LV EN RU DE FR

Agricultural Entomology and Plant Pathology

Course developers

Course abstract

Objectives of the course are to study various harmful and economically beneficial invertebrates (arthropods, molluscs, roundworms), their biology and ecology in agriculture. Also, methods for investigation and monitoring of economically important invertebrates and how agro-ecological factors affect populations of pests and beneficial invertebrates inhabiting various agroecosystems.
Students understand the concept “plant diseases” and learn about the causes and causal agents of diseases (fungi, viruses, bacteria). Students comprehend the regularities of disease development and their harmfulness and are acquainted with the most important plant diseases, their causal agents, disease symptoms and life cycles.

Learning outcomes and their assessment

Entomology
Students have knowledge about the systematics, morphology, reproduction and development, diversity of insects and other invertebrates relevant in agriculture – test 1.
Knowledge about insect research methods, competent in the basics of insect ecology, understands the impact of various agronomic activities on the populations of crop pests and beneficial invertebrates – test 2.
Knows how to identify crop pests and the damage they cause to plants, knows how to describe the biology, ecology and economic importance of pests and beneficial insects – test 3.

Phytopathology
Students obtain the knowledge about the reasons of plant diseases and know the classification of diseases and the peculiarities of diseases caused by bacteria and viruses – 1st test.
Students comprehend the concept of resistance, understand the peculiarities of disease development and know the methods of disease assessment and diagnostics. They can characterise the most important phyla of the kingdoms Fungi, Chromista and Protozoa – 2nd test.
Students can diagnose diseases and identify their causal agents till genus level – laboratory exercises and a practical test. Students know the most important plant diseases, can evaluate their harmfulness and integrate the knowledge about disease life cycles with the factors promoting their development, with agronomic practice and with possibilities of disease control – 3rd and 4th test.

Course Content(Calendar)

Full time
Lectures 32+32
Entomology
1. Entomology science. Morphology of insects. Body structure. Reproduction and individual development. Peculiarities of eggs’ laying, types of metamorphosis (holometaboly and hemimetaboly). Moulting. Types of larvae and pupas. Generation, change of generation, diapause. (2 h).
2. Classification and diversity of insects. Main orders of hexapods: springtails (Collembola), bristletails (Thysanura), mayflies (Ephemeroptera), dragonflies (Odonata), cockroaches (Blattodea), orthopterans (Orthoptera), earwigs (Dermaptera), thrips (Thysanoptera), bugs (Hemiptera), beetles (Coleoptera), net-winged insects (Neuroptera), caddisflies (Trichoptera), butterflies and moths (Lepidoptera), dipterans (Diptera), fleas (Siphanoptera), hymenopterans (Hymenoptera) and others. (2 h).
3. Classification and diversity of other invertebrates important in agriculture. Roundworms (Nematoda), terrestrial molluscs: snails and slugs (Gastropoda: Arionidae, Agriolimacidae, Helicidae etc.). Spiders and mites (Arachnida: Araneae, Acari) and other chelicerates. (4 h).
4. Polyphagous pests. European mole cricket (Gryllotalpa gryllotalpa), click beetles (Agriotes spp.), white grub cockchafer (Melolontha melolontha), turnip moth (Agrotis segetum), two-spotted spider mite (Tetranychus urticae) and others. (1 h).
5. Pests of cereals. Rye thrip (Limothrips denticornis), grains aphid (Sitobion avenae), bird cherry-oat aphid (Rhopalosiphon padi), cereal leaf beetles (Oulema spp.), barley flea beetle (Phyllotreta vittula), hessian fly (Mayetiola destructor) etc. (1 h).
6. Pests of legumes. Clover seed weevil (Protapion apricans), pea thrip (Kakothrips robustus), pea aphid (Acyrthosiphon pisum), pea beetle (Bruchus pisorum), pea moth (Laspeyresia nigricana), black bean aphid (Aphis fabae), bean seed beetle (Bruchus rufimanus) etc. (2 h).
7. Pests of crucifers. Common pollen beetle (Brassicogethes aeneus), large striped flea beetle (Phyllotreta nemorum), cabbage stem weevil (Ceutorhynchus pallidactylus), cabbage seed weevil (Ceutorhynchus obstrictus), diamondback moth (Plutella xylostella), cabbage moth (Barathra brassicae), large white (Pieris brassicae), small white (Pieris rapae), cabbage root fly (Delia radicum), brassica pod midge (Dasineura brassicae), turnip sawfly (Athalia rosae) etc. (2 h).
8. Pests of vegetables. mangold flea beetle (Chaetocnema concinna), beet leafminer (Pegomya hyoscyami), sugar beet nematode (Heterodera schachtii), carrot psyllid (Trioza apicalis), carrot fly (Psila rosae), mite Rhizoglyphus echinopus, lesser bulb fly (Eumerus strigatus), onion fly (Delia antiqua), tobacco thrips (Thryps tabaci), seedcorn maggot (Delia platura), alder buckthorn-willowherb aphid (Aphis frangulae), green peach aphid (Myzus persicae), buckthorn-potato aphid (Aphis nasturtii), Colorado potato beetle (Leptinotarsa decemlineata), potato cyst nematodes (Globodera spp.) etc. (1.5 h).
9. Pests of flax. Large flax flea beetle (Aphthona euphorbiae), tortrix moth Clepsis pallidana, tortrix moth Cochylis epilinana etc. (0.5 h).
10. Pests of fruit-trees. European red mite (Panonychus ulmi), apple blossom weevil (Anthonomus pomorum), apple ermine (Yponomeuta malinellus), apple fruit moth (Argyresthia conjugella), codling moth (Cydia pomonella), lackey moth (Malacosoma neustria), winter moth (Operophthera brumata), apple sawfly (Hoplocampa testudinea), pear bud mite (Eriophyes pyri), plum rust mite (Aculus fockeui), mealy plum aphid (Hyalopterus pruni), plum fruit moth (Grapholita funebrana), yellow prune tree sawfly (Hoplocampa flava), black cherry aphid (Myzus cerasi), cherry slug (Caliroa limacina), European cherry fruit fly (Rhagoletis cerasi) etc. (2 h).
11. Pests of berry crops. Strawberry foliar nematode (Aphelenchoides fragariae), cyclamen mite (Tarsonemus pallidus), strawberry blossom weevil (Anthonomus rubi), raspberry beetle (Byturus tomentosus), raspberry cane midge (Resseliella theobaldi), Cecidophyopsis spp. mites, magpie moth (Abraxas grossulariata), currant clearwing (Synanthedon tipuliformis), common gooseberry sawfly (Nematus ribesii), red gall midge (Resseliella ribis), blueberry gall midge (Dasineura oxycoccana) etc. (2 h).
12. Pests of greenhouses. Palm thrips (Parthenothrips dracaenae), greenhouse whitefly (Trialeurodes vaporariorum) etc. (0.5 h).
13. Storage pests. Flour mite (Acarus siro), biscuit beetle (Stegobium paniceum), mealworm beetle (Tenebrio molitor), confused flour beetle (Tribolium confusum), granary weevil (Sitophilus granarius), moth Nemapogon variatella, Mediterranean flour moth (Ephestia kuehniella), meal moth (Pyralis farinalis) etc. (0.5 h).
14. Pests of ornamental plants. Rose aphid (Macrosiphum rosae), rose sawflies (Tenthredinidae spp.), gladiolus thrips (Thrips simplex), scarlet lily beetle (Lilioceris lilii), large narcissus fly (Merodon equestris), rhododendron lace bug (Stephanitis rhododendri), black vine weevil (Otiorhynchus sulcatus), privet leafminer (Gracillaria syringella), viburnum aphid (Aphis viburni), viburnum leaf beetle (Pyrrhalta viburni) etc. (1 h).
15. Beneficial invertebrates. Ladybird beetles (Coccinellidae), ground beetles (Carabidae), rove beetles (Staphylinidae), hoverflies (Syrphidae), robber flies (Asilidae), aphid midge (Aphidoletes aphidimyza), ichneumon wasps and braconids (Ichneumonidae, Braconidae), trichogrammatids (Trichogrammatidae), social bees (Apidae), social wasps (Vespidae), sand wasps (Sphecidae), predatory mites (Hypoaspis aculeifer, Amblyseius cucumeris, Phytoseiulus persimilis etc.) etc. (2 h).
16. Ecology of insects. Ecological systems (habitat, biocenosis and agrocenosis). Abiotic (soil, climate etc.), biotic (food resources, interspecific interactions) and anthropogenic factors influencing insects in agrocenoses. Reproduction potential of insects. Ecological valence, eurybiont and stenobiont species. Mimicry and aposematism. (2 h).
17. Methods for insects’ monitoring and investigations. Qualitative, quantitative and semi-quantitative methods, short characterization of them. Equipment necessary for insects’ monitoring and investigations. (2 h).
18. Control of populations of harmful invertebrates. Activities of integrated pest management influencing populations of harmful and beneficial invertebrates. Preventive and corrective activities for plant protection. Economical threshold. (4 h).

Phytopathology
1. The concept “plant diseases” and disease causal agents. Classification of diseases. Parasitism and its types (2h).
2. Fungi as important causal agents of plant diseases. Causal agents of diseases from the kingdoms Protozoa and Chromista (10h).
3. Bacteria and viruses as important causal agents of plant diseases (2h).
4. Phylogenetical specialisation, pathogenicity, aggressiveness, resistance, and tolerance (1h)
5. Life cycles of diseases; factors that influence the development of epidemics. Methods of disease assessment and diagnostics (2h).
6. Diseases of cereals and pulses (4h).
7. Diseases of oilseed rape (2h).
8. Diseases of potatoes (2h).
9. Diseases of vegetables (4h).
10. Diseases of fruit trees and berries (4h).

Laboratory works – 16+16
Entomology
1.Morphology of insects. (1 h).
2.Individual development of insects. (1 h).
3.Classification of insects. Springtails, orthopterans, earwigs and cockroaches. (1 h).
4.Thrips and bugs. (1 h).
5.Beetles. (1 h).
6.Butterflies. (1 h).
7.Net-winged insects, flies and hymenopterans. (1 h).
8.Polyphagous pests. (1 h).
9.Pests of cereals. (1 h).
10.Pests of legumes. (1 h).
11.Pests of crucifers. (1 h).
12.Pests of vegetables. (1 h).
13.Pests of fruit-trees. (1 h).
14.Pests of berry crops. (1 h).
15.Storage pests and pests of ornamental plants. (1 h).
16.Beneficial insects. (1 h).

Phytopathology
1. The concept “plant diseases” and disease causal agents. Classification of diseases. (1 h).
2. The composition and reproduction of Fungi (1 h).
3. Fungi from Ascomycota, morphology of fruiting bodies, important orders (1 h).
4. The order Erysiphales, disease symptoms, life cycle (1 h).
5. Traits of asexual reproduction of fungi from the phyla Ascomycota and Basidiomycota, disease symptoms (1 h).
6. Fungi from Basidiomycota, important orders. The order Pucciniales, disease symptoms, life cycle (1h).
7. The order Ustilaginales, disease symptoms, life cycle (1h).
8. Plant pathogens from Chromista un Protozoa (1h)
9. Practical test (2 h)
10. Diseases of cereals (1h)
11. Diseases of oilseed rape and pulses(1h).
12. Diseases of potatoes (1h).
13. Diseases of vegetables (1h).
14. Diseases of fruit trees (1h)
15. Diseases of berries (1h)


Part time
Lectures-16+16
Entomology
1. Science of entomology. Insect morphology. Body segmentation. (1 h)
2. Reproduction and individual development. Types of metamorphosis (complete and incomplete). Types of larvae and pupae. Classification and diversity of insects. (1 h)
3. Biology, ecology and harmfulness of various crop pests. (6 h)
4. Beneficial invertebrates. Ladybird beetles (Coccinellidae), ground beetles (Carabidae), rove beetles (Staphylinidae), hoverflies (Syrphidae), robber flies (Asilidae), aphid midge (Aphidoletes aphidimyza), ichneumon wasps and braconids (Ichneumonidae, Braconidae), trichogrammatids (Trichogrammatidae), social bees (Apidae), social wasps (Vespidae), sand wasps (Sphecidae), predatory mites (Hypoaspis aculeifer, Amblyseius cucumeris, Phytoseiulus persimilis etc.) etc. (1 h)
5. Ecology of insects. Ecological systems (habitat, biocenosis and agrocenosis). Abiotic (soil, climate etc.), biotic (food resources, interspecific interactions) and anthropogenic factors influencing insects in agrocenoses. Reproduction potential of insects. Ecological valence, eurybiont and stenobiont species. Mimicry and aposematism. (2h)
6. Methods for insects’ monitoring and investigations. Qualitative, quantitative and semi-quantitative methods, short characterization of them. Equipment necessary for insects’ monitoring and investigations. (1 h)
7. Control of populations of harmful invertebrates. Activities of integrated pest management influencing populations of harmful and beneficial invertebrates. Preventive and corrective activities for plant protection. Economical threshold. (4h)

Phytopathology
1. The concept “plant diseases” and disease causal agents. Classification of diseases. (1h)
2. Fungi as important causal agents of plant diseases. Causal agents of diseases from the kingdoms Protozoa and Chromista (2h).
3. Bacteria and viruses as important causal agents of plant diseases (2h)
4. Life cycles of diseases; factors that influence the development of epidemics. Methods of disease assessment and diagnostics (2h)
5. Diseases of cereals and pulses (2h).
6. Diseases of oilseed rape (2h).
7. Diseases of potatoes (1h).
8. Diseases of vegetables (2h).
9. Diseases of fruit trees and berries (2h)


Laboratory works – 8+8
Entomology
1. Polyphagous and cereal pests (1h).
2. Pests of pulses (1h).
3. Pests of cruciferous plants (1h).
4. Vegetable pests (1h).
5. Pests of fruit trees (1h).
6. Pests of berry crops (1h).
7. Pests of storage houses and ornamental plants (1h).
8. Beneficial insects (1h).

Phytopathology
1. The concept “plant diseases” and disease causal agents. Classification of diseases. (1 h).
2. The composition and reproduction of Fungi (1 h).
3. The order Erysiphales, disease symptoms, life cycle (1 h).
4. Traits of asexual reproduction of fungi from the phyla Ascomycota and Basidiomycota, disease symptoms (1 h).
5. Fungi from Basidiomycota, important orders. The order Pucciniales, disease symptoms, life cycle (1h).
6. The order Ustilaginales, disease symptoms, life cycle (1h).
7. Plant pathogens from Chromista un Protozoa (1h)
8. Practical test (1 h)

Requirements for awarding credit points

1. All laboratory works are accomplished.
2. Written test (test No. 1) on morphology, reproduction, individual development and diversity of insects, spiders, terrestrial molluscs and roundworms is successfully passed (grade is at least 4).
3. Written test (test No. 2) on ecology and monitoring methods of insects and on activities of integrated pest management is successfully passed (grade is at least 4).
4. Oral test (test No. 3) on identification and characterization of economically important invertebrates’ species passed successfully (grade is at least 4); only students who accomplished all laboratory works and passed test No. 1 are allowed to do the test No. 3.
5. Written test about concept “plant diseases” and disease causal agents. Classification of diseases. Bacteria and viruses as important causal agents of plant diseases (grade is at least 4).
6. Written test about resistance, life cycles of diseases; factors that influence the development of epidemics. Methods of disease assessment and diagnostics. Causal agents of diseases from the kingdoms Fungi, Protozoa and Chromista (grade is at least 4).
7. Written test about most important diseases observed in cereals, oilseed rape and faba beans Chromista (grade is at least 4).
8. Written test about most important diseases observed in potato, vegetables, fruit trees and berries (grade is at least 4).
9. Practical test in phytopathology laboratory exercises about disease symptoms recognition and determination of disease causal agents to genus level (grade is at least 4).
Average grade of all tests is final grade of the study course.

Description of the organization and tasks of students’ independent work

Preparing for tests.

Criteria for Evaluating Learning Outcomes

1. Assessment of laboratory works – passed/not passed.
Tests in entomology.
2. During the test No. 1, students must give answers to typical test questions by choosing right answer from several proposed versions. Student earns one point for every correctly answered question. Maximally, it is possible to earn 50 points. Grade of the test depends on sum of the earned points:
49...50 points – 10 (excellent);
46...48 point – 9 (very well);
42...45 points – 8 (very good);
38...41 points – 7 (good);
34...37 points – 6 (almost good);
30...33 points – 5 (average);
26...29 points – 4 (almost average);
20...25 points – 3 (weak);
14...19 points – 2 (very weak);
<14 points – 1 (very, very weak).
3. The written test (Test No. 2) on insect ecology, monitoring methods, integrated plant protection techniques consists of 25 open-ended questions to which the student provides a written answers. For each question answered completely correctly, the student will receive two points. If the answer is partially correct, then the number of assigned points is reduced accordingly by a step of 0.5 points. The test is considered successfully passed if the student has obtained at least 40% of the maximum number of points. Grades are assigned according to the proportion of points obtained (40% – 4; 50% – 5, etc.), rounding it mathematically.
4. During the oral test (test No. 3), student draws set of ten invertebrates' species economically important for agriculture. Each 'species' consists of preparations of individuals in different developmental stages and also of herbariums of damaged plants by the pest. Each student has 15 minutes to prepare. Student must identify all species and to tell about their biology, ecology and economical importance. Student earns 0.5 points for each properly identified species. Similar amount of points are earned if student is able to tell about biology, ecology and economical importance of each species. Therefore, it is possible to earn 10 points in this test. Final grade of the test is sum of points earned.
Tests in phytopathology.
5. The final mark is the average point of the four theoretical tests. Every question is evaluated separately in each test, and the points are summed up. The final mark can be extended by one point if the practical test is assessed at 7.5 and higher.

Compulsory reading

1. Augu slimības. (2003) B. Bankinas red. Jelgava, LLU, 247 lpp.
2. Balodis O., Bankina B., Gaile Z., Grantiņa I. (2012) Ziemas rapsis. Jelgava, LLU, 68 lpp.
3. Bankina B., Gaile Z. (2014) Ziemāju labības un to slimības. Jelgava, LLU, 103 lpp.
4. Bankina B., Bimšteine G., Kaņeps J. (2024) Lauka pupu slimības un to ierosinātāji. Jelgava: Latvijas Biozinātņu un tehnoloģiju universitāte – 35 lpp.
5. Bimšteine G., Lepse L., Bankina B. (2014) Kāpostu, burkānu, sīpolu slimības un to ierobežošanas iespējas. Jelgava: LLU, 104 lppOzols E. (1973). Lauksaimniecības entomoloģija. Rīga, izdevniecība “Zvaigzne”, 496 lpp.
6. Priedītis A. (1996) Kultūraugu kaitēkļi. Rīga, Zvaigzne ABC. 296 lpp.
7. Priedītis A. (1997) Derīgie savvaļas dzīvnieki un to izmantošana augu aizsardzībā. Ozolnieki, 112 lpp.

Further reading

1. Bankina.B., Bimšteine G., Kaņeps J. (2021) Vispārējā augu patoloģija: laboratorijas darbi. Jelgava: Latvijas Lauksaimniecības universitāte. – 36 lpp. https://llufb.llu.lv/LLU-studiju-materiali/LF/Vispareja_augu_patologija_LLU_2021.pdf
2. Bankina B., Turka I. (2013) Augu slimību un kaitēkļu uzskaites metodes. Jelgava, LLU, 24 lpp.
3. Plīse E. (2001) Krāšņumaugu kaitēkļi. Jelgava, LLU, 332 lpp.
4. Plīse E.(2002) Augļu koku un ogulāju kaitēkļi. Jelgava, LLU. 48 lpp.

5. Rupais A. (1999). Kokaugu kaitēkļu sugu noteicējs pēc bojājumiem augļu dārzos un apstādījumos. Rīga: Valsts Augu aizsardzības dienests, 271 lpp.

Periodicals and other sources

1. Journal of Applied Ecology. [tiešsaiste]. British Ecological Society. Online ISSN: 1365-2664. [Skatīts 23.02.2019.]. Pieejams: https://besjournals.onlinelibrary.wiley.com/journal/13652664
2. Journal of Applied Entomology. [tiešsaiste]. Blackwell Verlag GmbH. Online ISSN:1439-0418. [Skatīts 12.11.2019.]. Pieejams: https://onlinelibrary.wiley.com/journal/14390418