Search Results for: plants stress

Author: Lichtenthaler, H.K. Description: The current concept of stress in plants has been well developed over the past 60 years. Any unfavorable condition or substance that affects or blocks a plant’s metabolism, growth, or development is regarded as stress. Vegetation stress can be induced by various natural and anthropogenic stress factors. One has to differentiate between short-term and long-term stress effects as well as between low-stress events that can be partially compensated for by acclimation, adaptation, and repair mechanisms, on the one hand, and strong stress or chronic stress events…

Author: Callaway, R.M.; Brooker, R.W.; Choler, P.; Kikvidze, Z.; Lortie, C.J.; Michalet, R.; Paolini, L.; Pugnaire, F.I.; Newingham, B.; Aschehoug, E.T.; Armas, C.; Kikodze, D.; Cook, B.J. Description: Plants can have positive effects on each other. For example, the accumulation of nutrients, provision of shade, amelioration of disturbance, or protection from herbivores by some species can enhance the performance of neighbouring species. Thus the notion that the distributions and abundances of plant species are independent of other species may be inadequate as a theoretical underpinning for understanding species coexistence and…

Author: Kotak, S.; Larkindale, J.; Lee, U.; von Koskull-Doring, P.; Vierling, E.; Scharf, K.-D. Description: Plants have evolved a variety of responses to elevated temperatures that minimize damage and ensure protection of cellular homeostasis. New information about the structure and function of heat stress proteins and molecular chaperones has become available. At the same time, transcriptome analysis of Arabidopsis has revealed the involvement of factors other than classical heat stress responsive genes in thermotolerance. Recent reports suggest that both plant hormones and reactive oxygen species also contribute to heat stress…

Author: Neumann, D.; Lichtenberger, O.; Gnther, D.; Tschiersch, K.; Nover, L. Description: Cell cultures of Lycopersicon peruvianum L. stressed with CdSO4 (10−3M) show typical changes in the ultrastructure, starting with the plasmalemma and later on extending to the endoplasmic reticulum and the mitochondrial envelope. Part of the membrane material is extruded, with the formation of osmiophilic droplets which increase in size and number during the stress period. After 4 h, about 20‰ of the cells are dead. A short heat stress preceeding the heavy-metal stress induces a tolerance effect by…

Author: Root, T.L.; Price, J.T.; Hall, K.R.; Schneider, S.H.; Rosenzweig, C.; Pounds, J.A. Description: Over the past 100 years, the global average temperature has increased by approximately 0.6 degrees C and is projected to continue to rise at a rapid rate. Although species have responded to climatic changes throughout their evolutionary history, a primary concern for wild species and their ecosystems is this rapid rate of change. We gathered information on species and global warming from 143 studies for our meta-analyses. These analyses reveal a consistent temperature-related shift, or ‘fingerprint’,…

Author: Quint, Marcel; Delker, Carolin; Franklin, Keara A.; Wigge, Philip A.; Halliday, Karen J.; van Zanten, Martijn Description: Temperature is a major factor governing the distribution and seasonal behaviour of plants. Being sessile, plants are highly responsive to small differences in temperature and adjust their growth and development accordingly. The suite of morphological and architectural changes induced by high ambient temperatures, below the heat-stress range, is collectively called thermomorphogenesis. Understanding the molecular genetic circuitries underlying thermomorphogenesis is particularly relevant in the context of climate change, as this knowledge will be…

Author: Cazale, Anne-Claire; Clement, Mathilde; Chiarenza, Serge; Roncato, Marie-Anne; Pochon, Nathalie; Creff, Audrey; Marin, Elena; Leonhardt, Nathalie; Noel, Laurent D. Description: Molecular chaperones of the heat shock cognate 70 kDa (HSC70) family are highly conserved in all living organisms and assist nascent protein folding in normal physiological conditions as well as in biotic and abiotic stress conditions. In the absence of specific inhibitors or viable knockout mutants, cytosolic/nuclear HSC70-1 overexpression (OE) and mutants in the HSC70 co-chaperone SGT1 (suppressor of G(2)/M allele of skp1) were used as genetic tools to…

Author: Salvucci, Michael E. Description: Previous studies have shown that inhibition of photosynthesis by moderate heat stress is a consequence of Rubisco deactivation, caused in part by the thermal instability of Rubisco activase. This involvement of Rubisco activase was confirmed in heat stress and recovery experiments using transgenic Arabidopsis plants. Compared with wild-type plants, photosynthesis, the effective quantum yield of photosystem II, and Rubisco activation were less thermotolerant and recovered more slowly in transgenic Arabidopsis plants with reduced levels of Rubisco activase. Immunoblots showed that 65% of the Rubisco activase…

Author: Burgner, Samuel E.; Nemali, Krishna; Massa, Gioia D.; Wheeler, Raymond M.; Morrow, Robert C.; Mitchell, Cary A. Description: Among candidate leafy vegetable species initially considered for astronauts to pick and eat from the Veggie plant-growth unit on the International Space Station (ISS), Chinese cabbage (Brassica rapa L. cv. Tokyo Bekana) ranked high in ground-based screening studies. However, subsequent attempts to optimize growth within rigorous ISS-like growth environments on the ground were frustrated by development of leaf chlorosis, necrosis, and uneven growth. ‘Tokyo Bekana’ (‘TB’) grown on ISS during the…