OCR Text |
Show Carrier of Wilt Disease Recent investigations by plant pathologists pa-thologists of tho department of agriculture ag-riculture havo established that tho striped cucumber beetlo plays an important nnd direct part in spreading spread-ing tho bacteria of wilt of cucum-bors, cucum-bors, radons and squashes. In addition addi-tion tho experiments seem to show that tho hlbornntlng beetlo can car ry tho Infection from ono season to tho new plnnts of tho noxt year. Tho fixing of tho responsibility on this beetlo, long suspected of being n carrier ot wilt, gives an addition nl reason for controlling this pest of cucurbits. In tho experiments as roported In tho Journnl of Agricultural Resenrch tho Investigator grow cucumber vines In beetlo proof cages In two fields lti Long Island whero In 1914 nbout 7C per cent of tho cucumber vinos had been destroyed by wilt. Some of tho test plnnts woro thus kept nb-Bolutoly nb-Bolutoly freo from beettes, whllo beetles recently out of winter hibernating hiber-nating quarters were introduced purposely pur-posely Into olhor cages. Tho experiments established absolutely abso-lutely that the beetle carries wilt during tho growing season from Infected In-fected to other plants. In nil cages from which beetles woro oxcluded tho plants remained free from disease In both flo'ds although wilt Infected plants wero growing all nroun l tho cages. On tho other hand, wilt has found in tho cages only when tho striped cucumber beetle had gained access to tho plants. In ono cage, supposod to bo freo from beot'os, wilt wns observed Just starting on tho tip leaf of ono plant nt n point gnnwod by n beetlo. Careful senrch of this cogo disclosed n striped beet'o. After tho beetlo had been removed and tho ono wilted plnnt had been taken out, no furthor signs of tho dlseaso appeared In that cago. Tho cago experiments Indlcnto that wilt bacteria nro carried over tho winter by hlbornntlng beetles nnd nro Inoculated Into tho next crop of cucumber plnnts whon tho booties feed upon tho young leuvos. Tho results re-sults seom to Indlcnto, however that not n'l hibernating beetles carry tho dlseaso ovor tho wlntor but that only somo of thoso which presumably havo fed during tho provlous season upon wilted plants Infect tho noxt yenr's pluming. Theso facts woro established by placing In ccrtnln of tho cages hibernating beetles procured procur-ed boforo thoy had hod any opportunity opportun-ity to feed upon recontly diseased plants. A part of tho p'nnts gnawed by thoso booties boenmo Infected with wilt, while nearly 200 plants from which booties woro excluded remained remain-ed freo from tho (Hscqbo throughout the season. m Sj |