摘要:

SUMMARYTracheary elements with well‐developed cell wall thickenings and containing large amounts of storage material were occasionally found in hypocotyls of the cucumber of certain ages. The storage material, consisting of protein bodies, lipid bodies, and starch grains, was closely packed. The few cell organelles present were disintegrated.The ultrastructure of the aberrant tracheary elements and procambium elements likely to differentiate into them is described.The storage material must be regarded as newly formed from material dissolved in neighbouring cells. It is postulated that activities necessary for differentiation suppress the deposition of storage material while the capacity of the cell to store material remains for some time after the termination of the dormancy period of the seed. The new formation of storage material would occur in procambium elements in which differentiation related processes were initiated before the onset of dormanc

ISSN:0044-5983    

DOI:10.1111/j.1438-8677.1976.tb01063.x

年代:1976

数据来源: WILEY

摘要:

SUMMARYThe action spectrum for light‐induced germination of thermo‐dormant lettuce seeds in shifted to longer wavelengths in comparison to the action spectrum for far‐red dormant

ISSN:0044-5983    

DOI:10.1111/j.1438-8677.1976.tb01064.x

年代:1976

数据来源: WILEY

摘要:

SUMMARYThe metabolism of zeatin‐8‐14C in detached inflorescence stalks ofYucca flaccidahas been studied. The compound has been fed either through the xylem or has been added directly to phloem exudate.The results strongly indicate that after uptake by the stalk zeatin is converted into the corresponding mono‐, di‐ and tri‐phosphate ribonucleotides, whereas incubation of phloem sap with zeatin only resulted in the formation of the mono‐rib

ISSN:0044-5983    

DOI:10.1111/j.1438-8677.1976.tb01065.x

年代:1976

数据来源: WILEY

摘要:

SUMMARYParticle size, morphology and lipid composition of the latex particle fractions of 18Hoya, 3Dischidiaand 5Euphorbiaspecies were investigated. Of these latices only two showed in vitro triterpene biosynthesis.Some aspects of particle biosynthesis are discussed.

ISSN:0044-5983    

DOI:10.1111/j.1438-8677.1976.tb01066.x

年代:1976

数据来源: WILEY

摘要:

SUMMARYChrysophyceae from the northern region of the Netherlands have been examined by electron microscopy. Twenty‐eight species, varieties and forms were found. Twenty‐two of these have not previously been recorded for the Netherlands. In addition, one new variety is descri

ISSN:0044-5983    

DOI:10.1111/j.1438-8677.1976.tb01067.x

年代:1976

数据来源: WILEY

ISSN:0044-5983    

DOI:10.1111/j.1438-8677.1976.tb01068.x

年代:1976

数据来源: WILEY