CLINICAL AND IMMUNOLOGICAL EFFECTIVENESS OF TREATMENT OF RAGWEED POLLINOSIS IN THE SAMARA REGION

Allergic rhinitis and bronchial asthma are widespread respiratory allergic diseases. In some territories of the Russian Federation, the dominant cause of pollinosis is ragweed. The aim of the study was to evaluate the clinical and immunological efficacy of ASIT with the allergen Ambrosia artemisiifolia in patients sensitized to Ambrosia trifida in the Samara region. Patients with proven sensitization to Ambrosia trifida was held immunotherapy with Ambrosia artemisiifolia allergoid preseason. After treatment, patients had a decrease in the severity of symptoms of allergic rhinitis according to VAS (p = 0.00001), a decrease in the need for medications (p = 0.0003), as well as the need for corticosteroids against the background of therapy from 34.6% to 0% (p = 0.00001). In 8% of cases, the result of treatment was good, in 69% satisfactory, in 23% unsatisfactory. In the control group, there were no changes in the severity of symptoms (p = 0.858). Also, in the control group, the need for medications remained unchanged and 14.3% of patients continued to use corticosteroids.After ASIT, there was a decrease in the level of IL-4 (p = 0.002), and a decrease in the ratio of IL-4/ IL-10 (p = 0.0063); at the same time, changes in the level of other cytokines (IL-10; IFNγ) were statistically insignificant (p > 0.05). Before treatment, the levels of IL-4/ IL-10 in both groups were comparable, and after treatment, the differences became statistically significant (p = 0.031). We did not get a statistically significant change in the level of IgG4 Amb a 1 or IgG4 Amb trifida. There was no correlation between the level of individual cytokines and the results of treatment. As a result of the conducted ASIT, positive clinical and immunological results were obtained. In most patients, the disease has acquired a controlled course. At the same time, the lack of excellent and low number of good results of ASIT is probably due to the intraspecific allergenic properties of ragweed.

Chemical Composition of Ambrosia trifida L. and Its Allelopathic Influence on Crops

Phytotoxic substances released by invasive plants have been reported to have anti-pathogen, anti-herbivore, and allelopathic activity. The aim of this study was to determine the allelopathic influence of the Ambrosia trifida L. on oxidative stress parameters (the lipid peroxidation process; reduced glutathione (GSH) content; and activity of antioxidant enzymes catalase (CAT), superoxide dismutase (SOD), and peroxidase (PX)) and phenolic compounds (total phenolic and tannin content) in maize (Zea mays L.), soybean (Glycine max L.), and sunflower (Helianthus annuus L.) crops to explore the effect of released allelochemicals through A. trifida root on crops. An analysis by HPLC confirmed the presence of protocatechuic acid, p-hydroxybenzoic acid, vanillic acid, and syringic acid as major components in the A. trifida. Based on the obtained results for oxidative stress parameters, it can be concluded that the sunflower was the most sensitive species to A. trifida allelochemicals among the tested crops. The other two crops tested showed a different sensitivity to A. trifida. The soybean did not show sensitivity, while the maize showed sensitivity only 10 days after the sowing.

The significance of biomass allocation to population growth of the invasive species Ambrosia artemisiifolia and Ambrosia trifida with different densities

Background Ambrosia artemisiifolia and Ambrosia trifida are globally distributed harmful and invasive weeds. High density clusters play an important role in their invasion. For these two species, the early settled populations are distributed at low densities, but they can rapidly achieve high population densities in a short period of time. However, their response to intraspecific competition to improve the fitness for rapid growth and maintenance of high population densities remains unclear. Therefore, to determine how these species form and maintain high population densities, individual biomass allocations patterns between different population densities (low and high), and plasticity during seedling, vegetative, breeding and mature stages were compared. In 2019, we harvested seeds at different population densities and compared them, and in 2020, we compared the number of regenerated plants across the two population densities. Results Most biomass was invested in the stems of both species. Ambrosia trifida had the highest stem biomass distribution, of up to 78%, and the phenotypic plasticity of the stem was the highest. Path analysis demonstrated that at low-density, total biomass was the biggest contributor to seed production, but stem and leaf biomass was the biggest contributors to high-density populations. The number of seeds produced per plant was high in low-density populations, while the seed number per unit area was huge in high-density populations. In the second year, the number of low-density populations increased significantly. A. artemisiifolia and A. trifida accounted for 75.6% and 68.4% of the mature populations, respectively. Conclusions High input to the stem is an important means to regulate the growth of the two species to cope with different densities. These two species can ensure reproductive success and produce appropriate seed numbers. Therefore, they can maintain a stable population over time and quickly form cluster advantages. In the management, early detection of both species and prevention of successful reproduction by chemical and mechanical means are necessary to stop cluster formation and spread.

Giant ragweed (Ambrosia trifida L.) in the territory of the Vladimir region

Relevance. The article provides data on the distribution of Ambrosia trifida L. in the Vladimir region, beyond its borders in Russia and in the world as a whole. A new place of growth of Ambrosia trifida L. was revealed in the city of Vladimir. The use of ragweed as a medicinal plant and its role in human life are described. Taking into account the fact that ragweed damages agriculture and is included in the list of quarantine objects, the work provides general and specific measures to combat it.

Ambrosia trifida (giant ragweed).

A. trifida is an annual herb native to temperate North America which is now present in a number of countries in Europe and Asia. The primary means of spread of A. trifida occurs accidentally as a contaminant of seed or agricultural equipment. This species readily colonises disturbed areas and is often one of the first plants to emerge in early spring. As a result it has an initial competitive advantage and can therefore behave as a dominant species throughout the entire growing season. A. trifida is a particular problem for cultivated agricultural and horticultural crops where it can significantly decrease yields. Like many species of Ambrosia, A. trifida produces pollen which is allergenic and can induce allergic rhinitis, fever, or dermatitis. A. trifida is extremely competitive and can also decrease native biodiversity. A. trifida is a declared noxious weed in its native range in California, Delaware, Illinois and New Jersey, USA and is also a quarantine weed in Poland and Russia.

Ambrosia trifida L.: Giant ragweed

Ambrosia trifida L. (AMBTR, fam. Asteraceae/Compositae) is native to North America. It was introduced accidentally to Europe at the end of the 19th century, with contaminated animal feed and seeds for planting. Today A. trifida is present in ruderal and agricultural habitats of many European countries (France, Italy, Germany, Russia, Spain, Romania, Slovakia, Czech Republic, Poland, Serbia, Bulgaria, etc.). Giant ragweed was detected for the first time in 1981 in Serbia (site Čoka). Over the following period it disappeared from this site, but was recorded again in 2006 in another site (central Bačka: Despotovo, Kucura, Savino Selo, Ravno Selo, Ruski Krstur). Currently in Serbia it has the status of an alien naturalized weed species. This summer annual plant can grow up to 6 m in height and exhibits a high degree of morphological and reproductive plasticity in response to encroachment by neighboring plants. It is present in disturbed habitats, such as agriculture fields, where it plays the role of the dominant species throughout the entire growing season. In most cases, leaves are opposite and always simple and generally have 3 distinct lobes but can also have as many as 5. It is a diploid (2n = 24), meso-hygrophilic species, preferring wet habitatse and can tolerate a wide variety of soil types. Also, this is a monoecious plant, where male and female flowers are separated on the same individual. A. trifida can hybridise with A. artemisiifolia (A. x helenae Rouleau, with 2n= 27 and 2n= 33), but this hybrid has been described as sterile. Compared to other summer annual species, A. trifida is among the first to emerge in early spring, at optimal temperatures from 10-24°C. Under optimal environmental conditions, giant ragweed produces around 1,800 (max 5,100) seeds plant-1. It flowers and bears fruit from July to September (October).The pollen of this species has allergenic potential. Additionally, in the USA and Canada giant ragweed populations have developed resistance to acetolactate synthase inhibitor herbicides and glyphosate. Giant ragweed can be a problematic weed in row crops (corn, soybean, sunflower, sugerbeet) and vegetables. In A. trifida the control measures should prevent further spread, and existing populations should be controlled by integrated weed management practices. Furthermore, A. trifida has a relatively low fecundity, a transient soil seedbank and a high percentage of non-viable or low-survivorship seeds, which are features that may have constrained its establishment and spread in the current environmental conditions in Serbia.

Presence Polygonum aviculare L. in the co-association of Ambrosia artemisiifolia L. and Ambrosia trifida L

Ambrosia artemisiifolia L. and Ambrosia trifida L. belong to allochthonous invasive weeds species. They cause great damage in colonized areas because they reduce the yield of agricultural crops, and also with their competitive abilities affect the suppression of other plants and thus affect the change of plant community. As Polygonum aviculare L. is one of the most common weeds on the European continent and a very common companion of rural and urban habitats, this study examined the impact of different ratios of A. artemisiifolia and A. trifida on the occurrence and abundance of P. aviculare. Presence P. aviculare was incereased in treatments with increasing A. trifida and decreased A. artemisiifolia/m2 .