A text-book of mycology and plant pathology . FlG. 80.—Roestelia, or aecia on apple leaf. {After Giddings and Berg, Bull. 257,Agric. Exper. Stat. Univ. Wise, July, 1915.) ducing numerous fasciations. The scia and pycnia of this fungusare on Myrica. Gymnosporangium globosum is remarkable in formingaecia on eighty-five different species of hawthorn, Cratagus, while its RUST FUNGI 211 (eliospores appear on irregular spheric swellings or excrescence onJunipenis virginiana. The mycelium of G. JHmperi-virgmiancB is annual, or biennial,producing globose swellings known as cedar apples on the leaves o
A text-book of mycology and plant pathology . FlG. 80.—Roestelia, or aecia on apple leaf. {After Giddings and Berg, Bull. 257,Agric. Exper. Stat. Univ. Wise, July, 1915.) ducing numerous fasciations. The scia and pycnia of this fungusare on Myrica. Gymnosporangium globosum is remarkable in formingaecia on eighty-five different species of hawthorn, Cratagus, while its RUST FUNGI 211 (eliospores appear on irregular spheric swellings or excrescence onJunipenis virginiana. The mycelium of G. JHmperi-virgmiancB is annual, or biennial,producing globose swellings known as cedar apples on the leaves of the. Fig. Sx.—Magnified view of apple rust roestelia, or aecia. {Afler Jone^ andBartholomew, Bull. 257, Agric. Exper. Stat. Univ. Wise, July, 1915.) red cedar, Juniperus virginiana. The cluster cups appear on the leavesof native species of apples (Mains). The most important publication dealing with this disease and giving 212 MYCOLOGY a copiousbibliography is one by Howard L. Reed and C. W. Crabill issuedas Technical Bulletin 9 (May, 1915) by the Virginia Agricultural Experi-ment Station. The 106 pages of text are devoted to a careful considera-tion of all aspects of the disease, which is prevalent throughout thegeographic range of the red cedar. The aecia are found on the appleand were originally described as Roestelia pyrata (Schw.) Thaxter,and frequently the apple stage is known as the Roestelia stage (). Infection of the leaves (Fig. 80) and fruit is only possibleduring their undeveloped condition and not all varieties of apple aresusceptible. Some are rust free. Such are Early
Size: 1435px × 1741px
Photo credit: © The Reading Room / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookcentury1900, bookdecade1910, bookidtextbook, booksubjectfungi
