exogenous treatment
Recently Published Documents


TOTAL DOCUMENTS

67
(FIVE YEARS 33)

H-INDEX

12
(FIVE YEARS 5)

2021 ◽  
Vol 13 (24) ◽  
pp. 14012
Author(s):  
Yingying Wang ◽  
Wenjuan Song ◽  
Bo Zhang ◽  
Robert L. K. Tiong

PPP withdrawal policy is helpful to reduce over-investment in PPPs leading to sustainable development. However, little is known about the role of local governments on over-investment in PPPs. Using the PPP Project Platform Data, a unique dataset, this article is able to quantify over-investment in PPPs by coding PPP withdrawal for the first time. This research tests the influencing factors of PPP withdrawal at the municipal level, according to the centralized withdrawal policy in late 2017 as an exogenous treatment. Based on the theory of over-investment to rapid economic growth, this study develops a two-pillar framework under the combination of political man and economic man assumptions to explain the PPP withdrawal of local governments. The results show that both official tenure and fiscal capacity are significant factors. In addition, debt partially mediates the mayor tenure on PPP withdrawal, and the land revenue growth can hinder the negative relationship between mayor tenure and PPP withdrawal. It implies that over-investment in PPPs is strongly influenced by official leaders’ personal promotion incentive and official group members’ collective benefit. Thus, our findings indicate that the centralized withdrawal policy is an effective instrument to prevent over-investment in PPPs. Moreover, a match should be formed between local development planning and investment plans to promote sustainable of PPP investment.


2021 ◽  
Vol 22 (23) ◽  
pp. 12676
Author(s):  
Chenlu Liu ◽  
Hongtao Wang ◽  
Xiuzhi Zhang ◽  
Fengwang Ma ◽  
Tianli Guo ◽  
...  

Drought seriously affects the yield and quality of apples. γ-aminobutyric acid (GABA) plays an important role in the responses of plants to various stresses. However, the role and possible mechanism of GABA in the drought response of apple seedlings remain unknown. To explore the effect of GABA on apple seedlings under drought stress, seedlings of Malus hupehensis were treated with seven concentrations of GABA, and the response of seedlings under 15-day drought stress was observed. The results showed that 0.5 mM GABA was the most effective at relieving drought stress. Treatment with GABA reduced the relative electrical conductivity and MDA content of leaves induced by drought stress and significantly increased the relative water content of leaves. Exogenous GABA significantly decreased the stomatal conductance and intercellular carbon dioxide concentration and transpiration rate, and it significantly increased the photosynthetic rate under drought. GABA also reduced the accumulation of superoxide anions and hydrogen peroxide in leaf tissues under drought and increased the activities of POD, SOD, and CAT and the content of GABA. Exogenous treatment with GABA acted through the accumulation of abscisic acid (ABA) in the leaves to significantly decrease stomatal conductance and increase the stomatal closure rate, and the levels of expression of ABA-related genes PYL4, ABI1, ABI2, HAB1, ABF3, and OST1 changed in response to drought. Taken together, exogenous GABA can enhance the drought tolerance of apple seedlings.


2021 ◽  
Vol 845 (1) ◽  
pp. 012050
Author(s):  
T A Belova ◽  
M V Protasova

Abstract This article presents the results of studies reflecting the influence of the technology of effective microorganisms (TEM) on the development of plants of the Fabaceae family (Pisum sativum L.). The assessment of the real effectiveness of EM agents in the mild climate of the Central Black Earth region and their influence on field germination and morphophysiological parameters of plants is given. The theoretical foundations of the use of EM agents, their role in the formation of soil microbiological communities and the assessment of their impact as a factor influencing the efficiency of legume-rhizobium symbiosis are presented. The exogenous treatment with biological products significantly increased the number and mass of active nodules on experimental plants, which contributed to the increase in nitrogen-fixing activity, which was an important component for legumes. The authors pay due attention to the assessment of the parameters of photosynthetic activity of plants under the conditions of increased inoculation with microorganisms. Not only an increase in leaf area was noted, but also a longer functioning of the photosynthetic apparatus, which led to an increase in the intensity of the work of the green surface of plants during the entire growing season. The combination of stimulating factors provided a better increase in dry biomass, which was reflected in a significant increase in the value of plant yield. The most intense accumulation of dry matter was observed in the flowering phase, which was also characterized by more intensive inoculation of plants. At the end of the growing season, this was reflected in an increase in the number of beans per plant and seeds in one bean, which had a positive effect on the crop yield indicators. The research results indicate the prospects of the use of the technology of effective microorganisms in plant growing and agriculture for the production of environmentally friendly food products and soil fertility recovery.


2021 ◽  
Vol 19 (3) ◽  
pp. 197-208
Author(s):  
Kira A. Ivanova ◽  
Viktor E. Tsyganov

BACKGROUND: Polyamines are acting as signaling molecules during adaptation to stressful environment and as regulators of plant development. In plants, polyamines are represented mainly by putrescine, spermidine and spermine. The concentration of polyamines in symbiotic nodules of some legumes is 510 times higher than in the other organs, which indicates their important role in the formation and functioning of symbiotic nodules. MATERIALS AND METHODS: We analyzed the expression of genes encoding polyamine biosynthesis enzymes in symbiotic nodules, as well as the effect of exogenous polyamines on the nodule number and the average nodule weight in wild-type SGE plants and symbiotic pea mutants SGEFix-1 (sym40-1) and SGEFix-2 (sym33-3). RESULTS: The comparable expression level of arginine decarboxylase gene (PsADC) was observed in all analyzed nodules, whereas the expression level of ornithine decarboxylase gene (PsODC), was highly increased in nodules of SGEFix-2 (sym33-3) mutant. Treatment of the root system with a 0.1 mM solution of polyamines mixture led to an increase in the average weight of the nodule in wild-type plants and in the SGEFix-2 (sym33-3) mutant plants. CONCLUSIONS: It was shown that the main pathway of putrescine synthesis in wild-type pea symbiotic nodules is the arginine pathway, while the ornithine pathway is probably associated with activation of plant defense reactions. Polyamines acting, apparently, through ethylene, affect the functioning of the nodule meristem.


2021 ◽  
Author(s):  
Poorwa Kamal Badola ◽  
Aashish Sharma ◽  
Himanshi Gautam ◽  
Prabodh Kumar Trivedi

Small molecules, peptides, and miRNAs are the crucial regulators of plant growth. Here, we show the importance of cross-talk between miPEP858a/miR858a and Phytosulfokine (PSK4) in regulating plant growth and development in Arabidopsis. Genome-wide expression analysis suggested modulated expression of PSK4 in miR858 mutant and overexpression, miR858OX, plants. The silencing of PSK4 in miR858OX plants compromised the growth, whereas over-expression of PSK4 in miR858 mutant rescued the developmental defects. The exogenous application of synthetic PSK4 further complemented the plant development in mutant plants. Exogenous treatment of synthetic miPEP858a in PSK4 mutant led to clathrin-mediated internalization of the peptide however did not enhance growth as in the case of wild-type plants. We also demonstrate that the MYB3 is an important molecular component participating in miPEP858a/miR858a-PSK4 module. Finally, our work highlights the signaling between miR858/miPEP858-MYB3-PSK4 in modulating the expression of key elements involved in auxin responses leading to the regulation of growth.


2021 ◽  
Author(s):  
S. Carson Callahan ◽  
Margarita Divenko ◽  
Praveen Barrodia ◽  
Anand K Singh ◽  
Emre Arslan ◽  
...  

ABSTRACTHead and neck squamous cell carcinoma (HNSCC) is the sixth most common cancer worldwide, with 5-year survival of ∼50%. Genomic profiling studies have identified important somatic mutations in this disease which presents an opportunity for precision medicine. We demonstrate that KMT2D, a histone methyltransferase harbors somatic mutations in ∼17% of HNSCC and is associated with 2-year recurrence in TCGA data. Consistent with algorithmic prediction of bring a driver tumor-suppressor event, its loss results in larger oral tumors in immune-proficient orthotopic models. Mechanistically, we find that KMT2D knockdown or KMT2D mutation causes loss of H3K4me1-marked enhancers harboring IRF7/9 binding sites, which is known to regulate interferon signaling. Indeed, KMT2D loss in human and murine cell lines deregulated transcriptional levels of cytokine expression and impacted numerous immune signaling pathways, including interferon signaling. Consistently, Kmt2d knockdown in murine tumors exhibited decrease in IFNγ-producing effector T cells and an increase in T-cells with an exhausted phenotype. Epistasis experiments showed that exogenous treatment with IFNγ abrogated the increased tumor growth in Kmt2d-deficient oral tumors. Together, these results support the role of KMT2D as a tumor suppressor in HNSCC that regulates the tumor microenvironment by modulating H3K4me1-marked enhancers controlling interferon signaling.


2021 ◽  
Vol 22 (17) ◽  
pp. 9115
Author(s):  
Yunlei Zhao ◽  
Huijuan Jing ◽  
Pei Zhao ◽  
Wei Chen ◽  
Xuelin Li ◽  
...  

Verticillium wilt (VW) is a typical fungal disease affecting the yield and quality of cotton. The Trichome Birefringence-Like protein (TBL) is an acetyltransferase involved in the acetylation process of cell wall polysaccharides. Up to now, there are no reports on whether the TBL gene is related to disease resistance in cotton. In this study, we cloned a cotton TBL34 gene located in the confidence interval of a major VW resistance quantitative trait loci and demonstrated its relationship with VW resistance in cotton. Analyzing the sequence variations in resistant and susceptible accessions detected two elite alleles GhTBL34-2 and GhTBL34-3, mainly presented in resistant cotton lines whose disease index was significantly lower than that of susceptible lines carrying the allele GhTBL34-1. Comparing the TBL34 protein sequences showed that two amino acid differences in the TBL (PMR5N) domain changed the susceptible allele GhTBL34-1 into the resistant allele GhTBL34-2 (GhTBL34-3). Expression analysis showed that the TBL34 was obviously up-regulated by infection of Verticillium dahliae and exogenous treatment of ethylene (ET), and salicylic acid (SA) and jasmonate (JA) in cotton. VIGS experiments demonstrated that silencing of TBL34 reduced VW resistance in cotton. We deduced that the TBL34 gene mediating acetylation of cell wall polysaccharides might be involved in the regulation of resistance to VW in cotton.


Author(s):  
Yong-Soon Park ◽  
Eli J Borrego ◽  
Xiquan Gao ◽  
Shawn A Christensen ◽  
Eric Schmelz ◽  
...  

Seed maceration and contamination with mycotoxin fumonisin inflicted by Fusarium verticillioides is major disease of concern for maize producers world-wide. Meta-analyses of QTL for Fusarium ear rot resistance uncovered several ethylene (ET) biosynthesis and signaling genes within them, implicating ET in maize interactions with F. verticillioides. We tested this hypothesis using maize knock-out mutants of the 1-aminocyclopropane-1-carboxylate (ACC) synthases, ZmACS2 and ZmACS6. Infected wild-type seed emitted five-fold higher ET levels compared to controls, whereas ET was abolished in the acs2 and acs6 single and double mutants. The mutants supported reduced fungal biomass, conidia and fumonisin content. Normal susceptibility was restored in the acs6 mutant with exogenous treatment of ET precursor, ACC. Subsequently, we showed that fungal G-protein signaling is required for virulence via induction of maize-produced ET. F. verticillioides Gβ subunit and two regulators of G-protein signaling mutants displayed reduced seed colonization and decreased ET levels. These defects were rescued by exogenous application of ACC. We concluded that pathogen-induced ET facilitates F. verticillioides colonization of seed, and in turn host ET production is manipulated via G-protein signaling of F. verticillioides to facilitate pathogenesis.


2021 ◽  
pp. 002073142110248
Author(s):  
Elias Nosrati ◽  
Lawrence P. King

Geographical inequalities in life and death are among the world's most pronounced in the United States. However, the driving forces behind this macroscopic variation in population health outcomes remain surprisingly understudied, both empirically and theoretically. The present article steps into this breach by assessing a number of theoretically informed hypotheses surrounding the underlying causes of such spatial heterogeneity. Above and beyond a range of usual suspects, such as poverty, unemployment, and ethno-racial disparities, we find that a hitherto neglected explanans is prison incarceration. In particular, through the use of previously unavailable county-level panel data and a compound instrumentation technique suited to isolating exogenous treatment variation, high imprisonment rates are shown to substantially increase the population-wide risk of premature death. Our findings contribute to the political economy of population health by relating the rise of the carceral state to the amplification of geographically anchored unequal life chances.


Sign in / Sign up

Export Citation Format

Share Document