Module 6 Support pack for Plant pests OR parasites and diseases Gr11

Study & Master Support Pack | Grade 11 CAPS Module 6 Units 1 – 2 Agricultural Sciences Plant pests/parasites and diseases This support pack for the Plant pests/parasites and diseases module in the Agricultural Sciences Grade 10 CAPS curriculum provides valuable revision activities. All activities have the answers provided. Learners can work through these individually at home or these could form the basis of a catch-up class or online lesson. You have permission to print or photocopy this document or distribute it electronically via email or WhatsApp. For more information on our Study & Master CAPS-approved  textbooks and valuable resource materials, visit www.cambridge.org Brighter Thinking | Better Learning

Module 6 – Plant pests/parasites and diseases Unit 1 Weed control management Short questions 1. Various possible answers are provided for the following questions. Write only the correct letter (A–D) next to the question number. 1.1 Invasive alien plants are _____ weeds that pose a threat to biodiversity. A indigenous B exotic C pioneer D host 1.2 A field planted with a narrow-leafed crop becomes infested with a broad-leafed weed. The type of herbicide used to destroy the broad-leafed weed is: A non-selective B selective C insecticides D fungicides 1.3 _____ herbicides are applied before or during planting time and washed into the soil by rain or irrigation. A Contact B Systemic C Pre-emergence D Post-emergence 1.4 Which one of the following is NOT a broad-leafed weed? A Buffalo grass B Blackjack C Dandelion D Dubbeltjie 1.5 A _____ herbicide only kills the parts of the plants onto which it is sprayed. A non-selective B post-emergence C systemic D contact  (5 × 2 = 10) 2. Supply ONE word/term for each of the following descriptions. Write only the word/term next to the question number. 2.1 Undesirable plants that have negative impacts on agricultural land and grazing fields 2.2 Hardy garden and crop weed species that grow well in barren disturbed environments such as roadside verges or overgrazed veld 2.3 An agent that carries weed seeds from one place to another and thereby spreads weeds to places where they did not grow before 2.4 The type of herbicide that is absorbed by the foliage and transported throughout the plant 2.5 The Act that deals with invasive alien plants in South Africa (5 × 2 = 10) 3. Match each description in column B with the correct word/term in column A. Column A Column B 3.1 Monocotyledons A Life cycle completes in one growing season, e.g. milkweed 3.2 Annuals B Broad-leafed weeds, e.g. blackjack and ‘dubbeltjie’ 3.3 Dicotyledons C Two-year lifespan, e.g. wild mustard and carrot weed 3.4 Perennials D Narrow-leafed weeds, e.g. buffalo grass 3.5 Biennials E Long lifespan and regrow vegetatively and sexually  (5 × 2 = 10) Longer questions 4. Name FOUR adaptation features of weeds that allow them to grow better than cultivated crops.  (4) 5. Name FIVE harmful effects of weeds on agriculture and natural vegetation. (5) 6. List the FOUR methods to control weeds and provide TWO examples of each.  (4 × 3 = 12) S T U DY & M A S T E R S U P P O R T PA C K S 1

Unit 2 Plant diseases/pests and their control Short questions 1. Various possible answers are provided for the following questions. Write only the correct letter (A–D) next to the question number. 1.1 Some chewing insects such as caterpillars feed on the underside of leaves and eat all the leaf tissue between the veins so that the leaves become: A defoliated B skeletonised C chlorotic D retarded 1.2 _____ chew the stems of succulent plants and seedlings just above the ground and the whole plant collapses. A CMR beetles B Codling moths C Cutworms D Red spider mites 1.3 Which one of the following is NOT a chemical control method for plant diseases? A pesticides B fungicides C niticides D herbicides 1.4 Select the correct combination of facts about fungal diseases in stored seeds/grains. (i) Mouldy smell and taste (ii) Discolouration of grains (iii) Enhance germination (iv) Grains/seeds cake together A (i), (ii), (iii) B (i), (ii), (iv) C (ii), (iii), (iv) D (i), (ii), (iii), (iv) 1.5 Which one of the following is NOT a favourable condition for the germination, growth and multiplication of bacteria? A good ventilation B high humidity C high temperature D overcrowding of plants  (5 × 2 = 10) 2. Supply ONE word/term for each of the following descriptions. Write only the word/term next to the question number. 2.1 Plants that are under severe stress due to adverse weather conditions and inadequate nutrition easily become infested by pests 2.2 The type of cells through which fungi reproduce asexually 2.3 The type of fertilisation whereby female aphids give birth to daughter aphids without fertilisation 2.4 The nymphs of aphids cast off their skins several times until they reach maturity 2.5 Signs shown by plants that they are infected with diseases or infested by pests  (5 × 2 = 10) 3. Match each description in column B with the correct word/term in column A. Column A Column B 3.1 Chewing pests A Fruitflies 3.2 Nematodes B Caterpillars, beetles, grasshoppers, cutworm 3.3 Stinging pests C Herbivorous snails and slugs 3.4 Scales D Eelworm, army worm, cutworm 3.5 Molluscs E Bodies have waxy covering (5 × 2 = 10) 2 S T U DY & M A S T E R S U P P O R T PA C K S

Longer questions 4. Study the following two life cycles of insect pests and then answer the questions. aphid life cycle 2 3 viviparous parthenogenetic females 5 viviparous female-founder producing females 6 1 4 viviparous female producing sexual forms moth lifecycle 7 A B Tabulate the differences between A and B with reference to: 4.1 Type of life cycle (2) 4.2 The number and stage in the life cycle of each  (7) 4.3 Type of pest with reference to their feeding habits  (2) 4.4 ONE example of insect pests that have each type of life cycle  (2) 4.5 Any TWO plants/crops/trees infested by the pests (4) 4.6 Method of how each of A and B infest and negatively affect plants  A (3) B (4)  5. Study the following images and then answer the questions. A B C Tabulate the differences between A, B and C with reference to: 5.1 Type of micro-organisms causing the diseases (3) 5.2 The disease  (3) 5.3 An example of a plant that is negatively affected by the disease  (3) 6. Name FOUR safety precautions that need to be taken before using chemicals to destroy plants pests.  (4) 7. Name FOUR cultural control measures for preventing plants from being infected by diseases.  (4) 8. Answer the following questions about the roles played by the South African government in plant protection: 8.1 Name the organisation responsible for research and development of plant protection in South Africa. (1) 8.2 Briefly explain THREE roles played by the South African government in plant protection. (3) S T U DY & M A S T E R S U P P O R T PA C K S 3

Memorandum Unit 1 Short questions 1.1 B 1.2 B 1.3 C 1.4 A 1.5 D  (10) 2.1 weeds 2.2 pioneer 2.3 vector 2.4 systemic  2.5 Conservation of Agricultural Resources Act (CARA)  (10) 3.1 D 3.2 A 3.3 B 3.4 E 3.5 C (10) Longer questions 4. Adaptation features of weeds (any four): • Grow easily in disturbed environments • Produce large quantities of seed • Seeds are easily dispersed by wind, animals or birds • Seeds can persist in the soil for many years • Weeds can multiply several times in one growing season • Perennial weeds have underground stems that spread out under the soil surface • Weeds such as ivy have creeping stems that take root and spread out over the surface of the soil • Can survive under extreme environmental conditions such as drought • Some weed species can survive fires  (4) 5. Harmful effects of weeds on agriculture and natural vegetation (any five): • Smother plants: deprive them of space, sunlight, nutrients and moisture necessary for photosynthesis • Retard growth of crops: leads to lower production and financial losses • No natural enemies to control their spread • Spread rapidly and invade and displace natural vegetation • Damage to ecosystem diversity • Use more water than natural vegetation • Invade water courses and deplete water resources • Biodiversity is negatively impacted • Hosts for pests that attack crops • Some weeds release chemicals into the soil: prevent other plants from thriving • Production costs of farmer increase: leads to increase in food prices • Grow more vigorously than crops: upset ecosystem • Some plant parts contain allelochemicals that inhibit the growth of native plant species  (5) 6. Methods to control weeds (any two examples of each): • Mechanical control: – Handpulling of weeds – Burning infested land or fields – Remove flowers of inflorescences to prevent seed dispersal – Chopping, cutting or clear-felling trees – Ring-barking trees – Crop rotation – Planting cover plants to crowd out weeds – Ploughing weeds deep into the soil before seeding – Intercropping plants – Mulching the soil surface to prevent weed seeds from germinating • Chemical control: – Selective herbicides – Non-selective herbicides 4 S T U DY & M A S T E R S U P P O R T PA C K S

• Biological control: – Species-specific insects or other invertebrates – Fungal diseases – Complete success in controlling red water fern, water lettuce, Port Jackson acacia, red sesbania and Australian pest pear with various biocontrol agents – Significant success controlling jointed cactus, prickly pear, parrot’s feather, water hyacinth (type of weevil used) and silky hakea • Integrated weed control: – Combination of two or more control methods – Felling of trees (mechanical control), followed by herbicides (chemical control) and then release biocontrol agents on the regrowths  (12) Unit 2 Short questions 1.1 B 1.2 C 1.3 D 1.4 B 1.5 A (10) 2.1 susceptible 2.2 spores 2.3 parthenogenesis 2.4 moult / moulting 2.5 symptoms  (10) 3.1 B 3.2 D 3.3 A 3.4 E 3.5 C (10) Longer questions 4. Life cycles of insect pests: A B 4.1 Complete life cycle Incomplete life cycle (2) 4.2 1: Egg 5: Eggs 2: Larva 6: Several nymph stages 3: Pupa 7: Adult 4: Adult (7) 4.3 Chewing Sap-sucking (2) 4.4 Moths, caterpillars, beetles, bollworm, etc. Grasshoppers, termites, scales, bugs, aphids, etc. (2) 4.5 Apples, pears, quinces, peaches, plums and cherries, Herbaceous plants such as roses, beans, cabbage, etc. potatoes, etc. (4) 4.6 • Female lays eggs on fruit or stems • Female lays eggs that hatch into wingless • Larvae eat outer flesh of the fruit female nymphs • Larvae bore into the core of the fruit and create • Wingless nymphs give birth to daughter tunnels aphids • Some daughter aphids develop two pairs of transparent wings • They grow larger and fly off to infest new plants (3) • Aphids suck in sugar from the plant sap (4) (7) 5. Micro-organisms: A B C 5.1 Fungi Bacteria Virus (3) 5.2 Rust Bacterial wilt Mosaic virus (3) 5.3 Beans, strawberries, roses, etc. Maize, potatoes, tomatoes, Roses, beans, tobacco, tomatoes, bananas, etc. potatoes, etc. (3) 6. Safety precautions when using chemical products (any four): • Identify pest or disease to select correct chemical. • Correct application time. S T U DY & M A S T E R S U P P O R T PA C K S 5

• Avoid direct contact/wear safety clothing. • Mix sprays well in well-ventilated areas. • Do not eat, drink or smoke when working with chemicals. • Spray on calm, dry days. • Do not spray on harsh sunlight days. • Treat all products as potentially dangerous. • Wash your hands and eyes with clean running water if contaminated.  (4) 7. Cultural control measures to prevent plant diseases (any four): • Remove weeds, they may be hosts for disease-causing organisms. • Select cultivars that are resistant to diseases. • Treat seeds with hot water to control seed-borne diseases. • Ensure optimum soil conditions and cultivation practices. • Prevent overcrowding and poor air circulation. • Avoid misting of plants. • Disinfect pruning tools. • Crop rotation with crops that are disease-resistant. • Intercropping to prevent spread of diseases. • Use registered certified disease-free seed. • Do not water plants late in the afternoon when it is hot. 8. Roles played by the South African government in plant protection: 8.1 Agricultural Research Council (ARC) (1) 8.2 Plant protection roles (any three): • Legislation for plant protection • Breeding and registration of disease-resistant cultivars • Research on viral, bacterial and fungal diseases • Effective application of pesticides • Quarantine of imported biocontrol agents • Prevent the importation of diseased or pest-infested plants • Certify that all imported and exported plants or plant parts are healthy and free of diseases and pests • Control measures when a disease of pests threatens to affect natural vegetation negatively • Render quarantine services • Evaluate and manage risks of imported biocontrol agents  (3) 6 S T U DY & M A S T E R S U P P O R T PA C K S