80 
(\-\RXE — Bromi Hot of Cilrus. 
all cases the results ■were negative. The fruit in 'water regularly 
Iteeanie attacked by various organisms. It is possible that these 
Avere secondary to and masked the infection l>y the 1)roAvu rot 
organism . 
Jii August. 1024. an experiment Avas made to infect tlie leaA^es 
of oj'auge trees in pots Avith a suspension of spores from a Avater 
culture from orange leaATS. 
19/8/24. — A Ijrancli of tree A sprayed Avith spore suspension ami 
])laced in open. Tree E. treated as in A. but placed in cold 
frame. C. small branch in lamp glass sprayed Avith suspension 
and closed Avith moist cotto}i aa'OoI. Placed in cold frame. D. 
as in 0., but Avith spore bearing leaf fragments placed on leaf. 
19/8/24 A. E. 0. D. 
14/9/24 + — — 
Infection folloAved a A’ery AATt AA*eek. It is difficult to account 
for the lengthy period ])receding infection. The disease is not 
kiioAvn ill tlie nursery in Avhich the AA'ork Avas done and seA’eral 
citrus trees groAving tliere Avere not affected. About 10^/c of the 
Sjirayed leaves Avere affected and none on the unsprayed l>ranches. 
As it Avas found readily possible to infect lea\'es in a AA'ater 
sus])eusion of sjiores the failure to secure infection on trees B., 0., 
I). Avas ])robably due to the difficulty of keeinng a film of moisture 
on the leaves except Avhen exposed to continuous AA^et AA'eather. 
During 1925 numerous attempts AA'ere made to secure infection. 
Tlie folloAving gawe positwe results: — 
(1). On 29tli May, 2 oranges and 2 lemons Avere placed in 
contact with naturally affected oranges in a jar. Xo lesions having 
a])peared the affected oranges AAa-re removed and replaced AA'ith more 
affected oranges on 12tli June. These AA’ere remoA’ed on 29th June, 
tlie original fruit remaining sound. On 1st July one orange de- 
veloped EroAvn Pot, the other fruit remaining sound. This result 
Avould a])])ear to indicate infection from spores formed on the 
affected fruit rather than mycelial infection. Controls remained 
sound . 
(2). On 29th May 2 oranges and 2 lemons AA’ere infected Avith 
diseased tissue from an affected orange. On 9th both oranges de- 
veloped BroAvn Rot. Lemons doA’cloped secondary rots. 
(8). Oti 16th June 1 orange and 1 lemon infected Avitli 
mycelium of P. hibeniaJis on potato dextrose agar isolated from orange 
fruit in 1924. On 25th orange developed BroAAui Rot. Lemon 
deA^eloped Penicilliunij etc . 
