Physiological response of Populus nigra 'Italica' to galling aphids feeding.

Although gall-inducing aphids, namely Pemphigus bursarius (L.) and P. phenax Börner et Blunck, are widely known as serious pests for their secondary hosts (lettuce and carrot, respectively), the physiological mechanism of their gall induction on Populus L. trees still requires a better understanding. In this study, we compared physiological parameters, i.e. H2 O2 , electrolyte leakage (EL ), MDA, APX and GPOD. Changes in physiological parameters were analysed in foliar tissues with galls and in the gall tissues themselves and compared to leaves without galls. Significantly higher H2 O2 levels were observed in P. phenax galls when compared to leaves with galls. In turn, the highest EL of cells and MDA content was in P. bursarius galls. Other samples had lower or similar oxidative stress marker levels to leaves without galls. APX and GPOD had similar activity profiles in galls of both aphid species. Their activity decreased significantly in gall tissues, where it was even ten-fold lower than in leaves without galls. Data generated in this study indicate that patterns of the physiological features, e.g. ROS accumulation and cell membrane integrity, of Populus leaves with galls and galls alone depends on the gall-inducing aphid species. Where decreased APX and GPOD activity, especially in gall tissues, indicated a reduction in the antioxidant potential of these neoformed structures.

Effect of Neuroterus quercusbaccarum (L.) galls on physiological and biochemical response of Quercus robur leaves.

Gall formation is associated with multiple changes in plant cells, which still requires a better understanding. In this study, galls caused by sexual generation (♀♂) of Neuroterus quercusbaccarum (L.) (Hymenoptera: Cynipidae) on pedunculate oak trees (Quercus robur L.) were used as a model. Cytoplasmic membrane condition, concentration of hydrogen peroxide (H2O2), the activity of antioxidant enzymes and amino acid decarboxylase as well as chlorophyll fluorescence parameters were determined. Changes in physiological and biochemical parameters were analyzed in foliar tissues with galls and gall tissues themselves and compared to control. The presence of galls on oak leaves caused an increase of lipid peroxidation level. A significant decline in H2O2 and TBARS content with the reduction of guaiacol peroxidase (GPX) and ascorbate peroxidase (APX) activity were observed in gall tissues. The activity amino acid decarboxylase, i.e., LDC, ODC and TyDC varied between samples, which may affect the content of amino acids. The presence of N. quercusbaccarum galls caused an insignificant increase of the chlorophylls, carotenoids and anthocyanin contents, while the content of pigments and their ratios in gall tissues was extremely low. Moreover, photosynthetic parameters (F0, Fm, Fv/Fm, Y, qP) were significantly decreased. Data generated in this study indicate that the development of N. quercusbaccarum galls on pedunculate oak leaves has a negative effect on host plant related to the disruption of cell membrane integrity, disturbance of photosynthesis and reduction of the antioxidant potential of the host plant.

Biochemical responses induced in galls of three Cynipidae species in oak trees.

Gall-making Cynipidae manipulate the leaves of host plant to form galls where offspring find shelter and food. The relationship between oak gallwasp and biochemical mechanisms of galls still requires a better understanding. So, in this research, protein and phenolic compound contents, as well as the activity of antioxidative enzymes and pathogenesis-related (PR) proteins were determined. Galls caused by asexual generation of Cynips quercusfolii L., Neuroterus numismalis (Fourc.) and N. quercusbaccarum L., as a model were used. All cynipid species modified the protein levels of gall tissues, but they cannot be treated as protein sinks. Significantly higher levels of phenols were observed in the galled leaves and galls of all cynipid species when compared with the control tissues. Peroxidase and polyphenol oxidase activity was usually low or showed no activity in galled tissues of all species. PR proteins, such as chitinase and ß-1,3-glucanase, had a similar activity profile. Their activity significantly increased in the leaves with galls of all cynipid species, especially those infested with C. quercusfolii. Data generated in this study clearly indicate that galling Cynipidae manipulate the biochemical machinery of the galls for their own needs. However, the pattern of the biochemical features of leaves with galls and galled tissues depends on gall-making species.

Physiological Response of Orchids to Mealybugs (Hemiptera: Pseudococcidae) Infestation.

The harmfulness of mealybugs resulting from sucking plant sap, secreting honeydew, and transmitting plant viruses can give them the status of serious pests. This study documents the influence of Pseudococcus maritimus (Ehrhorn) and Pseudococcus longispinus (Targioni Tozzetti) infestation on alterations in selected physiological parameters of Phalaenopsis x hybridum 'Innocence'. The condition of the cytoplasmic membranes was expressed as the value of thiobarbituric acid reactive substances. We have determined changes in the activities of catalase and guaiacol peroxidase and measured the following chlorophyll fluorescence parameters: maximum quantum yield of photosystem II (Fv/Fm), effective quantum yield (Y), photochemical quenching (qP), and nonphotochemical quenching (qN). The strongest physiological response of orchids was recorded in the initial period of mealybugs infestation. Prolonged insect feeding suppressed lipid peroxidation, peroxidase and catalase activity, as well as photosynthesis photochemistry. The pattern of changes was dependent on mealybug species. This indicated the complexity of the processes responsible for plant tolerance. Data generated in this study have provided a better understanding of the impact of two mealybug species infestation on Phalaenopsis and should be useful in developing pest management strategies.

The effect of mealybug Pseudococcus longispinus (Targioni Tozzetti) infestation of different density on physiological responses of Phalaenopsis × hybridum 'Innocence'.

Cultivated orchids are the most abundantly attacked by polyphagous mealybugs. This study documented how different density of mealybug Pseudococcus longispinus (Targioni Tozzetti) infestation is associated with a response of antioxidative systems of Phalaenopsis × hybridum 'Innocence'. The degree of cell damage, estimated by electrolyte leakage measurement and the level of thiobarbituric acid reactive substances (TBARS), the content of pigments as well as the activity of antioxidative enzymes and proline level, as measurements of stress and stress compensation in moth orchid were examined. The highest electrolyte leakage (E L) value among samples from colonized plants was found in the orchids from series III (50 individuals/plant), whereas the lowest in the plants from series II (20 individuals/plant). The TBARS content reached the highest level at the lowest number of feeding insects (series I). Peroxidase activity toward guaiacol was significantly increased in series I (5 individuals/plant). The highest catalase activity was recorded in plants colonized by the highest number of scale insects (series III). Whereas, the highest value of proline was in series II. The content of individual photosynthetic pigments (chlorophyll a, chlorophyll b and carotenoids) in plant tissues did not vary significantly between control and colonized orchids. The results have not confirmed hypothesis that the increasing number of mealybugs occurring on plant enhanced plant physiological response. The degree of longtailed mealybug infestation on plants was positively correlated only with electrolyte leakage and catalase activity in leaf tissues.

[Study on the content of certain elements in retained teeth]. / Badanie zawartosci wybranych pierwiastków w zebach zatrzymanych.

The content of calcium, phosphorus.potassium and zinc was determined in 21 retained canine teeth and in a control group of canine teeth erupted completely. In the measurement the method of X-ray fluorescence was used. The obtained results were subjected to statistical analysis. In relation to control canines the retained teeth contained significantly more calcium and phosphorus and significantly less potassium. No significant differences were found in zinc content.

[Age and content of certain mineral components in permanent teeth]. / Wiek a zawartosc niektórych skladników mineralnych w zebach stalych.

The chemical composition of the teeth is determined during its development, however, in the postdevelopmental period changes of inorganic components are possible, which have an important effect on the morphology, structure and chemical composition of teeth. Using the method of X-ray fluorescence the levels of Ca, P, Cl, S, K and Zn were determined in hard tissues of 218 permanent non-carietic teeth from all dental groups. The correlation between these various elements in the teeth and the age of the subjects, whose teeth were taken for the investigations, was expressed with the correlation coefficient r of Pearson. The significance of the correlation was analysed using Students t test. In case of significant correlation equations of regression were determined for predicting the expected value of the level of a given element in teeth for a given age. No significant differences were noted in the levels of Ca and P in relation to age. The levels of S, K and Zn rose with age, while the chloride content was decreasing.

[Potassium content analysis in healthy teeth in people of various ages]. / Analiza zawartosci potasu w zdrowych zebrach u ludzi w róznym wieku.

Potassium level in permanent teeth has been designated by X-ray fluorescence and some relationships of the content of this element between individual groups of teeth according to the age and sex have been proved. Average K level in molar teeth of men and women was 272.1 +/- 50 (M-SE) ppm, in premolar teeth--297.6 +/- 7.1 ppm, in cuspid teeth--287.0 +/- 7.5 ppm and in incisive teeth--324.7 +/- 12.3 ppm. Irrespective of the age potassium level in permanent teeth in men and women doesn't essentially differ. In the remaining groups of teeth but molar teeth potassium level essentially increases with the age. The greatest growth of potassium with the age has been observed in incisive teeth.