Plant physiology

About: Plant physiology is a research topic. Over the lifetime, 1537 publications have been published within this topic receiving 72038 citations.

The Growth of Maize (zea mays l.) under Field conditions as affected by its Water Relations.

Abstract: The growth potential of a plant is ultimately determined by its genetic make up. The environment, however, plays a major role. firing the extent to which the growth potential is expressed. Water, a major component of the environment, influences virtually all physiological processes, and constitutes one of the most important limiting factors in plant life . Much of the genetic expression for growth of a plant can be determined by the relative abundance of water in the growing medium.

The physiology of Salix

Abstract: Salix has many physiological features in common with other deciduous woody plants, e.g. C3 photosynthesis, occurrence of latitudinal photoperiodic ecotypes, and organic N (no ) flux to the shoot in the xylem. Special points about the physiology of Salix spp. which may have impact on their ecology and economic uses include: (i) relatively high (for woody plants) light-saturated rate of photosynthesis on a leaf area or leaf dry weight basis, (ii) sex differences in water (transpiration) costs of growth, (iii) very limited seed longevity and a wide range of temperature and light conditions permitting germination, and (iv) ready rooting and establishment of naturally or artificially detached twigs and branches. Areas in which work on Salix has been especially influential for the development of plant physiology include: (i) the analysis of phloem functioning using aphids, (ii) the role of photoinhibition under natural conditions, and (iii) the realisation that the woody habit need not constrain the achieved activity of enzymes and hence N-based metabolic rates.

Dark CO 2 fixation in leaves of tomato plants grown with ammonium and nitrate as nitrogen sources

Abstract: The dark (non-photosynthetic) CO2 fixation was studied in the leaves of ammonium-fed and nitratefed tomato plants. The ability to fix14CO2 in the dark of ammonium-fed plants was remarkably lower as compared with nitrate-fed plants, supporting the previous finding that the synthesis of C4-compounds from C3-compounds was reduced in the leaves of ammonium-fed plants. There was no difference in the activity of PEP carboxylase in extracts prepared from the leaves between both the plants during an early period of the treatment. However, the enzyme activity began to decrease rapidly in ammonium-fed plants 4 days after the treatment. By long-term treatments, the enzyme activity in ammonium-fed plants became half as high as that of nitrate-fed plants. The decreased PEP carboxylase activity in ammonium-fed plants was not associated with the presence of NH4-N and the absence of NO3-N in the leaf extract, and was not restored by the addition of the leaf extract from nitrate-fed plants. It is concluded that the decreased rate of synthesis of C4-compounds from C3-compounds in ammonium-fed plants is closely associated with a decrease in the dark fixation involving PEP carboxylase.

Impact of arbuscular mycorrhizal fungi (AMF) on gene expression of some cell wall and membrane elements of wheat (Triticum aestivum L.) under water deficit using transcriptome analysis

Abstract: Mycorrhizal symbiotic relationship is one of the most common collaborations between plant roots and the arbuscular mycorrhizal fungi (AMF). The first barrier for establishing this symbiosis is plant cell wall which strongly provides protection against biotic and abiotic stresses. The aim of this study was to investigate the gene expression changes in cell wall of wheat root cv. Chamran after inoculation with AMF, Funneliformis mosseae under two different irrigation regimes. To carry out this investigation, total RNA was extracted from the roots of mycorrhizal and non-mycorrhizal plants, and analyzed using RNA-Seq in an Illumina Next-Seq 500 platform. The results showed that symbiotic association between wheat and AMF and irrigation not only affect transcription profile of the plant growth, but also cell wall and membrane components. Of the 114428 genes expressed in wheat roots, the most differentially expressed genes were related to symbiotic plants under water stress. The most differentially expressed genes were observed in carbohydrate metabolic process, lipid metabolic process, cellulose synthase activity, membrane transports, nitrogen compound metabolic process and chitinase activity related genes. Our results indicated alteration in cell wall and membrane composition due to mycorrhization and irrigation regimes might have a noteworthy effect on the plant tolerance to water deficit.

Molecular cloning and characterization of a brassinosteriod biosynthesis-related gene PtoDWF4 from Populus tomentosa.

Abstract: Brassinosteroids (BRs) as steroid hormones play an important role in plant growth and development. However, little is known about how BRs affect secondary wall biosynthesis in woody plants. In this study, we cloned and characterized PtoDWF4, a homologus gene of Arabidopsis DWF4 encoding a cytochrome P450 protein, from Populus tomentosa. qRT-PCR analysis showed that PtoDWF4 was highly expressed in stems, especially in xylem. Overexpression of PtoDWF4 (PtoDWF4-OE) in poplar promoted growth rate and biomass yield, increased area and cell layers of xylem. Transgenic plants showed a significant increase in plant height and stem diameter compared with the wild type. In contrast, the CRISPR/Cas9-generated mutation of PtoDWF4 (PtoDWF4-KO) resulted in significantly decreased biomass production in transgenic plants. Further studies revealed that constitutive expression of PtoDWF4 up-regulated the expression of secondary cell wall (SCW) biosynthesis-related genes, whereas knock-out of PtoDWF4 down-regulated their expression. Quantitative analysis of cell wall components showed a significant increase in PtoDWF4-OE lines but a reduction in PtoDWF4-KO lines compared with wild-type plants. Taken together, our results indicate that PtoDWF4 plays a positive role in improving growth rate and elevating biomass production in poplar.