On February 21, 2022 Prof. Dr. Klaus Raschke, Emeritus of the Georg-August-University of Göttingen in Göttingen passed away. The German Botanical Society remembers Klaus Raschke as a pioneering plant physiologist. His main research interest was the question of how CO2 uptake and H2O release through the stomata of the leaves are adapted to environmental conditions. He succeeded in identifying the biochemical-biophysical processes underlying the opening and closing of the stomata and in characterizing important regulatory parameters. The work of Klaus Raschke and his colleagues made an important contribution to the development of climate models.
Upon discovery that the Boquila trifoliolata is capable of flexible leaf mimicry, the question of the mechanism behind this ability has been unanswered. Here, we demonstrate that plant vision possibly via plant-specific ocelli is a plausible hypothesis. A simple experiment by placing an artificial vine model above the living plants has shown that these will attempt to mimic the artificial leaves. The experiment has been carried out with multiple plants, and each plant has shown attempts at mimicry. It was observed that mimic leaves showed altered leaf areas, perimeters, lengths, and widths compared to non-mimic leaves. We have calculated four morphometrical features and observed that mimic leaves showed higher aspect ratio and lower rectangularity and form factor compared to non-mimic leaves.
Broadening the definition of a nervous system to better understand the evolution of plants and animals
Sergio Miguel-Tomé & Rodolfo R. Llinás
Most textbook definitions recognize only animals as having nervous systems. However, for the past couple decades, botanists have been meticulously studying long-distance signaling systems in plants, and some researchers have stated that plants have a simple nervous system. Thus, an academic conflict has emerged between those who defend and those who deny the existence of a nervous system in plants. This article analyses that debate, and we propose an alternative to answering yes or no: broadening the definition of a nervous system to include plants. We claim that a definition broader than the current one, which is based only on a phylogenetic viewpoint, would be helpful in obtaining a deeper understanding of how evolution has driven the features of signal generation, transmission and processing in multicellular beings.
Autophagy is important for resetting memory of heat stress via control of heat shock proteins degradation. Autophagy mutants retain heat shock proteins longer and, therefore, display longer thermomemory.
Stamen presentation in Nasa poissoniana (Loasaceae) flowers is based on previously experienced pollinator visitation intervals. Using the unique ability of fast and precise stamen movements in response to a previous experiences with pollinators. Flowers of Nasa poissoniana are able to perceive, record and memorize visitations and adjust their flower behavior based on previous experiences. In other words, flowers anticipate revisits of pollinators by learning from previously experienced visitation intervals.
Maize plants can detect the presence of their neighbours and modify
their growth behaviour. Above ground interactions between neighboring
maize plants by brief light touches affect on below-ground root-root
communication. This study urges re-interpretation of results in
experiments in which plants are touched during the experiment. The
ecological significance of the observed responses still needs to be
Arabidopsis trichomes (hair cells) respond to mechanical stimuli by initiating potential signaling factors in themselves and in the neighboring cells. These vibrational responses of Arabidopsis trichomes support the hypothesis that trichomes respond acoustically to vibrations associated with feeding caterpillars. Trichomes have vibrational modes in the frequency range of the sounds of feeding caterpillars, encouraging further experimentation to determine whether trichomes serve as mechanical antennae. Arabidopsis plants have been reported recently to react to the sounds of caterpillars of Pieris rapae chewing on its leaves by promoting synthesis of toxins that can deter herbivory. Identifying leaf trichomes as acoustic antennae of plant cells suggests potential “ears” of Arabidopsis.