Plant Breeding
the science of eight of Saturn, four of Uranus, and one of Neptune. The planets Mercury and Venus, being nearer than the Earth to the Sun, are called inferior planets; the others, hers, being more distant, are producing new or improved species of termed superior. Another classification plants by a process of crossing or selecis sometimes adopted, that into intra- tion. The tendency of all plants is to and extra-asteroidal planets; that is, reproduce plants possessing all their own those nearer and those more remote characteristics, but changes and improvefrom the sun than the asteroids. Under the first are included, Mercury, Venus, the Earth, and Mars, all of which are comparatively small, while the others, Jupiter, Saturn, Uranus,.and Neptune, are the giants of the system. For instance, the Earth is 7,918 miles in diamements are brought about by various methods.
The simplest method of the selection process is to save the seeds of only those plants which possess in a marked degree the desired characteristics. This process is usually slow and uncertain, PLANT and fertilization through a natural or and of Lancaster, known as the parties artificial transfer of pollen is often resorted to. Improvement to various grains, sugar beets, potatoes, etc., has been accomplished by emasculating selected specimens. When the stigma of these are ripe, pollen from other selected plants is applied, and the plants are kept under a gauze hood to prevent accidental contact with other pollen. The seeds of these specially treated specimens are col- PLANTATION of the Red and White Rose.
PLANTAGINACEÆ, or PLATAG- INEÆ, ribworts; an order of perigynous exogens, alliance Cortusales. Herbaceous plants with or without a stem.
Leaves flat and ribbed or taper and fleshy. Flowers in spikes, solitary.
Distribution world-wide: known genera three, species over 200. lected, and used for future breeding. PLANTAGO, plantain or ribgrass; the Artificial asexual methods, of which grafting is the most common, are the aceæ; herbs, with bisexual flowers. simplest form of plant breeding, and though perhaps the surest of the methods, are not likely to produce the strongest plants. A large number of experiments must be made, and a great amount of tedious work done before a new type produced that can be introduced commercially. Not all the specimens are improvements, for plants are just as likely to degenerate under the process as they are to improve.
These simple rules are used by many of the leading plant breeders:
Well developed seedlings produce the best plants; small leaves usually mean undersized fruit; pale leaves mean pale fruit; great productiveness does not go with earliness. typical genus of the order Plantagin- Mucilaginous and astringent. Known species about 48. In India the leaves of P. major are applied to bruises. P. coronopus is diuretic. Demulcent drinks can be made from P. psyllium, P. arenaria, and P. cynops. The seeds of P. psyllium and P. ispaghula, treated with India in diarrhea, dysentery, catarrh, gonorrhea, and nephritic diseases. P. amplexicaulis is used in India in phthisis, snake poison, intermittent fever, and as an external application in ophthalmia.
Soda is obtained in Egypt from P. squarrosa.