Titlebook: Viability of Seeds; E. H. Roberts (Professor of Crop Production) Book 1972 Chapman and Hall Ltd 1972 growth.plants.seed.soil

柳树；枯黄

恃强凌弱的人

Cytological, Genetical, and Metabolic Changes Associated with Loss of Viability, earliest relevant observation to be that of De Vries (1901) who noticed that 5-year old seeds of . gave a considerably higher proportion of phenotypic variants than fresh ones. De Vries explained this phenomenon by postulating a longer period of viability for those seeds whose hereditary constituti

ADJ

陶器

Dormancy: a Factor Affecting Seed Survival in the Soil,rocess of germinating — e.g. a dry seed in storage — is said to be dormant. However, more commonly — and more usefully — the term is used in a more restricted sense to indicate that the seed, although viable, will not germinate under conditions normally considered to be adequate for germination, viz

Clinch

Control mechanisms in the resting seed,ed is progressively inactivated, and early germination when seed metabolism becomes active again. The use of the term ‘resting’, when applied to plants and their organs, has been anything but consistent; in the present discussion the term will be applied in a general sense to seeds in which germinat

平

Feedback

Control mechanisms in the resting seed,s and their organs, has been anything but consistent; in the present discussion the term will be applied in a general sense to seeds in which germination is prevented either because they have an inadequate water content or because there is some metabolic block.

财政

Effects of Environment Before Harvesting on Viability,tions and there is usually a considerable discrepancy between the results of germination tests in the laboratory and the emergence of the seeds in the field, the discrepancy usually being greater the lower the per cent germination (for examples see Perry, 1967 and Austin, 1963).

Functional

lavish

D. I. Arnonaren Zuständen enthalten, sondern gewöhnlich ist es nötig, durch chemische Maßnahmen die Bestandteile erst in erkennbare und trennbare Formen überzuführen. Diese chemischen Maßnahmen sind die chemischen Reaktionen, und die Zusätze, die man benutzt, um aus dem Untersuchungsmaterial charakteristische Stoffe darzustellen, heißen Reagenzien.