1138 EXPERIMENT STATTOTST EECOED. 



Report of the botanist for 1906, O. P. Clinton (Connecticut State Sta. Rpt. 

 1906, pt. 5, PI). SinSiiS, i)Is. 16). — The author reports on miscellaneous fungus 

 diseases, experiments to prevent onion brittle, the dry rot fungus, and tbe root 

 rot of tobacco. 



A number of diseases that were more or less injurious are briefly described, 

 and notes given on others which are either but recently recognized as occurring 

 in the State or which have only recently become of economic importance. 

 Among the latter class a description is given of an injury to the apple tree 

 caused by the joint effect of freezing and attacks of canker (Si)luvropsis 

 mal(jrum). A leaf scorch of beans which resembles in some respects a bac- 

 terial blight, but which fiiiled on examination to reveal either bacteria or fungi, 

 is briefly described, as are also a leaf spot of carnations, due to Alternaria sp., 

 the black rot of cauliflower (Pseudomonas cainpe.'<tri>^). and the black mold 

 of corn, caused by Chido.^porium zew. Notes are given on the bitter rot of the 

 grape and on the shelling of grapes which is usually attributed to some non- 

 parasitic causes. The author states that in connection with this disease he has 

 found the fruiting stages of a species of Macrophoma, but for the present the 

 fungus is considered to be a saprophyte. 



A yellowing of the leaves of oats, probably due to unfavorable weather condi- 

 tions, is briefly described, and an account is given of a physiological trouble of 

 peaches which resulted in an early defoliation of the trees. A i-oot injury or 

 rot of peonies, due to an undetermined cause, is said to have been quite serious, 

 and the author records its occurrence and will continue his studies upon it. 

 The leaf blight of pine due to Hijpoderma desnuizierii. pine rust, and winter 

 injury of white pine trees are briefly characterized. An account is given of the 

 wilt of raspberries, due to the fungus Leptosphirria coniotliyriiiin. This wilt 

 developed rather suddenly during wet weather in June, and an examination 

 showed the presence of the fungus at the base or underground portion of the 

 plant. Subsequent investigations showed that it also attacked the berries, 

 spreading from berry to berry in a cluster, and the author is of the opinion that 

 the infection in this case took place in the flowers and very young fruit, the 

 spores being carried by bees or other insects. Spraying experiments were con- 

 ducted for the control of this disease with but little effect. 



A number of diseases of tobacco are described, among them the bed rot 

 {Corticlurn vaguni solani), a bacterial canker, damping off. root rot caused by 

 Thielavia hasicola, and a stem rot. The bed rot, which was more or less trouble- 

 some, resembles in some respects the disease attributed to Sclerotinia in the 

 previous report (E. S. K., 18, p. 48). While considerable injury is done by the 

 Ithizoctonia stage of Corticium, the more common damping off agent in the 

 seed beds of the State is said to be Sclerotinia. For the control of the. stem 

 rot or damping off, the writer suggests sprinkling or spraying the tobacco beds 

 where the disease is present with a weak solution of formalin. If used at the 

 rate of 1 part to 1,500 of water the disease may be kept in check without serious 

 injury to the seedlings. The sterilization of the soil by soaking with stronger 

 solutions or by heat is also recommended. • 



A white spot of turnips, due to Cercosporella olho-niaciihuis:, a leaf spot of 

 Russian vetches caused by Ascocliijta vicia', and an anthracnose of violets attrib- 

 uted to Mursunia viola', are described. 



A series of experiments was carried on to prevent onion brittle, a description 

 of which is given in the previous report of the station (E. S. R., 18, p. 48). 

 The experiments for the control of this disease were carried on in a field where 

 it had first appeared 2 years before, and the treatments consisted of the appli- 

 cation of formalin at the rate of 1 to 240 parts of water, limoid at the rate of 

 700 lbs. per acre, sulphur and limoid, and a complete fertilizer. In each case 



