Vascular differentiation in the pear root
Author
Katherine EsauAuthor Affiliations
Katherine Esau was Assistant Professor of Botany and Assistant Botanist in the Experiment Station.Publication Information
Hilgardia 15(3):299-324. DOI:10.3733/hilg.v15n03p299. April 1943.
PDF of full article, Cite this article
Abstract
Abstract does not appear. First page follows.
Introduction
The present paper deals with the development of the root of Pyrus communis L., with special attention to the vascular tissues. Though considerable information is available on root structure of herbaceous plants (Hayward, 1938); (Esau, 1940),
only one rather complete account of tissue differentiation in a root of a woody species appears to exist in modern botanical literature (Hayward and Long, 1942). The need for such accounts in the teaching of plant anatomy, especially in agricultural institutions, is obvious.The present problem was selected also because of the writer’s interest in the differentiation of the phloem tissue in different organs of seed plants. Since many studies have been made on the phloem of roots of herbaceous plants (review by Esau, 1943), it seemed timely to add some data on the ontogeny of this tissue in a woody root.
Materials and Methods
The root material used in preparing the permanent slides and the photomicrographs was obtained from trees grown in a culture solution by the Plant Nutrition division at Berkeley. The material was killed in a formalin-acetic-alcohol fixing fluid and imbedded in paraffin after ordinary dehydration and clearing in mixtures of ethyl alcohol and xylene.
The roots grown in the culture solution were compared with soil grown roots from young trees 5 to 6 inches high grown from seeds of the Winter Nelis variety. The latter roots were examined in free-hand sections.
Literature Cited
Barghoorn Elso S. Jr. The ontogenetic development and phylogenetic specialization of rays in the xylem of dicotyledons. I. The primitive ray structure. Amer. Jour. Bot. 1940. 27(10):918-28. DOI: 10.2307/2436561 [CrossRef]
Esau K. Initial localization and subsequent spread of curly-top symptoms in the sugar beet. Hilgardia. 1935. 9(8):397-436. DOI: 10.3733/hilg.v09n08p395 [CrossRef]
Esau K. Ontogeny and structure of the phoem of tobacco. Hilgardia. 1938. 11(8):343-424. DOI: 10.3733/hilg.v11n08p343 [CrossRef]
Esau K. Development and structure of the phloem tissue. Bot. Rev. 1939. 5:373-432. DOI: 10.1007/BF02878295 [CrossRef]
Esau K. Developmental anatomy of the fleshy storage organ of Daucus carota. Hilgardia. 1940. 13(5):175-226. DOI: 10.3733/hilg.v13n05p175 [CrossRef]
Esau K. Phloem anatomy of tobacco affected with curly top and mosaic. Hilgardia. 1941. 13(8):437-90. DOI: 10.3733/hilg.v13n08p435 [CrossRef]
Esau K. Origin and development of primary vascular tissues in seed plants. Bot. Rev. 1943. 9:125-206. DOI: 10.1007/BF02872466 [CrossRef]
Foster A. S. Practical plant anatomy. 1942. New York, N. Y.: D. Van Nostrand Company, Inc. 155p.
Guttenberg H. von, Linsbauer K. Der primäre Bau der Angiospermenwurzel. Handbuch der Pflanzenanatomie 2. Abt. 3. Teil: Samenpflanzen. 1940. VIII: Berlin: Gebrüder Borntraeger. 369p. Lief. 39
Hayward H. The structure of economic plants. 1938. New York, N. Y.: The Macmillan Co. 674p.
Hayward H., Long E. M. The anatomy of the seedling and roots of the Valencia Orange. U. S. Dept. Agr. Tech. Bul. 1942. 786:1-31.
Lloyd F. E. Guayule (Parthenium argentatum Gray), a rubber plant of the Chihuahuan desert. Carnegie Inst. Wash. Pub. 1911. 139:1-213.
Russow E. Betrachtungen über das Leitbündel-und Grundgewebe aus vergleichend morphologischem und phylogenetischem Gesichtspunkt 1875. p.78. Schnakenburg’s Anstalt, Dorpat
Schüepp Otto, Linsbauer K. Meristeme. Handbuch der Pflanzenanatomie 1. Abt. 2. Teil: Histologie. 1926. IV: Berlin: Gebrüder Borntraeger. 114p. Lief. 16
Smith G. F., Kersten H. The relation between xylem thickenings in primary roots of Vicia faba seedlings and elongation, as shown by soft X-ray irradiation. Torrey Bot. Club Bul. 1942. 69:221-34. DOI: 10.2307/2481657 [CrossRef]
Also in this issue:
Interrelation of agricultural product markets and industrial developmentLight fruit set and leaf injury from boron deficiency in vineyards readily corrected when identified
Studies on self- and cross-pollination of olives under varying temperature conditions
Shipping methods used for fresh cut flowers evaluated in transcontinental trials
Surface irrigation water deliveries and costs in the San Joaquin Valley cotton area
Effects of tillage and fertilizers on use of water and soil salinity in irrigated orange orchard at Riverside
Test crop on acid soil indicates manganese toxicity may be aggravated by nitrogen
Feeding trials with dairy cows show DDT detectable in milk is proportional to DDT in daily feed
Low-concentrate rations for fattening lambs tested in two feeding trials
Synthesis of some plant pigments
Progress toward control of brucellosis
Changes in composition of milk from cows going dry
Vitamin B and body storage of chemical energy
Synthesis of fatty acids in plants
Infiltration and leaching of saline irrigation waters
Plant breeding of lima beans for nematode resistance
Tomato varieties resistant to tomato russet mite
Resistance to spider mites in cotton
Ontogeny of the vascular bundle in Zea Mays