CITKUS MELANOSE AND ITS CONTROL 
Table 1. — Range of infection on various rutaceous plants by the melanose 
fungus Phomopsis citri Fawcett, as indicated by artificial inoculations and 
general observations — Continued 
Botanical name 
Common or variety name 
Range of infection 
ROUND OE SWEET ORANGE GROUP 
Citrus sinensis Osbeck 
Chamoudi orange 
Severe to very severe, 
Do- 
Florida seedling orange 
but distinctly less so 
than grapefruit. 
Do. 
Do 
E nter prise orange 
Do. 
Do 
Homosassa orange 
Do. 
Do 
Jaffa orange 
Do. 
Do- 
Do. 
Do 
Lue orange 
Do. 
Do 
Maltese orange.. 
Do. 
Do- 
Do. 
Do 
Do. 
Do 
Do. 
Do 
Pineapple orange 
Do. 
Do 
Ruby orange .. ... . 
Do. 
Do 
Do. 
Do 
Do. 
Do . 
Washington Navel orange... 
Do. 
KID-GLOVE ORANGE GROUP 
Citrus nobilis Lour . 
Slightly less than sweet 
Citrus nobilis deliciosa Sw 
orange. 
Do. 
Do 
Do. 
Do 
Dancy tangerine . . 
Do. 
Do 
Do. 
Do 
Do. 
Citrus nobilis unshin Sw .. 
Do. 
Citrus mitis Blanco.. 
Calamondin 
Do. 
Citrus (Papeda) hystrix DC . 
Pointed-leaf Papeda— 
Susceptible. 
Do _. 
Round-leaf Papeda ... 
Do. 
Citr us webber i Webster ._ _. 
Do. 
Microcitrus australasica Sw 
No infection observed. 
The designation of degree of infection in Table 1 follows as closely 
as possible the scale used elsewhere in this bulletin for recording 
results of the inoculation and spraying experiments. 
From this table it is seen that melanose develops on a very wide 
range of plants in family Rutaceae, subfamily Citratae. Of the 34 
species under observation, the disease developed on all except 10, 
and these apparently immune members are scattered quite well 
throughout the entire range. Toddalia lanceolata Lam., the only 
form under study in subfamily Toddalioideae, is also apparently 
immune. 
Triphasia trifoliata and Sev&rinia buxifolia are attacked very 
slightly, and the citrons, kid-glove oranges, round oranges, limes, 
lemons, sour oranges, grapefruit, and kumquats are affected in about 
the order named. Among the grapefruits the Royal and Triumph 
varieties, as a rule, are less severely blemished than the average com- 
mercial grapefruit. These two varieties are supposed to be hybrids 
between grapefruit and orange. 
According to the observations of the writers, the greater suscepti- 
bility of grapefruit to infection is shown by the fact that it is much 
easier to find melanose scars on leaves and small green grapefruits 
than on orange fruits and leaves of the same age, and that the 
degree of injury is almost always more severe on grapefruits. Fur- 
thermore, the causal organism produces pycnidia in nature more 
