Insect Pests Of Potato Research Articles

Rapid Screening of Colorado Potato Beetle Resistance Derived from Solanum okadae

Colorado potato beetle (CPB), Leptinotarsa decemlineata (Say) is a major insect pest of potato and development of resistant varieties is part of a strategy for management. Wild relatives of potato are resources for genetic improvement through breeding. Interspecies crosses to introgress CPB resistance will be facilitated with rapid and inexpensive selection methods. Solanum okadae is a novel source of feeding deterrence against the beetle and was associated with production of a naturally occurring leaf-specific lactone-containing metabolite in the foliage. The Baljet assay has been used for decades in pharmaceuticals for rapid screening of lactone-containing compounds. A modified Baljet assay was developed for potato foliar tissue to rapidly screen for lactone-containing compounds in plants from the field, greenhouse, and laboratory. Herein we report the screening of potato foliage for CPB resistance with a Baljet assay validated by CPB larval feeding studies. Foliage from wild accessions of S. okadae were tested using the Baljet assay and results showed that production of the leaf-specific lactones has a large range of variation in the species. In addition, tubers tested using the Baljet assay had negligible levels of lactone-containing metabolites, confirming leaf-specific production of lactones. This inexpensive method using leaf disk screening will allow potato breeders to quickly select for potential CPB resistant germplasms and advance the breeding of sustainable crops.

Heterologous expression of distinct insecticidal genes in potato cultivars encodes resistance against potato tuber moth, Phthorimaea operculella (Zeller) (Lepidoptera: Gelechiidae)

AbstractThe potato tuber moth, Phthorimaea operculella (Zeller), is a notorious insect pest of potato incurring substantial yield losses in the field as well as in storage. Chemical control is difficult to exercise due to the latent feeding of the caterpillars and their ability to develop resistance against insecticides. One of the essential components of efficient insect-resistant management is using two or more different insecticidal genes in transgenic crops to effectively avoid and delay the resistance development in insect pests. Two constructs, namely DS-1 (cry3A + SN-19 genes) and DS-2 (OCII + SN-19 genes) in pCAMBIA1301 binary vector, were developed and were transformed in potato cultivars (Agria and Lady Olympia) via Agrobacterium-mediated transformation. The molecular analysis confirmed gene integration and expression of the introduced genes in transgenic plants. The insecticidal effects of incorporated genes in transgenic plants were assessed against 1st, 2nd, 3rd, and 4th instar potato tuber moth (PTM) larvae. The transgenic plants endured significantly high mortalities (100%) of larval stages of PTM within 72 h. Our results show that these transgenic potato plants have the potential to control populations of PTM and are also useful tools in managing PTM that would ultimately reduce the dependency on conventional chemical pesticides with potentially less or minimal hazards. These lines can also serve as an excellent source of germplasm for potato breeding program.

Chromosome-level genome assembly of the Colorado potato beetle, Leptinotarsa decemlineata

The Colorado potato beetle (Leptinotarsa decemlineata) is one of the most notorious insect pests of potatoes globally. Here, we generated a high-quality chromosome-level genome assembly of L. decemlineata using a combination of the PacBio HiFi sequencing and Hi-C scaffolding technologies. The genome assembly (−1,008 Mb) is anchored to 18 chromosomes (17 + XO), with a scaffold N50 of 58.32 Mb. It contains 676 Mb repeat sequences and 29,606 protein-coding genes. The chromosome-level genome assembly of L. decemlineata provides in-depth knowledge and will be a helpful resource for the beetle and invasive biology research communities.

Farmers’ knowledge, perceptions and management of major insect pests of potato at Kavrepalanchok, Nepal

Out of the 13 municipalities in the district, four (Banepa, Panauti, Panchkhal and Mandandeupur) were chosen based on their higher production potential, and 25 households from each of the four municipalities were then randomly chosen, yielding a sample size of 100. We used both primary and secondary data collection methods. According to the findings, the disease is one of the top five primary issues facing farmers in the research area, with an index value of 0.818. Information level was divided into four categories: 0, 1, 2, 3 and 4, respectively, denoting lack of knowledge, knowledge about one insect pest, knowledge about two insect pests, knowledge about three insect pests, and knowledge about four or more insect pests. In the study area, the majority of farmers (33%) were found to be knowledgeable of 2 insect pests. The majority of farmers (67%) thought the potato tuber moth was the worst problem. The majority of farmers (42%) thought that insect pests only had a minimal impact on plant populations (about 40%). The majority of farmers (44%) believed that insect pests had only slightly harmed (40% area affected) their fields or stores. The majority of farmers (71%) said chemical methods were the most effective for controlling insect pests. The majority of farmers (50.6%) were found to apply the recommended dose of chemical pesticides for insect pest management. The majority of farmers (51%) thought that the proliferation of insect pests was on the decline.

Seasonal abundance of major insect pests of potato (Solanum tuberosum) and their natural enemies in Karnataka, India

It is essential to know the seasonal occurrences of various pests of potato along with their natural enemies so that timely management practices could be advised to farmers to avoid losses. Therefore, field studies on seasonal incidence of major insect pests of potato and their natural enemies were carried out at the All India Co-ordinated Research Project on Potato, Main Agricultural Research Station, University of Agricultural Sciences, Dharwad, India during Kharif 2016 and 2017; and at Hangaraki, a village near Dharwad during Rabi 2016-17 and 2017-18. The observations on the seasonal abundance of potato insects, mites, and their natural enemies were recorded at weekly intervals starting from 20 days after the emergence of the plant till harvest. These observations were made under unprotected conditions. During Kharif season, the sucking pests were active from July second week and continued up to harvesting of the crop and the maximum pest population was observed during August second week to September first week. The peak activity of the shoot borer, Leucinodes orbonalis Guenee was noticed during the 35th Meteorological Standard Week (MSW) (i.e., August). The maximum population of defoliator, Spodoptera litura (Fab.) was noticed during 34th MSW. The higher populations of coccinellid beetles and spiders were recorded during 35th MSW while chrysopid activity was maximum during 36th MSW (September). During Rabi season, the sucking pests were active from October second week and attained peak during the second and third week of November. The maximum activity of aphids and leafhoppers was noticed during the 46th and 47th MSW (November), respectively. The highest incidence of thrips was recorded during the 48th MSW. The peak population of whiteflies and mites was recorded during the 46th and 45th MSW, respectively. The peak activity defoliator and shoot borer were noticed during the 45th and 46th MSW, respectively. The chrysopid activity was maximum during 46th and 47th MSW.

Insights into the Use of Eco-Friendly Synergists in Resistance Management of Leptinotarsa decemlineata (Coleoptera: Chrysomelidae).

Simple SummaryThe discovery of insecticides requires time and has a high investment cost. However, injudicious use of insecticides has resulted in insect pest resistance and pest resurgence. These factors limit the market life of insecticides. To cope with this problem, synergists working as blockers of detoxification enzymes can provide a unique solution in resistance management. Owing to problems associated with chemical synergists, plant-based and RNAi-based synergists are much safer and easier to develop against insects. In fact, the Colorado potato beetle (CPB) has a unique detoxification mechanism due to its co-evolution with Solanaceous plants. This review is about how synergists can be used to deal with the resistance management of the CPB and will be helpful for researchers devising unique pest management strategies for other insect pests.The Colorado potato beetle (CPB), Leptinotarsa decemlineata (Say), is the most notorious insect pest of potato globally. Injudicious use of insecticides for management of this pest has resulted in resistance to all major groups of insecticides along with many human, animal health, and environmental concerns. Additionally, the input cost of insecticide development/discovery is markedly increasing because each year thousands of chemicals are produced and tested for their insecticidal properties, requiring billions of dollars. For the management of resistance in insect pests, synergists can play a pivotal role by reducing the application dose of most insecticides. These eco-friendly synergists can be classified into two types: plant-based synergists and RNAi-based synergists. The use of plant-based and RNAi-based synergists in resistance management of insect pests can give promising results with lesser environmental side effects. This review summarizes the resistance status of CPB and discusses the potential advantage of plant-based and RNAi-based synergists for CPB resistance management. It will motivate researchers to further investigate the techniques of using plant- and RNAi-based synergists in combination with insecticides.

Management of major insect pests of potato during rabi season using newer insecticide molecules

The field experiments were carried out in a randomized block design during rabi seasons of 2016-17 and 2017-18, to evaluate the effect of newer insecticide molecules against insect and mite pests of potato during rabi season in Karnataka, India. There were 10 treatments including an untreated check and replicated thrice. Kufri Pukhraj was used as a test variety in a plot size of 3 × 4 m with a spacing of 60 × 20 cm. Two sprays were taken up, the first being given 30 days after sowing and another 15 days later based on the economic threshold level of the pests. Among the insecticides evaluated, cyantraniliprole 10 OD @ 0.20 ml/l proved its excellence against shoot borer and defoliator by recording 65.27 and 72.69 per cent protection, respectively which was followed by spinosad 45 SC @ 0.20 ml/l (51.96 and 62.40%, respectively). Whereas in the case of sucking pests viz., aphid, leafhopper and whitefly, diafenthiuron 50 WP @ 1.00 g/l proved its superiority by documenting 78.00, 77.27 and 57.79 per cent protection, respectively. The highest percent protection over control against thrips was afforded by spinosad 45 SC @ 0.20 ml/l (67.54 %) followed by cyantraniliprole 10 OD @ 0.20 ml/l (58.62 %) and emamectin benzoate 5 SG @ 0.25 g/l (49.70 %). In respect of mites, the treatment with spiromesifen 22.9 SC @ 1.00 ml/l registered the highest protection of 70.38 per cent. The treatment cyantraniliprole 10 OD @ 0.20 ml/l recorded highest net returns of Rs. 2,65,897/ha with benefit-cost ratio of 7.47 followed by spinosad 45 SC @ 0.20 ml/l (Rs. 2,38,558/ha and 6.60) and emamectin benzoate 5 SG @ 0.25 g/l (Rs. 2,34,400/ha and 6.72).

Surveillance for potato tuber moth, Phthorimaea operculella Zeller (Lepidoptera: Gelichiidae) in Kolar and Chikkaballapur district of Karnataka

Potato tuber moth (PTM), Phthorimaea operculella Zeller has become one of the most serious insect pests of potato (Solanum tuberosum L.) around the world, including in India. Field studies were conducted against PTM in Rabi seasons during 2019-20 in four and two taluks of Kolar and Chikkaballapur districts of Karnataka, respectively to understand the extent of foliage damage and leaf mines. Mean per cent infestation of PTM and number of mined leaves per plant during Rabi season of survey were highest with 4.47% and 8.31 mined leaves in Kolar district and it was least in Chikkaballpur district (2.51% and 2.95), respectively. Number of mines per plant was observed lowest (5.09) in Kolar district compared to Chikkaballapur district with 5.24 mines per plant. The above damage parameters like per cent PTM infestation and number of mined leaves per plant were not differed significantly whereas number of mines per plant was significantly different in Chikkaballapur district. On the other hand, all the damage parameters were significantly differed in Kolar districts during the survey in Rabi season 2019-20. In recent years, the temperature has been steadily rising due to climate change, and it is predicted that the occurrence of the PTM will continue to increase in the future. Therefore, the development of control technologies and intensive monitoring will be necessary for stable potato production as well as potato post-harvest.

Dickeya dianthicola Is Not Vectored by Two Common Insect Pests of Potato

Dickeya dianthicola (Samson) is an important pathogen causing blackleg disease of potato. Previous work suggested that insects might vector species of Pectobacteriaceae between plants but no conclusive work has confirmed this. Green peach aphids (Myzus persicae Sulzer) and Colorado potato beetles (Leptinotarsa decemlineata Say) are aggressive potato pests and related to known vectors of several species of bacteria other than D. dianthicola. This study sought to determine whether these insects vector D. dianthicola for potato infection. Neither insect species showed olfactory discrimination based on the presence of infection in laboratory tests but beetles were repelled by uninfected foliage treated with 2,3-butanediol, a primary Dickeya metabolite. Beetle recruitment to plants was not affected by their infection status; however, aphids preferred uninfected foliage when conspecifics were present. In the laboratory, neither insect acquired or transmitted D. dianthicola through feeding. In the field, neither insect’s abundance was significantly correlated with disease spread. Overall, this study did not find indications that D. dianthicola is vectored by the tested insect species. Therefore, efforts to limit Dickeya spread should focus on sanitation, water management, and seed screening—not on the control of these insect species. [Formula: see text] Copyright © 2021 The Author(s). This is an open access article distributed under the CC BY-NC-ND 4.0 International license .

Management of Late Blight and Sucking Insect Pests of Potato with Application of Salicylic Acid and β-aminobutyric Acid under Greenhouse Conditions

Management of Late Blight and Sucking Insect Pests of Potato with Application of Salicylic Acid and β-aminobutyric Acid under Greenhouse Conditions

Origins, Divergence, and Contrasting Invasion History of the Sweet Potato Weevil Pests Cylas formicarius (Coleoptera: Brentidae) and Euscepes batatae (Coleoptera: Curculionidae) in the Asia-Pacific.

Cylas formicarius F. and Euscepes batatae Waterhouse are the most damaging sweet potato insect pests globally. Both weevils are thought to have invaded the Pacific alongside the movement of sweet potato (Ipomoea batatas (L.) Lam. Convolvulaceae), with C. formicarius having originated in India and E. batatae in Central or South America. Here we compare the genetic relationships between populations of the pests, primarily in the Asia-Pacific, to understand better their contemporary population structure and their historical movement relative to that of sweet potato. Cylas formicarius has divergent mitochondrial lineages that indicate a more complex biogeographic and invasive history than is presently assumed for this insect, suggesting it was widespread across the Asia-Pacific before the arrival of sweet potato. Cylas formicarius must have originally fed on Ipomoea species other than I. batatas but the identity of these species is presently unknown. Cylas formicarius was formerly designated as three species or subspecies and the genetic data presented here suggests that these designations should be reinvestigated. Euscepes batatae has very low genetic diversity which is consistent with its historical association with sweet potato and a recent introduction to the Asia-Pacific from the Americas. The distribution of E. batatae may be narrower than that of C. formicarius in the Asia-Pacific because it has relied relatively more on human-assisted movement. Consequently, E. batatae may become more widespread in the future. Investigating the invasion history of both species will help to understand the probability and nature of future invasions.

Transgenic potato lines expressing hairpin RNAi construct of molting-associated EcR gene exhibit enhanced resistance against Colorado potato beetle (Leptinotarsa decemlineata, Say).

Most of the commercialized insect resistant transgenic crops express cry gene(s) isolated from Bacillus thuringiensis; however, intensive cultivation of Bt crops over almost two decades has been questioned regarding its sustainability and durability in pest management. The present study focused on silencing of highly specific molting-associated Ecdysone receptor (EcR) gene of Colorado potato beetle (CPB) using RNA interference (RNAi) approach. The partial cDNA of EcR gene of CPB was amplified using specific primers in sense and anti-sense orientations, and cloned in pRNAi-GG vector flanked by an intronic sequence (pdk). Leaf and internodal explants of Agria and Lady Olympia potato cultivars were infected with Agrobacterium strain LBA4404 harboring constructs under the control of CaMV 35S promoter. Standard molecular analysis of primary transformants showed proper integration of T-DNA in plant genome. The transgenic plants of both cultivars were evaluated for their efficacy against first, second and third instar CPB larvae. The leaf biotoxicity assays revealed 15-80% of CPB mortality. A significantly lower fold-change (0.87-4.14×) in larval weight was observed in insects fed on transgenic plants compared to the ones fed on control plants (1.87-6.53×). Furthermore, CPB larvae fed on transgenic plants exhibited reduced EcR transcripts, indicating the functionality of dsRNA EcR in silencing EcR gene expression. This study is an excellent example of the integration of an alternative, effective and reliable method to cope with potato insect pests that incur significant losses to potato production in the world.

Seasonal dynamics of insect pests of potato under sub-tropical conditions of Punjab

Seasonal dynamics of insect pests of potato under sub-tropical conditions of Punjab

Molecular Characterization of Entomopathogenic Bacteria, Bacillus thuringiensis

The genetic variation of the new Bacillus thuringiensis isolate from soil and (Agrin) as a reference were evaluated by using random amplified polymorphic (RAPD-PCR) in order to distinguish between the isolates using random primers. It was noticed that; 1- Genetically, B.t .isolate is the closest to Agrin which is a commercial product of B.t., 2- Estimating such genetic variations among and between different strains or isolates of B.t may be of practical value for designing integrated pest management (IPM) programs. It is hoped that the results obtained from this study may safely and effectively help in managing this serious insect pest of potato in an integrated pest management (IPM) program.

Scenario, implications and prospects of climate change on potato (Solanum tuberosum) insect pests: A review

Potato (Solanum tuberosum L.) is a cool climate loving crop. Climatically, there is a short window in which potato has been fitted with appreciable use realized even 80 to 90 days old crop. Moreover a few other crops produce comparatively high yields of nutrients per unit area where land is scarce. That’s why potatoes are highly important formany marginal families of the country. High production levels and highly perishable sale practices enable farmers to be competitive despite the fact of high input cost, labour problem and forced gluts, still potato is an important cash crop and cultivated mainly as an irrigated winter cash crop. Among the various factors related to insect pestsand diseases, potato farmers are increasingly forced to face water stress change, changes in rainfall patterns and its intensity, frost and fog etc. These conditions are generally interpreted to be climate changes. Potato productionis highly dependent on climate and weather factors. All climate change projections are based on simulations andtherefore involve uncertainties. However, it is clear that climate change will not only affect the cultivation system butalso change the pressure of insect pests of potato. Disease free seed production may also be affected due to changes in the life cycles of aphids. Pests such as mite, potato tuber moth and cutworms may become more serious on potatocrop. At present most of the potato seed is grown in Northern plains under no or low aphid period in order to keep it virus free but change in climate, in certain regions, aphids/whiteflies will occurs in greater numbers, resulting threat particularly to virus free seed production. The precise impact of climate change on insects is somewhat uncertain because some changes may favours insects while other may inhibit the activity of few insects. The best economic strategy for farmers is to use IPM practices to monitor insect occurrence and their buildup on potato crop.

A survey of potato growers in Bangladesh: production and challenges

The study was conducted in the 20 upazila of 10 selected major potato growing districts of Bangladesh to find out the present potato cultivation status, challenges, diversity of pests and their risks management options among the farmers. The data were collected through interview of 500 potato farmers considering 25 potato farmers from each upazila. Infections of diseases were reported to be the major problems followed by lower market price of the produced potato. Other major problems faced during potato cultivation were insect pest attack and weed attack. The BARI Alu-7 (Diamant) was most susceptible potato variety to insect pests and diseases, whereas the Lal-pakhri was the least susceptible to pests. Most of the fields (98.50%) were infested by cutworm. Among these pests, cutworm and aphid were identified as major pests and caused high and moderate infestations respectively. Others were identified as minor pests of potato with low infestations. Potato tuber worm was found as the key pest in storage condition. Rat was reported as the most infesting vertebrate storage pests. Currently cutworm and aphid were more damaging insect pest of potato in field condition than previous infestation, and potato tuber worm was more damaging insect pest in storage. Insecticide spray is the most favorable pest control method among the potato growers. Only a little portion of farmers have knowledge about integrated pest management (IPM) practices. So, it is expected the proper awareness program and planning will be taken to handle such challenges.Res. Agric., Livest. Fish.5(2): 165-174, August 2018

Developmental stage affects the interaction of Steinernema carpocapsae and abamectin for the control of Phthorimaea operculella (Lepidoptera, Gelechidae)

Laboratory bioassays were conducted to evaluate the interactions between an entomopathogenic nematode (EPN), Steinernema carpocapsae (Nematoda: Steinernematidae), and the insecticide abamectin against the Potato tuber moth (PTM), Phthorimaea operculella, one of the key insect pests of potatoes (Solanum tuberosum). Steinernema carpocapsae was highly virulent against pre-pupae but significantly less virulent against pupae with respective LC50 values of 10.5 and 102.1 infective juvenile nematodes (IJs) per individual. Abamectin was similarly toxic to pre-pupae and pupae with respective LC50 values of 25.3 and 28.0 ppm. However, abamectin had detrimental effects on S. carpocapsae IJs causing up to 70% mortality when they were exposed at 1000 ppm for 24 h. PTM life stage had a strong effect on insect mortality when exposed to combinations of S. carpocapsae and abamectin. Against pre-pupae, combinations mostly had a synergistic effect on mortality with the exceptions being additive; against pupae, combinations mostly had an antagonistic effect on mortality with the exceptions being additive. The synergistic interaction in pre-pupae was the strongest and the antagonistic interaction in pupae the weakest when the combinations included the lowest abamectin rate (LC10) which can be explained by the more limited negative effect of the lower abamectin rate on the IJs. The synergistic interaction and the negative effect of higher abamectin rates on it were confirmed in a greenhouse experiment on potato plants. Combinations of abamectin and S. carpocapsae have potential for the control PTM and could help reduce to usage of synthetic insecticides in PTM management.

Lethal and Sublethal Effects of Mineral Oil on Potato Pests.

Mineral oil is a product used to reduce Potato Virus Y transmission in potato fields. However, there is little information available about other effects that oil may have on insect pests of potato. To better understand how mineral oil affects potato pests, we performed a series of experiments testing the effects of oil on mortality, behavior, and development of potato aphids, Macrosiphum euphorbiae (Thomas) (Hemiptera: Aphididae), green peach aphids, Myzus persicae (Sulzer) (Hemiptera: Aphididae), and Colorado potato beetles, Leptinotarsa decemlineata (Say) (Coleoptera: Chrysomelidae). All three species showed negative behavioral responses to oil-treated potato foliage. Oil treatment also increased aphid mortality. Colorado potato beetle mortality was not affected, but developing on oil-treated potato plants resulted in prolonged development and smaller adults. Additionally, oil acted synergistically with the entomopathogenic fungus Beauveria bassiana (Balsamo) Vuillemin (Hypocreales: Clavicipitaceae); Colorado potato beetle larvae were killed more rapidly when sprayed with both products compared with when sprayed with B. bassiana alone. Based on these results, mineral oil has the potential for expanded use in potato IPM programs.

Study on insect pest diversity and their risk management options in potato among extension personnels of Bangladesh

The study was conducted in the 20 upazila of 10 selected major potato growing districts of Bangladesh during the period from December 2014 to February 2015 to find out the present status and diversity of insect pests of potato, their risks and management options. The data were collected through interview of 60 field level officers of DAE including one UAO, one AEO and one SAAO. The data were analyzed using computer program SPSS 20 version. BARI Alu-7 (Diamant) variety and BARI Alu-8 (Cardinal) variety of potato were the most popular potato varieties used by the farmers for cultivation. The major sources of potato seeds used by the farmers for cultivation were the own produced seeds, BADC seeds, seed traders/dealers and neighboring farmers. Major problems faced during potato cultivation were diseases, insect pest attack and weed attack. The BARI Alu-7 (Diamant) and BARI Alu-8 were most susceptible potato varieties to insect pests and diseases, whereas the Lal-pakhri was the least susceptible to pests. Mostly (98.50%) the potato was infested in the field by cutworm, aphid, potato tuber worm, leaf miner, mole cricket, field cricket and leaf hoppers. Among these insect pests, cutworm and aphid were identified as major pests and caused damage with high and moderate infestation intensity, respectively. Others were identified as minor insect pests of potato caused damage with low infestation intensity. Mostly (73.50%) the potato tuber worm attacked potato tubers in storage and designated as a major insect pest of potato in storage and damaged potato with high infestation intensity. Currently cutworm and aphid were more damaging insect pest of potato in field condition than previous infestation, and potato tuber worm was more damaging insect pest in storage. Other important control options were application of flood irrigation and hand picking particularly for controlling cutworm, use of granular insecticides in furrows during planting of seed tubers. Most (95%) of the farmers received assistance and advices for controlling insect pests of potato from pesticide dealers. Other sources of services were DAE officials, neighboring farmers and NGO officials.

Potato tuberworm: impact and methods for control - mini review.

Abstract The potato tuberworm, Phthorimaea operculella Zeller, is one of the most economically significant insect pests of potato in both field and storage worldwide. The biology of the pest and various management strategies such as cultural practices, biological, and chemical control and other control methods are reviewed.