Contribution to the Symposium on The Trend of Progress," to be held during the Annual Meeting o f the Society in Exeter on July 13, 1939, at a session organized by the Microbiological Panel)
As mankind is ultimately dependent for food and energy 011 the green plant, pliint pathology is a scicncc of primc importance. Its aim is tlic production of crops of thc quiintity iind quality required, a task whicli may bc described as growing hcaltliy crops. It is axiomatic, thcrcforc, that plant piitliology must include the study of soil and climatic conditions in relation to pliint growth. Indccd thc earlier plant pat~liologists nttributcd most crop failures, tlic blights and blnstings, to uiifavourublc wcat,licr or wrong nutrition. Sonic 90 years ago, howevcr, t h botanist dc Uary recoguizcd that disciise in p1ant.s may bc caused by fiingi iind, to this day, plant pathology and applied niycology arc often used as syiionyuious ternis. The tmiid of pliint pithology is now away from mycology or riithcr, thc sliarc of niycology in thc trainiiig of thc plant pnthologist, t,liough nlways great, is bcconiing less conspicuous. I'hc raising of vrrrictics of crop plant resistant to unfavournblc soil, cliniatic or biological ngcncies ; tlic study of thc elfects of soil iind nutrient coiidit.ioiis on pliint growtli ; thc elucidiition of the mcchaiiisni of piirasitisni which ultimately will be intcrprctctl in biocficiniciil ternis ; such lire t,lic niorc iniportiint of t,Iic suhjects which slinrc, with mycology, in the build-up of t.lie pliint pithologist. Tlic cstreniist could torlily liliikc 11 good ciisc iigiiiIist tltc policy of tlic rccruitnient of titlvisory and rcsciircli worlrcrs ill pliint pithology froin tlic riinks of purc ciitoiiiology and ~nycology, but lie woultl linvc to igiiore a conscrviitivc rcluctnncc to cliiingc nnnies iind titles to conform to dcvclopnicnt. Tlic greater piirt of yliytopatliologiciil research tcnds niorc iiiid niorc to bc carricd out by tccuns of workcrs conipriscd of niycologist, cntoiiiologist., chcinist, physiologist, breeder, iintl thc priictical agriculturist. But adhcrencc to tlic pracbicc of ciilliiig thc plant piit,liologist ii niycologist Iiiis-given a scinblaiicc of truth to opinions, latcly iiircd in tlic semi-popular press tliiit pliint pithology is proceeding on wrong lines. !l'Iiesc opinions iirc bnscd 011 tlic tlicsis ndvocntcd, in particuliir, by Sir Albert I-Iowiirdl tliiit tliseiisc and pests iirc but indicators of iniproper nutrition. 'l'hcrctbrc, it is iirgucd, tlic pnthologist ~liould turn niorc to prwticiil ngriculturc ; that iiiodcrn Incthorls of plniit protection, cspccinlly tliosc inrolvilig thc use of intiecticiilcs iiiid fiingicitlcs, iirc rndicully unsound " iind rcnioyc tlic Censors which Iiiiturc hue provjdetl for kccping our ngriculturc up to tlic iiiiirk," It sccnis that tflic rcnicdics to bc substituted tire thc introduction of resistniit viirictics of crop plnnt iind tlic miiintoniincc of growtali conditions cncournying rcsirittrncc.