38 



PLASMODIOPHOHALES 



it as representative of a new genus, but as Cook 

 pointed out. there are no good reasons for introduc- 

 ing a new genus until more is known about the life 

 history of this species. It is accordingly retained 

 provisionally in Tetramyia. Maire and Tisons cyto- 

 logical study, nonetheless, indicates its similarity to 

 T. parasitica in the type of vegetative nuclear divi- 

 sion and the presence of centrosomes and astral rays. 

 The effects of this species on the host are striking. 

 According to Molliard. the parenchyma cells of the 

 stem and flowering stalk are greatly hypertrophied 

 and divide irregularly, while development of the 

 sclerenchyma is inhibited Likewise the flowers in an 

 infected region are sterilized. The infected cells may 

 enlarge to four times their normal diameter, while 

 their nuclei become enormous and deformed (fig. 

 20 j. The nucleoli also increase markedly in size and 

 become deeply basophyllic. At the same time nu- 

 merous deep-staining, chromosome-like chromatic 

 bodies develop in the nuclear cavity. Furthermore, 

 infected cells may often become multinucleate (fig. 

 19) as the result of amitosis. according to Maire and 

 Tison. The nuclei of adjacent cells may also become 

 enlarged and deformed. The presence of the parasite 

 further stimulates starch formation in the cells sur- 

 rounding infected regions. 



T. ELAEAGNI Yendo and Takase. 1933. BulL Sericult 

 Silk — Ind. Japan 4, no. 3: 5. 



Plasmodium inter- and intracellular, segmenting 

 into uninucleate spore mother cells which divide 

 twice to form tetrads of resting spores. Amoebae 

 formed from germinating resting spores. .Sporangia 

 and zoospores unknown. 



In the roots of Elaeaf/nui multiflora in Japan. 



This species causes tubercles or nodules which in 

 exceptional cases may attain the size of a man's fist 

 on old trees. The parasite occurs most abundantly in 

 the cortex and causes marked hypertrophy of the in- 

 fected cells as well as enlargement and distortion of 

 the nuclei. Yendo and Takase found that the percent- 

 age of nitrogen in the nodules was almost twice that 

 of the normal cortex, and for this reason they be- 

 lieved that there is a definite symbiotic relationship 

 between host and parasite. 



So little is known about this species that its valid- 

 itv as a member of the Plasmodiophoraceae is very 

 doubtful. Yendo and Takase reported that the Plas- 

 modium spreads over the host cells and fills the in- 

 tercellular spaces. Furthermore, the resting spores 

 are said to be capable of forming fine, curled, non- 

 septate, branched germ tubes or filaments instead of 

 amoebae. The formation of germ tubes suggests that 

 Yendo and Takase may have had spores of another 

 fungus at hand. 



ADDITIOXAL BIBLIOGRAPHY: TETEA.MVXA 



Cook. W. R. I. \9%2. Honp Kong Nat. Suppl. no. 1: 38. 



■ -. 1933. .\rch. Protistk. 80: :?16. 



Maire, R., and \. Tison. 1910. C. R. .\cad. Sci. Paris 50: 



1768. 

 .Schwartz. E. J. 1911. .\nn. Bot. 35: 79+. 

 Winge, O. 1913. .\rk. f. Bot. 13, no. 9: 36. 



PLATE O 

 Tetramyxa para»itiea 



Fig. 1. Galls on stems of Rvppia rottelhita. Goebel, I.e.; 

 Maire and Tison, '11. 



Fig. 3. Multinucleate plasmodium surrounding host nu- 

 cleus. Maire and Tison, I.e. 



Fig. 3. Plasmodium consisting of two multinucleate me- 

 ronts which appear to be fusing: nuclei dividing in one and 

 at rest in the other. Maire and Tison. I.e. 



Fig. i. Division of infected cell by which the meronts 

 have been passively divided and distributed. Maire and 

 Tison, I.e. 



Fig. 5. Equatorial ring stage of "promitosis'' in which 

 distinct chromosomes are evident. Maire and Tison, I.e. 



Fig. 6. .\naphases of same. Maire and Tison, I.e. 



Fig. 7. Plasmodium becoming parietal and cleaving into 

 uninucleate spore-mother cells or sporonts. Centrosomes 

 and astral rays present at poles of some nuclei. Maire and 

 Tison. I.e. 



Fig. 8. 9. Prophases of meiosis in sporonts. Maire and 

 Tison, I.e. 



Fig. 10. Equatorial plate stage of first meiotic division. 

 Maire and Tison, I.e. 



Fig. 11. Binucleate sporont with conspicuous astral rays. 

 Maire and Tison, I.e. 



Fig. 13. Equatorial plate stage of second meiotic divi- 

 sion. Maire and Tison, I.e. 



Fig. 13. Cleavage into tetrads. 



Fig. 14. Tetrad of resting spores. 



Fig. 15. Enlarged host cell with resting spores isolated 

 and single, in linear series, in diads. triads and tetrads. 

 Large resting spores binucleate. Maire and Tison, I.e. 



Fig. 16. Four resting spores in linear series. Goebel, I.e. 



Tetramyxa Tri{/lochinit 



Fig. 17. Galls on Triglochin palu»tre caused by T. Tri- 

 glochinh. Maire and Tison, I.e. 



Fig. 18. Enlarged host cell with spherical multinucleate 

 and fusiform uninucleate meronts. Maire and Tison, I.e. 



Fig. 19. Enlarged host cell with uninucleate meronts in 

 vacuoles. Host cell tetranucleate: nuclei with numerous 

 densely chromatic bodies. Maire and Tison. I.e. 



Fig. 30. \n enlarged, deformed host nucleus. Maire and 

 Tison, Lc. 



Fig. 31. Uninucleate fusiform meronts. Maire and Tison, 

 I.e. 



Fig. 22-2i. Equatorial plate, anaphase and telophase 

 stages of "promitosis." 



Fig. io, 36. Bi- and multinucleate thalli. Maire and 

 Tison, I.e. 



Oetomyra Arhlyae 



Fig. 37. Habit sketch of Achlya glomerata showing 

 effects of parasite on the hvphae. Couch, et al.. '39. 



Fig. 38. Early infection stage showing large parasite nu- 

 cleus in host cell. 



Fig. 29. Binucleate thallus surrounded by host proto- 

 plasm: nuclei dividing "promitotically." 



Fig. 30. Large plasmodium in a vacuolate area of hyphal 

 tip. 



Fig. 31. Sporangiosorus of nearly mature zoosporangia. 



Fig. 33. Zoosporangia with emerging zoospores. 



Fig. 33. 34. Biflagellate heteroeont zoospores. 



Fig. 35. Zoospore killed in osmic acid fumes and stained 

 with gentian violet. Drawn from photomicrograph. 



Fig. 36. Large tetraflagellate zoospore. 



Fig. 37. Sorus of resting spores. 



Fig. 38-40. Groups of resting spores. 



