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1.
硅对黄瓜白粉病抗性的影响及其生理机制   总被引:20,自引:1,他引:20  
以黄瓜感病品种为材料,研究了施硅和诱导接种白粉菌对抗坏血酸过氧化物酶(AsA-POD)、脱氢抗坏血酸还原酶(DR)、苯丙氨酸解氨酶(PAL)、多酚氧化酶(PPO)活性与酚类物质含量变化的影响。结果表明:诱导接种后,营养液中加硅酸盐显著降低黄瓜白粉病病情指数,显著提高了黄瓜叶片中AsA-POD、PPO的活性,而DR、PAL活性低于不施硅处理,但差异不显著。施硅处理的酚类物质含量较高,并显著降低病情指数。  相似文献   

2.
It has been suggested that salicylic acid (SA) is a signal in acquired resistance to pathogens in several plants. Also, it has been suggested that infestation of plants causes an increase in the activity of phenylalanine ammonia-lyase (PAL), a key phenolic biosynthesis enzyme. The purpose of this work was to investigate whether the induction of SA and PAL activity is related to the susceptibility of barley to aphid infestation. The induction of free and conjugated SA in two barley cultivars that differ in susceptibility to aphids was analyzed. Analyses of several physiological parameters showed that cv. UNA-80 was more susceptible to the aphid Schizaphis graminum than cv. LM-109. Salicylic acid was not detected in noninfested plants. Levels of free and conjugated SA in cv. LM-109 and of conjugated SA in cv. UNA-80 increased with aphid infestation, whereas the levels of free SA in cv. UNA-80 remained high under all infestation degrees. Maximum values reached in both cultivars were not significantly different. With respect to PAL activity, cv. LM-109 showed a significantly higher specific activity than cv. UNA-80, the more susceptible cultivar. The relationship between the susceptibility of a plant to aphid and SA induction and PAL activity is discussed.  相似文献   

3.
The effects of nitrogen (N) supply on nitrogen metabolism in leaves of Chrysanthemum morifolium Ramat. were examined in five different stages throughout the growing season. The results suggested that flavonoids content was positively related to phenylalanine ammonia-lyase activity through the whole growing stage of the plant but with a decreasing correlation coefficient for increasing nitrogen supply. There was no correlation between flavonoids and 4-coumarate coenzyme A ligase. Soluble protein content was positively correlated with phenylalanine ammonia-lyase activity because there was little competition for the phenylalanine in the leaves under low nitrogen supply. Phenylalanine ammonia-lyase activity decreased gradually with increasing nitrogen supply because of the competition for the phenylalanine in protein synthesizes. The results suggest that nitrogen nutrition plays a key role in biosynthesis of enzymes in the leaves of C. morifolium.  相似文献   

4.
Influence of lysozyme treatments on champagne base wine foaming properties   总被引:1,自引:0,他引:1  
The objective of this study was to estimate the effect of lysozyme on the foaming characteristics of Champagne base wine. Lysozyme additions were made to the musts and also to the wines before and after bentonite or charcoal treatments, which remove endogenous proteins. Treatments with bentonite diminished foamability and foam stability of wines, whatever the dose (30 or 80 g/hL) and variety [Chardonnay, -28%; Pinot noir, -20% (at 30 g/hL)]. An addition of lysozyme in must raised Pinot noir wine foamability by 21%, whereas the difference is hardly perceptible for Chardonnay wine (+3%). Pinot noir and Chardonnay wines, originating from lysozyme-treated musts, in addition to bentonite treatment on the wine, presented higher foamability than wines treated only with bentonite. Lysozyme was removed (91-100%) by the bentonite treatment. Then, it was not responsible for the increase in foamability but seemed to have a protective effect on the wine proteins. When wines were initially treated with bentonite (150 g/hL) and then enriched with 80 g/hL lysozyme, this enzyme was not able to restore foaming properties. Treatments with charcoal always diminished foamability. The average increase in foamability due to an addition of lysozyme after charcoal treatment (80 g/hL) was 23%. Results showed a real positive effect of lysozyme on foam stability when wines have to be treated with charcoal (+25% and +56% for the Pinot noir wine and the Chardonnay wine, respectively, at 30 g/hL).  相似文献   

5.
In an attempt to develop a technique for the identification of grape cultivars in commercial wines, a method for the extraction of DNA from must and experimental wines was adapted and optimal PCR conditions for the amplification of this DNA were established. DNA was analyzed during the fermentation process for six cultivars (Chardonnay, Clairette blanche, Grenache noir, Merlot, Muscat blanc à petits grains, and Syrah). The extractions were performed on solid parts in suspension as well as on the aqueous fraction. Expected profiles for these cultivars were obtained with DNA extracted from the solid parts during all of the fermentation process and for the wine. The analysis of DNA extracted from aqueous fractions was less reproducible, and microsatellite amplifications were obtained only in the case of Clairette blanche, Merlot, and Syrah wines. Results demonstrate that the purification process is adequate for the analysis but that the DNA concentration represents the main limiting factor. Technical improvements of the method are discussed.  相似文献   

6.
Polyphenols in grapevine can be constitutive or induced, depending upon cultivar, plant organ, and environmental influences. The aim of the presented work was to develop and optimize a liquid chromatography-tandem mass spectrometry (LC-MS/MS) method to study the pattern and amount of selected polyphenols in leaves of Vitis vinifera L. The method is simple and does not require any sample cleanup. It covers representative metabolites of the structure classes cinnamic acids, flavonoids, and stilbenes and enables the simultaneous separation and quantification of 13 polyphenols within 9 min at concentration levels between 0.1 and 3 μg/g. We present the method performance characteristics and its application to the quantification of polyphenols in grapevine leaves of the cultivars Riesling and Pinot noir. A total of 7 of 13 target polyphenols were detected at concentrations above the limits of quantification. Interestingly, instead of the expected trans-resveratrol, the investigated leaf samples of both cultivars contained cis-resveratrol-3-O-glucoside. The measurements also showed that Riesling leaves tended to contain higher concentrations of the selected polyphenols than Pinot noir. In view of its intended future use, the developed method has been shown to be a powerful and fast tool to study polyphenols in grapevine leaves subjected to environmental stress conditions.  相似文献   

7.
以裸仁美洲南瓜抗、 感病品种为材料,测定了硅酸钠溶液喷雾处理南瓜幼苗后诱导接种白粉菌对不同抗病品种裸仁美洲南瓜叶片中酚类物质、 绿原酸、 类黄酮3种物质在不同处理时期含量变化的影响。结果表明,硅酸钠诱导处理后不同抗性品种南瓜叶片中的酚类物质、 绿原酸、 类黄酮等物质含量均明显升高,抗病品种中酚类物质含量在第5 d、 7 d、 9 d时分别高于对照和接菌处理的,绿原酸含量在各个处理时间均高于对照和接菌处理的,类黄酮含量在第7 d、 9 d时分别高于对照和接菌处理的; 感病品种中酚类物质含量和绿原酸含量分别在第5 d、 7 d和9 d时高于对照和接菌处理; 类黄酮含量在第3 d、 5 d、 7 d和9 d时均高于其他处理; 硅酸钠诱导处理后,大多数情况下抗病品种的酚类物质(除第7 d外)、 绿原酸(除第7 d、 9 d外)、 类黄酮等含量均高于感病品种,差异显著,且在接种后第10 d和第15 d白粉病病情指数明显下降。  相似文献   

8.
Latent infection was analyzed when harpin at 50 mg/L was sprayed on muskmelon 4 times at four different stages: florescence, young fruit, fruit enlarging, and netting periods. Results showed that the latent infection was significantly lower in sprayed muskmelons than in the control fruit. Meanwhile, the activities of peroxidase, phenylalanine ammonia-lyase, β-1,3-glucanase, and chitinase increased significantly in the fruit treated with harpin. It also resulted in an increase of contents of total phenolic compounds, flavanoids, and lignin. In addition, the treatment of harpin increased the activity of superoxide dismutase, enhanced the content of hydrogen peroxide, and reduced catalase activity. Furthermore, harpin treatments contributed to the reinforcement of cell walls of pericarp in fruit, the reduction of postharvest decay, and the improvement of postharvest qualities. These results suggested that harpin effectively participated in inducing resistance and could be a new strategy for preventing latent infection in muskmelon.  相似文献   

9.
在溶液培养条件下,以水稻抗病品种91SP和感病品种Lemont为材料,研究施硅和接种纹枯病菌对水稻纹枯病发生情况、外切几丁质酶、内切几丁质酶和β-1,3-葡聚糖酶活性的影响。结果表明,施硅能降低抗病品种91SP的纹枯病病级和病情指数,显著降低感病品种Lemont的病级和病情指数。在未接种纹枯病菌条件下,施硅增加了抗病品种几丁质酶活性,增加了感病品种的几丁质酶活性,但对β-1,3-葡聚糖酶活性影响不大。接种纹枯病菌后,水稻几丁质酶活性被迅速激活后又下降,施硅通过提高抗病品种91SP几丁质酶和β-1,3-葡聚糖酶活性,以及通过提高感病品种Lemont几丁质酶活性来增强对纹枯病的抗性,但感病品种Lemont施硅处理的几丁质酶活性降低幅度小于抗病品种91SP。  相似文献   

10.
We describe here techniques to detect and quantify lysozyme in Pinot noir and Chardonnay Champagne wines. Using a dot-blot technique, lysozyme antibodies were able to recognize their antigens even when the concentration of lysozyme in wine was 75 mg/L. SDS-PAGE was the second technique used. After Coomassie Brilliant Blue (CBB) staining or antibody immunostaining was performed, the wine originating from the lysozyme-treated must gave only one band corresponding to the lysozyme. It is then possible to precisely determine the concentration of lysozyme in a must or a wine by densitometric measurement of this band. The control wine gave no band with the CBB staining, such as with the immunostaining. The quantification of lysozyme with HPLC is another useable technique because the lysozyme elution time is largely superior to that of all of the wine compounds. In wines, losses of lysozyme were higher when the enzyme was added at one time to the must (-34% for the Pinot noir and -37% for the Chardonnay) than when lysozyme is added in 2-fold both in the must and in the wine (around -26% for the two wines). The lowest diminution is observed when lysozyme was added to the wine only (-18%) in comparison to the addition to the must at 300 mg/L (-43%).  相似文献   

11.
The effect of wounding on polyphenol oxidase (PPO), peroxidase (POD), and phenylalanine ammonia-lyase (PAL) was studied in six minimally processed lettuce (Lactuca sativa L.) cultivars upon storage for 7 days at 5 degrees C (Iceberg Mikonos (IM), I. Green Queen (IGQ), I. Asdrúbal (IA), Little Gem Sandra (LGS), Romaine Cazorla (RC), and R. Modelo (RM)). Wounding of lettuce tissue midribs (because of minimal processing) caused an exponential increase in PPO activity due to the activation process from latent to fully active PPO by following first order kinetics in the time range from 3.7 days (LGS) to 6.3 days (RC). However, total PPO activity (active plus latent) remained constant. Isoform pattern of PPO changed upon storage probably because of posttranslational processes. POD activity linearly increased with induction of new POD isoenzymes. PAL activity presented a typical bell-shaped induction pattern in four cultivars. Only IM and IGQ showed a second induction response which has not been previously described in the literature. IM was the cultivar most susceptible to browning and RC was the cultivar least susceptible. However, no clear correlation was observed between browning and any of the biochemical and physiological attributes investigated (PPO, PAL, and POD activities, total and individual phenols accumulation, and ascorbic acid content).  相似文献   

12.
硅对水稻防御性关键酶活性的影响及其与抗稻瘟病的关系   总被引:4,自引:1,他引:4  
通过室内溶液培养试验,研究了硅酸盐对接种稻瘟病菌后水稻的病情指数、植株生物量、过氧化物酶(POD)、多酚氧化酶(PPO)和苯丙氨酸解氨酶(PAL)活性的影响。结果表明,施硅能显著降低水稻稻瘟病的发病率和病情指数,防治效果达60.59%;显著减轻稻瘟病对水稻地上部的危害,干物质量显著高于不施硅处理,但对地下部生长影响不明显;接种后水稻叶片POD活性均升高,在第5 d达到最大值,施硅处理显著低于不施硅处理,与稻瘟病抗性成负相关;水稻叶片PPO活性在接种后第5 d达到峰值,从第4 d开始施硅处理显著高于不施硅处理;接种后水稻叶片的PAL活性快速升高,在第24 h达到最大值,施硅处理显著高于不施硅处理,是其1.44倍。说明硅能提高防御性关键酶的活性,参与水稻本身防卫机制,通过一系列的生理生化作用来增强水稻的抗性。  相似文献   

13.
L-arginine is the precursor of nitric oxide (NO). In order to examine the influence of L-arginine on tomato fruit resistance, preharvest green mature tomato fruits (Solanum lycopersicum cv. No. 4 Zhongshu) were treated with 0.5, 1, and 5 mM L-arginine. The reduced lesion size (in diameter) on fruit caused by Botrytis cinerea, as well as activities of phenylalanine ammonia-lyase (PAL), Chitinase (CHI), β-1,3-glucanase (GLU), and polyphenoloxidase (PPO), was compared between L-arginine treated fruits and untreated fruits. We found that induced resistance increased and reached the highest level at 3-6 days after treatment. Endogenous NO concentrations were positively correlated with PAL, PPO, CHI, and GLU activities after treatment with Pearson coefficients of 0.71, 0.94, 0.97, and 0.87, respectively. These results indicate that arginine induces disease resistance via its effects on NO biosynthesis and defensive enzyme activity.  相似文献   

14.
为阐明硅提高水稻抗稻瘟病的生理机制,采用室内溶液培养试验,研究了硅对接种稻瘟病菌后水稻叶片的几丁质酶和β-1,3-葡聚糖酶活性以及总可溶性酚和木质素含量的影响。结果表明,接种稻瘟病菌能诱导几丁质酶活性的快速上升,不施硅处理的几丁质酶活性在第2 d达到第一个峰值后就开始下降,而施硅处理的几丁质酶活性则继续上升直到第4 d才开始下降,从第4~8 d显著高于不施硅处理。β-1,3-葡聚糖酶活性在接种后的第4 d之前均上升缓慢,处理间差异不显著;第4 d后开始上升,到第8 d达到最大值;不施硅处理上升更快,显著高于施硅处理。接种稻瘟病菌能诱导水稻叶片总可溶性酚含量快速上升,施硅处理和不施硅处理分别在接种后的第3和第4 d达到峰值,并开始快速下降;施硅能显著提高总可溶性酚含量。水稻叶片中的木质素含量在接种后的第1 d快速上升,并维持较高水平,施硅处理显著高于不施硅处理;但在感病后期(第6 d),施硅处理开始显著低于不施硅处理。  相似文献   

15.
The initial objective was to confirm evidence, obtained from field grown plants, for iron (Fe) accumulation in leaves under ozone exposure. Tobacco plants were grown in pots under either open air or growth chamber conditions. The ozone-sensitive cultivar Bel W3 showed symptoms of ozone injury only when grown outside, while the cultivar Virginia never developed symptoms. In both cultivars, basal leaves of plants grown outside had higher concentration of Fe, but not of manganese (Mn) or zinc (Zn), than those from the growth chamber. Results suggest an interference of the oxidative stress with the mechanisms regulating Fe homeostasis. A second objective was to test whether differences in tolerance to ozone correspond with differences in tolerance to Fe toxicity. Iron toxicity was induced by supplying an excess of Fe-EDTA to plants, grown hydroponically in a growth chamber, upon partial root cutting. Symptoms in leaves were more severe in Bel W3 than in Virginia, which suggested that mechanisms of tolerance to ozone were also effective against Fe toxicity. In both cultivars, a good correlation was determined between Fe accumulation and ethylene production in the leaves.  相似文献   

16.
The main arctic bramble ( Rubus arcticus) cultivars are susceptible to downy mildew ( Peronospora sparsa), which seriously threatens the cultivation. The efficiency of Aliette, Euparen M, phosphite-containing Phosfik, Phostrol, Farm-Fos-44, and Kaliumfosfiet, as well as Bion was evaluated in the greenhouse. Fewer symptoms and less Peronospora DNA were found in plants treated with Euparen M and Bion, whereas Aliette, Phosfik, and Phostrol gave moderate protection. Three arctic bramble cultivars showed varying susceptibility to P. sparsa. An inexpensive and fast in vitro plate test gave results parallel with those obtained in the greenhouse. Quantitative differences were found in the phenolic profiles of the leaves of different cultivars and in different treatments. Several phenolic compounds were tentatively identified in arctic bramble for the first time, for example, monomeric and oligomeric ellagitannins and galloylglucoses. Negative correlation was found between the amount of P. sparsa DNA and flavonol glycosides and some ellagitannins in the leaves 8 days after inoculation, suggesting a possible role for these phenolics in the defense.  相似文献   

17.
Abstract

Crop yield and quality are limited by different biotic and abiotic factors. This study focused on the ability of phenylalanine ammonia-lyase, ascorbate peroxidase and polyphenol oxidase to impart resistance to mineral deficiencies. Tomato plants (Lycopersicon esculentum L.) were grown for 48, 72 and 96?hr with different specific deficiencies of minerals, including Mg2+, Ca2+, Fe2+, PO42?, K+, NO3? and SO42?, and then the soluble protein content and enzymatic activities (phenylalanine ammonia-lyase, polyphenol oxidase and ascorbate peroxidase) were analyzed. The impact of the mineral deficiencies varied in the tomato leaves. Mineral deficiencies that caused early significant protein accumulation were detected in tomato leaves grown in hydroponic cultures deficient in Ca2+, PO42? and NO3? after 48, 72 and 96?hr of incubation, whereas the soluble protein level was drastically reduced in tomato leaves grown in cultures deficient in Mg2+, Fe2+, K+ and SO42? that reveal remarkable time-dependent increase in resistance-related enzymes' activities. The resistancerelated enzymes' activities were not correlated with the soluble protein levels. These findings suggest that these activities depend on the amount of foliar nutrients, particularly Mg2+, Fe2+, K+ and SO42?. These nutrients act synergistically on the phenolic compound biosynthesis and degradation-dependent enzymes, and this synergistic process could be considered as a mechanism of acclimation for plants against specific mineral deficiencies.  相似文献   

18.
The development of iron deficiency symptoms (growth depression and yellowing of the youngest leaves) and the distribution of iron between roots and leaves were investigated in different vine cultivars (Silvaner, Riparia 1G and SO4) grown in calcareous soils. As a control treatment all cultivars were also grown in an acidic soil. Only the cultivars Silvaner and Riparia 1G showed yellowing of the youngest leaves under calcareous soil conditions at the end of the cultivation period. All cultivars including SO4 showed severe shoot growth depression, by 50 % and higher, before yellowing started or without leaf yellowing in the cultivar SO4. Depression of shoot growth occurred independently from that of root growth. In a further treatment the effect of Fe‐EDDHA spraying onto the shoot growth of the cultivar Silvaner after cultivation in calcareous soil was investigated. Prior to Fe application plants were non‐chlorotic, but showed pronounced shoot growth depression. Spraying led to a significant increase in shoot length, though leaf growth was not increased. Accordingly, depression of shoot growth of non‐chlorotic plants under calcareous soil conditions and with ample supply of nutrients and water has been evidenced to be at least partly an iron deficiency symptom. We suggest that plant growth only partially recovered because of dramatic apoplastic leaf Fe inactivation and/ or a high apoplastic pH which may directly impair growth. Since growth was impaired before the youngest leaves showed chlorosis we assume that meristematic growth is more sensitively affected by Fe deficiency than is chlorophyll synthesis and chloroplast development. In spite of high Fe concentrations in roots and leaves of the vines grown in calcareous soils plants suffered from Fe deficiency. The finding of high Fe concentrations also in young, but growth retarded green leaves is a further indication that iron deficiency chlorosis in calcareous soils is caused by primary leaf Fe inactivation. However, in future, only a rigorous study of the dynamic changes of iron and chlorophyll concentration, leaf growth and apoplastic pH at the cellular level during leaf development and yellowing will provide causal insights between leaf iron inactivation, growth depression, and leaf chlorosis.<?show $6#>  相似文献   

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