Search

ABSTRACT Plants play an essential role in the ecological cycle; however, they face numerous global biotic and abiotic stress factors. The capacity of plants to survive in adverse conditions is called stress tolerance. Drought stress is among the major stresses faced by plants, as arid conditions affect plant development and productivity, crop yield, relative water content, nutrient intake, photosynthesis, dry matter accumulation, and respiration. Hormones play an essential role in plant stress metabolism. Until recently, it was thought that plant hormones consisted of five groups: auxin, gibberellin, cytokinin, abscisic acid, and ethylene. However, other substances synthesized by plants, such as jasmonates, brassinosteroids, salicylic acid, and nitric oxide, have also shown critical vital functions in the plant, like the hormones. Another hormone in these substances is strigolactone (SL), which has been reported to perform essential functions in stress physiology. This research investigated the effects of SL applications on drought stress on 1103 Paulsen American Grapevine Rootstock. GR24, a synthetic analog of SLs, was applied to grapevine rootstock. Physical and biochemical changes were determined (chlorophyll, membrane injurity, prolin, lipid peroxidation, soluble protein, superoxide dismutase, ascorbate peroxidase activities, phenolic compounds, plant hormones, and mineral elements). The results show that GR24 applications effectively alleviate the harmful effects of drought stress in most features.

Adolescence is established as an important stage in the human being, we try to show how positive or negative this stage can be in the development of an adequate environment, elucidating the benefits or consequences that can affect the psychomotor devel-opment of a person. Adolescence is the time when the personality of an individual is defined, influenced by various factors that can help the subject to develop adequately in society, as well as fac-tors that can affect the subject conditioning him/her to an environ-ment that is not favorable for his/her development. Both physical and psychological changes are mentioned, as well as hormonal factors which play an important role in development. It is intend-ed to demonstrate the hormonal mechanisms that condition the changes in the development of the human being

Introduction and purpose: Polycystic ovary syndrome (PCOS) is the most common endocrine disease in the female reproductive age. As treatment guidelines include lifestyle changes, various diet types are being evaluated in terms of efficacy among them ketogenic diet (KD) which was also assessed in terms of its influence on another ovarian related disease - ovarian cancer. The aim of this paper is an analysis of the available scientific data in respect of the role of the KD as a part of the therapy of ovarian related disorders. The search was conducted using PubMed and Google Scholarship databases. Brief description of the state of knowledge: Ketogenic diet demonstrates favorable effects in the hormonal profile of PCOS-affected women. It was also noticed that its administration results in the reduction of BMI and the improvement in glycemic parameters. Most of the research was conducted by linking the ketogenic diet with the caloric restriction. In the matter of ovarian cancer the results are unclear; some of the research states the improvement of the quality of life of the participants, but there is some alarming data of the possible role of KD in enhancing the tumor growth. Conclusions: Ketogenic diet merits further research as a possible factor in the treatment of PCOS as foregoing results are pointing to its efficacy. Nevertheless, still more data is needed to determine its role as studies were conducted within a short period of time with relatively small research groups. There are also other limitations such as the lack of comparison with other dietary patterns with the caloric deficit which makes it difficult to deduce the main profitable factor. When it comes to ovarian cancer the results of the current data are also unclear and unambiguous with the possible negative effects.

ABSTRACT Physiological dormancy of Vitis vinifera seeds jeopardises breeding programs and biodiversity evolution. To increase the knowledge on dormancy breaking, seeds of white and black Sardinian grape cultivars (cvs) were exposed to different pre-germination treatments. To shed light on the physiological and structural factors involved in seed dormancy, the contents of oil, abscisic acid, gibberellic acid, 3-indolacetic acid, condensed tannins, and total polyphenols were determined. In addition, sectioned seeds were observed by SEM to determine the morphological and anatomical characteristics. Dormancy break in white, but not in black grape seeds, occurred under almost all imposed pre-germination treatments. Among red cvs, only seeds from ‘Cagnulari’ germinated when kept at 25 °C. Chilling seeds of the white cvs ‘Malvasia sarda’ and ‘Vernaccia di Oristano’ for 30 d resulted in the most effective treatment. Compared to white cvs, seeds of red ones owned 7 times higher levels of abscisic acid however, gibberellic acid content resulted 4 times less. Concerning the coat characteristics, red cv seeds had a thicker cuticle (6-10 µm) than white (4-6 µm) ones, however the most significant diversities were found for the inner integument, where in addition to size variances, palisade cell wall were structurally different.

Background. It is known about wide variety of individual reactions to stress explained by genetics factors. On the other hand, it is also known about aerobic fitness variability between individuals. From the above it follows the hypothesis that inter-individual differences in normal conditions determine the characteristics of the body's response to acute stress. The purpose of this study is to test the hypothesis. Material and methods. The experiment is at 58 rats (28 males) Wistar line. Animals were tested for resistance to hypoxic hypoxia and aerobic muscular performance by swimming test. On the basis of the received data two qualitatively equivalent groups in a ratio 10/48 were formed. After a week of recovery over the next 10 days, one animal remained intact and 5 other rats were exposed to water-immersion and restraint stress. The next day after stress, the ECG recorded and some endocrine, metabolic and immune parameters determined as well as erosive-ulcerative lesions of the gastric mucosa evaluated. Results. Four clusters by hypoxic and swimming tests were created retrospectively: normal resistance to hypoxia and muscular endurance (n=11); moderately reduced resistance to hypoxia and normal swimming test (n=25); drastic increased swimming test and normal hypoxic test (n=3); significantly increased resistance to hypoxia and normal swimming test (n=9). Each cluster is characterized by specific (correctness of classification 100%) post-stress changes in 6 neuro-endocrine, 12 immune, 10 metabolic and 2 ECGs parameters, as well as the index of damage to the gastric mucosa. The swimming test determines the post-stress state of the registered parameters by 63,8%, the hypoxic test - by 57,5%, and taken together - by 79,1%. Conclusion. The post-stress neuro-endocrine, immune and metabolic parameters as well as injuries of myocardium and gastric mucosa in rats are determined significantly by innate muscular endurance and resistance to hypoxia.