ROOT KNOT NEMATODE INFESTATION 7 



Arrangement 



In the list of plant species and varieties (beginning on p. 11), botani- 

 cal synonyms are given only where these names have been used in one 

 or more of the publications cited. Common names used in the publi- 

 cations cited are given in addition to the standardized common names. 



Names of cultural varieties that could not be checked are cited 

 in quotation marks. 



Where the common name of a plant is included in a citation, it 

 indicates that the botanical name was not reported by the author 

 quoted. The common name is not always repeated in cases where 

 there is no possibility of mistaking the species. 



Because the available material is un standardized and often con- 

 tradictory, an authority is cited for every statement, giving all data 

 that might affect the conclusions if found in his report. The value of 

 any statement depends obviously on the experience of its author 

 and on his use of terms. A minimum of editorial interpretation has 

 been added; where this is given it follows the citation, separated from 

 it only by brackets. Brackets are used also to indicate supple- 

 mentary unpublished data of the investigator cited. 



Where possible the geographical location is given for each observa- 

 tion. It has never been determined whether the geographical differ- 

 ences in reaction of a given plant are caused by differences in cultural 

 conditions, soil type, climate, nematode population, plant strain, or 

 in the observer's basis of estimation. Latitude is less important to 

 greenhouse experiments than to field observations, but authors have 

 not always indicated the growth conditions of the plants noted. 



All statements have presumably been traced back to the original 

 observer except where an indirect source is credited. Because an 

 author's original observations are not always distinguishable from his 

 quotations of other publications, doubtful citations are included, but 

 are indicated by the words "listed as . . ."or else by a question 

 mark following the geographical information. Care has been taken 

 to ascertain that every report refers to the root knot nematode, and 

 this may be assumed for all citations not otherwise indicated, though 

 subject to the confusion and inaccuracies of the literature, where even 

 scientific names have been misapplied. 



Capital letters in parentheses follow certain plant names to give 

 supplementary information, as follows: 



(C) marks the first plant of a genus for which complete data have been cited. 

 The available information may or may not be adequate to indicate the true 

 status of these plants, but every known report is included. 



(M) marks the first plant of a genus that includes additional species that are 

 conspicuously more susceptible than those listed. 



(N) marks a species on which infestation has been observed by members of the 

 Division of Nematology. It is thus an evidence of one or more additional in- 

 stances of infestation, though not necessarily of heavy infestation, for which 

 individual citations are not always given. 



(S) marks a species that is usually highly susceptible, although either the species 

 or some of its varieties have been reported resistant. 



The presence or absence of the key letters (C) and (N) gives infor- 

 mation on the completeness of the citations about particular plants, 

 whereas (M) and (S) are used as warnings that this publication is not 

 primarily a list of resistant plants. 



