Acta Physiologiae Plantarum最新文献

In this experiment, itaconic acid, maleic acid, acrylic acid and potassium persulphate were polymerized to form synergist, which was wrapped on the surface of phosphate fertilizer particles to make synergistic phosphate fertilizer. In order to explore the effects of synergistic phosphate fertilizer on photosynthetic characteristics and senescence of wheat flag leaf in saline-alkali land, experiments were carried out in Changyi Experimental Base of Qingdao Agricultural University from October 2019 to June 2020 and from October 2020 to June 2021. Four treatments were set in the experiment, CK: nitrogen fertilizer (containing N 306.14 kg / hm²), potassium fertilizer (containing K₂O 116.67 kg / hm²), conventional phosphate fertilizer (containing P₂O₅ 333.35 kg / hm²); T1: synergic phosphate fertilizer (containing P₂O₅ 249.99 kg / hm²); T2: synergic phosphate fertilizer (containing P₂O₅ 166.67 kg / hm²); T3: synergic phosphate fertilizer (containing P₂O₅ 83.32 kg / hm²). The application amount of nitrogen and potassium fertilizer in T1, T2 and T3 was the same as that in CK. Photosynthetic characteristics and senescence indexes of wheat at 0–28 days after anthesis were measured. The results showed that the photosynthetic characteristics and the senescence of wheat treated with synergistic phosphate fertilizer were better than CK, and T2 treatment was the best.

Iron (Fe) deficiency chlorosis (FDC) in plant is associated with high bicarbonate concentration in calcareous soil and irrigation water, which leads to new leaf yellowing and lessens crop yield and quality. However, little is known about whether the chlorosis under bicarbonate stress resulted from blocking root–shoot Fe translocation or root Fe absorption. Moreover, the molecular response of chlorotic leaf under bicarbonate stress has been rarely reported on. The purpose of this study was to investigate the effect of bicarbonate on Fe acquisition, Fe translocation as well as Fe accumulation in roots, normal leaf (NL) and chlorotic leaf (CL) of Medicago lupulina. Seeds were grown with and without Fe and NaHCO₃ (Fe and Bic) in the nutrient solution for 10 d. Fe content, gene expression and enzymatic activity in different tissues were determined. A factorial statistical design with two factors (Fe and Bic) and two levels of each factor was adopted: + Fe, −Fe, + Fe + Bic and −Fe + Bic. Results indicated that bicarbonate stress increased the expression of genes MlHA1, MlFRO1 and MlIRT1 related to Fe acquisition and promoted the Fe absorption from solution. Furthermore, the presence of bicarbonate stress inhibited the expression of MlMATE66 in roots, prevented the Fe translocation from roots to developing leaf, brought about Fe accumulation in roots and reduced the Fe content in new leaf. Generally, according to our results, bicarbonate could prevent Fe translocation from roots into developing leaf, decrease Fe bioavailability and induce chlorosis in M. lupulina.

The association of bean yellow mosaic potyvirus (BYMV) was investigated earlier with the severe mosaic and stunting disease of V. faba. In the present study, we mechanically transmitted BYMV on V. faba to assess the impact on physiological, biochemical, and nutritional attributes. BYMV-inoculated plants exhibited severe symptoms, and their height, length of the pod, and seed yield (size and number) were reduced to half of the mock-inoculated V. faba. In BYMV-inoculated V. faba, chlorophyll a, b, and total (Chl a + Chl b) were lowered to 66.70%, 64.94%, and 66.19% respectively, and corroborated with the decrease in photosynthetic efficiency (Fv/Fm) from 0.36 to 0.26. An increase in membrane ion leakage and malondialdehyde was observed in inoculated V. faba indicating virus-induced physiological stress. The non-structural carbohydrates, total protein, and free proline contents were also significantly altered. More, the high accumulation of salicylic acid and other defense-related antioxidant enzymes (ascorbate peroxidase, guaiacol peroxidase, superoxide dismutase, and catalase) was observed to ameliorate virus-induced stress. An increase in polyphenols and flavonoids: gallic acid, protocatechuic acid, chlorogenic acid, caffeic acid, rutin, ferulic acid, quercetin, and kaempferol suggests the proactive action by BYMV-infected V. faba. A reduced accumulation of nutrition-related parameters while induced accumulation of anti-nutritional factors like tannin (as tannic acid) and phytate observed is suggestive of poor nutritional quality of the plants. The present study comprehensively elucidates the BYMV-induced perturbations in physio-biochemical and nutritional attributes of V. faba, diminishing the quality of plants and seeds, and raises serious concerns for the management measures against the BYMV.

Acca sellowiana (Myrtaceae) is a multipurpose species with edible fruits and ornamental value, native to Uruguay and southern Brazil. Domestication of the species in Uruguay is incipient although in other countries, it is widely cultivated. It is an evergreen out-crossing shrub, pollinated by birds and bees. For this reason, it is necessary to develop vegetative propagation strategies such as stem cuttings to reproduce outstanding genotypes for conservation or breeding programs. Adventitious root (AR) formation in cuttings is regulated by environmental and endogenous factors. Among phytohormones, indole-butyric acid (IBA) is the most widely exogenous auxin used to improve rooting of cuttings. Most studies on AR formation at the molecular level use model species; however, the conservation of these mechanisms in non-model plants has been little studied, consequently the effects of different factors and their interactions in A. sellowiana are not well understood. The identification and expression analysis of genes known to be involved in the regulation of the process is an important step to elucidate the molecular mechanisms that regulate AR differentiation in A. sellowiana cuttings. In this study, we compared two genotypes with contrasting rooting ability, and we identified and characterized three genes that might regulate the onset of AR development in A. sellowiana: AsPIN1, AsTIR1 and AsSHR. Their expression analysis showed that in the difficult-to-root genotype, AsTIR1 increases strongly in response to exogenous IBA, shortly after induction treatment. Relative expression of AsPIN1 and AsSHR also increases 24 h later. The biological significance of this gene expression pattern is discussed.

The evolutionary origin and diversification of flowers in angiosperms remain one of the great unsolved mysteries in plants, while the molecular genetics of floral organ development are the crucial aspect of this question. Here, the expression patterns of all 25 MIKC^C genes in various floral organs of Akebia trifoliata, including the stamens, carpels and sepals of both male and female flowers, were determined by qRT–PCR to preliminary explore the molecular mechanism of flowers development. The phenotypic characteristics of floral organs were also outlined. The results showed that A. trifoliata flowers were monoecious and unisexual. Neither female nor male flowers have petals, but petal-like sepals form the petaloid perianth, especially the curly and enlarged sepals in female flowers that compensate for the loss of petals. Multiple comparison analysis showed that 24 (96%) of the 25 MIKC^C genes exhibited significantly different expression levels between the leaves and floral organs. Further cluster analysis of the expression profiles showed that 11 genes were classified into a clade that mainly regulated the sepal development of male flowers, while the remaining 14 genes were classified into another clade that was associated with the development of other floral organs. These results suggested that many A. trifoliata MIKC^C genes had a broader expression boundary and weaker specificity than the classic ABC(D)E model and that both petaloidy of the perianth and dimorphism of the sepals could be related to rapid functional diversification and subfunctionalization.

The application of chemical amendment to improve metal availability is a key strategy in phytoremediation and an important determinant for successful removal of heavy metals from soil, although empirical data on their effects on plants used in phytoremediation are scanty. In this study, field-based assisted phytoremediation with ethylene-diamine-tetra-acetic acid (EDTA), nitrogen-potassium-phosphorus fertilizer (NPK) and combination of EDTA and NPK modelled after the completely randomized block design was used to determine the effects of chemical amendments on some morphological and physiological growth parameters of vetiver grass (Chrysopogon zizanioides (L.) Roberty) as well as the relative effects of chemical amendment and free heavy metal ions contamination. Results showed that the soil amendments (EDTA, NPK, EDTA + NPK) enhanced plant height and diameter, and reduced the toxicity of free metal ions. On the other hand, heavy metals reduced plant chlorophyll-a and -b, and plant root, and correlated with lipid peroxidation. Notably, EDTA contributed the least to enhancing plant height, diameter, and root length although it interacted positively with NPK to enhance the above-mentioned parameters. In general, the results of this study confirm the effectiveness of chemical amendments (EDTA and NPK in this case) in reducing the toxicity of free heavy metal ions in plant during phytoremediation.

Cymbidium ensifolium L. is an economically important terrestrial orchid. Leaf color is a key horticultural trait with aesthetic and ornamental significance. However, the molecular basis of leaf color change in C. ensifolium remains to be fully understood. Here, different color leaves of C. ensifolium were collected and classified into two groups, namely, leaf buds that appear red in the juvenile stage (RL) and those that transform green in the mature stage (GL). Significantly higher anthocyanin content was observed in RL than GL. RNA-seq data showed a total of 3955 differentially expressed unigenes (DEUs) were screened, and 381 differentially accumulated metabolites (DAMs) were detected by metabolome analysis in RL vs GL. Further analysis revealed that the anthocyanin biosynthesis pathway (ko00942) is essential for leaf color change. Cyanidin-3-O-glucoside, petunidin-3-O-(6″-O-p-coumaroyl) rutinoside, and peonidin-3-O-glucoside were identified as key anthocyanins affecting leaf color change. Meanwhile, we identified key structural unigenes associated with leaf color change, including CHS, CHI, DFR, F3H, F3′H, and ANS. Correlation analysis revealed 77 DEUs associated with transcription factors to exhibit strong correlations with both DEUs and DAMs involved in anthocyanin biosynthesis. Our study identifies the important metabolic and functional role of the anthocyanin biosynthesis pathway in C. ensifolium leaf color change.

The global agricultural productivity has been significantly impaired due to the extensive use of heavy metal. Cadmium (Cd) is now recognized as a significant soil and environmental contaminant that is primarily spread by human activity. This study investigates the possible impact of melatonin (ME) in mitigating the toxicity caused by Cd in pepper (Capsicum annuum L.) seedlings. There were three groups of plants used in the experiment: control (CK) plants, Cd-stressed plants and ME-pretreated + Cd-stressed plants. The concentration of ME and Cd was 1 µM and 0.1 mM, respectively, and applied as root application. The results described that Cd treatment remarkably reduced growth parameters, impaired pigment concentration, hindered gas exchange traits. In contrast, ME supplementation significantly recovered these parameters by increase in growth and biomass production of pepper seedlings under Cd toxicity. In addition, ME application considerably increased osmolyte production and protein level in pepper leaves and roots. Furthermore, ME positively upregulated the antioxidant enzymes activity and effectively decreased the oxidative damage in pepper leaves and roots. The enhanced antioxidant enzymes activity performed a significant role in the reduction of H₂O₂ and MDA concentration in plants under Cd stress. The findings indicated that the application of ME to plants effectively alleviates the stress caused by Cd exposure. Moreover, ME demonstrates significant efficacy in mitigating the adverse impacts of Cd on pepper plants.

Cotton production is tremendously impacted by the cotton leaf curl virus (CLCuV) in the Indian subcontinent. Viral infection modifies physiological and biochemical processes in plants, which leads to the appearance of symptoms. Hence, the current study was to discern the quantifiable changes in physiological and biochemical parameters in leaves of cotton plants graft inoculated with CLCuV on different days after infestation (DAI). The results revealed that in the CLCuV-infected plants, the relative water content (RWC) and total soluble protein were decreased. Some enzymes involved in the activities like anti-oxidative and defence mechanisms such as polyphenol oxidase (PPO), catalase (CAT), phenylalanine ammonia-lyase (PAL), and peroxidase (POX) were increased as the infestation period progressed with a concomitant increase in gossypol and total phenolic level. Contents of total soluble sugar, chlorophyll (Chl) along with hydrogen peroxide (H₂O₂) were increased initially and decreased afterwards in all genotypes. Correlation analysis elucidates that RWC is negatively associated with electrolyte leakage (EL) and malondialdehyde (MDA) content. In contrast, Chl content showed a positive correlation with total soluble proteins, secondary metabolites like phenol and gossypol, anti-oxidative and defence enzymes. Three principal components (PCs) were produced by the principal component analysis (PCA) contributing 87.33% of the total variability in various physiological and biochemical traits of different genotypes. Phenolics profiling reveals that concentrations of rutin hydrate in the infected sample increased by 49.6% compared to the control one. Overall, the findings imply that CLCuV infection causes substantial changes in enzyme levels that result in the development of unrectifiable symptoms in susceptible genotypes.

Current technologies have become a source of electromagnetic pollution resulting from artificially generated electromagnetic radiation (EMR). To understand the influence of the EMR on living organisms, we investigated the long-term effects of EMR of 50 Hz frequency on duckweed (Lemna minor) clones. Experimental groups of duckweed were treated directly and indirectly by changing EMR generating magnetic flux (MF) starting from 2 µT (0–11 weeks from the beginning of the experiment) and switching to 300 µT (12–48 weeks) MF density during the second part of the experiment. The growth parameters (plant growth, frond area, and frond number) and the point mutations appearing at the antioxidant genes DNA sequences [ascorbate peroxidase (APx), glutathione peroxidase (GPx), and catalase (Cat)] were analyzed. The significantly enhanced number of nucleotide substitutions in DNA sequences of L. minor clones directly affected by LF EMR in comparison to indirectly affected clones was revealed at the introns of APx, GPx, and Cat genes starting from the 10th week of the experiment. The results indicate that even low-dose chronic electromagnetic radiation may contribute to the changes in growth parameters and generation of point mutations in antioxidant gene sequences, especially in the intron regions.