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Mount Usu / Sarobetsu post-mined peatland
From left: Crater basin in 1986 and 2006. Cottongrass / Daylily
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IndividualOxford English Dictionary, Internet version
Ramet (ラメット): an individual that develops from a genet or another ramet and is a product of asexual reproduction
Efficiency (効率)the ratio of useful output to total input
r = P/C × 100 (%), |
Solar energy ⇓ x% of energy absorbed for photosynthesis x% = efficiency Ex. Plant productivity and use of solar energy Plant productivity (in a year)(1500-6000 kg carbon/ha/yr) × (8000 kcal/kg carbon) = 12 × 106 to 48 × 106 kcal/ha/yr Solar radiation arriving ground level= 11.6 × 109 kcal/ha/yr (Higher) Efficiency(48 × 106)/(11.6 × 109) × 100 = 0.4% Quiz. How is the lowest efficiency?Water use efficiency 水利用効率(de Bello et al. 2021) Trait-based ecologyproperty ≠ traitResponse traits and groupsallowing organisms to cope with a particular stress, i.e., to be able to survive, grow and reproduce under the experienced stress level or under different environmental conditionsEffect traits and groupseither have an effect on other trophic levels, as in the case of predator-prey intaractions or mutualistic relationships, or on ecological processes, such as nutrient cycling, pollination or primary productivity |
[ embryology ]
[ sex ]
I. asexual reproduction (vegetative reproduction) II. sexual reproduction |
iteroparous (多回繁殖性): multiple reproductive cycles over the course of its lifetime semelparous (一回繁殖性): a single reproductive episode before death |
= agamic reproduction, or apomixis (clone) Reproduction, not concerned with gametes
One or more individuals develop from a part (e.g., cells and spores) of the parent At cell levelAsexual gametic reproduction (無性配偶子生殖)= gamogony= somatic reproduction, all-inclusive term Division (分裂)Cell division of monocellular organismsBinary division (二分裂, 二分法)
Transverse division (横分裂): bacteria, paramecium Multiple division (複分裂, 多分法) trypanosome Budding (出芽)yeasts (division, s.l.) Sporogenesis (胞子生殖)New individuals are produced by spores (spore cells)Ex. bacteria, mosses, ferns, algae, (seed plants) Diplospory (generative apospory, 複相胞子生殖): the megagametophyte arises from a cell of the archesporium. Ex. Taraxacum officinaleApospory (somatic apospory, 無胞子生殖): the megagametophyte arises from some other nucellus cell |
planospore (遊走子): a spore motile by flagellum(a) = a zoospore At tissue levelDivision (分裂)sea anemone Budding (出芽)hydra, sea sponge Propagule (栄養体生殖, 栄養体繁殖)Stolones and runners (匍匐枝, ストロン), developed on the ground surfacesaxifrage, strawberry Rhizomes and tubers (地下茎), developed in the groundpotato, Colocasia, lotus, iris, Chrysanthemum Storage and tuberous root (貯蔵根, 塊根)sweet potato, dahlia Adventitious buds (むかご, 珠芽, 肉芽), on cut stems or fallen leavesJapanese yam, lily False vivipary (偽胎生): vegetative progagules within a flowerArtificial vegetative reproduction
cuttage, layerage, grafted tree, division |
= reproduction (s.s.), = amphimixis reproduction induced by gametes → the combinations of genes are changed from parents to the child(ren) Agamospermy or apomixis (無融合種子形成)Gametophytic apomixis: more in tropical regions
Adventitious embryony: northern elements Agamic complex (無融合性複合体)agamosperms, related sexual speciesA. Normal sexual cycle Sporophyte 2n → Spore n → Gametophyte n → [Fertilization] → Zygote 2n → Seed with embryo 2n B. Cagetophytic apmixis___[Diplospory]_________________[Diploid parthenogenesis] ___Embyro-sac mother cell 2n ↘__↗ Egg cell 2n____↘ Sprophyte 2n 〈____Gametophyte 2n____Seed with embryo 2n ___Sotamtic cell of ovule 2n__↗__↘ Sotamtic cell 2n ↗ ___[Apospory]___________________[Apogamety] C. Adventitious embryony Sprophyte 2n → Sotamtic cell of ovule 2n → Seed with embryo 2n Fig. 31.1. Modes of agamospermous reproduction. A normal sexual life cicle is shown for comparison. zygote (接合子): the cellular product of gametic union Apomixis (無配偶生殖)Reproduction is achieved without fertilisation, the sexual process being wholly or partly lost (the term and its definition are according to Winkler 1908). Two types of system are found: vegetative apomixis and agamospermy.1) Vegetative apomixis While for a time plants are usually rooted to the precise spot where germination and establishment has occurred, radial growth by means of rhizomes, stolons, runners, etc., is characteristic of many perennial species. Bulbils (small, readily detachable propagules, often borne on aerial structures, (Figure) are found in some species. Plants arising from such propagules will, of course, have the same genotype as the parent plant. Certain crop-plant varieties, e.g. potatoes, and such familiar garden plants as Pelargonium (the gardener's 'Geranium') are regularly propagated by vegetative means. 2) Agamospermy In certain plants normal seed is set but no sexual fusion has occurred in its production. Offspring have the genetic constitution of the plant which produces them. A plant reproducing by seed apomixis or agamosperrny has all the advantages of the seed habit (dispersal of propagules and a potential means of survival through unfavourable seasons) without the risks which may be associated with pollination. As there is no essential genetic difference between simple agamospermy and asexual reproduction, Winkler grouped these two types of reproduction under the common term of apomixis. Fig. 7.6. Bulbils. (a) Saxifraga cernua: 1. (× 1); 2. a cluster of bulbils; 3, bulbils in various stages of development (From Kerner 1895) (b) Poa alpina:1. P. olpina with bulbils replacing its flowers (× 1); 2. a portion of the inflorescence; 3. a miniature grass-plant developed between the glumes of a spikelet of P. alpina. |
Apospory (無胞子生殖)Figure 31.2. Apospory in Crepis occidentalis. (A) Embryo-sac (胚嚢) mother cell dividing (ESMC) and below it an enlarging somatic cell (SC). (B) Linear tetrad above and somatic cell below developing into aposporic embryo-sac (AES). (C) Embryo-sac mother cell degenerating in first division and below it a one-celled aposporic embryo-sac (AES). (Stebbins & Jenkins 1939). (D-G) Diplospory in Antennaria porsildil. Embryo-sac mother cell developing into unreduced embryo-sac. (Urbanska 1974) Pollination (授粉)Self-pollination (自家授粉, s.l.) = autogamy + geitonogamy: a form of pollination in which pollen from the same plant arrives at the stigma of a flower
• autogamy (自家生殖/自家受精/自家受粉, s.s.) ≈ self-fertilization: pollen is transferred to the stigma of the same flower |
The research of breeding or propagating plants and animals (agriculture and husbandry)
environmental variations: temperature, humidity, wind, soil, etc. Tolerance Economical value Management and cultivation Artificial regeneration: using seed, seedlings and rooted cuttings |
Breed improvement (品種改良)Tree breeding (林木育種)Cutting (挿木) |