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Pears are an important income source in China, and unreasonable management practices have had a negative impact on the sustainability of pear orchards. However, multi-objective synergistic strategies are unclear on a farmer scale. In this study, we quantified indicators of soil fertility (soil organic matter (SOM)), environmental impact (global warming potentials (GWP)), and economic benefit (ratio of benefit and cost (BCR)) and analysed the synergetic strategies based on survey data from 230 smallholders in the Yangtze River Basin (Shanghai City, Chongqing City, Zhejiang province, and Jiangxi province). The average SOM, GWP, and BCR were 28.9 g kg

BACKGROUND Foliar application of highly concentrated ZnSO4 fertilizer improves Zn biofortification in wheat grains. However, excess ZnSO4 ·7H2 O concentration (≥ 5 g kg-1 , w v-1 ) has been associated with leaf burn and yield loss, necessitating the need for Zn sources with high threshold concentration. Therefore, the aim of this study, based on a 2-year field experiment conducted on wheat cultivated in acidic and alkaline soil, was to identify a suitable Zn formulation with a high Zn concentration or efficient adjuvant to achieve optimal Zn biofortification levels without compromising agronomic performance. RESULTS There was a continued increase in the Zn concentration of wheat grains and a decrease in grain yield with an increase in the concentration of the Zn foliar sprays in both soil types examined. Wheats treated with chelated Zn foliar sprays (ZnGly and ZnEDTA) had less foliar injury compared with those treated with unchelated Zn fertilizers. Furthermore, respective of wheat cultivars and soil types, ZnEDTA applied to wheat at a concentration of 10 g kg-1 achieved the highest grain Zn concentration without negatively affecting the wheat performance. Adjuvant type and concentration caused no significant variation in grain Zn concentration. CONCLUSION Overall, without foliar burn, wheat treated with 10 g kg-1 ZnEDTA foliar spray had the best performance with regards to grain Zn concentration and grain yield, which could have considerable implications for Zn biofortification of wheat grain. This article is protected by copyright. All rights reserved.

To meet the food demand of an increasing population, hybrid rice varieties with high yields were selected, including indica-japonica hybrids. However, information about growth characteristics under...

Biotin is an important enzyme cofactor that plays a key role in all three domains. The classical bifunctional enzyme BioDA in eukaryotes (such as Aspergillus flavus and Arabidopsis thaliana) is involved in the antepenultimate and penultimate steps of biotin biosynthesis. In this study, we identified a A. flavus bifunctional gene bioDA which could complement both Escherichia coli ΔEcbioD and ΔEcbioA mutants. Interestingly, the separated domain of AfBioD and AfBioA could, respectively, fuse with EcBioA and EcBioD well and work together. What is more, we found that BioDA was almost localized to the mitochondria in A. flavus, as shown by N-terminal red fluorescent protein tag fusion. Noteworthy, the subcellular localization of AfBioDA is never affected by common environmental stresses (such as hyperosmotic stress or oxidative stress). The knockout strategy demonstrated that the deletion of AfbioDA gene from the chromosome impaired the biotin de novo synthesis pathway in A. flavus. Importantly, this A. flavus mutant blocked biotin production and decreased its pathogenicity to infect peanuts. Based on the structural comparison, we found that two inhibitors (amiclenomycin and gemcitabine) could be candidates for antifungal drugs. Taken together, our findings identified the bifunctional AfbioDA gene and shed light on biotin biosynthesis in A. flavus.

Plant S deficiency is common, but the role of S-containing amino acids such as cysteine in plant S uptake is unknown. We applied 14C-, 35S-, 13C-, and 15N-labelled cysteine to wheat and oilseed rape rhizospheres and traced the plants’ elemental uptake. Both plants absorbed 0.37–0.81% of intact cysteine after 6 h with no further increase after 24 h. They absorbed 1.6–11.5% 35S and 12.3–7.6% 15N from cysteine after 24 h and utilised SO42− as their main S source (75.5–86.4%). Added and naturally occurring cysteine-S contributed 5.6 and 1.1% of total S uptake by wheat and oilseed rape, respectively. Cysteine and inorganic S derived from cysteine contributed 24.5 and 13.6% of uptake for wheat and oilseed rape, respectively, after 24 h. Oilseed rape absorbed ~10-fold more S from cysteine and SO42− than did wheat. The highest absorption of free cysteine should be in the organic-rich soil patches. Soil microorganisms rapidly decomposed cysteine (t1/2 = 1.37 h), and roots absorbed mineralised inorganic N and S. After 15 min, 11.7–14.3% of the 35S-cysteine was retained in the microbial biomass, while 30.2–36.7% of the SO42− was released, suggesting that rapid microbial S immobilisation occurs after cysteine addition. Plants acquire N and S from cysteine via unidirectional soil-to-root nutrient flow, and cysteine is an important S source for plants.

The application of nitrogen (N) fertilizer as base fertilizer in plastic film mulching cultivation (PFMC) system easily leads to soil N deficiency in the late growth period of rice. The combination...

Nutrient requirements for single-season rice using the quantitative evaluation of the fertility of tropical soils (QUEFTS) model in China have been estimated in a previous study, which involved all the rice varieties, however, it is unclear whether a similar result can be obtained for different rice varieties. In this study, data were collected from field experiments conducted from 2016 to 2019 in Zhejiang Province, China. The dataset was separated into two parts: japonica/indica hybrid rice and japonica rice. To produce 1000 kg of grain, 13.5 kg N, 3.6 kg P, and 20.4 kg K were required in the above-ground plant dry matter for japonica/indica hybrid rice, and the corresponding internal efficiencies (IEs) were 74.0 kg grain per kg N, 279.1 kg grain per kg P, and 49.1 kg grain per kg K. For japonica rice, 17.6 kg N, 4.1 kg P, and 23.0 kg K were required to produce 1000 kg of grain, and the corresponding IEs were 56.8 kg grain per kg N, 244.6 kg grain per kg P, and 43.5 kg grain per kg K. Field validation experiments indicated that the QUEFTS model could be used to estimate nutrient uptake of different rice varieties. We suggest that variety should be taken into consideration when estimating nutrient uptake for rice using the QUEFTS model, which would improve this model.

Agronomic practises, such as fertilisation and crop rotation, affect soil microbial communities and functions. However, limited information is available regarding the relative importance of fertilisation and crop rotation stages in determining the soil microbiome and assembly processes. In addition, insights into the connections between the soil microbiome and enzymatic stoichiometry are scarce. In this study, soil samples were collected from a wheat-rice rotation system that received mineral and organic fertiliser inputs for 6 years to investigate soil microbiome assembly, and the relationship between the soil microbiome and enzymatic stoichiometry. Our results revealed that the crop rotation stage strongly affected the soil microbial community structure, assembly, and enzymatic functions compared to that of the fertilisation regime. Enzymatic stoichiometry results and vector analysis implied that mineral and organic fertilisation could alleviate the microbial N limitation. However, no-manure fertilisation led to microbial P limitation during the wheat stage. The decreases in soil pH mainly drove microbial P limitation due to the acidification induced by the mineral fertilisers. Microbial N/P limitation correlated more strongly with the bacterial assembly than with fungal assembly. Moreover, co-occurrence network analysis showed that ecological relationships between microbial taxa and enzymes were more complex during the wheat stage than that during the rice stage. Microbial nodes linked to acid phosphomonoesterase correlated significantly with the soil pH. Our study highlights the distinct responses of the soil microbiome to fertilisation in different crop-rotation stages, and provides novel insights into connections between microbial assembly and enzymatic stoichiometry.

Aims Soil in tea plantations is characterised by severe acidification and high aluminium and fluorine content. Applying excessive nitrogen (N) is a common strategy in tea plantations. Fungal and bacterial responses to N fertiliser addition in tea plantations, especially their relationship with tea growth, quality, and soil microbiome composition, remain unclear. Methods We performed a field experiment using different N fertiliser application rates for 5 years (2016‒2020) in a tea-producing region of China. Results Application of excessive N (600 kg ha− 1 y− 1) reduced tea yield and quality. High N application rates (360 and 600 kg ha− 1 y− 1) significantly decreased bacterial and fungal diversity and altered the compositions of bacterial and fungal communities (P

Biotin is an important enzyme cofactor that plays a key role in all three domains. The classical bifunctional enzyme BioDA in eukaryotes (such as

Myst family are highly conserved histone acetyltransferases in eukaryotic cells and are known to play crucial roles in various cellular processes, however, acetylation catalyzed by acetyltransferases is unclear in filamentous fungi. Here, we identified two classical nonessential Myst enzymes and analyzed their functions in Aspergillus flavus, which generates aflatoxin B1, one of the most carcinogenic secondary metabolites. MystA and MystB located in nuclei and cytoplasm, and mystA could acetylates H4K16ac, while mystB acetylates H3K14ac, H3K18ac and H3K23ac. Deletion mystA resulted in decreased conidiation, increased sclerotia formation and aflatoxin production. Deletion mystB lead to significant defects in conidiation, sclerotia formation and aflatoxin production. Additionally, double-knockout mutant (ΔmystA/mystB) display a stronger and similar defect to ΔmystB mutant, indicating that mystB plays major role in regulating development and aflatoxin production. Both mystA and mystB play important role in crop colonization. Moreover, catalytic domain MOZ and the catalytic site E199/E243 were important for the acetyltransferase function of Myst. Notably, chromatin immunoprecipitation results indicated that mystB participated in oxidative detoxification by regulating the acetylation level of H3K14, and further regulated nsdD to affect sclerotia formation and aflatoxin production. This study provides new evidences to discover the biological functions of histone acetyltransferase in A. flavus. This article is protected by copyright. All rights reserved.

Nano zero-valent iron (nZVI) is a promising remediation material for Cd-contaminated soil, but questions remain regarding the effects of nZVI-induced Fe oxides on Cd availability with different soil types and moisture conditions. To identify the changes in Cd availability and Fe mineral phases resulting from the application of nZVI, three types of Cd-spiked soils with 0.1% nZVI amendment were incubated under different moisture conditions with water-holding capacities (WHCs) of 30%, 60%, and 180%. The availability of Cd was significantly decreased in yellow and black soils amended with nZVI, with fewer changes being observed in cinnamon soil. The limited effect of nZVI on Cd stabilization was due to the extremely low content of poorly crystalline Fe phases in cinnamon soil. The Cd stabilization efficiency of nZVI was higher in the flooding soils (180% WHC) than in the non-flooding yellow and black soils (30% and 60% WHC, respectively). Moreover, the addition of nZVI promoted the formation of less-available forms of Cd (Fe-oxide-bound Cd in yellow soil and Fe-oxide-bound and organic-material-bound Cd in black soil) under the flooding condition. The decrease in extractable Cd was strongly related to the increase in poorly crystalline Fe(Ⅱ) mineral phases among the three soils and various soil moisture contents. Although 0.1% nZVI amendment induced the dissolution of Mn oxides, it did not hinder the Cd stabilization in the three soils. Overall, this study indicates that increased amounts of poorly crystalline Fe(Ⅱ) compounds due to nZVI amendment play a critical role in the stabilization of Cd in soils.

BACKGROUND In neutral or alkaline soils, iron (Fe) easily forms insoluble complexes, which makes it difficult for plants to utilize Fe in the soil for nutrition. Polyester sulfur-coated urea (PSCU) is a novel controlled-release fertilizer widely used in China and some foreign countries, and it has been proven that sulfur film from controlled-release fertilizers can significantly improve the activation of Fe and other elements in the soil. However, few studies have focused on the effects of PSCU application on Fe accumulation in rice grain in alkaline soils. RESULTS Both our field and pot experiments proved that PSCU application could significantly improve rice grain yield and Fe concentration in brown rice in alkaline soil. This effect differs with different types of alkaline soils (i.e. medium-saline, sandy soil and/or silt soil). PSCU is released slowly, and the release rate is different in different alkaline soils. Rice shoot nitrogen (N) uptake was significantly enhanced with PSCU application. CONCLUSION The results suggested that PSCU application in alkaline soils could significantly enhance brown rice Fe concentration and production. This effect differed with different kinds of alkaline soils. The study identified some efficient fertilizers to improve the Fe status in alkaline soils. © 2021 Society of Chemical Industry.

Histone deacetylases (HDACs) always function as corepressors and sometimes as coactivators in the regulation of fungal development and secondary metabolite production. However, the mechanism through which HDACs play positive roles in secondary metabolite production is still unknown. Here, classical HDAC enzymes were identified and analyzed in Aspergillus flavus, a fungus that produces one of the most carcinogenic secondary metabolites, aflatoxin B1 (AFB1). Characterization of the HDACs revealed that a class I family HDAC, HosA, played crucial roles in growth, reproduction, the oxidative stress response, AFB1 biosynthesis, and pathogenicity. To a lesser extent, a class II family HDAC, HdaA, was also involved in sclerotia formation and AFB1 biosynthesis. An in vitro analysis of HosA revealed that its HDAC activity was considerably diminished at nanomolar concentrations of trichostatin A. Notably, chromatin immunoprecipitation experiments indicated that HosA bound directly to AFB1 biosynthesis cluster genes to regulate their expression. Finally, we found that a transcriptional regulator, SinA, interacts with HosA to regulate fungal development and AFB1 biosynthesis. Overall, our results reveal a novel mechanism by which classical HDACs mediate the induction of secondary metabolite genes in fungi.

In Aspergillus, the cyclic adenosine monophosphate (cAMP) signaling modulates asexual development and mycotoxin biosynthesis. Here, we characterize the cyclase-associated protein Cap in the pathogenic fungus Aspergillus flauvs. The cap disruption mutant exhibited dramatic reduction in hyphal growth, conidiation, and spore germination, while an enhanced production of the sclerotia was observed in this mutant. Importantly, the cap gene was found to be important for mycotoxin biosynthesis and virulence. The domain deletion study demonstrated that each domain played an important role for the Cap protein in regulating cAMP/protein kinase A (PKA) signaling, while only P1 and CARP domains were essential for the full function of Cap. The phosphorylation of Cap at S35 was identified in A. flavus, which was found to play a negligible role for the function of Cap. Overall, our results indicated that Cap with multiple domains engages in mycotoxin production and fungal pathogenicity, which could be designed as potential control targets for preventing this fungal pathogen.

Controlled-release, slow-release and stabilized nitrogen (N) fertilizers can potentially increase crop production and reduce N losses. However, information is limited regarding their medium- and long-term effects on rice productivity and soil chemical properties. Therefore, we investigated the effects of these three types of N fertilizer on rice grain yield, apparent N recovery efficiency (ANR), and soil chemical properties in a double cropped rice system over a 7-year period in Zhejiang Province, China. This study examined six N treatments: no N fertilizer (CK), split application of prilled urea (Urea), a single basal application of polymer-coated sulfur-coated urea (PSCU, formed by coating SCU with a polymer coating), urea with a nitrification inhibitor (UNI), urea formaldehyde (UF), and a mixture of PSCU and prilled urea (Mix). The effect of N treatment varied over the 7 years, but annual grain yields of double cropped rice with UNI, UF, and Mix were significantly higher than with Urea in 6/7, 4/7 and 3/7 years, respectively, and similar to yield with Urea in the other years. Performance of PSCU was variable, with significantly higher yields than Urea in 3/7 years, but lower yields in 2/7 years. Compared to Urea, the UNI treatment increased the grain yield and ANR of early rice by averages of 9.2 and 24%, respectively, and increased the grain yield and ANR of late rice by averages of 8.6 and 22%, respectively. Total N in the topsoil (0–20 cm) of the CK declined gradually during years 2-4. At the end of each of years 4–7, total soil N in all N fertilized treatments exceeded that in the CK. After 7 years, the five N fertilized treatments had 8–17% higher topsoil total N than the initial value, with no significant difference between these treatments. Available P increased over time in all treatments, with higher values in the CK than the five N fertilized treatments after the first year. After 7 years, available P was 387–529% higher in the N fertilized treatments than the initial value, and with no significant differences between these treatments. However, available K declined considerably in the five N fertilizer treatments during the first four years, but then steadily increased during the next three years when the application rate was increased from 120 to 200 kg K ha−1. Soil pH declined over the seven years, more so in PSCU and Mix when pH declined from 5.2 to 4.5, compared with declines to 4.7–4.9 in the other treatments. Although fertilizer for the UNI treatment cost $ 29 ha−1 more than for the Urea treatment, the higher yield/revenue and lower fertilization labor cost of UNI led to increases in net profit of $ 326 and 329 ha−1 year−1 in early and late rice, respectively. Overall, application of UNI was the superior alternative to prilled urea in the double rice cropping system because of consistently higher yield and profitability, while maintaining soil fertility at similar levels to the other N fertilizer options.

Non-flooding plastic film mulching (PM) cultivation is a promising water-saving technology for rice cultivation. However, because the N fertilizer can only be applied before transplanting due to technical difficulties with later applications, it results in excessive vegetative growth and potential N shortages during the reproductive stages, which may limit grain yield potential. The use of polymer-coated urea (PCU), a slow release N fertilizer, has become one of the best management practices for increasing crop yield and improving N recovery efficiency in traditional flooded rice cultivation (TF), but has not been tested in PM cultivation. The objective of the eight-year (2008–2015) field experiment in the present study was to compare the effects of PCU with a conventional prilled urea fertilizer (PU) and a control (no N fertilizer applied; CK) on grain yield, N recovery efficiency, yield components, and soil nutrients under PM and TF cultivation systems. Within fertilizer treatment, plant N uptake and N recovery efficiency were almost always significantly higher in the PM than the TF cultivation treatments. PCU application significantly increased these parameters in both cultivation systems, but usually by significantly more with PM cultivation. Compared to the PU treatment, PCU significantly increased rice grain yield in both cultivation systems every year (by means of 11% and 15% in the TF and PM, respectively), except for TF in the first year. Within fertilizer treatment, yields of PM and TF were similar. In comparison with PU, the use of PCU had no effect on soil organic matter or alkali-hydrolyzable N. However, PM cultivation decreased these parameters. In conclusion, PCU application increased the N recovery efficiency and N availability in both cultivation systems during the reproductive stages of rice, and thus improved rice grain yield. We demonstrated that the application of PCU is a practical N fertilizer management technique that improves rice grain yield and N recovery efficiency, and is an effective solution to fertilization challenges in PM rice cultivation systems.

Foliar sprays of iron (Fe) and zinc (Zn) fertilizers are effective in improving Fe and Zn concentrations in sweet potato. The objective of this experiment was to examine the effects of foliar ferti...