Yehoshua Anikster received B.S. and M.S. degrees from Hebrew University of Jerusalem and a Ph.D. degree from Tel Aviv University in Israel. He served as director of the Institute for Cereal Crops Improvement and on the faculty at Tel Aviv University, where he currently is a professor emeritus. Anikster’s career has largely been devoted to the study of rust fungi that attack Old World cultivated cereals: wheat, barley, oats, and their wild relatives. He was fortunate in that his research could be performed in an area where the pathogens and their main and alternate hosts are native and have coevolved. In addition to evolutionary studies, Anikster has led projects for the conservation of wild plants as genetic resources for breeding.
Anikster developed tools for analyzing the evolutionary biology of rust diseases. He also developed techniques for teliospore germination under controlled conditions, enabling their use to inoculate suitable alternate hosts of the studied fungi. Cytological studies carried out in parallel with inoculation experiments provided a complete picture of the nuclear history of a specific life cycle. For example, his analyses of members of the genus Uromyces parasitizing Hordeum hosts resulted in the discovery and naming of the three new macrocyclic rust species U. viennot bourginii, U. reichertii, and U. christensenii, as well as a description of their life cycles on their respective hosts. On the alternate liliaceous host species, Anikster discovered and named related microcyclic taxa. Based on these findings, evolutionary connections were established between the macrocyclic fungal types and their microcyclic relatives, including some intermediate forms that are only rarely found in studies of evolutionary pathways.
An analysis of nuclear history during teliospore germination in more than 30 species of the genera Puccinia and Uromyces demonstrated that, as a general rule, meiosis in the basidium is followed by a mitotic division. The resulting eight nuclei may either migrate into four binucleate basidiospores, as in most macrocyclic rusts, or form only two tetranucleate basidiospores. This latter type is dominant in the microcyclic rusts and in a few of the macrocyclic species, in which aecial clusters are formed directly without pycnia. Twenty years after this discovery, during the late 1990s, he found tetranucleate basidiospores of the autoecious rust, P. allii, infecting garlic and chives in California and Oregon.
In cooperation with others, Anikster also studied molecular aspects of the rust-host interaction. Two types (equivalent to the + and – mating types of pycniospores) of a 120-kD protein were detected in the pycnial nectar of 11 rust species. These proteins are responsible for the formation of the proteinaceous polar caps (also found by Anikster and associates) on the pycniospores of the respective opposite mating type, a presumed prerequisite for fertilization. They are mating-type specific but not species specific; interspecific transfer of the same pycnial nectar among 11 taxa induced pycniospore caps on the respective opposite mating type.
More than a decade of work was dedicated to identifying the complex of leaf rust taxa that attack wheat, rye, and their close relatives in the genus Aegilops. The components of this complex were identified by several methods, including measures of DNA amounts in pycniospore nuclei. Identification of the specific alternate host also was carried out under controlled conditions. Cross compatibility between different fungal isolates was tested by manipulation during the sexual stage. The urediniospore substomatal vesicle shape was studied microscopically. An image-analysis technique was specially adapted to measure areas of urediniospores, teliospores, and basidiospores. Another analytical tool involved the use of ITS sequence data in collaboration with Les L. Szabo at the University of Minnesota. The combined use of these methods provided a very powerful and accurate tool for the identification of rust taxa. Anikster’s work forms the basis for identification of the world’s wheat leaf rust as Puccinia triticina. Subsequently, Anikster found an additional form of P. triticina on A. speltiodes in Israel. The leaf rusts that attack cultivated durum wheat in Morocco and Spain, as well as various Aegilops spp. all over the Mediterranean Basin, were identified as forms of P. recondita, which also attacks cultivated and wild rye all over the world.
Anikster is heavily involved in conservation of wild-growing relatives of crop plants as resources for future breeding for disease resistance. Since 1970, Anikster has taken charge of the systematic seed collection of progenitors and wild relatives of cultivated wheat, barley, and oats at the Institute for Cereal Crops Improvement (ICCI). The natural habitats of these species are increasingly being destroyed by urbanization. The seed bank of the ICCI now represents one of the world’s largest collections of wild relatives of these grain crops, with 10,000 accessions of wild wheats (including the wild emmer wheat and Aegilops spp.); more than 7,000 accessions of wild barley, mostly of Hordeum spontaneum; the progenitor of cultivated barley; and 2,000 accessions of wild oats, mostly of the hexaploid Avena sterilis, which is crossable with cultivated oats. The contents of the seed bank have been subjected to assessments for resistance to rusts and powdery mildews.
Anikster has contributed to the overall scientific community in many ways. He headed the ICCI during 1986–1991 and 1999–2000. For about 10 years (1983–1992), Anikster coordinated the All Israeli Universities “Ammiad Project”, which was a pilot study for in situ conservation of wild emmer, the wild tetraploid Triticum turgidum var. dicoccoides. The findings led to recommendations on locations and management of conservation sites and on ways to manipulate natural variation. From 1991 to 1996, he was a member of the Scientific Advisory Committee of an in situ Genetic Diversity World Bank project in Turkey. During 1999, Anikster coordinated an Israeli-Palestinian project to rescue a collection of crop plant relatives with economic potential that were being increasingly endangered by the destruction of their habitats. Anikster has been heavily involved in teaching plant pathology and related topics and in supervising graduate students. He has cooperated with many scientists in Israel, the United States, and other countries.
In view of his many achievements, Anikster is highly deserving of the APS Fellow Award.
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