SANEAMIENTO 1 OBJETO

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I n ducti on o f apothe ci a o f Drepanopeziza tremulae� D. popu li-albae a n d D. popu lorv� was attempted on n a tu ra l ly i nfected l eaves , l ea f di s cs a n d aga r .

( 1 ) NATURAL LY INFECTED L EAVES

Ove rseas co l l ecti o n s o f l eave s i n fected wi th the mi crocon i di al s ta tes o f M. brunnea� M. populi an d M. castagnei ( Tabl e 49 ) we re soaked in wate r an d p l a ced separate l y i n seal e d pl asti c con ta i n e rs wi th moi s t paper towe l s . The l eaves we re dark i n c ubate d a t 8 ° C fo r 10 days , 5 ° C for 2 0 days , 2 ° C fo r 3 days , 5 ° C fo r 20 days , 2 ° C fo r 3 days , 5 ° C fo r 20 days , 8 ° C fo r 1 0 days , l2 ° C fo r 5 days , 5 ° C fo r 5 days and fi n a l l y 8° C for

20 days . Leaves were exami ned for apo tneci a eve ry 1 5 days .

RESULTS

Apo theci a were fo rme d on l y on l e aves o f P. de ltoides re ce i ve d from Co l o ra do . Fo l l owi ng 60 days i n cubati on the a po the ci a (D. tremulae)

p ro duce d ma ture ascospo re s whi ch p ro ve d patho gen i c to l ea f d i s cs o f P . x euramer·icana cv. Rob u s ta . Ten days fol l owi n g i nocul a t i on the

con i di al s tate (M. brunnea) wa s fo rme d on the l ea f di s cs , thus con fi rmi n g the conne cti on between these two speci e s .

(2 1 LEAF D I SCS

In th ree experi men ts l eaf di s cs were i no c u l ate d wi th :

( i ) s i xteen i so l a tes o f M. brunnea recei ve d from th ro ugho u t the

wo rl d (Tab l e 5 0 } ,

( i i ) coni di a o f M. brunnea washed from l eave s o f P. de ltoide s

from Co

1

o ra do ,

( i i i ) i so l ates o f M. castagnei from Tu rkey an d I re l and .

ri men t A

Leaf di s cs ( 2 . 5 cm di am . } o f P . x euramericana cv . Robusta (40 d i s cs )

and P. nigra cv . Ital i ca t Aurea • (40 di s cs ) i n s e rte d a daxi a l s u rfa ce

uppermo s t i n to wel l s i n 2% wa te r agar we re i nocul ated wi th a one ml

s u s pen s i on o f coni di a ( a pprox. 6000 ) p re pa re d by bl e n d i n g 16 i so l a te s o f

M . brunnea ( Tabl e 50 } . The l ea f d i s cs we re dark i n cubated fo r 1 0 h a t 24 ° C

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TAB L E 49 : Ori g i n of natura l l y i n fecte d l ea ves used i n l abora to ry expe ri men ts to i n duce apo theci a

S oeci es Host Co l l ector Date

M. brunnea P a l me rs ton North , P. x euramericana Author 25/ 3/ 78- 79

NZ

11 _{Dubl i n , I re l an d P . x e?p'americana} F . _{o �} Ri o rda i n _{30/ 10/ 79} 11 Co l ora do , USA _P. cv . Roous ta x de ltoides T . E . H i n ds 30/ 1 0/ 79 M. castagnei Dub l i n , I re

1

an d P. a lba F . 0 ' Ri o rda i n 30/ 10/ 79

M. popu li 1 1 11 _{P . nigra}

CV . 1 1 30/ 10/ 79

I ta l i ca

11 _{Su rrey ,} Engl and _{P. nigra} cv . A . G . Bai l ey _{10/ 1 1/ 79}

I ta l i ca

TABL E 50 : I so l a tes of M. brunnea used i n expe t'i men ts to i n d uce apothe ci a on l e a f di s cs and a ga r .

I so

1

a te Hos t

Br 1 P. yunnanensis P a l me rs ton No rth , NZ

Br 3 P. fremontii cv. 6 1/48 P a l me rs ton North , NZ

Br 6 P. a lba P a l me rs ton No rth , NZ

Br 7 P. X euramericana CV . Fl e vo P a l me rs ton North , NZ

Br 8 P. x euramericana C V . NL 2 194 P a l mers ton North , NZ

Br 10 P . de l toides I l l i no i s , USA Br 1 1 P. de ltoides I l l i no i s , USA

Br 12 P. de ltoides I l l i noi s , USA

Br 1 3 P. de ltoides I owa , USA

Br 14 P. trichocarpa �1i nneso ta , USA

Br 1 5 P. de l toides C o l o ra do , USA

Br 16 P. x euramericana C V . Rob u s ta S u rrey , Engl and

Br 17 P. x euramericana C V . Rob u s ta Dubl i n , I re l and

Br 18 P. x euramericana Nancy , France

Br 19 P. x euramericana Hees , H o l l an d

. .

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the p ro ducti on of apo theci a the l ea f d i s cs we re then remo ved from agar an d hel d in sea l e d p l a s ti c con tai ne rs l i ne d w i th mo i s tened paper towel s . The con ta i ne rs we re dark i n cuba ted , a s for na tu ra l l y i n fecte d l ea Ves .

B

L�a f d i s cs .(2 . 5 .cm di am . ) of P. x euramericana cv .. Robusta (40 di s cs ) an d P. nigra cv . I ta l i ca 1 Au re a • (40 di s cs ) we re· i nocul a te d wi th a con i d i a l s u s pens i on p repared from l eaves of P. de Z toides ex. Co l ora do . Compa ti b l e ma ti n g s t ra i n s o f M. brunnea mus t have been pre se n t on th i s ma te ri a l s i n ce apo theci a had prev i o u s l y bee n i n duced on thes e l ea ve s . The i nocul a te d di scs were i n cubate d a s i n experi men t A to fi rs t ly i nd uce p roducti on of mi croconi di a an d then a po thec i a .

C

Forty l eaf di scs (2 . 5cm d i am . } of P. a Zba • tv1orocco • x P. nigra

Sempe rvi rens cv . t�a re g 2 vtere each i n ocul a te d wi th a one ml con i di a l

s us pen s i on ( approx . 6000 con i di a/ml ) prepare d by b l endi n g two i so l a tes o f

M. castagnei ( I rel an d & Turkey) . To i n duce mi crocon i di a l an d apo thec i a l

pro ducti on the l ea f di scs we re da rk i n cubated a s i n the p re vi o us experi men ts .

RESU LTS

Al though mi croconi di a were p ro duce d i n abun dance i n each expe ri men t , apo theci a (D. tremuZaeJ we re forme d on l y on l ea f di s cs

i n ocul a te d wi th con i di a o f M. brunnea from Co l orado . Apo the ci a \"e re fi rs t observe d 40 days fo l l owi n g i nocul a t i on and mature a s co s po re s a t 6 0 days . Apotheci a we re mo rpho l o g i cal l y s i mi l a r to thos e i n du ce d on n a t u ra l l y i n fecte d 1 e aves .

On l eaf di scs i nocul a te d w i th con i di a of M. brunnea (�xpe ri men ts A an d B ) n ume ro us spheri ca l , ra i se d cus h i on - l i ke s t roma ta l bodi es

deve l oped . Stroma ta s uperfi ci a l l y resembl e d i mma tu re apo theci a i n s ha pe an d s i ze me a s u ri ng 150 -200u i n di ame te r x 150-250u i n depth , a n d

exten de d 80- lOO u above the cuti c l e ( Fi g . 105 ) . Hov1e ver e l e c tron mi c ro­ s copy re vea l e d that s uch bodi es we re s t ructu ra l ly d i s ti n c t bei n g compo sed o f cl o s e l y packed , i so d i ame tri ca l , ova l to e l on ga te th i ck-wa l l e d cel l s

. con ta i n i n g many l i pi d g l obu l es and p l ugge d s ep tal po res ( Fi g . 106 ) , whe l�e a� i n apo the ci a the componen t ti s s ues ( e c tal , rr:e d u l l a ry e xci pul um , hypo thec i um ) were q u i te di sti nct an d vari o u s l y deve l o pe d . Wi t h further

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deve l opmen t of the s troma ta . mi cro con i di a and con i di a we re fo rme d w i th i n and on the s urface of s t roma tal ti s s ue , s uch con i di a were p a tho gen i c to l eaf di scs of P. x euramericana cv. Rob u s ta .

( 3 ) AGAR

Pl a tes of 15%V8 an d PC-10 we re i noc u l a te d wi th i so l a te s of M. brunnea an d M. castagnei used i n experi men ts A & B , an d w i th f�o l a tes from l eaves of P. de ltoides from Col ora do . P l a tes we re then sea l e d wi th pa rafi l m an d dark- i n c ubated ( as p rev i o u s l y ) to i n duce p ro du c ti on o f mi c rocon i d i a a n d apothe ci a .

RESULTS

Al though abundan t mi crocon i d i a we re pro duce d apotheci a we re n o t forme d .

Howeve r i so l a tes of M. brunnea fo rme d l a rge , e l eva ted b l ack l ea the ry s troma ti c bodi es mo rpho l o g i ca l l y s i mi l a r to those fo rme d on l ea f di.s cs ( experi me n ts B & C) .

C I N FLUENCE OF TEMP ERATURE ON DEVELOPMENT

In document TítuloFab Lab en A Coruña (página 166-170)