Abstract
High yields of mesophyll protoplasts were obtained from leaves of corn (Zea mays L., inbred W64A). Many protoplasts survived a week in the dark in a simple osmoticum. Culture filtrate from Helminthosporium maydis race T at dilutions of 1:10,000 to 1:20,000 destroyed protoplasts with Texas male-sterile (T) cytoplasm. Substantial damage to protoplasts with nonmale-sterile (N) cytoplasm occurred only at a 1:20 dilution. High concentrations of partially purified H. maydis race T (HMT) toxin (32.5-130 μg dry weight/ml) did not reduce survival of protoplasts with N cytoplasm or C or S male-sterile cytoplasms after 6 days of exposure. Protoplasts with T or TRf (fertility restored) cytoplasm collapsed within 1 to 3 days after treatment with 0.13 μg of HMT toxin/ml, which was one-fifth the level causing 50% inhibition of T cytoplasm seedling root growth. Protoplasts with T cytoplasm which were washed after 30 minutes or more of exposure to HMT toxin also collapsed within a few days. Cultured W64A T protoplasts and freshly isolated protoplasts from inbreds C103 and Mo17 with T cytoplasm were less sensitive to HMT toxin than freshly isolated W64A T protoplasts. Toxin-treated protoplasts survived longer in the light than in the dark. The sensitivity and specificity of the system described will facilitate physiological, ultrastructural, and genetic studies of toxin action.
Full text
PDF
Images in this article
Selected References
These references are in PubMed. This may not be the complete list of references from this article.
- Aldrich H. C., Gracen V. E., York D., Earle E. D., Yoder O. C. Ultrastructural effects of Helminthosporium maydis race T toxin on mitochondria of corn roots and protoplasts. Tissue Cell. 1977;9(1):167–177. doi: 10.1016/0040-8166(77)90057-x. [DOI] [PubMed] [Google Scholar]
- Arntzen C. J., Haugh M. F., Bobick S. Induction of Stomatal Closure by Helminthosporium maydis Pathotoxin. Plant Physiol. 1973 Dec;52(6):569–574. doi: 10.1104/pp.52.6.569. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Beier H., Bruening G. The use of an abrasive in the isolation of cowpea leaf protoplasts which support the multiplication of cowpea mosaic virus. Virology. 1975 Mar;64(1):272–276. doi: 10.1016/0042-6822(75)90099-9. [DOI] [PubMed] [Google Scholar]
- Frick H., Bauman L. F., Nicholson R. L., Hodges T. K. Influence of Helminthosporium maydis, Race T, Toxin on Potassium Uptake in Maize Roots: II. Sensitivity of Development of the Augmented Uptake Potential to Toxin and Inhibitors of Protein Synthesis. Plant Physiol. 1977 Jan;59(1):103–106. doi: 10.1104/pp.59.1.103. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Gamborg O. L. The effects of amino acids and ammonium on the growth of plant cells in suspension culture. Plant Physiol. 1970 Apr;45(4):372–375. doi: 10.1104/pp.45.4.372. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Kanai R., Edwards G. E. Separation of mesophyll protoplasts and bundle sheath cells from maize leaves for photosynthetic studies. Plant Physiol. 1973 Jun;51(6):1133–1137. doi: 10.1104/pp.51.6.1133. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Karr A. L., Karr D. B., Strobel G. A. Isolation and Partial Characterization of Four Host-specific Toxins of Helminthosporium maydis (Race T). Plant Physiol. 1974 Feb;53(2):250–257. doi: 10.1104/pp.53.2.250. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Mertz S. M., Arntzen C. J. Selective Inhibition of K, Na, Cl, and PO(4) Uptake in Zea mays L. by Bipolaris (Helminthosporium) maydis Race T Pathotoxin: Evidence for a Plasmalemma Target Site? Plant Physiol. 1977 Sep;60(3):363–369. doi: 10.1104/pp.60.3.363. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Miller R. J., Koeppe D. E. Southern corn leaf blight: susceptible and resistant mitochondria. Science. 1971 Jul 2;173(3991):67–69. doi: 10.1126/science.173.3991.67. [DOI] [PubMed] [Google Scholar]
- Zeiger E., Hepler P. K. Production of guard cell protoplasts from onion and tobacco. Plant Physiol. 1976 Oct;58(4):492–498. doi: 10.1104/pp.58.4.492. [DOI] [PMC free article] [PubMed] [Google Scholar]