Flooding is a phenomenon that destroys many crops worldwide. During evolution several plant species evolved specialized mechanisms to survive short- or long-term waterlogging and even complete submergence. One of the plant species that evolved such a mechanism is Rumex palustris. When flooded, this plant species is capable to elongate its petioles to reach the surface of the water. Thereby it r...

' Received Sept. 27, 1962. ing 125 mm being miiade up with either argon or ethylene. The followiing gas mixtures were used: air, 10 % 02 + 90% A, 7.5% O., + 92.5 % A, 5% 02 + 95% A. In other experimlenits the partial pressure of ethylene in the jars was varied from 0 to 253 nim Hg, while the O. level was maintained at 5 % and total pressure adjusted to 760 mim with argon. For comparative purpos...

A Russian knapweed (Acroptilon repens) shoot culture system, initiated from shoot tip culture, was used to generate a source of host plant tissue for the rearing of the nematode Subanguina picridis, a biocontrol agent for Russian knapweed. Young shoots growing on solid B5G medium in petri dishes developed galls on leaves, petioles, and shoot tips 7 days after release of 50 nematodes onto the su...

Studies on the development dynamics and the physiological properties of heterotrophic bacteria growing on the surface of the yellow waterlily {Nuphar luteum L.) during the plants' development cycle were carried out. It was stated that the number of the epiphytic bacteria is different in the examined sections of the plant. The number is higher on bottom parts of petioles and rhizomes but lower o...

At the end of a 4 hour absorption period approximately 95% of the sodium absorbed by bean plants was retained in the secondary roots. The sodium translocated to the shoot was retained in the stem.2,4-Dinitrophenol decreased the amount retained in the secondary roots of bean plants and increased the amount translocated to the shoot. The stem retained most of the translocated sodium.Bean plants w...

Upward physical restraint of the normally horizontal bracts of poinsettia (Euphorbia pulcherrima Willd.) resulted in increased ethylene production and epinastic curvature of the petioles after 5 days. Downward restraint caused little change in ethylene production or epinasty, indicating that the enhanced ethylene production observed in petioles bent upwards is not due to the bending stress alon...

We have identified three Arabidopsis genes with GAMYB-like activity, AtMYB33, AtMYB65, and AtMYB101, which can substitute for barley (Hordeum vulgare) GAMYB in transactivating the barley alpha-amylase promoter. We have investigated the relationships between gibberellins (GAs), these GAMYB-like genes, and petiole elongation and flowering of Arabidopsis. Within 1 to 2 d of transferring plants fro...