Potato Production Research Articles

Examining the effects of input allocation on potato production, production efficiency, and technical inefficiency in potato farming: Evidence from the Stochastic Frontier Model in search of sustainable farming practices

The research examined how input allocation affects potato production, efficiency, and technical inefficiency in potato farming. The results of the Stochastic Frontier Model explained that land area, manure, matador insecticide, and victory fungicide significantly enhanced potato production. The study also discovered that potato farms and farmer characteristics affected potato farming inefficiency, and the farmers did not achieve economic efficiency. Based on these findings, in promoting sustainable farming practices, the government should assist farmers in expanding potato farming, obtaining readily available manure, and receiving comprehensive guidance from agricultural extension workers on the proper use of insecticides and fungicides.

Seed tuber production of potato from stem cuttings, planting densities, and paclobutrazol concentrations

Rapid multiplication of potato seed using cuttings is a pivotal strategy for ensuring seed availability. This study aimed to elucidate the interactive effects of node number, paclobutrazol concentration, and planting density on seed potato and cutting productions. The study consisted of two experiments. The first experiment evaluated two genotypes (Granola and PKHT-6) with one or two nodes per cutting. The second experiment investigated planting density (one, three, or five plants per polybag) and paclobutrazol concentration (0, 15, 30, and 45 mg L-1). Notably, node number did not significantly influence cutting success, despite genotype-specific and interactive effects on vegetative parameters like plant height, stem diameter, leaf number, and root length. Planting density had no statistically significant impact on all vegetative parameters but demonstrably affected all production parameters. Conversely, paclobutrazol concentration significantly affected all vegetative parameters and influenced all production parameters except tuber weight per plant. From the results of this research, the use of single cutting is more recommended because it will obtain more plant material compared to two-node cuttings. Thus, in a more global context of potato development, this has the potential to increase the production of potato seeds from cuttings twice as much as the current seed production. The use of three plants/polybags is more recommended since it will produce more tuber but not different with five plants, and the use of paclobutrazol 15 mg L-1 is also recommended to increase the number of tubers. In this way, the production costs of G0 potato seeds can be reduced so that the availability of G0 potato seeds will be more guaranteed and affordable. Keywords: Granola; PKHT-6; rapid multiplication; tuber production

Development and Validation of Near-Infrared Reflectance Spectroscopy Prediction Modeling for the Rapid Estimation of Biochemical Traits in Potato.

Potato is a globally significant crop, crucial for food security and nutrition. Assessing vital nutritional traits is pivotal for enhancing nutritional value. However, traditional wet lab methods for the screening of large germplasms are time- and resource-intensive. To address this challenge, we used near-infrared reflectance spectroscopy (NIRS) for rapid trait estimation in diverse potato germplasms. It employs molecular absorption principles that use near-infrared sections of the electromagnetic spectrum for the precise and rapid determination of biochemical parameters and is non-destructive, enabling trait monitoring without sample compromise. We focused on modified partial least squares (MPLS)-based NIRS prediction models to assess eight key nutritional traits. Various mathematical treatments were executed by permutation and combinations for model calibration. The external validation prediction accuracy was based on the coefficient of determination (RSQexternal), the ratio of performance to deviation (RPD), and the low standard error of performance (SEP). Higher RSQexternal values of 0.937, 0.892, and 0.759 were obtained for protein, dry matter, and total phenols, respectively. Higher RPD values were found for protein (3.982), followed by dry matter (3.041) and total phenolics (2.000), which indicates the excellent predictability of the models. A paired t-test confirmed that the differences between laboratory and predicted values are non-significant. This study presents the first multi-trait NIRS prediction model for Indian potato germplasm. The developed NIRS model effectively predicted the remaining genotypes in this study, demonstrating its broad applicability. This work highlights the rapid screening potential of NIRS for potato germplasm, a valuable tool for identifying trait variations and refining breeding strategies, to ensure sustainable potato production in the face of climate change.

Effectiveness of PhosAgro NPK and Gumiton under cultivating potatoes in radioactive soil contamination conditions

Based on the results of three-year production tests, the effectiveness of the use of PhosAgro NPK complex fertilizer and a new organ-mineral complex based on Gumiton peat in potato cultivation technologies on radioactively contaminated sod-podzolic soils in the Novozybkovsky district of the Bryansk region was assessed. Soils differed in the level of fertility and in the density of137Cs pollution. It was shown that leaf treatment of 1 l/ha Gumiton plantings in the potato budding phase without fertilizer contributed to a 19 – 58% increase in tuber yield relative to control, depending on the year. The introduction of PhosAgro NPK fertilizer at a dose of 0.5 t/ha ensured an increase in potato yield by 22 – 42% relative to the control. The joint use of fertilizer and the drug increased the tuber harvest by 12 – 19%, compared to the PhosAgro NPK variant and by 37 – 68% relative to control. The multiplicity of the decrease in137Cs intake into tubers during the treatment of potato plantings with Gumiton was up to 6.4 times in relation to the control, with the combined use of the drug and fertilizer – up to 3.4 times in comparison with the PhosAgro NPK variant. The use of Gumiton and PhosAgro NPK guaranteed the production of potato tubers with137Cs content in accordance with SanPiN 2.3.2 standards. 2650-10. The use of the Gumiton organic-mineral complex and PhosAgro NPK complex fertilizer for production of regulatory clean potato products should be recommended on radioactively contaminated sod-podzolic soils of the Bryansk region.

Optimizing Irrigation and Fertilization to Simultaneously Improve Potato Tuber Yield, Water and Fertilizer Use Efficiency and Net Income in Northwest China

Irrigation, fertilization, and variety are important factors affecting potato production in northwest China. Field experiments (2021 and 2022) were performed to investigate the effects of irrigation and fertilization on the plant growth and soil microbial population of different potato varieties. Three irrigation levels were used, i.e., 100% ETc (W1), 80% ETc (W2), and 60% ETc (W3), with ETc standing for crop evapotranspiration. Three fertilization levels were used (N-P-K), i.e., 240-120-300 kg ha−1 (F1), 180-90-225 kg ha−1 (F2), and 120-60-150 kg ha−1 (F3). Three variety types were used, i.e., Feiurita (V1), Longshu 7 (V2), and Qingshu 9 (V3). These factors significantly influenced tuber yield (TY), net income (NI), and water productivity (WP). TY, NI, WP, total nitrogen accumulation (TNA), and nitrogen use efficiency (NUE) peaked at F2. Fertilization significantly impacted soil bacteria quantity (SBQ), fungi quantity (SFQ), and actinomycetes quantity (SAQ). TY, NI, SBQ, SFQ, and SAQ were highest at W2. Soil microbial population was strongly correlated with TY, NI, WP, TNA, and NUE. Comprehensively, this study suggests that irrigation that is varied from 248 to 266 mm, and fertilization (N-P-K) that is varied from 149.09-74.55-186.36 to 212.73-106.36-265.91 kg ha−1 can promote the potato industry’s sustainable development and provide important references for the optimal field management of potato cultivation in northwest China.

Potato productivity on the background of the entomopathogenic fungus <i>Metarhizium robertsii</i> application in production trials

For the first time in Western Siberia (Novosibirsk region), two-year production trials of an experimental prototype of a drug based on the entomopathogenic fungus Metarhizium robertsii have been conducted. Strain P-72 isolated from the dead larvae of Colorado potato beetle Leptinotarsa decemlineata Say from the collection of microorganisms of the Institute of Systematics and Ecology of Animals of the Siberian Branch of the Russian Academy of Sciences was used in this work. Species identification of the fungus was performed based on sequencing of the elongation factor gene region EF1α. The ability of the preparation to significantly increase the parameters of potato yield structure elements throughout the whole vegetation period was shown. A reliable increase in the number of surviving sprouts by 1.4 times, the number of stems and tubers by 1.5 times was found. The growth-stimulating effect of using the preparation based on entomopathogenic fungus was manifested in the increase of plant weight by the flowering phase. The average yield increase for two years amounted to 36.0% in the variant with application of M. robertsii significantly exceeding the productivity of potatoes in the control. The level of profitability of potato production with the use of entomopathogenic fungus M. robertsii increased to 92.0% (with 50.0% in the control) due to the increase in gross yield and improved quality of marketable products. Infestation of new harvest tubers with rhizoctoniose significantly decreased in the variant including treatment with entomopathogenic fungus: the number of tubers with sclerotia decreased 2.8 times compared to the control, which eventually led to an increase in the number of healthy tubers and a significant (2.5 times) decrease in the sclerotial index.

Response of selected nutrient elements in leaf tissues of sweet potato cv. 'Bophelo' to Nemafric-BL phytonematicide

Nemafric-BL phytonematicide is a potent plant-based nematicide which consistently suppress nematode population densities of root-knot (Meloidogyne species) nematodes on various crops, but with limited information on its effects on foliar nutrient elements in sweet potato. The objective of this study, therefore, was to investigate the effects of Nemafric-BL phytonematicide on accumulation of nutrient elements in leaf tissues of sweet potato cv. 'Bophelo' under greenhouse conditions in Limpopo Province, South Africa, during autumn (February-April) in 2021 and validated in 2022. The product was applied weekly at geometric concentrations, with mature leaves collected and prepared for analysis of nutrient elements at eight weeks. Seasonal interactions were not significant and therefore data were pooled (n = 70) and then subjected to the Curve-fitting Allelochemical Response Dose (CARD) algorithm computer model. Iron (R2 = 0.86), K (0.91) and Na (0.82) versus Nemafric-BL phytonematicide each exhibited negative quadratic relations, whereas Zn (0.83) versus the product exhibited positive quadratic relations. In all test elements, the CARD-generated biological indices illustrated that the accumulation of elements was highly sensitive to the concentration of Nemafric-BL phytonematicide. In conclusion, in sweet potato production, the application of Nemafric-BL phytonematicide can inhibit (Fe, K) and stimulate (Zn) the accumulation of certain elements in leaf tissues of sweet potato cv. ′Bophelo‵.

An Assessment of Some Mechanical Properties of Harvested Potato Tubers cv. Spunta

Mechanical properties of vegetables or crop materials play a noteworthy part in designing new related implements. These properties can be extracted from force–deformation curves. Several factors, such as soil preparation, irrigation, and pre- and post-harvest treatments influence them. The core objective of this investigation work was to analyze force–deformation curves obtained from compression, penetration, and shear tests of potatoes (Spunta cv.) produced with three tillage implements. The potatoes cv. Spunta were cultivated in loamy sand soil under the center-pivot irrigation system. The tillage implements used were a disc harrow plow, chisel plow, and moldboard plow. The trials were performed at a constant planting depth (15 cm) below the soil and a single plowing speed of 5.4 km/h. All data were expressed as an average of five replicates ± standard deviation. The force–deformation curves analysis showed that the modulus of elasticity for potatoes cv. Spunta ranged from 4.32 to 5.8 N/mm, the bioyield force ranged from 84.25 to 114.12 N, and rupture forces ranged from 100.90 to 139.78 N. Furthermore, the results showed that the average values of the elastic and plastic ranges were 3.0 and 2.1 mm, respectively. The mean value of hardness was 1671.53 N·mm. No significant differences were observed with respect to the two planting seasons, but tillage implements had a significant impact on the characteristics extracted from the compression tests. The mean of the maximum forces required to penetrate the potato during the penetration stage were 41.24 N, 44.86 N, and 47.16 N for potatoes produced with the disc harrow plow, chisel plow, and moldboard plow, respectively. Similarly, the means of the maximum forces required to cut the potato in the shear stage were 724.38 N, 761 N, and 773.43 N for the disc harrow plow, chisel plow, and moldboard plow, respectively. The force–deformation curves showed that additional information might be required to obtain a complete description of the potato quality necessary to harvest potatoes cv. Spunta using harvesting and handling equipment with reduced economic loss. An extensive study of the soil characteristics and the above-mentioned properties is also recommended. The results obtained about the mechanical characteristics of potatoes cv. Spunta can be useful in providing information that aids in designing potato harvesting machines and in potato products factories.

Natural Soil Amendments to Reduce Nitrate Leaching in Potato Production

Natural Soil Amendments to Reduce Nitrate Leaching in Potato Production

Antagonism and Synergism Characterize the Interactions between Four North American Potato Virus Y Strains

Potato virus Y (PVY) is one of the most important constraints to potato production worldwide. There is an increasing occurrence of recombinant PVY strains PVYNTN and PVYN-Wi and a decline in the incidence of the nonrecombinant PVYO. We hypothesized that this may be due to the ability of these recombinant strains to antagonize and/or outcompete PVYO in mixed infections. To determine this, we investigated interactions between PVYO and three recombinant PVY strains common in North America: PVYNTN, PVYN-Wi, and PVYN:O. Overall, our study showed that these interactions are tissue-dependent. Specifically, PVYNTN, the main causal agent of potato tuber necrotic ringspot disease (PTNRD), was found to be more adaptable than PVYO, especially in potato leaves due, at least in part, to the Ny gene that confers hypersensitive resistance (HR) to PVYO. Furthermore, PVYN-Wi was found to repress PVYO in potato tubers but act synergistically in potato leaves. The PVYO-induced foliage necrosis in cultivar ‘Ranger Russet’ was observed to be more severe in plants co-infected by PVYN-Wi and PVYN:O, respectively, resulting in plant death. Strikingly, this PVYO -induced necrosis was suppressed by PVYNTN in doubly infected plants. These interactions may, at least partially, explain the decreasing incidence of PVYO in United States potato production regions, especially given that many cultivars contain the Ny gene, which likely limits PVYO enabling PVYNTN and PVYN-Wi to outcompete. We also found that replication and cell-to-cell movement of these PVY strains in tubers at 4 °C was similar to levels at ambient temperature.

Potato E3 ubiquitin ligase StRFP1 positively regulates late blight resistance by degrading sugar transporters StSWEET10c and StSWEET11.

Potato (Solanum tuberosum) is the fourth largest food crop in the world. Late blight, caused by oomycete Phytophthora infestans, is the most devastating disease threatening potato production. Previous research has shown that StRFP1, a potato Arabidopsis Tóxicos en Levadura (ATL) family protein, positively regulates late blight resistance via its E3 ligase activity. However, the underlying mechanism is unknown. Here, we reveal that StRFP1 is associated with the plasma membrane (PM) and undergoes constitutive endocytic trafficking. Its PM localization is essential for inhibiting P. infestans colonization. Through in vivo and in vitro assays, we investigated that StRFP1 interacts with two sugar transporters StSWEET10c and StSWEET11 at the PM. Overexpression (OE) of StSWEET10c or StSWEET11 enhances P. infestans colonization. Both StSWEET10c and StSWEET11 exhibit sucrose transport ability in yeast, and OE of StSWEET10c leads to an increased sucrose content in the apoplastic fluid of potato leaves. StRFP1 ubiquitinates StSWEET10c and StSWEET11 to promote their degradation. We illustrate a novel mechanism by which a potato ATL protein enhances disease resistance by degrading susceptibility (S) factors, such as Sugars Will Eventually be Exported Transporters (SWEETs). This offers a potential strategy for improving disease resistance by utilizing host positive immune regulators to neutralize S factors.

The Value Chain and Sustainable Efficiency of Industrial Potatoes Through an Entrepreneur

This research was driven by the need for sustainable and efficient farming, productivity, and market expansion. This study mapped the industrial potato value chain, identified key stakeholders and their responsibilities, and assessed value chain linkages. This case study employed purposive sampling. The industrial potato value chain includes input suppliers, producers, processors, traders, and consumers, according to the research. Agricultural entrepreneurs are vital to the industrial potato value chain. He chose the Sharazur Plain, Kalar City, and Penjwin districts of Sulaimani Governorate in Iraq's Kurdistan Region for industrial potato production. Additionally, the entrepreneur has entered into agreements with Green Iraq Company as a processor, input supplier, and a chain supporter of the industrial potato value chain. The company has a significant role in enhancing producers to produce industrial potatoes, Lay's Chips is manufactured by a company in Sulaimani governorate/Bazian region. The study demonstrates that the implementation of contractual agreements may lead to a win-win situation for all parties involved. This reduces the farmer's risk by promoting cultivation and guaranteeing the firm has enough raw materials for processing. According to this study, universities, research centers, and agricultural departments have no role in the industrial potato value chain.

IDENTIFICATION OF POTATO LEAF DISEASES USING ARTIFICIAL NEURAL NETWORKS WITH EXTREME LEARNING MACHINE ALGORITHM

Potato plants have an important role in providing a source of carbohydrates for society. However, potato production is often threatened by various plant diseases, such as leaf disease, which can cause a decrease in yields. Identification of diseases on potato leaves is currently mostly done by farmers manually, so it is not always efficient and accurate. So the aim of this research is to identify diseases on potato leaves with artificial neural networks using the ELM (Extreme Learning Machine) approach and the GLCM (Gray Level Co-Occurrence Matrix) method for feature extraction. The GLCM approach functions to obtain texture features on objects by measuring how often certain pairs of pixel intensities appear together at various distances and directions in the image. Meanwhile, the ELM algorithm is used for image identification by adopting a one-time training method without iteration, which involves randomly determining weights and biases in hidden layers, thus allowing training to be carried out quickly and efficiently. Evaluation of the model by looking for the level of accuracy produces a value of 84.667%. The results show that the model developed is capable of accurate identification.

Mechanism Analysis of Antimicrobial Peptide NoPv1 Related to Potato Late Blight through a Computer-Aided Study.

Phytophthora infestans (Mont.) de Bary, the oomycotic pathogen responsible for potato late blight, is the most devastating disease of potato production. The primary pesticides used to control oomycosis are phenyl amide fungicides, which cause environmental pollution and toxic residues harmful to both human and animal health. To address this, an antimicrobial peptide, NoPv1, has been screened to target Plasmopara viticola cellulose synthase 2 (PvCesA2) to inhibit the growth of Phytophthora infestans (P. infestans). In this study, we employed AlphaFold2 to predict the three-dimensional structure of PvCesA2 along with NoPv peptides. Subsequently, utilizing computational methods, we dissected the interaction mechanism between PvCesA2 and these peptides. Based on this analysis, we performed a saturation mutation of NoPv1 and successfully obtained the double mutants DP1 and DP2 with a higher affinity for PvCesA2. Meanwhile, dynamics simulations revealed that both DP1 and DP2 utilize a mechanism akin to the barrel-stave model for penetrating the cell membrane. Furthermore, the predicted results showed that the antimicrobial activity of DP1 was superior to that of NoPv1 without being toxic to human cells. These findings may offer insights for advancing the development of eco-friendly pesticides targeting various oomycete diseases, including late blight.

Influence of weather conditions in Central Polissia, Ukraine, on the expression of quality indicators in potato cultivars of different maturity groups

For Ukrainians, potatoes are a key foodstuff and the most important strategic crop in the vegetable segment, and therefore it is vital to investigate the quality characteristics of potato tubers. The purpose of this study was to investigate the influence of various meteorological factors on the taste and starch content of tubers of different potato cultivars. The study employed laboratory, analytical, mathematical, and statistical methods. Both positive and negative correlation between starch content in tubers, taste, average monthly temperature, and precipitation were found in cultivars of different ripeness groups. For some potato cultivars, the positive effect on the starch content in tubers was due to the synergistic interaction of temperatures in August and precipitation in July, while for other cultivars this effect was determined by temperature and precipitation in August. It was found that an increase in temperature in August contributed to the improvement of the taste characteristics of early-ripening cultivars, while for middle early and mid-ripening genotypes, increased temperatures in June and August were key factors, and middle-late cultivars responded to increased precipitation in August. For each of the 19 cultivars studied, periods with a positive effect of average monthly temperature and precipitation on the improvement of taste were identified. The cluster analysis helped to identify potato cultivars with high starch content – Lietana, Opillia, Vzirets, and Oleksandryt, with high taste qualities – Lietana, Mezhyrichka 11, Vzirets, Avanhard, Partner, Oleksandryt, Fanatka, Rostavytsia, and Opillia. The findings of this study can serve as a scientific basis for the formulation of policies aimed at mitigating the effects of climate change and adapting existing cultivars to support sustainable potato production in a particular region and creating new plastic potato genotypes with sustainable quality characteristics

Assessing heat tolerance in potatoes: Responses to stressful Texas field locations and controlled contrasting greenhouse conditions.

In recent years, heat stress has affected potato production more frequently, resulting in lower marketable yields and reduced tuber quality. In order to develop heat-tolerant potatoes, it is necessary to select under heat-stress conditions and consider traits affected by heat stress. The Texas A&M Potato Breeding Program has selected potatoes under high-temperature stress for several decades. Ten potato cultivars, representing heat tolerant and sensitive clones based on past performance in Texas, were included in field trials for three years at the two main locations used by the Texas Breeding Program (Dalhart and Springlake, TX) to assess if the Texas field locations are suitable for heat tolerance screening. Both locations were confirmed as appropriate for heat stress screening. However, Springlake was a more stressful location since it had significantly lower yields of marketable tubers and increased percentages of tuber defects. Planting time did not have a significant effect at the most stressful location. The same ten potato clones were included in greenhouse experiments with contrasting temperatures (normal versus heat stress). There was confirmation that heat stress conditions resulted in significantly lower marketable yields, specific gravity, dormancy, and significantly higher percentages of tuber defects; however, significant differences existed between potato clones. Under heat stress conditions, Russet Burbank had a high percent of tubers with external defects, whereas Atlantic showed the highest percentage of internal defects (mainly internal heat necrosis). Vanguard Russet produced the highest marketable yield while maintaining a low percentage of external and internal defects. Russet Burbank and Atlantic were heat-sensitive controls for external and internal tuber defects, respectively. In contrast, Vanguard Russet can be used as a reliable heat-tolerant control. Including appropriate controls in heat stress studies will help identify clones with heat tolerance.

Dynamics of Potato Virus Y Infection Pressure and Strain Composition in the San Luis Valley, Colorado.

The San Luis Valley (SLV), Colorado, is the second-largest fresh-potato-growing region in the United States, which accounts for about 95% of the total production in Colorado. Potato virus Y (PVY) is the leading cause of seed potato rejection in the SLV, which has caused a constant decline in seed potato production over the past two decades. To help potato growers control PVY, we monitored the dynamics of PVY infection pressure over the growing seasons of 2022 and 2023 (May through August) using tobacco bait plants exposed to field infection weekly. PVY infection dynamics were slightly different between the two seasons, but July and August had the highest infection in both years. The first PVY infection was detected in the second half of June, which coincides with the emergence of potato crops in the valley. PVY infection increased toward the beginning of August and declined toward the end of the season. Three PVY strains were identified in tobacco bait plants and potato fields, namely PVYO, PVYN-Wi, and PVYNTN. Unlike other producing areas of the United States, PVYO is still the major strain infecting potato crops in Colorado, comprising ∼40% of total PVY strain composition. This could be explained by the prevalence of the potato cultivar Russet Norkotah that lacks any identified N genes, including the Nytbr that controls PVYO, which imposes no negative selection against this strain. The current study demonstrated the usefulness of bait plants to understand PVY epidemiology and develop more targeted control practices of PVY.

Effects of Seed Tuber Size of Potato Varieties on Fungicide Spray Regime, Weed Infestation and Net Farm Income in Potato Production

Effects of Seed Tuber Size of Potato Varieties on Fungicide Spray Regime, Weed Infestation and Net Farm Income in Potato Production

Perspective: could Ethiopian potatoes contribute to environmental sustainability, the Ethiopian economy, and human health?

Environmental data are rapidly accruing on the unsustainability of diets based on animal products, such as dairy and meats. Shifting to alternative sources of protein is inevitable given an increase in the projected global population and protein demand. Left unchecked, a collision between food security and sustainability is imminent. Potatoes could be the strategic food and cash crop to harmonize food security and sustainability worldwide. Recently, there has been a growing interest in extracting proteins from the byproduct of the potato starch industry known as potato fruit juice. These proteins are garnering attention due to their nutritional value, characterized by a well-balanced amino acid profile, as well as their functional properties including emulsifying, foaming, and gelling capabilities. Moreover, these proteins are considered to be less allergenic than some other protein sources. Extracting potato protein, which is sourced as a byproduct, reduces food loss and waste, thereby eliminating pathogenic microorganisms from the environment and mitigating greenhouse gas emissions. Ethiopia is a major potato producer in East Africa. Potatoes help the country increase household income, ensure food security and revenue generation, and produce starch. However, Ethiopia’s potato starch industry has not yet begun protein extraction, despite the vital role of the proteins and the country’s huge cultivation potential. Furthermore, the global potato protein market is experiencing significant growth. This information urgently calls for innovative approaches to assess the impact of extracting protein from potatoes produced in Ethiopia. Therefore, this perspective article has two main objectives. First, to scan the extent of potato production in Ethiopia in relation to environmental sustainability and the economy. Second, to provide prospects on the impact of extracting protein isolate from potatoes produced in Ethiopia on environmental sustainability, Ethiopia’s economy, and human health.

Understanding the Temporal Dynamics of Invasive Late Blight Populations in India for Improved Management Practices.

The microbial oomycete pathogen Phytophthora infestans causes severe epidemics of potato late blight in crops globally. Disease management benefits from an understanding of the diversity of pathogen populations. In this study, we explore the dynamics of P. infestans populations in the late blight-potato agro-ecosystem across the Indian subcontinent. Investigations of the macroecological observations at the field level and microbial ecological principles provided insights into future pathogen behavior. We use a comprehensive simple sequence repeat allele dataset to demonstrate that an invasive clonal lineage called EU_13_A2 has dominated populations over 14 years across India, Bangladesh, and Pakistan. Increasing levels of subclonal variation were tracked over time and space, and, for the first time, populations in Asia were also compared with the source populations from Europe. Within India, a regional pathogen population structure was observed with evidence for local migration, cross-border movement between surrounding countries, and introductions via imports. There was also evidence of genetic drift and between-season transmission of more strongly pathogenic subclones with a complete displacement of some subclonal types. The limited introduction of novel genotypes and the use of resistant potato cultivars could contribute to the dominance of the 13_A2 lineage. The insights will contribute to the management of the pathogen in these key global potato production regions.