Topics 28-57 Flashcards
- Nitrogen cycle. The main processes of nitrogen cycle at the plants
Cycle: Nitrates > nitrogen> ammonia –> protein, NO3, oxidation w. bact. ATP liberated
BNF, biological nitrogen fixation:
N2+8(H^+)+8e-+16ATP->2NH_3+H2+16ADP+16P
Denitrification: bad for plants, good for enviroment
- Growth and development of the plants. Curves of growth
Development: sum of qualitative proc.
Growth: sum of quantitativ changes, metabolic proc.
Germination -> vegetativ develop. -> flowering phase -> fertalization, pollination, -> fruit production -> latent phase
- Plant hormones
Group of hormones :
1. Auxins (beta-indol acetic acid)- stimulation of longit. growth, resp. nucleic acid synth., cell wall synthesis
- Cytokinins (kinetin) - stimulation of c. div., stimul. of nucleic acid and photosynth., inhibition of senescence
- Gibberellins - longit. growth, regulation of flowering
- Abscisic acid - stimulate abscision (bladfall om høst), inhibit all other function (like growth)
- Ethylen (ethen?) - stimulation of ripening of fruits, inhibit all other functions
- Main processes of the development
- Seed dormancy: low intensity
- Germination: first - iMhinhibtion, water uptake. Second - intensive phase: hydrolyses of: starch -> glucose + ATP, oil-> carbohydrates, proteins->AA->synth of new proteins
- Vegetative development (most important): factors; light (photomorphogenesis) + tempterature
- flowering (factors): temp, light (photoperiodism): neutral plants; weeds - its not important with light, short day plants: need at about 8 hours, long day plants 14 hours
- Polliniation/fertillization problems: interspecific incompatibility, autoincompatibility -> some species need other variants of the spp nest to fertilizate
- embryo-, seed- and fruit formation, 4 subphases: 1. c. div. 2. c. elongation. 3. ripening: ethylen concentration is high
- opening of fruit
- Senescence: last period of life in the plants
- Movements of plants
2 main groups: active and passive
Active movements
1. Taxis: Movement of lower plants. Is regulated by a stimulus gives movement towards or away from t. stimulus
Types: -chemotaxis: chemical stimulus, has both neg. and pos. response, Phototaxis: light, stimulus, if high intensity -> neg. but in nature always pos.
- Aerotaxis, hydraotaxis, termotaxis, all has pos. and neg. response
- Trypism:
Mainly movement of growth in multicellular. Depend on direction of stimulus.
Types: - Phototrppism: growth towards light
- Geotropism: induced by gravity e.g. t. roots
- chemotropism, thermotropism etc.
- Botanical characterization of the family Poaceae
Class of monocots
Morphology
- Root system - fibrous root system
- stem: nodes and internodules on the stem
- leaf: ligule, auriculas, leaf base, WITHOUT petiole!
- flowers: inflorescens (group of flowers), spike or panicle
- fruits: caryopsis (kernel, grains) type of simple dry fruit
Phases of development: 1. germination 2. tillering 3. shooting 4. heading of corn 5. flowering - pollination
Phases of development: A. Green ripening B. Yellow ripening (waxy) C. Total ripening D. Overripening
Possibilites of use: green plant - alone or in mixture, grains as meal or as bran. Straw
Utilization of grass species; cereals, pasture grasses, sugar producing grasses, building materials, ornamental purpose
- Botanical characterization of the family Fabaceae
Glass of dicots
- Roots: Taproot system, root nodules (Rhizobium bac.) N-fixation
- Flower: Papilinoid (fabacous) flower
Big part: Vexillum, the two similar = ala, middle =karina
- fruit - Pod (legume) - dehiscent or dry, inside -> seed
Protein: 20-43% (high lysine)
Less carbs, some vitamines
Mineral elements: Ca, P
Poisons and antinutritive materials
- Cereals (wheat, rye, Triticale: biology and utilization)
Poaceae - C3 plant
Wheat (Nr.1 most used) - triticum aestivum
- Exists hard (protein 13-16%) and soft wheat (more carbs, proteins 8-11%)
- spring wheat (flowering same season) ans winter (flowers only after cold period)
Utilization: Bread, by-products of milling, nutrition for animals. by-products bran and straw
Rye - secale cereale
- used as pioneer crop to improve wasteland and sterile soils
- Should be mixed -> alone causes sticky mass in mouth
- similar to wheat in composition, more lysine
- antinutritives: polyphenols, ergot body
Triticale - triticum secale
- hybrid wheat and rye, more tasty then rye
- 12-16% protein, high lysine content
- can survive in poor soils
- used as a forage crop
- Cereals (barley, oat, rice: biology and utilization)
Poaceae - C3 plants
Barley - hordeum vulgare (2, 4 or 6 rowed barley)
- 11-18% protein. AN: binding effect, mechanical damage
- Caryopsis used for animal feed, brewing malts and humn diet
- straw used for litter
Oat - Avena sativa
- insensitive to soil conditions and acidity
- best ceral in protein and oil, excellent nutritive qualities. Good amino acid balance and mucilage components. Vit-E
- Human nutrition and as forage for breeding animals
Rice (nr. 2 most used) - Oryza sativa
- semiaquatic plant
- annual
- hollow stem
- food for more then 50% of the worlds population
- low in protein but good quality, very good digestability, vitamin B and E. AN: siliaca and oxalates.
- Cereals (millets: botany ans utilization)
Panicum miliaceum - common millet
- naked grains
- one fertile and one sterile floret
- may cause panicum photosensitization
- high crude fiber
- utilization: former human nutrition, today: poultry & birds, straw for sheep
Setaria italiaca - Foxtail millet
- grown under drought conditions
- short growth season
- used for human consumption, feesing livestock and birds. hay and silage
- may be toxic for horses due to setarian
Sorghum millets:
- human nutrient, caryopsis for forage, grazing also silage
- mais-like plants
Tex. Sorghum bicolor and Sorhum sudanense
- Cereals (maize: biology and utilization)
Poacea - C4
Corn: (Nr. 3)
- zea maiz
4 types: dentiformis, vulgaris, saccharatum, microsperma
- best energy value. - needs N, P, K
- fibrous root system, they have climbing roots modified to bear weight
- has black layer as sign of maturity
- annual plant, one sterile and one fertile floret/spiklet
Harvest and utilization:
Rain corn: harvest with classical hand method
Silage corn: cutting ut - compression, results in bulk feed for ruminants
Green corn: harvest, tassling - flowering
CCM (corn cob mix) for monogastric animals
Storage: Drying, fluid storage,chemical methods
- Antinutritive materials and their importance
Protease inhibitors - Lower protein digestability, pancrease
Amilase inhibitors - Lower carbohydrate, digestability
Lectines - Growth inhibition, hemagglutination
Saponins - Growth inhibition, hemagluttination, bloating
Oligosacharides - bloating, Jerusalem artichoke
Fitinic acid - Formation of metal complexes
Polyphenols, eg. Tannins - Formation of protein complexes, inhibit absorbtion of minerals
Poisonous amino acid - CNS symptoms
Chinolizidin alkaloids - Growth inhibition, liver disorders
- Pulse crops (forage legumes: biology and utilization)
Fabaceae - grown for their seeds or fruits
- the fruit - pod is dry with large seeds
- fix nitrogen through Rhizobium (root nodules)
- more protein than (20-43% protein)
- Poisnonous and antinutritive materials: protease inhibitors (digerst enzym for protein) -> trypsin, chymotrypsin
Amylase
Contains tannins (in greater amount) - inhibit absorbtion of minerals and alkaloids
Utilization:
- Glycine max: nutrients for humans, forge (meal, oil cake and green plant), oil plant
- Pisum sativum: forage (meal), straw for sheep, green manure used for improvement of soil, human consumption.
- Phaseolus vulgaris: human consumption & straw for sheep
- Lens culinaris: human consumption and straw for sheep
- Lathyrus sativus: forage, straw and green manure
- Vicia faba: human consumpt., forage (seeds), green forage
- Cicer arientinum: human consumption and forage
- Oil crops (biology and utilization)
The fruit or seed contains 20-50% fatty oil
Twice as much energy/g than carbohydrates or protein
Rich in Phosphor and poor in Ca
The oil is found in the cotyledon, endospermium and/or embryo (corn)
Have toxic and antinutritive factors
Have saturated fatty acids
Production of oil: A. Mechanical method - pressure
B. Extraction with solvents -> oilcakes and meals
There are non-drying, semi-drying and drying oils
Utilization: human nutrition, forage, oil cake, medicine and in industry
Brassica napus conv. oleifera - Oilseed rape Helianthus annus - sunflower Ricinus communis - Castor bean Linum usitatissimum - flax Cannabis sativa - hemp Glycine max - soy bean Gossypium hirsuturm - cotton Arachis hypogaea - peanut
- Forage legumes (biology and utilization)
Chemical composition: independent on nitrogen source.
high protein and valuable sources of minerals
Disadvantages: Contains phytoestrogens -> decrease or loss of herd fertility. toxic glucosides, toxic amino acids -> rumina swelling because of accumulated gases (trifolium)
especially Lucerne and red clover can be attacted by stem paracite, Cuscuta campestris. Not toxic
Fabaceae; small seeded species. Grown for stem/leaves, eaten by animals. Independent from nitrogen sources. Rich in proten and mineral, good digestability.
Different antinutritives, toxical compounds, some-> bloating
E. g.
- Medicago sativa, Alfalfa -> queen of forage crops
- trifolium, clovers -> red can cause bloating or secondary photosensitization
- onobrychis viciifolia, lotus corniculatus, melilotus albus, coronilla varia, anthyllis vulneraria
Custcuta campestris (dodder species) dense clumpes
