Presence of Late Blight of Potato in Uzbekistan and Measures to Combat It

The article discusses the development of a disease of cultivated plants, which was previously not typical for the conditions of Uzbekistan — late blight of potato. On the territory of the Tashkent region and the small educational economy of the Tashkent State Agrarian University in 2015–2020, the presence of late blight was noted on potato crops. The degree of development of the disease is 27.9–36.3%. A study was carried out on the use of new drugs: Antracol 70% and Banjo Forte. The best result in suppressing the disease was shown by the preparation Antracol 70% in the norm of application — 2.0 kg/ha, where 20 days after treatment the biological efficiency was 85.6%. The biological efficacy of Banjo Forte at a rate of 1.0 l/ha was 81.8% on the leaves, 84.1% on the shoots, and 1.5% and 1.0%, respectively, with the development of the disease.

Practice of Combating Potato (Solanum tuberosum L.) Disease in Azerbaijan on the Example of Phytophthora

Potatoes (Solanum tuberosum L.) are the fourth largest crop in the world after rice and corn. In Azerbaijan, the yield of potatoes per unit area is very low compared to other countries of the world. There are many factors that reduce crop productivity, among which diseases such as late blight of potato (Phytophthora infestans) play an important role. Therefore, the fight against this disease is very important. Late blight of potato can be controlled by the following control strategies: use of biological control agents, use of resistant varieties, crossbreeding, use of certified disease-free seeds, use of selective fungicides and agronomic practices such as destruction of cull heaps by freezing or deep burial, destruction sprouting voluntary potato plants in nearby fields during the season, killing infested plants to avoid spreading, shortening periods of leaf wetness and high canopy moisture through proper irrigation times, applying the recommended fungicide spraying program (program must be started before pathogen is detected).

Use of Digital Technologies to Improve Efficiency of Potato Production on Private Plots

In Russia, potato is the second economically important crop, which is widely cultivated not only on commercial fields, but also on numerous private plots, which produce a doubled potato yield comparing to agricultural companies. Nevertheless, during the last 30 years, the total potato production in Russia reduced by 40%. In the case of private plots, potato production reduced by even more then 50%. One of the possible reasons is that potato is difficult in cultivation and is susceptible for a number of diseases able to significantly reduce the yield quantity and quality. This paper describes a new approach to the crop protection based on the use of digital technologies to control the early and late blight of potato and to reduce the negative influence of excess fungicides on the human health and environment.

The Potency of Unassociated Trichoderma spp and the Fungicides Antagonistic of the Late Blight of Potato by Phytophthora infestans (Mont.) De-Bary

The potato (Solanum tuberosum) is one of the most important vegetable crops in the world, belonging to the family Solanaceae and is an important starchy food crop in both sub-tropical and temperate regions. Potato plants are subjected to attack by numerous diseases wherever the crop is grown. Among them, late blight of potato caused by Phytophthora infestans (Mont.) de-Bary is of major cause of concern in potato production at present. An experiment was conducted in the Department of Plant Pathology, College of Agriculture, Chandra Shekhar Azad University of Agriculture and Technology, Kanpur. The antifungal activity of different fungicides was evaluated in-vitro through the food poison technique. The experimental finding showed that radial growth of mycelium of Phytophthora infestans was inhibited by fungicides over control. At 100 ppm, the minimum radial growth of mycelium was found in Equation Pro treatment as 5.3, 8.2, 11.4, 14.2, 16.2, 18.4 and 22.6 mm over control against 12.3, 19.1, 26.1, 35.9, 42.5, 51.4 and 64.8 mm at 1, 2, 3, 4, 5, 6 and 7 days after inoculation respectively. Similarly, at 500 and 1000 ppm the minimum radial growth of mycelium was found in Equation Pro treatment. Efficacy of bio-control agents on the radial growth of Phytophthora infestans was evaluated using Dual Culture Methods. Among the different concentrations, 1000 ppm was found most effective than 100 and 500 ppm. Among the different bio-agents, Trichoderma harzianum able to reduced maximum radial mycelial growth of fungus showing 4.6, 8.8, 10.1, 13.2, 15.6, 19.3 and 23.5 mm against 12.3, 19.1, 26.1, 35.9, 42.5, 51.4 and 64.8 mm at 1, 2, 3, 4, 5, 6 and 7 days after inoculation, respectively.

EVALUATION OF TRICHODERMA HARZIANUM IN CONTROLLING LATE BLIGHT OF POTATO

Evaluation of Trichoderma harzianum in reducing mycelial growth of Phytophthora infestans as well as in controlling late blight of potato was done in Microbiology and Biocontrol laboratory and Net-house, Department of Plant Pathology, Bangladesh Agricultural University, Mymensingh during 2019-2020, Bangladesh. The experiment was conducted using popular potato variety Diamant and native variety Challisha. T. harzianum was evaluated in net-house and in-vitro condition. Fungicide Indofil M-45 (Mancozeb) was used as positive check for comparison. In Net-house experiment, T. harzianum increased plant height, number of tubers and fresh weight of tubers over control treatment for the both of the varieties of potato. T. harzianum on late blight of potato (var. Diamant) showed a significantly better management over control treatment. In comparison to non-treated control treatment, reduced infection of late blight was found in the T.harzianum treated plants, whereas increase disease severity was calculated in control treatment. After harvesting, tuber infection in T. harzianum treated plants was not observed. Percent inhibition of tuber infection over control was 100%. Indofil M-45 suppressed Disease severity but comparatively less effective than T. harzianum in the long run. In case of variety Challisha similar trend of results were observed. In dual culture assay, T. harzianum showed highest inhibitory effect in suppressing mycelial growth of P. infestans. T. harzianum showed 86.67% inhibition of mycelial growth of P. infestans over control. Thus, it can be concluded that T. harzianum is effective to control late blight of potato and sometimes comparable to chemical fungicide in net-house condition.

EffectorO: motif-independent prediction of effectors in oomycete genomes using machine learning and lineage specificity

Oomycete plant pathogens cause a wide variety of diseases, including late blight of potato, sudden oak death, and downy mildew of many plants. These pathogens are major contributors to losses in many food crops. Oomycetes secrete "effector" proteins to manipulate their hosts to the advantage of the pathogen. Plants have evolved to recognize effectors, resulting in an evolutionary cycle of defense and counter-defense in plant-microbe interactions. This selective pressure results in highly diverse effector sequences that can be difficult to computationally identify using sequence similarity. We developed a pipeline, EffectorO, that uses two complementary approaches to predict effectors in oomycete pathogen genomes: (1) a machine learning-based pipeline that predicts effector probability based on the biochemical properties of the N-terminal amino acid sequence of a protein and is trained on experimentally verified oomycete effectors and (2) a pipeline based on lineage-specificity to find proteins that are unique to one species or genus, a sign of evolutionary divergence due to adaptation to the host. We tested EffectorO on Bremia lactucae, which causes lettuce downy mildew, and Phytophthora infestans, which causes late blight of potato and tomato, and predicted many novel effector candidates, while still recovering the majority of known effector candidates. EffectorO will be useful for discovering novel families of oomycete effectors without relying on sequence similarity to known effectors.

Late blight of potato and its management through the application of different fungicides and organic amendments: a review

Late the blight of potato is a devastating and one of the economic diseases of potato and other plants belonging to family Solanaceae. Late blight, caused by Phytophthora infestans, is one of the most threatening pathogenic diseases which not only results in direct crop losses but also cause farmers to embrace huge monetary expenses for disease control and preventive measure. It was first reported during the Irish Potato Famine, leading to massive starvation in Ireland and other parts of Europe during the middle of 19th century. Phytopthora harms the foliar portion in the field and also the tuber in the storage that can result in complete crop failure in potato. The pathogen has distinct survival mechanisms and two life cycles infection processes. The development of a sexual spore known as oospore includes two types of pairs, A1 and A2. The spores are introduced to good plants by wind and rain. Different methods for prevention of crops from late blight has been developed and used worldwide. An integrated disease management strategy includes successful control of this disease. Cultural control, chemical management, and advanced disease management are the most effective interventions. Integration of late blight control in tropical regions with abundant fungal inoculants in most months of the year was also seen as one of the best choices in disease management. This paper reviews the significance of late blight of potato and controlling strategies adopted for minimizing yield losses incurred by this disease by the application of synthetic fungicides and different organic amendments.