Objective. To determine the epidemiology of Haemophilus influenzae type b (Hib) and Streptococcus pneumoniae invasive infections in hospitalized Guatemalan children. This is an important issue since Hib vaccine has not been incorporated into the routine immunization program in Guatemala and information from hospital records in 1995 indicated

A chemical identification procedure previously used to identify apple clones was tried with pear species and clones. Following electrophoresis, the peroxidase, esterase, and acid phosphatase isozyme patterns on anionic polyacrylamide gradient gels were determined. These patterns were found to vary with the species and clone, but not to change, within a clone during the growing season. Thus, these patterns were considered to represent genetic characteristics. The patterns were used to identify 37 selected Pyrus accessions at the National Clonal Germplasm Repository, Corvallis, Oregon. All species tested were distinguishable using this system. All the accessions of P. calleryana selected from the NCGR collection were distinct: however, one clone from outside the collection had an identical pattern to one inside the collection. Among the Chinese pear clones (complex hybrids of P. ussuriensis × P. pyrifolia) tested, three pairs of clones had the same combination. This technique appears to have the potential to readily identify pear specimens, and could be an important aid in the characterization of germplasm material.

A chemical identification procedure previously used to identify apple and pear species, cultivars and clonal accessions, was tried with Corylus (filbert, hazel) species, cultivars and clonal accessions. Following electrophoresis, the peroxidase, phenol oxidase, and acid phosphatase isozyme patterns on anionic polyacrylamide gradient gels were determined. These patterns were found to vary between clonal accessions, but did not change, within a given accession during and following the test period (May through October). Thus, these patterns were considered to represent genetic characteristics suitable for identification purposes. The patterns were used to identify 78 Corylus accessions at the National Clonal Germplasm Repository Corvallis, Oregon. All accessions tested (species, cultivars and clones) were distinguishable using this system. The diversity of isozyme patterns was greater in Corylus than Pyrus populations previously sampled. This technique appears to have the potential to readily identify filbert accessions and could be an important aid in the characterization of germplasm material.

Polyacrylamide electrophoresis and spectroscopic methods were used to characterize biotypes A and B itchgrass [Rottboellia exaltataL.f. # ROOEX] and their F2progeny. Electrophoretic analyses of F2progeny showed that differences between these two biotypes are multiallelic. Spectrophotometric data indicated differences between the photosynthetic apparatus of the two biotypes. These differences may reflect different abilities to adapt to varying light conditions and infer that these biotypes promote survival of the species by increasing the number of environmental nitches thatR. exaltatacan occupy.