The Relation Of Some Rusts To The Physiology Of Their Hosts (1917) (Paperback)

Purchase of this book includes free trial access to www.million-books.com where you can read more than a million books for free. This is an OCR edition with typos. Excerpt from book: others were kept in the dark for various periods of time and were then brought into the light. Table III Effect of Light Upon the Development of Puccinia Coronata. Comparison of Plants Inoculated in Light and in Darkness Pot No.Time in LightTime in Darkad Period Time in LightIncubation PeriodRetardationC 17.10I diy4 days6 da 6 'ysII days: tion ys2 daysC 17.20. . . .I I4]: T' II2 "C 17.21 no infec C 17.225 5 5 9 9 9 C 17 21 3 ' 3 14 da '4 9 9 95 " 5 'C 17.24. 6 ' C 17. 25 C 17.26 C 17 27 C 17 28 5 1 7 8 8 .6 12 3 " C 17 20 9 9 11 no infe 9 da C 17. 10 . 1 5 C 17.11.. 2 " C'7-32 20 +: tion ys c 17.33 I 8 7 C 17.34 C 17-35 C 17-36 5 11 12 21 12 3 " 10 i I12 " 5 7 3 "Following this experiment, plants were inoculated in areas marked with India ink and covered with dark cylinders. After two days, the inoculated areas were sectioned and the sections treated with chloral hydrate and iodine. Mycelium was found in some of the inoculated areas, but had not developed to a very great extent. From these results it is evident that infection of Avena sativa by Puccinia coronala takes place in darkness as well as in light, although apparently the amount of infection is less in darkness. Puccinia Sorghi The first experiments upon the effect of light upon the development of Puccinia Sorghi were carried out in the same manner as with Puccinia coronata. The results obtained in these first experiments (Experiments 12-19) were not as clear cut as those obtained with the latter. Seven out of eleven plants which were in the dark three to eight days before being placed in the light had their incubation period lengthened one to two days. The other four had no retardation of their incubation period Four out of thirteen plants which were...