R2104 UNDERSTANDING PLANT PROPAGATION

Transcription

1 Including Examiners Comments R0 UNDERSTANDING PLANT PROPAGATION Level Monday 0 June 06 :50 5:0 Written Examination Candidate Number: Candidate Name: Centre Number/Name:.. IMPORTANT Please read carefully before commencing: i) The duration of this paper is 50 minutes; ii) iii) iv) ALL questions should be attempted; EACH question carries 0 marks; Write your answers legibly in the lined space provided. It is NOT necessary that all lined space is used in answering the questions; v) Use METRIC measurements only; vi) vii) viii) Use black or blue ink only. Pencil can be used for drawing purposes only; Where plant names are required, they should include genus, species and where appropriate, cultivar; Where a question requires a specific number of answers; only the first answers given that meet the question requirement will be accepted, regardless of the number of answers offered; ix) Please note, when the word distinct is used within a question, it means that the items have different characteristics or features. Ofqual Unit Code D/505/965 Please turn over/..

2 Q a) ANSWER ALL QUESTIONS Name ONE distinct plant that can be propagated by EACH of the layering methods stated, by completing the table below. Layering method Named plant Simple Serpentine Air Describe the method of air layering using a labelled diagram. 7 Total Mark Please see over/..

3 Q Describe the propagation of Hosta species under EACH of the following headings: i) time of year; ii) lifting; iii) dividing; iv) aftercare. 3 i).. ii).... iii) iv).... Total Mark.. Please turn over/.. 3

4 Q3 a) c) State the meaning of the term seed dormancy..... List FOUR environmental factors required for successful seed germination..... Describe how TWO of the factors listed in are provided when sowing seeds indoors.... Total Mark Please see over/..

5 Q a) Name ONE plant from EACH group that can be propagated by seed, by completing the table below. Plant group Botanical name of plant Vegetable crop Hardy annual flower Half-hardy annual flower Grass Describe the sowing of carrot seed in open ground under EACH of the following headings: i) soil preparation (secondary cultivation); ii) appropriate sowing technique. i). ii). Total Mark Please turn over/.. 5

6 Q5 a) State how EACH of the following plants are propagated, by completing the table below. Plant Saintpaulia ionantha Method of propagation Streptocarpus rexii Camellia japonica Begonia Rex Cultorum Group Describe the environmental conditions required for ONE of the plants propagated in a) to ensure successful rooting. c).... Name ONE pest and ONE disease that can affect cuttings during the rooting process. Total Mark Please see over/.. 6

7 Q6 a) c) State TWO limitations of propagating plants by vegetative means Name ONE plant propagated by deciduous hardwood cuttings. Describe the propagation of the plant named in from collection up to insertion..... ******* 7 7 Total Mark

8 These questions are the property of the Royal Horticultural Society. They must not be reproduced or sold. The Royal Horticultural Society, Wisley, Woking, Surrey GU3 6QB. Charity Registration Number: 879/SC0386 8

9 R0 UNDERSTANDING PLANT PROPAGATION Level Monday 0 June 06 Candidates Registered 57 Total Candidates Passed % Candidates Entered % Passed with Commendation % Candidates Absent/Withdrawn % Passed 9 0.8% Candidates Deferred 8.0% Failed 06.65% Senior Examiner s Comments: Candidates should be able to demonstrate a good range of plant knowledge and be able to give accurately named plant examples where appropriate. Common names and generic names are often too vague and cannot be rewarded in the positive manner that genus, species and where appropriate, variety/cultivar can. This is particularly important when answering questions relating to particular (named) plant(s). Marks can only be awarded for these narratives where the example(s) are correctly and fully identified. Candidates must be able to display accurate knowledge of the technical terms and concepts detailed in the syllabus, in the context of horticulture and also be aware that wider interpretation will not be rewarded. The examination should be regarded as a possible introduction to higher level studies, which will only be open to those who are in possession of a clear understanding of the horticultural terms and concepts which are current. 3 The introductory rubric given on the first page of each question paper should be read carefully by candidates. At each examination there are a significant number of candidates who ignore or misread the instructions given and consequently may not perform as well as they could have done. 9

10 Candidates should pace themselves during each paper. The most successful candidates allow sufficient time to read the question thoroughly before answering it and also take time to read through their answers. They should take care to write as legibly as possible, so that the examiner is in no doubt about what is intended. 5 Candidates need to interpret key words within questions, particularly those such as state, list and describe. Questions requiring descriptions or explanations obviously require a more detailed answer than those requiring a list. 6 It is important to ensure that responses to questions are to the point. Candidates should bear in mind that small sketches might be used to convey information more succinctly than words. 7 Successful candidates ensure that their answers are focused and to the point. It is disappointing when they cannot be rewarded for their efforts because the answer is irrelevant to the particular question. Candidates should take note of the mark allocation for specific sections and allocate their time and efforts accordingly. 8 Diagrams can enhance an answer and where appropriate can replace detailed descriptions. They should be large, clear and well annotated, ensuring that labels are properly attached to the features they describe. Diagrams should preferably be in pencil. Colour may be used successfully but only where it is relevant to the answer. 9 In each examination it is clear that some candidates are ill prepared to answer papers of the type set. It is essential that candidates have the opportunity to practice questions. Ideally some papers should be answered in a time constrained situation. Appropriate feedback must, in any case be provided. 0

11 Q a) Name ONE distinct plant that can be propagated by EACH of the layering methods stated, by completing the table below. Layering method Named plant Simple Serpentine Air Describe the method of air layering using a labelled diagram. 7 Qa) Most candidates named a suitable plant that can be propagated by specific methods of layering. Acceptable answers that were awarded full marks included: Simple layering Cotinus coggygria and Magnolia x soulangeana. Serpentine layering Clematis Montana and Wisteria floribunda. Air layering Ficus elastica and Hamamelis mollis. Q Candidates who provided detailed descriptions of the method of air layering and included a diagram, gained full marks. The best descriptions included: Air layering is carried out on healthy, true to type plants Air layering is carried out in late spring or summer on hardy plants An upward slanting cut is made through the node which is kept open by the use of a matchstick Medium strength hormone rooting powder is applied to the cut Moist sphagnum moss is placed around the cut surfaces Clear or black polythene is used to cover the moss and is tied at both ends with raffia or fine twine Air layering is carried out on young green wood Adjacent side shoots to the cut are removed to make binding the cut surface easier

12 Q Describe the propagation of Hosta species under EACH of the following headings: i) time of year; ii) lifting; iii) dividing; iv) aftercare. 3 Q) Candidates who described the propagation of Hosta species provided the following details to gain full marks. i) Hosta species are propagated in early spring or during the autumn. ii) iii) iv) A plant which is true to type is carefully lifted and any excess soil is washed off before it is placed in a bag or suitable container ready to be divided. The clump is placed on a bench or table and divided using a knife or spade to include at least a growth bud and some root growth. The old centre of the plant is discarded and the plant is checked for any evidence of vine weevil damage. Small divisions are potted into litre pots using either a soilless growing media or John Innes potting mix. Large divisions can be replanted into prepared ground at the same level as they were originally, i.e. with the buds level with the soil surface. All new plants are watered as required and weeded and the flower buds are removed in the first year. The plants can be mulched and it is important to control any pests or diseases, e.g. slugs.

13 Q3 a) c) State the meaning of the term seed dormancy. List FOUR environmental factors required for successful seed germination. Describe how TWO of the factors listed in are provided when sowing seeds indoors. Q3a) Candidates who stated that seed dormancy is when a viable seed is unable to germinate due to either environmental or physical factors, e.g. a hard seed coat, were awarded full marks. Q3 The majority of candidates listed: moisture, temperature, oxygen and light/dark as the environmental factors required for successful seed germination, and gained full marks. Q3c) Those candidates who were able to describe how the environmental factors are provided when sowing seeds indoors were awarded full marks. Acceptable answers included: Temperature is provided by placing the seed trays in a closed case with bottom heat or a propagator at a temperature of 8-0ºC. Moisture is provided by watering the trays before the seeds are sown and during germination. Oxygen is provided by using a suitable growing media which has an open texture and good air filled porosity. Light/dark light is provided by either not covering the seeds or covering them with vermiculite. Dark is provided by covering the seeds after sowing. 3

14 Q a) Name ONE plant from EACH group that can be propagated by seed, by completing the table below. Plant group Botanical name of plant Vegetable crop Hardy annual flower Half-hardy annual flower Grass Describe the sowing of carrot seed in open ground under EACH of the following headings: i) soil preparation (secondary cultivation); ii) appropriate sowing technique. Qa) Candidates provided a range of suitable plants for each of the groups of plants propagated by seed, and gained full marks. Acceptable answers included: Vegetable crop e.g. Daucus carota and Lactuca sativa. Hardy annual flower e.g. Nigella damascena and Helianthus annuus. Half-hardy annual flower e.g. Lobelia erinus and Salvia splendens. Grass Lolium perenne and Festuca rubra. Q Most candidates were able to describe the soil preparation and sowing of carrot seed in open ground, and were awarded full marks. Suitable answers included: i) The soil is prepared by raking the ground roughly level before consolidating it by treading. A base fertiliser can then be applied before raking the area in two directions to create a fine tilth for seed sowing. ii) A drill is drawn using a draw hoe or the back of a garden rake against a taut line or a straight edge to a depth of mm. The drill is watered before the seed is sown thinly and evenly along the drill. The seed is covered by drawing the soil over the drill.

15 Q5 a) State how EACH of the following plants are propagated, by completing the table below. Plant Saintpaulia ionantha Streptocarpus rexii Camellia japonica Begonia Rex Cultorum Group Method of propagation Describe the environmental conditions required for ONE of the plants propagated in a) to ensure successful rooting. c) Name ONE pest and ONE disease that can affect cuttings during the rooting process. Q5a) The majority of candidates named a suitable method of propagation for the named plants, and were awarded full marks. Acceptable answers included: Saintpaulia ionantha leaf petiole cuttings. Streptocarpus rexii leaf lamina section cuttings or midrib cuttings. Camellia japonica leaf bud cuttings or semi-ripe stem cuttings. Begonia rex Cultorum Group leaf slashing or leaf square cuttings. Q5 Candidates who described the environmental conditions required to propagate a specific plant were awarded full marks. Suitable answers for Saintpaulia ionantha included: Temperature e.g. 8 - ºC and the use of shading to control temperature and to reduce sun scorch. Moisture and air content a suitable level is required in the growing media to maintain the turgidity of the plant and enable respiration to take place. Humidity ventilation and airflow are required to reduce the occurrence of fungal diseases and the level of humidity. Light Appropriate levels for growth with the provision of shading to avoid sun scorch if high levels occur. Q5c) Candidates named a range of pests and diseases that can affect cuttings during the rooting process. Acceptable answers included: Pests aphids, mealy bug, two spotted mite, sciarid fly, slugs and whitefly. Diseases damping off, grey mould and downy mildew. 5

16 Q6 a) c) State TWO limitations of propagating plants by vegetative means. Name ONE plant propagated by deciduous hardwood cuttings. Describe the propagation of the plant named in from collection up to insertion. 7 Q6a) The majority of candidates were able to provide a range of limitations of propagating plants by vegetative means, and gained full marks. Suitable answers included: Limited availability of propagation material Lack of genetic material Transmission of pests and diseases is more likely on propagation material Requirement for different and often complex propagation methods, e.g. grafting Need for more complex facilities for some methods of propagation, e.g. bench grafting and tissue culture Requirement for healthy stock plants Q6 Candidates named a range of suitable plants that are propagated from deciduous hardwood cuttings, and gained full marks. These included: Cornus alba Sibirica, Buddleja davidii, Ribes nigra, Forsythia x intermedia and Philadelphus coronarius. Q6c) Candidates who were awarded full marks described the propagation of a suitable plant e.g. Cornus alba Sibirica. The propagation material is collected from known plants that are pest and disease free and true to type, during October and November. Current seasons woody material which is 6 8mm in diameter is removed from the parent plant by cutting above a node. Cuttings 5 0cm in length and of pencil thickness are prepared by making a horizontal cut at the base below a node and an angled cut at the top of the cutting above a node. Any remaining leaves are removed. The base of the cuttings are treated with hormone rooting powder and are graded prior to insertion. ******* 6