The Columbia root-knot nematode, Meloidogyne chitwoodi race 2, is associated with several plant species, including members of the tribe Triticeae. We evaluated 15 diploid species for M. chitwoodi gall and reproductive indices from the following genera: Agropyron, Pseudoroegneria, Hordeum, Psathyrostachys, and Thinopyrum. Species from the genus Thinopyrum (Thinopyrum bessarabicum; J genome) and ...

Agropyron Gaertn. (P genome) is a wild relative of wheat that harbours many genetic variations that could be used to increase the genetic diversity of wheat. To agronomically transfer important genes from the P genome to a wheat chromosome by induced homoeologous pairing and recombination, it is necessary to determine the chromosomal relationships between Agropyron and wheat. Here, we report us...

New speckle holographic images of the T Tauri infrared companion (T Tauri IRC; T Tauri S) reveal it to be a double system with a sky-projected separation of 0&farcs;05, corresponding to a linear distance of 7 AU. The presence of this third star may account for the relative paucity of dust surrounding the IRC.

We use near-infrared photometry of objects detected by IRAS to confirm four new T Tauri stars in Chamaeleon II. Observations of these sources generally agree with the T Tauri signatures of locus in the near-infrared color-color diagram, midinfrared spectral index, and IRAS far-infrared colors. Infrared properties of these stars are similar to optically selected T Tauri stars in Cha II, but are ...

Bunchgrasses are one of the most important plant functional groups in grassland ecosystems. Reproductive allocation (RA) for a bunchgrass is a hierarchical process; however, how bunchgrasses adjust their RAs along hierarchical levels in response to nutrient addition has never been addressed. Here, utilizing an 11-year nutrient addition experiment, we examined the patterns and variations in RA o...