نشریه گیاه پزشکی کاربردی
سال نهم شماره 1 (پیاپی 27، شهریور 1399)

Annually, 20-40% of agricultural products are destroyed by plant pests and pathogens. Plant disease management depends on pesticides and toxins that are potentially harmful to humans and the environment. Nanotechnology can offer benefits to pesticides, including reduced toxicity, improved reliability and durability and increased solubility in pesticides that are sparingly soluble in water. This paper examines two trends in the use of nanoparticles in controlling of phytopathogenic fungi: nanoparticles as protectors independently or as nanocarriers for fungicides. Despite the many potential benefits of nanoparticles, few nanoparticle-based products have been commercialized for agricultural applications. The lack of commercial applications can be explained by several factors, including the insufficient number of field studies and the lack of attention to the pest-host system. In other industries, nanotechnology has advanced rapidly, and it seems that the only way to continue advancing nanotechnology applications in agriculture is to understand the fundamental research questions and find scientific gaps for the rational and easy development of commercial nanoproducts.

In this study, the effect of Lixusincanescens on five sugar beet cultivars on five sugar beet cultivars (Shkoofa, Flores, SyRobustus, Silvetta and HilleshogMonatunno) in the year 2019-2020. Sampling was performed every 8days from early July to mid-September. At each date, the experimental sample of larval damage on the petiole, the number of eggs and larvae were counted, and at the end of the experiment, the yield and sugar titer were analyzed. The results showed, the significant difference between larval damage on the petiole, the number of eggs and larvae, yield and sugar grade result on the studied cultivars at the level of five times the probability of meaning. The lowest larval damage index on petiole was in Shokof (2.5) and Silvetta (2.5), and the highest in Monatunno (6.25) and Flores (5.5); The lowest number of eggs per plant in Shokofa (2.25) and Silvetta (3.25) and the highest in Monatunno (5.25) and Flores (5) The lowest number of larvae in Shokofa (1.75) and Silvetta (75/75) and the highest was observed in Monatunno (6.25) and Flores (5) cultivars. The highest density of eggs and larvae was observed in the sixth (August 11) and seventh (August 19) sampling. The highest yield and sugar content were observed in Shokofa and Silvetta cultivars and the lowest in Monatunno and SyRobustus cultivars. The results of this experiment can indicate that Shkoofa and Silota dances can be the best option in virus management due to the least amount of petiole damage, egg and larval density.

Pratylenchus loosi, the root lesion nematode, is the most important cause agent damaging tea crop in Iran and the world. This research was carried out with the aim of evaluating the effectiveness of  nematicide organic  amendments at infected level with a population above the injury threshold, four treatments in three replications with a randomized complete block design was done at Fashalem tea station in Gilan province. The results showed that in the infected environment with a population higher than the damage threshold, only the moisture content index, treatment of tobacco waste with 71.93% was the best treatment. In quantitative indices such as nematode population in soil and roots in infected P. loosi environments, neemarin(neem extract) treatment was most effective. There was no significant  difference observed between the treatments in green leaf index, but the increase in yield was observed in comparison with the control. The results of this study showed that the use of neemarin and tobacco waste can improve the quality indices in addition to reducing the population of nematode in soil and root and as an important biological factor in controlling nematodes.

Mollusca: Gastropoda (Mollusca: Gastropoda) are the main groups of invertebrates in various ecosystems that are known as pests of vegetable and summer crops as well as the intermediate host of a number of parasitic protozoan and worms. They are important in various fields of agriculture, medicine and veterinary medicine. Since there is no report on the species diversity of terrestrial snails in the west of Isfahan province, this study was conducted to study the biodiversity of terrestrial snails in the area and search for important species from different dimensions. For this purpose, the west of Isfahan province was divided into 5 regions (Faridan, Fereydoun Shahr, Chdegan, Khansar and Golpayegan). Then the samples collected from these stations were systematically and morphologically examined using valid identification keys up to the species level. The effect of environmental factors such as temperature and relative humidity on the distribution of species was also determined. According to the results, it was found that the optimum temperature for the collected snails was 19-15°C and the best relative humidity was 25-45%. Finally, based on the results, six species of four genera under two families were identified.

Agricultural pesticides may have detrimental effects on the environment and people consuming fresh products. Diazinon is a semi-systemic synthetic organophosphate insecticide, acaricide and nematicide, which is commonly used in agriculture because of its respiratory, contact, and digestive effects on a wide variety of rodent and sucking pests. Ultraviolet (UV) radiation is a form of electromagnetic energy with a short wavelength and a large amount of energy that is invisible to humans. UV's detrimental effects on all life on land and water, from bacteria to plants and vertebrates, are well known. In this analysis, the degradation of diazinon was evaluated using this radiation as a pesticide degrading agent. The experiment was carried out in two sprays on apple fruit and filter paper. Control samples were kept out of direct sunlight, while treatment samples were exposed to sunlight for 30, 60, 120 and 300 minutes. Each experiment was performed in three replications. According to the findings, the rate of diazinon degradation in the reactor was higher than that of sunlight. So that the highest degradation rate after 300 minutes with an average of 60% and 83% was observed in solar and reactor, respectively. Not only did UV radiation have a degrading effect on diazinon, but also it had a significant effect in combination with other factors.

Charcoal rot Macrophomina phaseolina is one of the most serious soil brone disease of melon with economic importance throughout the world. Due to the failure of crop rotation, clean seeds and chemical control, application of the resistance cultivars and varieties, regarding to their ability in infestation reduction and less tissue destruction would be efficient. This study was to study the reaction of 22 different varieties of melon in Varamin area, as one of the main source of melon production in Iran, under the greenhouse condition. The experiment was taken place with four replications under complete random block design. Feature examined were wet weight, dry weight and pathogenicity index which were monitored in one month. Results of the pathogenicity indices showed than four varities, Honey Dave, Tashkand, Isafahan and Hybrid Ananas T with the lowest infestation index (1-2.1) were recognized as resistant and three varieties of Haj Mashallahi, Samsouri Isfahan, Ananas Mina MN1 with the highest pathogenicity index (>4) were recognized as susceptible. The results of wet weight mean showed that both hajmashallahi and 7065 MA hybrid has the lowest (17.05 gr) and Ananas T Hybrid showed the highest (57.05 gr); for dry weight, Honey Pack hybrid has the highest (7.16 gr) and Daregaz Mashhad showed the lowest (1.99 gr) weight. The results revealed a highly significant difference among the cultuvars which would be a clue to use plant resistance as a key factor in melon charcoal rot management.