462 



NEMATODE ROOT GALL DISEASES. 



Of the inniiy iliHonHOs, noiiiatode 

 root Kiills ofton prove ii Kri'Ht ilraw- 

 back to pliiiit llfo. Kvery Krower and 

 partlnilurly tin- Kunlcnor. tlio florist 

 and the trmkcr ari> ispcclally Inti'r 

 estpd In this i-lass of plant allniGiit. Bo- 

 cause of Its Krcat economic linportanco 

 It will not he out of place to briefly 

 trace the history of root knot. Nema- 

 todes are probably of lOuropean origin. 

 In 1890 great losses are recorded on 

 the Continent, the sugar beet then was 

 almost wiped out by severe nematode 

 outbreaks. In ISflC the trouble sudden. 

 ly aiM'eared in the Ignited States. The 

 first attack then being recorded on 

 roses grown under glass; it being in- 

 troduced with imported stock. Ever 

 since that date the pest has spread 

 over large areas In many states. Green- 

 house plants have a harder struggle 

 since the conditions under which they 

 grow renders them weak and less re- 

 sistant to diseases. What is true with 

 Indoor plants is also true for vegeta- 

 ble crops of the trucker and gardener. 

 There, too. although the plants receive 

 the benefit of outdoor air, they are 

 nevertheless weakened because of the 

 excessive use of manure or commer- 

 cial fertilizer all of which is conducive 

 to rapid growth. Intensive culture then 

 Invariably results In weaker plants. 

 These then are the reasons why green- 

 house and garden plants are greatly 

 subjected to root gall injury as well as 

 to numerous other diseases. 



Symptoms of Root Galls. 



Many a grower who loses heavily 

 from this trouble hardly suspects its 

 presence simply because he has not 

 learned to recognize it in its initial 

 stage. Beyond a yellowing and dwarf- 

 ing of the affected plant there are no 

 outward definite symptoms of the dis- 

 ease. Diseased plants cease growing, 

 become yellow, languid, and may re- 

 main in this condition the entire grow- 

 ing season. This is usually true for 

 affected roses, begonias, violets, sweet 

 peas, and many other plants. With 

 greenhouse cucumbers affected plants 

 suddenly collapse and die without fur- 

 ther warning. Upon pulling out such 

 plants the seat of the trouble will be 

 located at the roots. In size, root galls 

 vary greatly with the individual host. 

 On the roots of affected carnation 

 plants the knots are irregular as to 

 size and shape, varying from a six- 

 teenth to half an inch or more in di- 

 ameter: and from spherical or oval 

 with smoothish surfaces to rough 

 lumpy swellings. With sweet peas 

 the knots are often tlie size of a pea 

 seed and are mistaken for the true 

 legume nodules of that plant. Witli 

 roses, begonias and tomatoes the galls 

 are fairly large. With lettuce the 

 knots are small. Growers who notice 

 a languid growth should at once pull 

 out a few plants in order to make sure 

 of the presence of the disease in their 

 soil. 



Cause of Root Galls. 



The trouble is induced by a parasite 

 commonly known as eel worm or nem- 

 atode. Eel worm is a true worm, be- 

 longing to the same animal group as 

 the common fish worm, the tape worm 

 the trichinia of the pork, and the vine- 

 agre worm. Nematodes are very slen- 

 der, minute pearly white, glistening 

 worms. As soon as the young hatch 



II II l(T I CM' \.T V ]{ !•: 



AN INGENIOUS ADVERTISING SCHEME. 



.April :i. 1915 



ItriiK BmnvN .\nu His Tami: Uihistkk. 



r. s m 



One of the cleverest advertising 

 stunts seen lately is one used by 

 liolgiano's seed store of Baltimore, Md. 

 It Is a tall, lanky, country chap, wind- 

 ing his way in and out llirou^h the 



downtown crowds closely followed by 

 a big rooster. The rooster does a num- 

 ber of amusing trii ks and the adver- 

 tising idea catches on with the crowds 

 everywhere. Rube carries a big grip- 

 sack upon whi<'h is Bolgiaun's .\rl 



from the (>ggs tliey i)ush their way In- 

 to the root of healthy plants in which 

 they settle. The presence of these 

 worms in the sound roots causes an 

 irritation whicli results in these swell- 

 ings or galls. -At first both sexes are 

 slender and hardly visible to the 

 naked eye. Soon, however, the female 

 increases in size as to be readily seen 

 by a good eye. At this stage the fe- 

 male is incapable of locomotion and 

 presents no more evidence of being 

 alive than a small seed. The male on 

 the other hand remains slender .-.nd 



Root G.\o.s of CARNATIONS 



active even upon reaching maturity. 

 Because of this activity it is able to 

 search the female and fertilize her. A 

 fertilized female further swells pre- 

 senting the appearance of a sack full of 

 eggs. Soon the mother dies and all 

 that remains is a cavity filled with 

 mature eggs. These hatch and the 

 young at once begin to travel to sound- 

 er portions of the plant root to renew 

 the life cycle, or they migrate back to 

 the soil searching for a new host. Be- 

 cause of the tender and minute nature 

 of eel worms they do not thrive well 

 in heavy lands. The soil best suited 

 for this pest Is the type of soli best 

 fitted for forcing house and truck 

 crops; namely, a light rich sandy loam. 



Damage Caused by Eel Worm. 

 Generally speaking losses are more 

 severe in the states where the winter 

 is mild than in colder climates where 

 nematode activity is confined to green- 

 house plants only. In the South, for 

 instance, certain areas have become so 

 infested with nematode that it is diffi- 

 cult if not impossible to grow certain 

 crops, particularly trucks. In Massa- 

 chusetts, on the other hand, the great- 

 est loss is experienced in the raising 

 of cucumbers and lettuce under glass. 

 In other northern states where indoor 

 vegetables are extensively grown, to- 

 matoes too are known to suffer heavily 

 from the nematode pest. In Kentucky 

 the disease has been severe on carna- 

 tions under glass. The same is true 

 for indoor roses and violets extensive- 

 ly grown in a number of states. With 

 violets particularly the attack is al- 

 most fatal to the plant either directly 

 or indirectly. Leaf curl in violets, for 

 instance, is due directly to a paralysis 

 of the root system. Leaf spot is in- 

 directly caused by insufficient nourish- 

 ment resulting in weak, poorly devel- 

 oped foliage which becomes easy prey 

 to fungus attacks. Cyclamens and be- 

 gonias are often greatly weakened by 



