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Talaromyces purpurogenus, an endophytic fungus, exhibits beneficial effects on plants during plant–fungus interactions. However, the molecular mechanisms underlying plants' responses to T. purpurogenus under low-phosphorous (P) stress are not fully understood. In this study, we investigated the transcriptomic changes in maize with low-P-sensitive (31778) and -tolerant (CCM454) genotypes under low-P stress and its symbiotic interaction with T. purpurogenus. Its colonization enhanced plant growth and facilitated P uptake, particularly in 31778. Transcriptome sequencing revealed that 135 DEGs from CCM454 and 389 from 31778 were identified, and that only 6 DEGs were common. This suggested that CCM454 and 31778 exhibited distinct molecular responses to T. purpurogenus inoculation. GO and KEGG analysis revealed that DEGs in 31778 were associated with nicotianamine biosynthesis, organic acid metabolic process, inorganic anion transport, biosynthesis of various secondary metabolites and nitrogen metabolism. In CCM454, DEGs were associated with anthocyanin biosynthesis, diterpenoid biosynthesis and metabolic process. After T. purpurogenus inoculation, the genes associated with phosphate transporter, phosphatase, peroxidase and high-affinity nitrate transporter were upregulated in 31778, whereas AP2-EREBP-transcription factors were detected at significantly higher levels in CCM454. This study provided insights on the molecular mechanisms underlying plant–endophytic fungus symbiosis and low-P stress in maize with low-P-sensitive and -tolerant genotypes. [ABSTRACT FROM AUTHOR]

The scarcity of phosphorus (P) makes improving phosphorus use efficiency a critical issue in crop production. Plant rhizosphere microorganisms play a vital role in increasing phosphorus bioavailability and promoting the level of plant-absorbable P in agroecosystems. In this study, Talaromyces purpurogenus SW-10 strain with efficient organic phosphate-mineralizing ability was isolated from maize rhizosphere soil. SW-10 showed efficient phytate utilization with corresponding soluble P levels of 525.43 mg/L and produced phytase in the liquid medium. The response surface methodology (RSM) analysis showed that glucose as the carbon source and (NH4)2SO4 as the nitrogen source at 28 °C and pH 7.0 promoted higher mineralization of insoluble organic phosphate. When cocultivated with different genotypes of maize seedlings, SW-10 significantly increased the shoot's dry weight by 37.93%, root's dry weight by 31.25%, and the plant height by 13.03% for low-P sensitive inbred line 31778, while no significant change was observed in the low-P tolerance inbred line CCM454. In addition, SW-10 strain significantly increased total P-concentration in the shoots (22.4%~32.9%) and roots (3.10%~9.77%) for both inbred lines. In conclusion, the isolated T. purpurogenus SW-10 strain possesses an efficient organic phosphate-mineralizing ability and maize plant growth-promoting effect, especially for the low-P sensitive genotype that could be exploited for enhancing P availability in agriculture. [ABSTRACT FROM AUTHOR]

In production and operation activities, some enterprises' capacity can not make up for market demand. To meet customer needs, overtime is one of the most common measures taken by enterprises. In this restricted situation, a combination strategy of overtime and subcontracting is introduced to improve the production. When orders occur, the vendor offers a credit time to the buyer, and it is assumed that daily demand is an exponential function of credit time. In this paper, a two-echelon supply chain with overtime and subcontracting under a trade credit policy is studied when limited production capacity exists. The main objective of this paper is to determine the buyer's optimal ordering quantity and the vendor's optimal overtime and subcontracting strategies with an optimal credit period, which minimize the costs of an independent decision model and an integrated model, respectively. Adequate numerical examples and sensitivity analysis are presented to demonstrate the applicability of the proposed framework. The conclusions show that inefficient overtime satisfies low demand under limited production capacity and that the vendor turns to subcontractors when demand grows. [ABSTRACT FROM AUTHOR]

Wheat/soybean rotation is an important double-cropping system in the Huang-Huai-Hai plain of China. Continuous soybean cropping could cause soil quality deterioration and plant growth inhibition. However, the effects of continuous wheat/soybean cropping on soybean rhizosphere microbes remain largely unknown. In this study, we compared the soybean yield and rhizosphere soil microbial community between continuous winter wheat/summer soybean (W/S) with two harvests in one year and winter wheat/summer soybean-winter wheat/summer maize (W/S-W/M) with four harvests in two years. The results showed that the soybean yield in the W/S group significantly (p < 0.05) declined within the first two years. The W/S-W/M showed higher soybean yield and soil fertility index than the W/S group. The sequencing results revealed that cropping rotation had a higher impact on the fungal community than the bacterial community. The W/S group showed 22.08–23.01% higher alpha diversity of the fungal community, but the alpha diversity of the bacterial group did not vary significantly in this group. The fungal community composition in the W/S and W/S-W/M groups differed significantly. In the W/S-W/M group, a higher relative abundance of plant growth-promoting fungi (e.g., Mortierella), nematophagous fungi (e.g., Plectosphaerella), and biological control fungi (e.g., Coniothyrium) was observed. In the W/S group, a higher relative abundance of lignocellulose-degrading fungi (e.g., Trechispora, Myceliophthora, Botryotrichum, and Coniochaeta) and pathogenic fungi (e.g., Pyrenochaetopsis and Cyphellophora) was observed. LEfSe analysis demonstrated that Mortierella, Myceliophthora, and Trechispora could serve as crucial biomarkers. Mortierella was positively associated with available P levels and negatively associated with NO3−-N levels and pH while Trechispora showed the opposite trend. The findings of this study could enhance the current understanding of the mechanisms associated with the continuous wheat/soybean cropping obstacles and ensure the sustainability of agricultural production. [ABSTRACT FROM AUTHOR]