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Background and aims: The impacts of macrovascular invasion (MVI) or extrahepatic spread (EHS) on the efficacy and safety of immune checkpoint inhibitors (ICIs) among hepatocellular carcinoma (HCC) patients remain unclear. Thus, we conducted a systematic review and meta-analysis to clarify whether ICI therapy is a feasible treatment option for HCC with MVI or EHS. Methods: Eligible studies published before September 14, 2022, were retrieved. In this meta-analysis, the objective response rate (ORR), progression-free survival (PFS), overall survival (OS), and occurrence of adverse events (AEs) were outcomes of interest. Results: Fifty-four studies involving 6187 individuals were included. The findings indicated that the presence of EHS in ICI-treated HCC patients may indicate an inferior ORR (OR 0.77, 95% CI 0.63–0.96), but may not significantly affect the PFS (multivariate analyses: HR 1.27, 95% CI 0.70–2.31) and OS (multivariate analyses: HR 1.23, 95% CI 0.70–2.16). Additionally, the presence of MVI in ICI-treated HCC patients may not have significant prognostic impact on ORR (OR 0.84, 95% CI 0.64–1.10), but may indicate inferior PFS (multivariate analyses: HR 1.75, 95% CI 1.07–2.84) and OS (multivariate analyses: HR 2.03, 95% CI 1.31–3.14). The presence of EHS or MVI in ICI-treated HCC patients may not significantly impact the occurrence of any serious immune-related adverse events (irAEs) (grades ≥ 3) (EHS: OR 0.44, 95% CI 0.12–1.56; MVI: OR 0.68, 95% CI 0.24–1.88). Conclusion: The presence of MVI or EHS in ICI-treated HCC patients may not significantly impact the occurrence of serious irAEs. However, the presence of MVI (but not EHS) in ICI-treated HCC patients may be a significant negative prognostic factor. Therefore, ICI-treated HCC patients with MVI warrant more attention. [ABSTRACT FROM AUTHOR]

Background: Tumor vaccines for hepatocellular carcinoma (HCC) is an area of intense interest. Tremendous clinical trials have been conducted globally, but the efficacy and security of tumor vaccines are elusive. The aim of our study was to evaluate the efficacy and security of tumor vaccines. Methods: All relevant studies were identified in PubMed, EMBASE, Web of science and Cochrane Library databases. Objective response rate (ORR), median overall survival (OS), or median progression-free survival (PFS) and 95% CI were meta-analyzed based on the random-effects model. The individual-level data of OS, PFS were pooled by conducting survival analysis. All observed adverse events were collected. Results: 31 studies containing 35 eligible cohorts with 932 HCC patients were included. The pooled ORR were 7% (95% CI 3–14%), while ORR of dendritic cell (DC) vaccine (19%, 95% CI 11–29%) were highly significant than ORR of peptide vaccine (1%, 95% CI 0–5%). The pooled median OS and PFS were 13.67 months (95% CI 8.20–22.80) and 6.19 months (95% CI 2.97–12.91), respectively. The pooled median OS (DC vaccine: median OS = 21.77 months, 95% CI 18.33–25.86; Peptide vaccine: median OS = 10.08 months, 95% CI 5.23–19.44) and PFS (DC vaccine: median PFS = 11.01 months, 95% CI 5.25–23.09; Peptide vaccine: median PFS = 1.97 months, 95% CI 1.53–2.54) of DC vaccine were also longer than that of peptide vaccine. HBV-related HCC may acquire more benefits from tumor vaccines than HCV-related HCC. In almost all studies, the observed toxicities were moderate even tiny. Conclusions: Tumor vaccines for HCC, especially DC vaccine, are safe and worth exploring. More high-quality prospective studies are warranted. [ABSTRACT FROM AUTHOR]

Simple Summary: Hepatocellular carcinoma is one of the most lethal malignancies, having a significantly poor prognosis. Immunotherapy, as an emerging tumor treatment option, provides new hope for many cancer patients. However, a large proportion of patients do not benefit from immunotherapy. As a critical cell-to-cell communication mediator in the tumor immune microenvironment, exosomes may play a unique role in hepatocellular carcinoma immune response and thus affect the efficiency of immunotherapy. In this review, we discuss related research on the roles of exosomes in the current immunotherapy resistance mechanism of hepatocellular carcinoma. Furthermore, we also clarify the excellent predictive value of exosomes and the roles they play in improving immunotherapy efficacy for hepatocellular carcinoma patients. We hope that our review can help readers to gain a more comprehensive understanding of exosomes' roles in hepatocellular carcinoma immunotherapy. Hepatocellular carcinoma (HCC) is one of the most lethal malignancies, having a significantly poor prognosis and no sufficiently efficient treatments. Immunotherapy, especially immune checkpoint inhibitors (ICIs), has provided new therapeutic approaches for HCC patients. Nevertheless, most patients with HCC do not benefit from immunotherapy. Exosomes are biologically active lipid bilayer nano-sized vesicles ranging in size from 30 to 150 nm and can be secreted by almost any cell. In the HCC tumor microenvironment (TME), numerous cells are involved in tumor progression, and exosomes—derived from tumor cells and immune cells—exhibit unique composition profiles and act as intercellular communicators by transporting various substances. Showing the dual characteristics of tumor promotion and suppression, exosomes exert multiple functions in shaping tumor immune responses in the crosstalk between tumor cells and surrounding immune cells, mediating immunotherapy resistance by affecting the PD-1/PD-L1 axis or the anti-tumor function of immune cells in the TME. Targeting exosomes or the application of exosomes as therapies is involved in many aspects of HCC immunotherapies (e.g., ICIs, tumor vaccines, and adoptive cell therapy) and may substantially enhance their efficacy. In this review, we discuss the impact of exosomes on the HCC TME and comprehensively summarize the role of exosomes in immunotherapy resistance and therapeutic application. We also discuss the potential of exosomes as biomarkers for predicting the efficacy of immunotherapy to help clinicians in identifying HCC patients who are amenable to immunotherapies. [ABSTRACT FROM AUTHOR]

Highlights • Highest alfalfa forage yield was obtained for P applied at 16 kg P ha−1 with film mulch. • Forage yield in mulched field decreased when P applied exceeded 16 kg P ha−1. • Higher P level decreased SOC mineralization and soil N availability in mulched field. • Decreased forage yield in high P with mulching was related to low soil N availability. • Film mulch lead to high alfalfa production with P-saving and low risk of N loss. Abstract Plastic film mulch and phosphorus (P) fertilization usually increase alfalfa (Medicago sativa L.) forage yield in semi-arid regions by improving soil moisture and P availability. However, this does not always occur. The present study explored the P level for highest forage yield under film mulch and the mechanism underlying yield decrease at high P levels. A six-year study was conducted with randomized blocks of split-plot design with and without plastic film mulch as main plots: M0, no film mulch with flat planting; and M1, film mulching with ridge-furrow field regimes. Four P rates were applied in sub-plots: P0, P1, P2 and P3 with 0, 9.73, 19.3 and 28.9 kg P ha–1, respectively. Film mulch greatly increased forage yield, resulting in 14% higher yield in M1P0 than in M0P3. Forage yield under mulching decreased for 19.3 and 28.9 kg P ha−1. The P rate for maximum yield was 16.1 kg P ha−1. Soil total nitrogen (N) and inorganic-N decreased at 19.3 and 28.9 kg P ha−1 with mulching compared with 9.73 kg P ha−1, and the latter was about 90% lower than that of alfalfa lands in semi-humid region. Soil microbial biomass carbon (C) and C/N ratio in microbial biomass in mulched P2 and P3 subplots were significantly lower than for P1. With mulching, soil organic C mineralization was significantly less for P3 than for P1 and P2. Shoot N/P ratio decreased with increasing P with mulching. Thus shoot N uptake for P2 and P3 mulched plots was associated with low soil N availability. It is concluded that the highest forage yield was obtained with mulching, P-saving and low risk of N loss on the semiarid Loess Plateau. [ABSTRACT FROM AUTHOR]

Temperatures are predicted to increase in semi-arid regions, which will affect the frequency of some climatic events such as freeze–thaw cycles. To understand the impact of recurrent freezing and thawing on soil microorganisms and their environment, three soils from diverse land-use types (grassland, cut grassland and cropland) in the semi-arid area of the Loess Plateau were subjected to two different freeze–thaw cycles (FTC) for 48 days (either 4 days each at −2 °C and +3 °C for 6 FTC or 8 days each at −2 °C and +3 °C for 3 FTC). Nutrient content and mobilization in the soil, and microbial biomass and functional diversity were examined. When subjected to these freeze–thaw cycles, soil respiration was low during the −2 °C phase and high during the +3 °C phase, decreasing in successive cycles, which indicates the rapid response of microbial activity even after long exposure to fluctuating temperatures. Soil respiration stabilized after 32 days in the three soils in the treatment with 3 FTC but continued to decrease in the treatment with 6 FTC. With each successive freeze–thaw cycle, microbial biomass C and N decreased gradually in all the tested soils. At the end of the experiment, the 6 FTC treatment had more microbial biomass C and N than the 3 FTC treatment in each soil type, indicating that microbial activity (respiration) was controlled mainly by the rapid freeze–thaw cycles rather than microbial biomass. Soil inorganic N concentration declined in all soils subjected to 6 FTC but increased when subjected to only 3 FTC, suggesting that the surviving microorganisms in the treatment with 6 FTC had more potential for using soil N to adapt to the freeze–thaw stress. The microbial functional diversity in the three tested soil types in response to the two freeze–thaw cycle treatments varied, suggesting differences in the native microbial communities in the soil from various land-use types. [ABSTRACT FROM AUTHOR]

Alfalfa ( Medicago sativa L.) is an important forage legume in farming and animal husbandry systems in semiarid areas. However, its forage yields in dryland farming areas are usually very low due to water shortages and low soil phosphorus (P) availability. This study assessed the effects of plastic film mulch and P fertilization on alfalfa forage yield and shoot P uptake in response to improved soil moisture and soil P availability in a dryland farming system of northwest China. A six-year field experiment, which commenced in 2011, was conducted at Yuzhong County, Gansu Province, China in randomized blocks of split-plot design with two mulch treatments—plastic film mulch with ridge and furrow (M) and no plastic film mulch with flat planting (NM)—as the main plots, and four P levels—0, 9.73, 19.3, 28.9 kg P ha −1 —as split plots. Alfalfa forage yield and shoot P uptake and concentration increased linearly with increasing P level in the NM treatment. In the M treatment, shoot P concentration also increased linearly with increasing P level, but shoot P uptake and forage yield were well-fitted by a quadratic model with P level as the independent variable and a lower physiological P use efficiency at high P level. Alfalfa forage yield and water use efficiency increased with plastic film mulch. Soil water content in the upper 1 m of soil increased with plastic film mulch and was higher in the 2014 growing season and in April 2015 due to more rainfall. However, at 1–5 m soil depth, the soil water content decreased with plastic film mulch and P fertilization but increased at high P levels with plastic film mulch. Soil pH decreased with plastic film mulch and P fertilization, with a stronger effect from the latter, which is beneficial for improving soil P availability. Soil available P, mostly derived from inorganic P, increased with P fertilization and was lower in M than NM treatments due to alfalfa uptake and competition with soil microorganisms. We concluded that plastic film mulch and P fertilization, of about 16.1 or 17.5 kg P ha −1 , was an appropriate combination to improve soil water condition and soil P availability for increased alfalfa forage yield or shoot P uptake in this semiarid region. [ABSTRACT FROM AUTHOR]

Background and Aim Methods Results Conclusions The purpose of the current study was to investigate the predictive value of hepatitis B core‐related antigen (HBcrAg) on the occurrence and recurrence of hepatocellular carcinoma (HCC) in patients with chronic hepatitis B (CHB).We searched PubMed, Embase, Scopus, and Web of Science from database inception to April 6, 2023. Pooled hazard ratio (HR) or odds ratio (OR) with 95% confidence interval (CI) was calculated for the occurrence and recurrence of HCC.Of the 464 articles considered, 18 articles recruiting 10 320 patients were included. The pooled results showed that high serum HBcrAg level was an independent risk factor for the occurrence of HCC in CHB patients (adjusted HR = 3.12, 95% CI: 2.40–4.06, P < 0.001, I2 = 43.2%, P = 0.043; OR = 5.65, 95% CI: 3.44–5.82, P < 0.001, I2 = 0.00%, P = 0.42). Further subgroup analysis demonstrated that the predictive ability of HBcrAg for the occurrence of HCC is not influenced by the hepatitis B e antigen (HBeAg) status or the use of nucleoside/nucleotide analogs (NAs). In addition, our meta‐analysis also suggests that HBcrAg is a predictor of HCC recurrence (adjusted HR = 1.71, 95% CI: 1.26–2.32, P < 0.001, I2 = 7.89%, P = 0.031).For patients with CHB, serum HBcrAg may be a potential predictive factor for the occurrence of HCC, regardless of HBeAg status or NA treatment. It may also serve as a novel prognostic biomarker for the recurrence of HCC. More studies are needed to confirm our conclusions. [ABSTRACT FROM AUTHOR]

Abstract: In this paper we modified a spray method to visualize iodide water tracer in calcareous soil with high pH, and developed a process to combine multiple soil horizontal sections to establish three-dimensional (3-D) visualization modeling for water-flow paths in soil. In the modified spray method, pH adjuster was misted onto the soil surface to lower soil pH after starch solution with oxidizer (ferric ion) had been sprayed onto the soil profile irrigated by iodide-labeled water. The acidic condition accelerated the distinct purple–blue color of iodine–starch. When images of multiple soil horizontal sections stained by iodine–starch complex were captured by digital camera, the iodine–starch color stained pattern on the soil surface was outlined using software ImageJ (developed at the US National Institutes of Health). After all 3-D coordinates were outlined with dots, 3-D visualization modeling for water-flow paths in soil was established using software Surfer 8.0 (Golden Software Inc.) as an alternative method for studying water infiltration and distribution behavior in soil. [Copyright &y& Elsevier]

The introduction of immune checkpoint inhibitors (ICIs) has reshaped the therapy of hepatocellular carcinoma (HCC). ICIs are a novel therapy with frequent adverse events (AEs), including treatment-related adverse events (trAEs) and immune-related adverse events (irAEs). However, no comprehensive overview of the toxicity spectrum of ICIs in HCC patients has been provided. Electronic databases were searched to identify eligible studies. A meta-analysis of the incidence rate of AEs in HCC patients treated with ICIs was performed. Lastly, the prognostic value of irAEs in HCC patients treated with ICIs was verified. Forty-seven studies with 6472 participations met the inclusion criteria. The pooled all-grade trAEs incidence rate was 83.4% (95% confidence interval [95% CI] 77.0–89.1%), ≥ grade 3 trAEs incidence rate was 33.0% (95% CI 26.9–39.5%), all-grade irAEs incidence rate was 34% (95% CI 22–47%), and ≥ grade 3 irAEs incidence rate was 9% (95% CI 5–14%). Aspartate aminotransferase (AST) increase (38%, 95% CI 35–40%) is the most common trAEs. Fatigue (14%, 95% CI 7–23%) is the most common irAEs. The pooled results also showed that 18.8% (95% CI 13.2–25.2%) of patients required systemic steroid therapy due to AEs, while 6.6% (95% CI 4.6–9.0%) of patients withdrew from treatment due to AEs. Additionally, patients experiencing irAEs may have a better progression-free survival (PFS) (multivariate analysis: hazard ratio [HR] = 0.41, 95% CI 0.27–0.61, I2 = 36.3%) but not overall survival (OS) (multivariate analysis: HR = 0.54, 95% CI 0.22–1.36, I2 = 83.2%) than those with no irAEs. Our study presents a systemic assessment of the AEs profile in HCC patients receiving ICIs, providing important reference for clinicians on toxicity profile. Besides, patients with irAEs may have a better PFS. More large-scale and prospective studies are needed to confirm our conclusions. [ABSTRACT FROM AUTHOR]

• The RET gene, which is frequently mutated across many cancer types, has been proven to be involved in tumorigenesis. • However, its prediction of the therapeutic efficacy of immune checkpoint inhibitor (ICIs) therapy remains to be elucidated. • The present research aims to investigate the association between RET mutations and the efficiency of ICIs therapy. The RET gene, which is frequently mutated across many types of cancer, has been proven to be critically involved in tumorigenesis and tumour development; however, its prediction of the therapeutic efficacy of immune checkpoint inhibitor (ICI) therapy remains to be elucidated. The present research aims to investigate the association between RET mutations and the efficiency of ICI therapy. We analysed the role of RET mutations in predicting the prognosis of patients receiving ICIs therapy in the discovery cohort and validated it in the validation cohort. Then, multi-omics data from TCGA pan-cancer cohort was employed to propose the association between RET mutations and tumour inflamed anti-tumour immune response and tumour antigenicity. Our study revealed that among 606 cases and across five types of cancer, RET mutation was associated with better clinical outcomes for ICIs therapy, including elevated response rate, longer progression-free survival PFS, and longer overall survival OS. Multivariate analysis showed that RET mutation could independently predict the prognosis of patients treated with ICIs, after adjusting cancer types. The predictive value of RET status for the OS of patients treated with ICIs immunotherapy was further validated in the validation cohort (n = 1,409). Subgroup analysis suggested that only the monotherapy group showed significant differences in OS(P < 0.05) and PFS(P < 0.05) between RET -wildtype tumours and RET -mutant tumours. Multi-omics data analysis revealed potential anti-tumour immunity mechanisms of RET mutations, suggesting that RET -mutant tumours have enhanced immunogenicity, higher expression of immune checkpoints and chemokines, and higher immune cell infiltration than those observed in RET -wildtype tumours; thus, potentially indicating a more favourable response to immunotherapy. RET mutation may be a predictive biomarker of enhanced response to ICIs therapy. Extensive investigation of the underlying molecular mechanisms and prospective studies are needed in the future. [ABSTRACT FROM AUTHOR]

The present study investigated the sensitization of 5-fluorouracil (5-FU)-resistant colon cancer cells in vitro, using oxymatrine, a Chinese herb, and a quinolizidine alkaloid compound extracted from the root of Sophora flavescens. The HCT-8 colon cancer cell line and its 5-FU-resistant subline HCT-8/5-FU were treated with 5-FU and oxymatrine, alone or in combination, at various doses. The cells were subsequently assessed for changes in cell viability, apoptosis and morphology and analyzed by fluorescence microscopy and western blotting. The data demonstrated that HCT-8/5-FU markedly increased the dose of 5-FU required for the suppression of tumor cell viability (78.77±1.90 µg/ml vs. 9.20±0.96 µg/ml in parental HCT-8 cells), whereas HCT-8/5-FU induced the tumor cell epithelial-mesenchymal transition (EMT). By contrast, oxymatrine alone and in combination with 5-FU altered HCT-8/5-FU cell morphology, apoptosis and EMT phenotypes. The combination of oxymatrine and 5-FU reduced the protein expression of snail family transcriptional repressor 2 and vimentin, phosphorylated p65 and induced the expression of E-cadherin, by inhibiting the nuclear factor κB (NF-κB) signaling pathway. In conclusion, the data from the present study demonstrated that EMT was associated with 5-FU chemoresistance in HCT-8/5-FU colon cancer cells, and that oxymatrine treatment was able to reverse such resistance. Oxymatrine may regulate tumor cell EMT and inactivate the NF-κB signaling pathway, and may therefore serve as a potential therapeutic drug to reverse 5-FU resistance in colon cancer cells. [ABSTRACT FROM AUTHOR]

In semi-arid areas, alfalfa (Medicago sativa L.) is widely grown, but its growth is often restricted due to limited rainfall and soil nutrients, particularly phosphorus (P). Nutrient resorption is an effective strategy for dealing with nutrient shortages. Alleviation of these limited resources using film mulch and P fertilization—which are common practices in semi-arid areas—can affect the internal recycling of such nutrients. Little is known about such effects in alfalfa and the relationship between resorption efficiency and forage yield. We conducted a two-year field experiment in the semi-arid Loess Plateau of China using film mulch and P fertilization to investigate the response to long-term increasing soil water and P availability on leaf nitrogen (N), P, and potassium (K) concentrations and nutrient resorption characteristics in alfalfa. In green leaves, mulching significantly increased P concentration by an average of 5.5% but it had no significant effect on N concentration over two years, and it decreased K concentration by 16.1% in 2017. P fertilization significantly increased N concentrations to a greater degree in 2018 (8.1%) than 2017 (1.6%). P fertilization also significantly increased P concentrations by an average of 34.1% over two years. In contrast, P fertilization significantly decreased K concentration in the mulched treatment by an average of 17.3% in 2017 and 21.8% in 2018, but it had no effect in the no-mulch treatment. In senescent leaves, mulching significantly increased N concentration by an average of 3.9% and P concentration by an average of 16.7%, but it had no significant effect on K concentration over two years, while P fertilization significantly decreased N and K concentrations over two years by an average of 7.5%, and 32.8%, respectively. P fertilization significantly increased senesced P concentration by an average of 11.9% in 2017 and 17.5% in 2018; and year × mulching × P fertilization had a significant interaction on senesced leaf P concentration. For resorption efficiency, mulching decreased P resorption efficiency by an average of 3.0%, but it had no impact on N or K resorption efficiency, while P fertilization increased the N, P, and K resorption efficiencies in alfalfa by an average of 6.8%, 6.2%, and 76.4% over two years, respectively. Interactive effects of mulching and P fertilization were found on P and K resorption efficiencies over time. In addition, N and K resorption efficiencies were significantly higher in 2018 than in 2017. The application of P fertilizer without mulching resulted in positive correlations between forage yield and N, P, and K resorption efficiencies, but no correlations were observed under film mulch. That is, mulching changed the relationship between forage yield and N, P, and K resorption efficiencies in alfalfa, suggesting that N, P, and K resorption efficiencies may not be related to high yield. Our results provide new insights into the role of nutrient resorption in alfalfa in response to increasing soil water and P availability and the relationship between resorption efficiency and forage yield, which will help us to improve alfalfa yield in semi-arid regions. [ABSTRACT FROM AUTHOR]

• Hepatocellular carcinoma patients with impaired liver function have poor prognosis after receiving ICIs. • Both ALBI score and Child-Pugh score can stratify HCC patients. • ALBI score is simpler and more reliable for patient stratification than Child-Pugh score. • The incidence of adverse events is not significantly increased in impaired liver function patients. Most patients with hepatocellular carcinoma (HCC) have underlying cirrhosis and a compromised liver function. Immune checkpoint inhibitors (ICIs) have emerged as an important approach for HCC treatment. The purpose of our study was to explore the prognostic significance of liver function in HCC patients receiving ICIs. Hazard ratios (HR) with 95% confidence intervals (CI) were used to evaluate the relationship between liver function and overall survival (OS)/progression-free survival (PFS). 41 articles with 4483 patients with HCC were included. The pooled results revealed that either Child-Pugh score (OS:HR = 2.01,95 %CI:1.69–2.38; PFS:HR = 1.39,95 %CI:1.15–1.68) or albumin-bilirubin (ALBI) score (OS:HR = 2.04,95 %CI:1.55–2.69; PFS:HR = 1.42,95 %CI:1.21–1.67) can predict the patient prognosis. The Child-Pugh score has some degree of subjectivity, and the ALBI score can better stratify patients. Therefore, the ALBI score was used to evaluate patients' liver function and determine treatment options. Further subgroup analysis found that the results of prospective studies were statistically significant only for the ALBI score with regards to OS (HR = 1.69,95 %CI:1.26–2.26). Meanwhile, the effect of liver function on the efficacy of ICIs in the large-sample studies was not as obvious as that in small-sample studies. Moreover, the incidence of adverse events did not significantly increase in patients with impaired liver function. Poor liver function is associated with a poor prognosis in patients with HCC receiving ICIs. The ALBI score is simpler and reliable for patient stratification than the Child-Pugh score. Although the survival time of patients with impaired liver function may be relatively short, ICIs still have great potential for therapeutic applications. [ABSTRACT FROM AUTHOR]

Film mulch increases the crop grain yield via topsoil moisture and temperature improvement in cool, semi-arid areas, but little is known about the role of the hydrological and thermic relationship between early and later crop growth seasons in the improving grain yield. We conducted a field experiment to compare polyethylene film mulching (PM) with no mulching (CK) in 2014 and 2015 on the semi-arid Loess Plateau of China. Compared to CK, PM decreased evapotranspiration before the twelve-leaf stage (V12), but increased evapotranspiration after the V12 stage, and significantly increased the topsoil temperature before the six-leaf stage (V6) and the accumulation of soil growing degree days. Corn plants with PM treatment reached the V6 stage earlier, significantly enhancing the contemporary dry matter accumulation. The harvest index, 100-grain weight, and grain yield significantly increased in PM relative to CK in both years. The growing period to the whole growing season evapotranspiration ratio had a negative correlation with the grain yield before the V12 stage, but a positive correlation after the V12 stage. The grain yield had a negative correlation with the air growing degree days (GDDair) before the V6 stage, but positive correlation from silking to harvest. Conclusively, film mulch promoted the early development of maize via an increased soil temperature before the V6 stage, saved soil water before the V12 stage, resulted in a longer grain-filling period, and increased the GDDair and evapotranspiration during the grain-filling period, which is key to increasing the maize yield. [ABSTRACT FROM AUTHOR]