24 MASS. EXPERIMENT STATION BULLETIN 428 



Chlorine Injury to Plants. (M. A. McKenzie and L. H. Jones.) Following 

 investigation of a tree trouble which proved to be of non-parasitic origin, the 

 possible involvement of escaping gas from a nearby chlorinator led to an investi- 

 gation of the effect of chlorine on woody plants. Available literature on chlorine 

 in relation to plants concerns chiefly chlorine in water used on soil in which plants 

 were growing. In conformity with common opinion, no injury was observed 

 when potted plants were watered with a mixture of chlorine and water applied 

 only to the soil. Injury^ did occur, however, when an equal quantity of the 

 same mixture was applied directl}' to the foliage. 



Resistance to Fusarium dianthi. Prill, et Del., the cause of a serious carnation 

 wilt disease. (E. F. Guba. VValtham.) The reaction of many standard varieties 

 of carnations {Dianthus caryophyllus L.) to F. dianthi has been determined by 

 artificial inoculation methods. Selected varieties showing a highly resistant reac- 

 tion to the branch rot fungus will be selfed and crossed for a similar analysis of 

 the progeny. The wilt-resisting seedlings will be carried to flowering in search of 

 types meeting commercial standards. 



Both Arasan (tetramethylthiuram disulfide) and Fermate (ferric dimethjl- 

 dithiocarbamate) in mixtures of 10 percent with 90 percent talc gave good control 

 of Fusarium wilt in the propagating sand when the basal end of artificially 

 inoculated cuttings was treated with the chemical dust before the cuttings were 

 planted A mixture of either of these fungicides with hormone dust in the ratio 

 of 10-90 respectively for a combined disease control and root inducing effect is 

 indicated. 



Considerable time was devoted to the preparation of a Station bulletin on the 

 subject of carnation wilt diseases and their control. 



Miscellaneous Studies. (E. F. Guba and E. V. Seeler, Jr., Waltham.) 

 Damping-Off Control with Seed-Borne Chemicals. As in previous years the 

 various dry chemical seed treatments were tested for their control of damping- 

 off of vegetable stands. The cold temperatures and abundant rainfall prevail- 

 ing throughout the vegetable seed sowing season were ideal for these tests. The 

 results will be compared with those of previous years and the preferred treat- 

 ments arranged in a chart or guide for market gardeners. 



DEPARTMENT OF CHEMISTRY 

 Walter S. Ritchie in Charge 



Studies on the Quantitative Estimation of Hemicelluloses. (Emmett Bennett.) 

 Hemicelluloses constitute one of the largest single group of substances in plant 

 material, but because of the association with other compounds and the hetero- 

 geneity of the substances, their determination is one of the least satisfactory to 

 make After making other preliminary tests utilizing the charge on the hemi- 

 cellulosic particle as a basis, it seems more advantageous to start with the holo- 

 cellulosic material. Preliminary experiments indicate that sodium chlorite can 

 be used effectively in preparing the holocellulosic fraction from non-woody plant 

 tissue for the quantitative estimation of hemicelluloses. This procedure, while 

 long, is simple, requires little attention, and eliminates other more tedious and 

 lengthy operations. The resulting product is substantially free of lignin and 

 contains the hemicelluloses. No statement concerning the actual quantitative 

 estimation is warranted at this time. 



'^Jones, L. H., and McKenzie. M. A. Chlorine gas injures trees. Arborist's News 9:89-90. 1944 

 (Mass. Agr. Expt. Sta. Contrib. 541). 



