THE SPIN^ACH ANTHRACKOSE 



177 



by sending out slender tubes, which may enter the leaves 

 through the breathing pores. 



The Spinach Anthracnose 



CoUetotrichum spinacece 



This is, perhaps, the most destructive of the spin- 

 ach diseases, as it grows rapidly, and, in consequence, 

 soon spreads over many plants. ^^The first indication 

 of its presence," writes Dr. Halsted, ^'is an indescriba- 

 ble moist appearance of the usually circular affected 



part ; followed by the appearance 

 of minute brown pustules, while at 

 the same time a gray color develops 

 and the diseased area becomes drv. 

 The anthracnose is shown in Fig. 

 76, where an affected leaf, much 

 reduced in size, is seen, with some 

 portions killed, by the fungus. No 

 particular part of the leaf is first 

 attacked, and, therefore, no two 

 leaves appear alike. In some cases 

 the largest leaves will be diseased, 

 in other plants only the younger 

 ones ; but sooner or later plants that 

 are affected will become entirelv 

 unfit for use. To test the rapidity 

 of the growth of the anthracnose, 

 healthy plants, grown in the labo- 

 ratory, were inoculated with the 

 spores, and in from five to seven days the spots sown 

 had become thoroughly diseased, and were bearing mul- 

 titudes of s]3ores." Spinach is also subject to attack by 

 a leaf-blight, a white smut and a black mold disease. 



Treatment for Spinach Diseases. — As already 

 stated, the diseases discussed above affect most severely 

 12 



FIG. 76. SPINACH LEAF 

 AFFECTED BY AN- 

 THRACNOSE. 



