerator for the same period. At the same time the levels of soluble mono- and oligosaccharides, and of soluble starch, increased in the scales and buds of chilled bulbs. These changes in sugar level were found to be correlated with changes in the activity of certain hydrolytic enzymes. The activity of these enzymes was higher in rooted bulbs than in those which had not rooted before treatment. The activity of hydrolytic enzymes was found to be considerably higher in the flower buds than in the scales.  相似文献   

2.
Seasonal changes in native auxins, gibberellins and inhibitors in leaves and bark of Shamouti orange trees were studied. In December and February some auxin activity was found in the pH 6.0 ether fraction of leaves. Gibberellins were found mostly in the pH 7.0 water residue, with a peak in December. Large amounts of abscisic acid-like inhibitors were found in the pH 6.0 ether fraction of leaves, and the pH 7.0 water residue contained other inhibitors. Auxin activity in the bark was higher than in leaves, and the amount of inhibiting substances detected in the bark was much lower. Auxins were found in both fractions, whereas gibberellins were found in the pH 7.0 water residue as well as in the pH 3.0 ether fraction.

Ringing the trunks of trees in March promoted the accumulation of growth regulators in the bark near the ring and in the leaves. The main effect of ringing in August was an accumulation of acidic gibberellins above the ring during the first three weeks after ringing.  相似文献   

3.
番茄不同部位中糖含量和相关酶活性的研究   总被引:25,自引:2,他引:25  
 试验将番茄光合产物运转途径上叶片(源) 、运输系统以及果实(库) 区分开, 分别测定其糖的组成和含量以及糖代谢相关酶的活性。结果表明: 番茄光合产物运转途径上从“源”到“库”各部位糖的组成和含量不同。叶肉中果糖的含量最高, 蔗糖的含量最低; 中筋中以果糖和葡萄糖为主; 叶柄维管束中葡萄糖含量最高, 蔗糖含量次之, 果糖含量最低。节间和果柄维管束中主要含有蔗糖。果实维管束以及果实内各部位中则主要含有葡萄糖和果糖, 且两者含量无显著差异, 蔗糖含量很低。萼片中葡萄糖含量最高, 蔗糖含量最低; 果蒂中3种糖含量均较高且无显著差异。番茄叶肉及光合产物运转组织中转化酶活性很低, 而在库器官的非维管组织中转化酶活性较高。果蒂中的蔗糖合成酶( SS) 活性最高, 其次是叶肉和运转组织, 果实内各部位中SS活性较低。在合成蔗糖的器官—叶肉中, 有较高的蔗糖磷酸合成酶( SPS) 活性, 运转组织中的SPS活性较叶肉中降低, 但果柄维管束和果实维管束中则表现出较高SPS活性, 果肉、果胶质胎座及心室隔壁中的SPS活性最低。  相似文献   

4.
有机化梨园不同栽培措施节肢动物多样性比较   总被引:5,自引:0,他引:5  
运用生物多样性指标对北京顺义地区有机化梨园3个不同栽培区节肢动物群落多样性及其动态进行了系统研究。结果表明,在同一园区内,不同栽培区节肢动物群落的丰富度和均匀度在整个生长季中的动态变化较一致,而优势度出现了明显的时序差别。群落个体数稀植区在大部分时间内均高于其它2区。3个区的主要优势害虫及其天敌在发生时间和数量上有一定差异,早春密植区木虱发生数量较大,稀植区中砂潜、金龟子类害虫以及步甲、蜘蛛类天敌数量相对丰富,入秋后稀植区木虱发生量最大,密植区最小。据此,对主要害虫综合防治体系建立提出了讨论意见。  相似文献   

5.
AIM: To evaluate the changes of somatotropin axis in pre-pubertal rats with catch-up growth born small for gestational age (CUG-SGA). METHODS: The SGA rat model was prepared by diet restriction in pregnant rats.Growth hormone (GH) excretion in 24-h urine, serum level of insulin-like growth factor-1 (IGF-1), the expression of IGF-l and insulin-like growth factor-1 receptor (IGF-1R) in the tibial growth plate and the mRNA expression of IGF-1 in liver were measured in infant rats at the end of week 4. RESULTS: The level of 24-h urinary GH excretion in CUG-SGA group were significantly higher than that in the rats of non-catch-up growth born small for gestational age (NCUG-SGA) group and appropriate for gestational age (AGA) group (both P<0.01). The serum level of IGF-1 and the mRNA expression of IGF-1 in liver in CUG-SGA group were similar to those in AGA group, but significantly higher than those in NCUG-SGA group. The thickness of the tibial growth plate in NCUG-SGA group was significantly lower than that in CUG-SGA group and AGA group. No difference of the growth plate thickness between CUG-SGA group and AGA group was observed, but the thickness of hypertrophy zone of the growth plate in CUG-SGA group were significantly higher than that in NCUG-SGA group and AGA group (both P<0.01). The expression of IGF-1 in the growth plate in CUG-SGA group was similar to that in AGA group but significantly higher than that in NCUG-SGA group (P<0.01). No difference of the IGF-1R expression in the growth plate among these 3 groups was found (P>0.05). CONCLUSION: GH/IGF-1 resistance exists in SGA rats with and without catch-up growth.  相似文献   

6.
树盘铺反光膜降低枇杷果实酸度   总被引:9,自引:0,他引:9  
陈发兴  刘星辉  吴德宜  陈立松 《园艺学报》2010,37(11):1836-1842
以15年生‘解放钟’枇杷为材料,研究了树盘铺反光膜对枇杷果实生长发育过程中果肉可滴定酸(TA)、有机酸含量与酸代谢酶活性及成熟果肉可溶性固形物(TSS)含量的影响。铺反光膜处理可显著提高成熟果肉TSS含量,降低TA。铺反光膜处理,在果实发育前期果肉TA和苹果酸含量比对照上升快,且高于对照;在果实发育后期比对照下降快,成熟果肉均比对照低。苹果酸是决定成熟果肉酸度的主要有机酸,铺反光膜处理下成熟枇杷果肉酸度下降主要是苹果酸含量下降所致。在果实发育前期,铺反光膜处理果肉磷酸烯醇式丙酮酸羧化酶(PEPC)和NAD–苹果酸脱氢酶(NAD-MDH)活性增加的速度和NADP–苹果酸酶(NADP-ME)活性下降的速度均比对照快,处理果肉有较高的PEPC和NAD-MDH活性及较低的NADP-ME活性;在果实发育后期,处理果肉的PEPC和NAD-MDH活性下降的速度及NADP-ME上升的速度均比对照快,处理果肉有较低的PEPC和NAD-MDH活性及较高的NADP- ME活性。铺反光膜处理下成熟果肉苹果酸含量下降可能是苹果酸合成减少和降解增加所致。  相似文献   

7.
鸭梨秋施^15N尿素的吸收与分配   总被引:32,自引:2,他引:30  
徐季娥  陈良 《园艺学报》1993,20(2):145-149
  相似文献   

8.
生长季苹果硼素营养变化动态及诊断   总被引:4,自引:0,他引:4  
田间条件下,玫瑰红/平邑甜茶新生器官全硼变化动态表现不同:短梢叶全硼含量较稳定;长梢叶及其皮部变化动态相似,生长季早期全硼下降,中期升高,后期又下降;果实全硼变化最大,随果实膨大,全硼持续降低,其中以花后一个月降低幅度最大。缺硼植株的果实及长梢皮部全硼显著降低,其它部位全硼含量与缺硼症表现程度之间不一致。果实采收后,长梢皮部全硼含量与次年幼果的全硼含量呈显著正相关。秋季干旱处理长梢皮部全硼含量下降幅度大于叶片和果实。长梢皮部可作为苹果硼素营养的诊断器官。  相似文献   

9.
钙在橄榄树器官中的定量研究   总被引:3,自引:0,他引:3  
本研究用原子吸收光谱法分析了果园土壤及橄榄树体各器官中钙量和不同组分钙的含量。结果表明:0~30cm土层中钙含量最高为0.65mg/g。橄榄器官中叶的钙含量最高为4.523mg/g,其次为根、果、结果枝。地上部器官钙含量由主干一主枝一结果枝一叶片逐渐增加。在各器官中钙主要以醋酸溶钙和盐酸溶钙的形式存在。  相似文献   

10.
不同时期采收的草莓果实糖含量差异的代谢机理   总被引:3,自引:0,他引:3  
 以促成栽培的‘枥乙女’草莓为试材,分析了不同月份采收的果实糖含量和蔗糖代谢相关酶活性的变化。结果表明,不同时期采收的草莓果实糖含量有差异,成熟果实的总糖和蔗糖含量以2月份采收的最高,1月份次之,4月份最低;不同月份果实糖含量不同主要由蔗糖含量的差异引起。2月份果实的蔗糖磷酸合酶(SPS)、蔗糖合酶(SS)合成方向活性显著高于1月份,而转化酶活性显著低于1月份,这样有利于2月份成熟果实的蔗糖积累。4月份成熟果实的SS(合成方向)、SPS和酸性转化酶(AI)活性水平均与2月份相近,但此时果实仍不能积累蔗糖,表明4月份草莓果实不能积累蔗糖与糖代谢关系不密切。  相似文献   

11.
Changes in the distribution of dry matter and nonstructural carbohydrates in various parts of young ‘Fuyu’ persimmon (Diospyros kaki) were examined with 3- and 4-year-old trees with (fruited) and without fruits (defruited). The effect of such changes was then monitored with regard to the magnitude of new growth the following year. From June 15 to November 1, fruiting significantly decreased the rate of dry weight accumulation in perennial parts of the tree. Dry matter was partitioned the most to fruits (68–72%) and the least to the roots. Of the total dry weight, root accounted for 8–27% in fruited and 58–62% in defruited trees. During this period, soluble sugars were three times more in fruited than in defruited trees, but more than 95% of sugars were in the fruits. Starch content increased in defruited trees, more than 93% of which being distributed to the perennial parts. Compared with fruited trees, defruiting in the previous year increased new shoot growth and the number of fruits the following year, with a 20–58% greater increase in dry matter. During the new growth from April 10 to June 10 the following year, root dry weight decreased by 30–32% in defruited trees, whereas it increased by 20–80% in the fruited ones. Soluble sugars in roots decreased by 8.8–19.7 g in defruited trees but increased by 9.7–12.3 g in fruited ones. Starch in roots decreased by 68–75.1 g in defruited trees but increased by 10.2–13.3 g in fruited ones. However, there were no significant differences in soluble sugars and starch in the newly grown parts. It was estimated that a 1-g difference in dry matter accumulated in the previous season resulted in a 116-mg and 256-mg difference in dry weight of newly grown parts, and a 6.5-mm and 17.5-mm new shoot in the following season for 3- and 4-year-old trees, respectively.  相似文献   

12.
It has been widely appreciated that animal cells rely on the mechanism of regulatory volume decrease(RVD) after swell in a hypotonic environment. Activation of K channels is crucial in the process of self-protection. There are a characterized increase in cytoplasmic Ca and a decrease in pH in the process of RVD in many cell types. Ca entry via transient receptor potential(TRP) channel is crucial for the cytoplasmic Ca increase, which in turn induces the decrease in pH.The increase in cytoplasmic Ca and decrease in pH activate or inhibit the activity of K channel, respectively. In this review, the regulatory network at cellular level between cytoplasmic Ca and pH, and the modulation of K channels by Ca and pH in the process of RVD are discussed.  相似文献   

13.
Abstract

Producing strawberry transplants from runner tips that were plugged ~1 month earlier (early July) than the standard time (early August) promoted fall flowering in some short-day strawberry cultivars. In 2002,100% of ‘Chandler’ transplants produced in early July flowered in the fall, but none of the August-plugged ‘Chandler’ transplants flowered in the fall. In 2003, 73% of ‘Chandler’ transplants produced in mid-July from average-size runner tips and less than half of transplants from small-size runner tips flowered in the fall. Again, August-plugged plants did not flower in the fall. Flowering was absent in ‘Northeaster’ plants. Under protected cultivation, July-plugged ‘Sweet Charlie’ plants bloomed earlier and produced more fruit in November and December than those plugged in August. This study showed that fall flowering in ‘Chandler’ and ‘Sweet Charlie’ strawberry is possible if the transplants are prepared by plugging runner tips in early July. This novel technique for propagating strawberry transplants for annual plasticulture combined with production under high tunnels creates an opportunity for strawberry production in early winter and again in the spring (double cropping) in the mid-Atlantic coast region.  相似文献   

14.
AIM:To investigate the anti-inflammatory e ffect of partial liquid ventilation in the piglets with lung lavage-induced acut e lung injury.METHODS:16 piglets were treated by lung lavage to a partial pre ssure of oxygen in arterial blood (PaO2) below 100 mmHg for one hour and rando mly divided into mechanical ventilation group (MV group) and partial liquid vent ilation group (PLV group).Blood-gas analysis,hemodynamics,the contents of TNF-α,MD A,SOD,and MPO activity in lung tissue were measured.RESULTS:(1) Lung W/D,PPI and the count of WBC in the BALF in P LV group were significantly lower than those in MV group.The contents of MDA an d MPO in lung tissue in PLV group were significantly lower than those in MV grou p.However,no evident difference in SOD activity in lung tissue between two gro ups was observed.(2) The contents of TNF-α in lung tissue in PLV group were si gnificantly lower than those in MV group.CONCLUSION:Partial liquid ventilation with perfluorocarbon has anti-inflammatory effect on lung lavage-induced acute lung injury in the piglets .  相似文献   

15.
杨桃新梢花芽分化及其碳水化合物含量的变化   总被引:2,自引:0,他引:2  
武萍萍  周碧燕 《园艺学报》2007,34(5):1151-1156
 以6年生盆栽甜杨桃为材料,观察了新梢上各节位芽的分化情况,比较了新梢上不同节位的碳水化合物含量。结果表明:当第2节位开始“露红”(肉眼可辨红色的花芽)时,新梢上各节位上的芽(顶芽除外)基本上进入形态分化阶段。第3和第4节位“露红”的枝条,韧皮部和木质部可溶性糖含量比第1位和第2位“露红”的枝条高。徒长枝第1节位的可溶性糖和淀粉含量都较高,第3、第5节位的含量与第1或第2节位“露红”的成花枝上相应节位的含量相当。本研究结果表明,杨桃新梢上的芽在进行形态分化的过程中,枝条仍在积累碳水化合物。  相似文献   

16.
The effects of combinations of salinity and water table on the mineral content of plum and peach were studied in lysimeters.Chloride content (Cl) in the leaves and the roots of plum and in the leaves of peach increased with salinity, whereas Cl in peach roots was not affected. Leaves of peach contained higher amounts of Cl than the leaves of plum. The opposite trend was observed in the roots.Sodium content (Na) increased with salinity in plum, whereas in peach it was not affected.The effect of salinity on calcium content (Ca) was not consistent in plum and peach.Potassium content (K) in the leaves of plum and peach decreased with salinity, whereas in the roots it was not affected.The Ca/K ratio in plum leaves increased with salinity, whereas in peaches it decreased in the 4000 p.p.m. treatment.Leaf phosphorus content (P) in the plum and the ‘Balady’ peach decreased with salinity, while in ‘Mit Ghamre’ peach it was not consistently affected. In plum root, P increased with salinity, whereas the effect was the opposite in peach.Magnesium content (Mg) was not significantly affected.The depth of the water table had no consistent effect on the Cl, Na, Ca, K, Ca/K ratio, P and Mg contents in the leaves and roots of plum or peach.The interaction between salinity treatments and water table levels was not significant in most cases.  相似文献   

17.
AIM: To examine the expression and distribution of tumor necrosis factor-α (TNF-α), tumor necrosis factor receptor I (TNFR I) and apoptosis in oral lichen planus, and evaluate their roles and relation in the oral lichen. METHODS: Immunohistochemical technique and TUNEL were employed to study the expression of TNF-α, TNFR I and apoptosis in 50 cases of oral lichen planus and 10 normal oral mucosa specimens. RESULTS: Compared with the normal control group, TNF-α expression was upregulated in mononuclear cells in lamina propria and decreased in keratinocytes in oral lichen planus lesion (P<0.05). On the contrary, TNFR I expression was increased in keratinocytes and decreased in lamina propria in oral lichen planus lesion (P<0.05). The increased apoptosis index in keratinocytes and the decreased apoptosis index in lamina propria were found in oral lichen planus (P<0.05). CONCLUSION: The accelerated apoptosis of keratinocytes and the inhibition of lymphocytes apoptosis may contribute to the formation and progression of oral lichen planus.  相似文献   

18.
The deposition of calcium in tomato fruit grown at a range of salinities (electrical conductivities between 3 and 17 mS cm“1), with or without IAA-transport inhibitor treatment, was investigated. Calcium (Ca) in the flesh and pulp of tomato fruit was sequentially separated into four fractions: FI soluble in water, FII soluble in 2.5 mol dm“3 NaCl, Fill soluble in 2% acetic acid and FIV soluble in 5% HC1. In mature fruit, grown at 3 mS cm“1, more than half the Ca was in FI, and the Ca concentration was higher in the pulp than in the flesh. FII and Fill each contained less than 20% of the Ca, and the Ca concentration was higher in the flesh than in the pulp. In general, salinity reduced the concentration of Ca in all fractions and slightly altered the proportional distribution of Ca in fractions. The deposition of calcium in young fruit, grown at 3 and 8 mS cm“1, was highest in FII in the flesh or in FI in the pulp. When 45Ca was supplied to detached fruit, the patterns of45 Ca distribution in the fractions were similar to that of total Ca. Treatment with an IAA-transport inhibitor, CME, reduced both the uptake and transport of 45Ca. While the amount of 45Ca in all fractions was significantly reduced by CME, the proportional distribution of 45Ca among fractions was not affected substantially. Although the proportional deposition of Ca in different fractions was not significantly affected by either salinity or CME, further reduction of the intrinsically low deposition of Ca in FII of distal pulp caused by these factors may be the cause of blossom-end rot in tomato fruit.  相似文献   

19.
为分析苹果试管种质端粒长度与繁殖能力、衰老的关系,探索端粒长度与苹果试管种质离体保存年限的关系,对保存多年的不同继代次数的3个苹果品种试管苗进行了表型、增殖能力以及端粒长度的研究。结果表明:保存了8~33年的‘富士’、保存8~27年的‘金冠’和保存8~25年的‘嘎拉’苹果茎尖试管苗继代增殖能力大部分没有变化,表型未发生明显变化;3个品种不同继代次数30 d苗龄试管苗叶片端粒长度均差异不显著;继代73代苗龄分别为10、30、50和90 d的试管苗叶片端粒长度变化因品种而异,‘富士’‘嘎拉’差异不显著,‘金冠’50 d苗龄的最长,90 d苗龄的最短;继代71代苗龄30 d的‘金冠’试管苗茎段端粒长度显著高于叶片,茎段和愈伤组织、叶片和愈伤组织之间差异不显著,‘嘎拉’表现为愈伤组织>叶片>茎段。苹果试管苗端粒长度变化与其增殖能力、表型及同一继代周期内衰老程度的变化相吻合。  相似文献   

20.
采用Fluo-3 AM-ester探针研究桃不同组织的Ca^2+信号分布   总被引:1,自引:0,他引:1  
鲁振华  王志强  彭斌  牛良  崔国朝  刘淑娥 《果树学报》2011,(5):915-917,I0001
钙作为植物最重要的矿质元素之一,在植物生理和生化活动中起重要作用。采用激光扫描共聚焦显微镜,以Fluo-3 AM-ester为荧光探针研究了桃果肉和叶柄组织中Ca2+的分布,结果表明Fluo-3 AM-ester可作为荧光探针对桃不同组织中游离的Ca2+信号强度和分布特征进行分析。不同的物镜观察(10×和20×)下,C...  相似文献   

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