Functional Plant Biology
Volume 40 Number 10 2013
FP13034Physiological perspectives of reduced tillering and stunting in the tiller inhibition (tin) mutant of wheat
Understanding tiller inhibition in the wheat tin mutant provides the opportunity to improve crop yield by manipulating tillering. The aim of this review was to demonstrate that both tiller inhibition and stunting in tin were associated with early internode development. Therefore, research on tillering should also focus on internode development and its regulation by environmental, developmental and genetic factors.
FP12294Early increased expression of a cyclin-dependant protein kinase (LtCDKA1;1) during inflorescence initiation of the long day grass Lolium temulentum
Understanding flowering is important for manipulating growth, seed production and yield of grasses and cereals. A feature of the floral transition is large increases in cell division at the shoot apex, but little is known about expression of cell cycle-related genes. In the grass Lolium temulentum, expression of one such regulatory gene, LtCDKA1;1, increases 6 h after the end of a florally inductive long day which precedes by 12–24 h that of an AP1 gene homologue involved in floral organ specification.
Fatty acid composition is critical for the quality of rice bran oil and storage of brown rice. Suppressing the expression of the OsFAD2–1 enzyme increases the content of oleic acid at the expense of linoleic and palmitic acid in rice grains. Oil from the transgenic rice is expected to be highly stable. The low linoleic acid content should improve the stability of rice oil and brown rice during storage.
FP13002The involvement of the mitochondrial peroxiredoxin PRXIIF in defining physiological differences between orthodox and recalcitrant seeds of two Acer species
Peroxiredoxines (PRXs) function as thiol-dependent peroxidases and modulate redox-dependent signalling during plant development and adaptation to environmental conditions. PRXIIF was investigated during progressive desiccation of orthodox and recalcitrant Acer seeds and decreased protein amounts, incomplete phosphorylation and alternation at the transcript level were detected in desiccation-sensitive seeds. Seed development, maturation, dormancy and germination are accompanied by production of reactive oxygen species, PRXs undergo phases of oxidation and participate in defining the physiological differences between contrary category seeds.
FP13010Estimation of the steady-state cyclic electron flux around PSI in spinach leaf discs in white light, CO2-enriched air and other varied conditions
In photosynthesis, electrons derived from water are driven uphill in a linear fashion as well as in a loop or cycle, both flows helping to convert CO2 into sugars. This study estimates the hitherto elusive rate of cyclic flow in leaves in CO2-enriched air. Estimates of cyclic flow will help to assess its role and elucidate its regulation in efficient photosynthesis.
FP12296Transcriptome analyses and virus induced gene silencing identify genes in the Rpp4-mediated Asian soybean rust resistance pathway
Asian soybean rust, caused by the fungus Phakopsora pachyrhizi, threatens soybean production worldwide. To examine how resistance occurs, we monitored the expression of ~37 000 soybean genes in response to P. pachyrhizi infection. Genes expressed across multiple resistant soybean lines will provide targets for developing novel sources of resistance to P. pachyrhizi and other harmful pathogens.
FP12377Overexpression of GsCBRLK from Glycine soja enhances tolerance to salt stress in transgenic alfalfa (Medicago sativa)
Much existing irrigated land is threatened by salinisation, so breeding high salt-tolerant plants is necessary to improve land use efficiency. In order to breed high salt-tolerant plants, transgenic alfalfa plants overexpressing GsCBRLK are generated, and the salt tolerance is significantly increased. Transgenic alfalfa grew well under high salinity conditions, so we hope transgenic alfalfa can be used to ameliorate salt-affected soils.
FP13060The source of nitrogen (NH4+ or NO3–) affects the concentration of oxalate in the shoots and the growth of Atriplex nummularia (oldman saltbush)
High concentrations of oxalate in leaves can lower the nutritive value of halophytic fodder plants. We studied the effects of nitrogen source on oxalate in a clone of oldman saltbush (Atriplex nummularia). After 24 days growth, plants supplied with ammonium instead of nitrate had 75% lower concentrations of oxalate in shoots, but also 57% less shoot dry mass.
The major challenge in plant phenotyping based on image analysis lies in the difficulty to discriminate relevant features from unimportant background information. We propose two approaches solving this problem, one applying methods from machine learning and a second one allowing user interaction. Although the approaches are presented for phenotyping of Arabidopsis thaliana, they can likewise be applied to feature extraction of digital images in other contexts.
FP12379External heat-pulse method allows comparative sapflow measurements in diverse functional types in a Mediterranean-type shrubland in South Africa
Divergent responses of coexisting species to short- and long-term climatic conditions may be significant in diverse floras, particularly those occurring in highly pulse-driven environments. Our aim was to test the efficacy of miniature external sapflow gauges for capturing physiological response of diverse coexisting functional types, including small monocotyledonous species. Our data show that the gauges approximate measures of transpiration well and that they will allow important fundamental ecophysiological questions to be investigated in future studies.