In Rhododendron spp. and Ledum groenlandicum a callose wall is laid down around the zygote in the first 2 days after fertilization. The periodic acid/Schiff-positive, aniline blue-fluorescence-positive callosic wall is initiated adjacent to the degenerating synergid, extends to cover the entire zygote surface, and remains visible during the initiation of embryogeny as the zygote elongates befor...

The azalea lace bug, Stephanitis pyrioides (Scott) (Tingidae: Hempitera), is a major pest of azaleas (Rhododendron L. spp.). Since its introduction from Asia in the 1940s, the pest has spread considerably within and outside the US. It causes severe economic damage to azaleas and also attacks other ericaceous hosts. The widespread acceptance and cultivation of its preferred host plants, azaleas,...

Rhododendron is one of the largest shrubs and is well known as a garden plant because of their evergreen leaves and various flower colors. The present study investigated the variation in amino acids in the differently colored flowers of Rhododendron schlippenbachii. Analysis of the Rhododendron flowers revealed 22 types of amino acids. The amino acid content varied greatly depending on the diff...

BACKGROUND Plants are traditionally used for medicinal treatment of numerous human disorders including infectious diseases caused by microorganisms. Due to the increasing resistance of many pathogens to commonly used antimicrobial agents, there is an urgent need for novel antimicrobial compounds. Plants of the genus Rhododendron belong to the woody representatives of the family Ericaceae, which...

Shoot extension of Rhododendron ‘Sir Robert Peel’ was reduced, but flowering was more precocious after treatment of plants with paclobutrazol. All of the drench rates tested (0.05 to 0.4 g a.i./pot) proved excessive and resulted in prolonged shoot growth reduction but greatly increased the number of flowers. However, flowers produced at the higher drench rates were grossly malformed and unaccep...

Small canopy openings often alter understory microclimate, leading to changes in forest structure and composition. It is generally accepted that physical changes in the understory (i.e., microclimatic) due to canopy removal drive changes in basic forest processes, particularly seedling recruitment which is intrinsically linked to soil moisture availability, light and, to a lesser extent, temper...