Pathogenicity of Hirschmanniella oryzae,H. spinicaudata,and H. imamuri on Rice

In greenhouse experiments Hirschmanniella oryzae, H. imamuri, and H. spinicaudata depressed and delayed the tillering and flowering of rice, and suppressed root and shoot growth and grain yield.     

HYBRIDS AND GENOME RELATIONS OF HIBISCUS SABDARIFFA,H. MEEUSEI,H. RADIATUS AND H. ACETOSELLA

Chromosome pairing was studied in the following hybrids: Hibiscus radiatus-meeusei (tetraploid F₁), H. sabdariffa-meeusei (tetraploid F₁ and spontaneous allooctoploid F₂), and hexaploid H. acetosella-(sabdariffa-meeusei). Genome constitutions of the species adduced from these data are symbolized as follows: H. radiatus and H. acetosella, AABB; H. meeusei, AAXX; H.sabdariffa, XXYY or AAYY.     

Phylogenetic analysis of the core histones H2A, H2B, H3, and H4.

Despite the ubiquity of histones in eukaryotes and their important role in determining the structure and function of chromatin, no detailed studies of the evolution of the histones have been reported. We have constructed phylogenetic trees for the core histones H2A, H2B, H3, and H4. Histones which form dimers (H2A/H2B and H3/H4) have very similar trees and appear to have co-evolved, with the exception of the divergent sea urchin testis H2Bs, for which no corresponding divergent H2As have been identified. The trees for H2A and H2B also support the theory that animals and fungi have a common ancestor. H3 and H4 are 10-fold less divergent than H2A and H2B. Three evolutionary histories are observed for histone variants. H2A.F/Z-type variants arose once early in evolution, while H2A.X variants arose separately, during the evolution of multicellular animals. H3.3-type variants have arisen in multiple independent events.     

Comparisons of the hybrids Hordeum chilensexH. vulgare,H. chilensexH. bulbosum,H. chilensexSecale cereale and the amphidiploid of H. chilensexH. vulgare

Summary Diploid hybrids between Hordeum chilense and three other species, namely H. vulgare, H. bulbosum and Secale cereale, are described together with the amphidiploid of H. chilensexH. vulgare. Both the diploid hybrid and the amphidiploid of H. chilensexH. vulgare were chromosomally unstable, H. chilensexH. bulbosum was less so, while H. chilensexS. cereale was stable. Differential amphiplasty was found in all combinations. No homoeologous pairing was found in the Hordeum hybrids but in H. chilensexS. cereale there was chromosome pairing both within the two genomes and between the genomes.