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991.
W. L. Greenhill 《Grass and Forage Science》1964,19(2):231-236
The release of the plant-cell juices is a prerequisite for a lactic-acid fermentation in silage. Investigations with plant material at different moisture contents have indicated that above about 2 g water per g dry matter sufficient juice is released from properly ensiled material to permit the onset of fermentation; below this moisture content lactic-acid production is delayed, if not prevented.
When material of suitable moisture content is ensiled at a temperature of 25°C, the onset of fermentation is somewhat slower than at 40°C. However, within these limits, the temperature is not critical, provided that the silage is completely sealed to exclude air. The infiltration of even small amounts of fresh air delays the release of the juices and, especially at the lower temperatures, often results in an undesirable fermentation.
A number of miscellaneous treatments, designed to hasten the release of the juices, failed to show any advantages in small-scale tests. 相似文献
When material of suitable moisture content is ensiled at a temperature of 25°C, the onset of fermentation is somewhat slower than at 40°C. However, within these limits, the temperature is not critical, provided that the silage is completely sealed to exclude air. The infiltration of even small amounts of fresh air delays the release of the juices and, especially at the lower temperatures, often results in an undesirable fermentation.
A number of miscellaneous treatments, designed to hasten the release of the juices, failed to show any advantages in small-scale tests. 相似文献
992.
993.
M. Postner 《Forstwissenschaftliches Centralblatt》1964,83(1-2):33-38
Ohne Zusammenfassung 相似文献
994.
H. -H. Dietrichs und E. Schaich 《Forstwissenschaftliches Centralblatt》1964,83(7-8):212-222
Ohne Zusammenfassung 相似文献
995.
This paper traces the history of silvicultural management inthe New Forest prior to the establishment of the first plantationsdevoted solely to the production of oak for shipbuilding inthe early eighteenth century, and considers the origin of thepresent structure of the unenclosed woodlands of the Forest. 相似文献
996.
W. Zwölfer 《Forstwissenschaftliches Centralblatt》1964,83(1-2):63-64
Ohne Zusammenfassung 相似文献
997.
J. Ruinard 《Euphytica》1964,13(1):19-23
In a previous publication about the selection of cacao in West New Guinea, directions have been given on the production determination of individual trees. It was tacitly assumed that the pod weight of a given tree, although variable, would not change systematically with time. However, new data brought to light that this assumption was wrong. It was established that during the main harvest the average pod weight was considerably lower than during the remaining months. But as these changes of weight appeared to have no influence on the quotient pulp weight/pod weight, the method of production determination mentioned needs no revision.Present address: University of Science and Technology, Kumasi, Ghana. 相似文献
998.
H. P. Beukema 《Euphytica》1964,13(3):229-235
In breeding for resistance to stem mottle in potatoes there is a need for a rapid testing and selection method. Following the method normally used with X- and Y-virus, seedlings in the cotyledon stage and young plants of potatoes were inoculated with the stem mottle virus (= rattle virus). In this way it seems possible to test and to select young seedlings for resistance. In addition it is possible to establish rapidly the resistance of known potato varieties and progenitors with the air of young plants. 相似文献
999.
E. Assmann 《Forstwissenschaftliches Centralblatt》1965,84(5-6):193-194
Ohne Zusammenfassung 相似文献
1000.
J. N. Köstler 《Forstwissenschaftliches Centralblatt》1965,84(1-2):64-65
Ohne Zusammenfassung 相似文献