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The only species of the legume genus Vavilovia, a paleoendemic to the Caucasus commonly known simply as Vavilovia (V. formosa) has an extraordinary significance for the evolution and phylogeny of the tribe Fabeae, with its economically important species, such as lentil (Lens spp.) or pea (Pisum spp). This paper is attempting to deduce the genetic background of the materially perished, but thoroughly described, F1 progeny between Vavilovia and field pea (P. sativum var. arvense) in both crossing combinations, obtained by the N. I. Vavilov All-Russian Institute of Plant Genetic Resources (VIR), in 1988. Although with only one plant in each direction, the resulting phenotypes are the only known successful intergeneric hybridisation in legumes with impressively interesting features, such as the trifoliolate leaves absent in both parents, as well as vastly inspiring and potentially useful for the conservation of Vavilovia and crop improvement of pea and other species of the tribe.

Rare wild hybrids occur between five of the six genera in the New Zealand endemicRaouliaalliance. Some of these intergeneric hybrids are partially male and female fertile despite the remarkable phenotypic divergence of the parental species. In this preliminary study, meiotic behaviour was investigated in microsporocytes of two wild hybrids,Anaphalioides bellidioides×Ewartiothamnus sinclairiiandLeucogenes grandiceps×Raoulia eximia, to obtain insights into the cytological phenomena responsible for the reduced pollen fertility of the hybrids. In theA. bellidioides×E. sinclairiihybrid, up to five chromosomal bodies were non-aligned along the metaphase plate in metaphase I, and laggard chromosomes and chromosomal bridges were observed in anaphase I. Micronuclei were observed in telophases I and II in 20% and 24% of microsporocytes, respectively. These abnormalities were observed at a low frequency in theL. grandiceps×R. eximiahybrid, which showed more highly regular meiosis. The difference in meiotic regularity shown by the two hybrids is in stark contrast to the comparative phenotypic divergence of the parental species. [ABSTRACT FROM AUTHOR]

Four intergeneric hybrids were produced by crossing sorghum [ Sorghum bicolor (L.) Moench, 2n =20] as a female parent with sugarcane ( Saccharum officinarum L., 2n = 112). The hybrids were morphologically similar to the sugarcane parent, but lacked vegetative vigour. Sorghum characters present in the hybrids included soft texture of the leaves, tight clasping of the leaf sheaths, presence of aerial roots and triangular ligule. All the hybrids were highly susceptible to natural incidence of mites. Somatic chromosome number of the hybrids ranged from 2n = 62–66, indicating n+n transmission. This is the first report of Sorghum × Saccharum hybrids with sorghum cytoplasm. [ABSTRACT FROM AUTHOR]

Studies were conducted to investigate the crossability of the cultivated Brassica species, Brassica napus (oilseed rape), B. rapa (turnip rape), and B. juncea (brown and oriental mustard), with two related cruciferous weeds that are abundant in certain regions of Canada, Erucastrum gallicum (dog mustard) and Raphanus raphanistrum ssp. raphanistrum (wild radish). Seed was produced without recourse to embryo rescue from all reciprocal crosses except R. raphanistrum × B. juncea. Four hybrid plants were recovered, namely B. napus × E. gallicum, B. napus × R. raphanistrum (two plants), and B. rapa × E. gallicum. The hybrids were characterized by their morphology, RAPD analysis, and cytological examination. The B. rapa × E. gallicum hybrid was extremely vigourous and fertile, and would likely grow in natural habitats. This hybrid produced self-seed and backcrossed readily with the B. rapa parent and, to a lesser extent, with the E. gallicum parent. The B. napus × E. gallicum hybrid was a weak plant, but produced fertile backcross progeny with the E. gallicum parent. The B. napus × R. raphanistrum hybrids were vigourous but mostly sterile. Because of their low vigour and/or sterility, hybrids produced from crosses of B. napus with the cruciferous weeds would not likely be an environmental concern. However, the potential of the B. napus × E. gallicum and B. rapa × E. gallicum hybrids to backcross with E. gallicum may be of concern. [ABSTRACT FROM AUTHOR]