Singlet oxygen (O) has a very short half-life of 10 s; however, it is a strong oxidant that causes growth arrest and necrotic lesions on plants. Its signaling pathway remains largely unknown. The Arabidopsis flu (fluorescent) mutant accumulates a high level of O and shows drastic changes in nuclear gene expression.
View Article and Find Full Text PDFAfter nitrogen treatments, plant leaves become narrower and thicker, and the chlorophyll content increases. However, the molecular mechanisms behind these regulations remain unknown. Here, we found that the changes in leaf width and thickness were largely compromised in the () mutant.
View Article and Find Full Text PDFOilseed rape () is a Cadmium (Cd) hyperaccumulator. However, high-level Cd at the early seedling stage seriously arrests the growth of rape, which limits its applications. had higher Cd accumulation capacity, but its biomass was lower, also limiting its applications.
View Article and Find Full Text PDFIn China, maize-soybean relay-intercropping system follow the two main planting-patterns: (i) traditional relay-intercropping; maize-soybean equal row planting, where soybean experience severe maize shading on both sides of plants, and (ii) modern relay-intercropping; narrow-wide row planting, in this new planting pattern only one side of soybean leaves suffer from maize shading. Therefore, in this study, changes in morphological traits, cytochrome content, photosynthetic characteristics, carbon status, and the activities of superoxide dismutase (SOD), peroxidase (POD), catalase (CAT) and ascorbate peroxidase (APX) were investigated at 30 days after treatment (DAT) in shade-tolerant soybean variety Nandou-12 subjected to three different types of shading conditions; normal light (NL, all trifoliate-leaves of soybean plants were under normal light); unilateral shade (US, all right-side trifoliate-leaves of soybean plants from top to bottom were under shade while all the left-side of trifoliate-leaves from top to bottom were in normal light); bilateral shade (BS, all trifoliate-leaves of soybean plants were under complete shade). Compared with BS, US conditions decreased plant height and increased stem diameter, leaf area, and biomass at 30 DAT.
View Article and Find Full Text PDFCalcium-dependent protein kinase (CPKs) is a key player in the calcium signaling pathway to decode calcium signals into various physiological responses. cDNA sequences of 9 CPK genes were successfully cloned from all four phylogenetic groups in maize. qRT-PCR analysis showed the expression variation of these selected genes under abscisic acid (ABA) and calcium chloride (CaCl) treatment.
View Article and Find Full Text PDFShading conditions adversely affect flower-number and pod-number of soybeans under maize-soybean relay-intercropping (MS). Here we reveal that leaf-removal from maize-canopy improves the photosynthetically active radiation (PAR) transmittance and dry-matter production (DMP) of soybean (especially during the co-growth phase), and compensates the maize seed-yield loss by considerably increasing soybean seed-yield. In a two-year experiment with MS, maize-plants were subjected to different leaf-removal treatments to increase the PAR-transmittance of soybean; removal of the topmost two-leaves (R2), four-leaves (R4), six-leaves (R6), with no-removal of leaves (R0).
View Article and Find Full Text PDFBackground: Maize-soybean relay-intercropping (MS) is a famous system of crop production in developing countries. However, maize shading under this system directly affects the light quality and intensity of soybean canopy. This is a challenging scenario in which to implement the MS system, in terms of varieties selection, planting pattern, and crop management since the duration of crop resource utilization clearly differs.
View Article and Find Full Text PDFThe 5-leaf-stage rape seedlings were more insensitive to Pi starvation than that of the 3-leaf-stage plants, which may be attributed to the higher expression levels of ethylene signaling and sugar-metabolism genes in more mature seedlings. Traditional suppression subtractive hybridization (SSH) and RNA-Seq usually screen out thousands of differentially expressed genes. However, identification of the most important regulators has not been performed to date.
View Article and Find Full Text PDFPlanting patterns affect nitrogen (N), phosphorus (P), and potassium (K) acquisition and distribution in maize and soybean under intercropping conditions. Here we reveal that strip relay-intercropping increases the N, P, and K uptake and distribution across plant organs (root, straw, and seed) of maize and soybean, accelerates the dry-matter production of intercrop-species, and compensates the slight maize yield loss by considerably increasing the soybean yield. In a two-year experiment, soybean was planted with maize in different planting patterns (SI, 50:50 cm and SII, 40:160 cm) of relay-intercropping, both planting patterns were compared with sole cropping of maize (SM) and soybean (SS).
View Article and Find Full Text PDFNitric oxide (NO) has a general inhibitory effects on chlorophyll biosynthesis, especially to the step of 5-aminolevulinic acid (ALA) biosynthesis and protochlorophyllide (Pchlide) to chlorophyllide (Chlide) conversion (responsible by the NADPH:Pchlide oxidoreductase POR). Previous study suggested that barley large POR aggregates may be generated by dithiol oxidation of cysteines of two POR monomers, which can be disconnected by some reducing agents. POR aggregate assembly may be correlated with seedling greening in barley, but not in Arabidopsis.
View Article and Find Full Text PDFPlant Cell Environ
September 2017
Nitric oxide (NO) is extensively involved in various growth processes and stress responses in plants; however, the regulatory mechanism of NO-modulated cellular sugar metabolism is still largely unknown. Here, we report that NO significantly inhibited monosaccharide catabolism by modulating sugar metabolic enzymes through S-nitrosylation (mainly by oxidizing dihydrolipoamide, a cofactor of pyruvate dehydrogenase). These S-nitrosylation modifications led to a decrease in cellular glycolysis enzymes and ATP synthase activities as well as declines in the content of acetyl coenzyme A, ATP, ADP-glucose and UDP-glucose, which eventually caused polysaccharide-biosynthesis inhibition and monosaccharide accumulation.
View Article and Find Full Text PDFThe relationship between Mg-protoporphyrin IX (Mg-Proto IX) signals and plant's tolerance to cold stress is investigated. seedlings grown for 3 weeks were pretreated with 2 mM glutamate (Glu) and 2 mM MgCl for 48 h at room temperature to induce Mg-Proto IX accumulation. Then cold stress was performed at 4°C for additional 72 h.
View Article and Find Full Text PDFProc Natl Acad Sci U S A
July 2016
The phenomenon of delayed flowering after the application of nitrogen (N) fertilizer has long been known in agriculture, but the detailed molecular basis for this phenomenon is largely unclear. Here we used a modified method of suppression-subtractive hybridization to identify two key factors involved in N-regulated flowering time control in Arabidopsis thaliana, namely ferredoxin-NADP(+)-oxidoreductase and the blue-light receptor cryptochrome 1 (CRY1). The expression of both genes is induced by low N levels, and their loss-of-function mutants are insensitive to altered N concentration.
View Article and Find Full Text PDFGenetic and physiological studies have revealed evidences for multiple signaling pathways by which the plastid exerts retrograde control over photosynthesis-associated-nuclear-genes. In this study we have examined the mechanisms of control of transcription by plastid signals, focusing on transcription factors. We have also further addressed the physical nature of plastid signals and the physiological role, in stress acclimation of this regulatory pathway.
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