Scientia Agricultura Sinica

Distribution of Soybean Cyst Nematode Resistance Allele Rhg1 and Rhg4 in Huang-Huai Soybean Varieties

LIAN Yun,LI HaiChao,LI JinYing,WANG JinShe,WEI He,LEI ChenFang,WU YongKang,LU WeiGuo

Scientia Agricultura Sinica. 2019, 52(15): 2559-2566. doi:10.3864/j.issn.0578-1752.2019.15.001

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【Objective】The disease caused by soybean cyst nematode (SCN, Heterodera glycines) is an important worldwide soybean disease. Planting SCN-resistant cultivars has formed the primary basis for controlling SCN. SCN spread widely and infect heavily in the Huang-Huai Valleys almost wherever soybean is grown. This study genotyped the SCN resistance alleles distributed in Huang-Huai soybean varieties and the results will provide scientific basis for guiding the rational and effective utilization of resistant varieties. 【Method】In this study, four KASP developed from Rhg1 and Rhg4 loci were selected. The validity of selected KASP marker were verified by genotyping 16 known resistant varieties such as ZDD2315, Zhonghuang 57 and ShanxiXiaoheidou together with 3 known susceptible varieties such as Willams and Lee. Then, 170 soybean varieties cultivated from Huang-Huai Valleys, such as Yudou series, Shangdou series and Zhoudou series were genotyped. The resistance level of the varieties harboring more than two resistance alleles were tested by inoculating race 2, race 4, race 5 and new race X12 in greenhouse, respectively. These races are distributed widely Huang Huai Valley. 【Result】 There were 5 and 6 varieties harboring Rhg1-2(CC) and Rhg1-5(CC) resistance alleles, respectively. There were 6 and 7 varieties harboring Rhg4-3(TT) and Rhg4-5(CC) resistance alleles, respectively. There were 6 varieties names Kaidou 4, Shangdou 1201, Lu 0305-2, Luo 4903, Weidou12 and Weidou 91861 which harboring 2 or more resistance alleles and accounted 3.53% in tested varieties. By inoculation, the 6 varieties showed different sensitive degree to race 2, race 4 or race X12. Lu 0305-2 and Weidou 91861 showed high resistance to race 5 with FI (10.00 ± 0.48) and (7.00 ± 0.63), respectively. Shangdou 1201 showed resistance to race 5 with FI (26.20 ± 0.91). Kaidou 4, Luo 4903 and Weidou12 showed sensitive or high sensitive to race 5 with FI (35.00 ± 2.48), (64.80 ± 3.91) and (58.20 ± 2.19), respectively. 【Conclusion】The results showed that SCN-resistant alleles in Rhg1 or Rhg4 were rare in the released Huang Huai Valleys varieties. More attention should be paid to introduce SCN-resistant alleles in cultivating varieties. Combined with the dominant race of SCN distributed in Huang Huai Valley, the varieties that resistant to multiple races should be given priority in breeding. The four KASP used in this study could be used to phenotype and screen the resistant sources.

Development and Characterization of Whole Genome SSR in Tetraploid Wild Peanut (Arachis monticola)

WANG YuLong, HUANG BingYan, WANG SiYu, DU Pei, QI FeiYan, FANG YuanJin, SUN ZiQi, ZHENG Zheng, DONG WenZhao, ZHANG XinYou

Scientia Agricultura Sinica. 2019, 52(15): 2567-2580. doi:10.3864/j.issn.0578-1752.2019.15.002

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【Objective】We aimed to identify simple sequence repeat (SSR) loci throughout the genome of tetraploid wild peanut Arachis monticola (AABB, 2n = 4x = 40), to identify their distribution characteristics, and to develop and validate SSR primers. These markers have potential uses in genetic evolution analyses and in the development of molecular markers for important traits in peanut.【Method】Using the bioinformatics software MISA, we searched for SSR loci in the whole genome sequence of A. monticola, which was downloaded from the GigaScience database of the BGI. One hundred SSR loci were randomly selected and primers were designed and synthesized. The primers were used to amplify products from four different Arachis genomes, and the products were analyzed by polyacrylamide gel electrophoresis (PAGE).【Result】 A total of 676 878 SSRs were found in the genome of tetraploid wild peanut A. monticola in 5 127 scaffolds (average, one SSR per 3.8 kb). The SSRs ranged from single nucleotides to hexanucleotides. Single nucleotide SSRs were significantly more abundant than hexanucleotide SSRs. Single, double, and triple nucleotide SSRs were predominant, accounting for 94.28% of all the SSRs. Single nucleotide SSRs accounted for the largest proportion of total SSRs (46.71%) and showed the highest density. Hexanucleotide SSRs accounted for the smallest proportion and showed the sparsest density. Most SSRs were located in intergenic regions, and most of the SSRs in gene sequences were located in introns. A total of 395 different repeat motifs were identified in the whole genome, of which 342 were in the A-subgenome and 356 were in the B-subgenome. The most abundant repeat motif was A/T. The most abundant repeat motifs for SSRs with 1-6 nucleotides were A/T, AT/AT, AAT/ATT, AAAT/ATTT, AAAAT/ATTTT, and AAAAAT/ATTTTT, respectively. There were less than 50 of each type of SSR repeat motif, but the number of each type of SSR motif varied greatly. The number of each type of SSRs repeat motif decreased with increasing number of nucleotides in the motif. Chromosome B03 had the most SSRs, and chromosome A08 showed the highest density of SSRs. We designed 192 303 pairs of SSR primers, and the detection rate of single-locus SSR markers was 50.35%. The distribution of SSR markers in the genome was dense at both ends and sparse in the middle. Among the 100 synthesized primer pairs, 90 pairs amplified stable and clear bands from A. monticola genomic DNA. The bands amplified from four different peanut genomic DNAs showed different characteristics. 【Conclusion】The A. monticola genome was rich in SSRs ranging from single nucleotides to hexanucleotides. Single nucleotide repeats were the most abundant and densely distributed, and hexanucleotides showed the lowest frequency and the sparsest distribution. There was no strict correlation between the frequency of different repeats and the repeat type. The A-subgenome and B-subgenome had their own specific SSRs. The AT-enriched repeat motifs were the most abundant, while GC-enriched repeat motifs showed much lower frequencies. The number of SSRs with the same type of repeat motif decreased with increasing numbers of nucleotides in the motif. Compared with the genomes of the two diploid wild species, the tetraploid genome of A. monticola had more SSRs, a higher density of SSRs, and a different SSR distribution pattern. Preliminary validation analyses showed that the SSR primers designed in this study shared certain universal properties among four Arachis genomes.

Effects of Artificial Warming from Late-Winter to Early-Spring on Photosynthesis and Flag Leaf Senescence of Winter Wheat

YAN Peng, SUN XiaoNuo, DU Xiong, GAO Zhen, BIAN DaHong

Scientia Agricultura Sinica. 2019, 52(15): 2581-2592. doi:10.3864/j.issn.0578-1752.2019.15.003

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【Objective】 In view of the contradiction between the optimum temperature required for the growth and development of winter wheat and the actual temperature provided in the environment in the north of North China Plain, we attempted to artificially increase the temperature from the end of January to the end of March through plastic-film greenhouse and study the effect of temperature on photosynthesis and flag leaf senescence of winter wheat, in order to provide theoretical and methodological basis for delaying wheat senescence by regulating temperature and tapping the yield potential of winter wheat in North China Plain.【Method】 Field experiments were conducted at Shenzhou Dry-Farming and Water-Saving Agricultural Test Station of Hebei Academy of Agricultural and Forestry Sciences in two consecutive growing seasons from 2015 to 2017. Using ‘Hengguan 35’ as experimental material, greenhouses were constructed in late winter and early spring. Four treatments were set up, i.e., cover 2 layers of plastic film (M2E, January 25-March 25), 2 layers of plastic film (M2L, February 5-March 25), 1 layer of plastic film (M1, February 20-March 25), and conventional production control (CK). Temperature and wheat production and development time were regulated by covering porous and non-porous plastic film and its covering time, which resulted in different growth and development processes in the same date, and the same growth process in different dates and temperatures. During the experiment, the beginning time of each growth period was recorded, and the indexes of photosynthetic characteristics, senescence-related enzymes activity, yield, and water use efficiency were measured. 【Result】 The treated wheat was in a relatively higher temperature in pre-jointing stage and lower temperature after jointing, it promoted the wheat to grow earlier and prolong its developing period. The winter wheat in M2E treatment was 7-8 days earlier than the control in flowering and 3-4 days earlier in ripening; At grain filling stage, the net photosynthetic rate of flag leaf increased by 24.9%, the relative content of chlorophyll, superoxide dismutase (SOD), catalase (CAT) and peroxidase (POD) increased by 13.3%, 17%, 17% and 14.2%, respectively, while the content of malondialdehyde (MDA) decreased by 22.7%. Flag leaf area increased by 27% at flowering, grain yield increased by 22.8% at harvest and water use efficiency increased by 15.2%. With the delay of warming time and the shortening of covering time, the difference of the above indexes was smaller and smaller, so that there was no significant difference between M1 treatment and CK treatment. 【Conclusion】 Warming in late-winter and early-spring not only significantly prolonged the filling time of wheat, but also maintained higher photosynthesis of flag leaves and delayed senescence of flag leaves, which provided more material basis for grain filling, and promoted the efficient use of water at the same time of obtaining high yield. Increasing temperature in late winter and early spring could be suitable for rational allocation of heat resources and growth and development needs of winter wheat in the north of North China Plain. At the same time, it could not only alleviate the harm of late spring cold on wheat, but also avoid the influence of dry-hot wind on wheat in later growth stage.

Effects of Hyperspectral Prediction on Leaf Nitrogen Content and the Grain Protein Content of Broomcorn Millet

WANG JunJie,CHEN Ling,WANG HaiGang,CAO XiaoNing,LIU SiChen,TIAN Xiang,QIN HuiBin,QIAO ZhiJun

Scientia Agricultura Sinica. 2019, 52(15): 2593-2603. doi:10.3864/j.issn.0578-1752.2019.15.004

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【Objective】The objective of the study was to explore the best spectral prediction model of protein content in the grain of broomcorn millet based on leaf nitrogen content, which provided theoretical basis for the management and regulation of high-quality production of broomcorn millet.【Method】Using experimental data and spectral data of nitrogen application in 2017 and 2018, the predicting models on grain protein content were constructed based on hyperspectral by linking the spectral models and grain protein content with leaf nitrogen content as intersection in broomcorn millet. 【Result】The support vector machine (SVM) which constructed monitoring model of leaf nitrogen content at full growth period was superior to stepwise multiple linear regression (SMLR) and partial least square (PLS), and R-SVM was superior to 1ST-SVM, the R ² of calibration set and validation set were 0.928 and 0.924, respectively, RMSE were 0.19 and 0.12, respectively, and RPD were 3.71 and 6.07, respectively. Leaf nitrogen content and grain protein content at heading, filling and maturing stages were significantly positively correlated, and their correlation coefficients were 0.48, 0.66 and 0.73, respectively. The R-SVM at filling stage could monitor the grain protein content accurately of broomcorn millet.【Conclusion】Establishing monitoring model of R-SVM based on grain protein content in broomcorn millet at filling stage, which could help to guide the field management, adjustment of planting structure and grain quality grading, and to provide technical basis for hyperspectral technology in the development of high quality and high yield cultivation and precision agriculture.

Effects of Ceriporia lacerata on Gummy Stem Blight Control, Growth Promotion and Yield Increase of Cucumbers

BAI RuXia,ZENG HuiWen,FAN Qian,YIN Jie,SUI ZongMing,YUAN Ling

Scientia Agricultura Sinica. 2019, 52(15): 2604-2615. doi:10.3864/j.issn.0578-1752.2019.15.005

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【Objective】The objective of this study is to clarify the effects of Ceriporia lacerata on plant disease control and growth promotion, and to provide a basis for reducing the application of chemical pesticides and fertilizers.【Method】A new self-isolated C. lacerata (fungal strain HG2011) was grown in Bonnet liquid medium and mixture made of vermiculite, maize powder, and rice husk, respectively, to produce culture broth (CLB) and solid inoculant (CLA). CLB and CLA were prepared and conduced to evaluate the effect of C. lacerata on the antagonistic activity against Mycosphaerella melonis, control of gummy stem blight, vegetative growth of cucumber seedlings, yield of cucumbers, soil enzyme activity, and quality of cucumbers with the method of antagonistic assay, confront culture, greenhouse pot experiments, and field experiments, respectively.【Result】In the antagonistic assay, the inhibition rate of 50% CLB against M. melonis was 32.39% in agar medium at the 6th day, which was similar to that of thiophanate methyl (TM). In the confront culture assay, C. lacerata HG2011 inhibited the growth of M. melonis, this antagonistic fungus could cover M. melonis colonies and make the hyphae deformed, shrunken and disappeared. In greenhouse pot experiments, the incidence of pathogen inoculation (PI) treatment was 36.67% and the disease index was 38.40. Compared with PI, CLB could significantly reduce the incidence and disease index of gummy stem blight, and the relative control efficacy was 79.69%, which was also similar to that of TM (75.57%). Compared with single conventional fertilization (CF), the application of CLB could promote the seedling growth, increase the biomass, root activity and chlorophyll content in leaves by 5.87%-21.45%, 36.50%-38.83% and 10.54%-19.80%, respectively. The nutrient uptake by cucumber seedlings increased by 45.24%-69.05% (nitrogen), 20.51%-43.59% (phosphorus), and 19.88%-38.51% (potassium), respectively. The activities of urease, acid phosphatase, catalase, cellulase, dehydrogenase, and protease increased by 8.73%-35.84%, 7.55%-10.74%, 25.32%-26.49%, 186.21%-279.23%, 47.99%-76.51% and 49.00%-100.00%. The effect of high dose (150 mL) CLB treatment was better than that of low dose (75 mL) CLB treatment. In field experiments, application of CLA on the basis of CF (CF+CLA₁₀) increased fruit quantity of plant by 13.61%, yield by 13.87%, and free amino acids content by 71.54%. Application of CLA on the basis of reducing 25% CF (75% CF+CLA₁₀) increased fruit quantity of plant by 11.51%, yield by 11.71%, and free amino acids content by 54.37%. In addition, compared with CF, 75% CF+CLA₁₀ significantly decreased nitrate content by 14.93%. 【Conclusion】 C. lacerata HG2011 strain can inhibit hyphal growth of M. melonis. Spraying CLB can control gummy stem blight, reduce the incidence and disease index, and improve the control efficacy. Pot application of CLB can increase the activity of soil enzyme, promote the absorption of nutrients by cucumber seedlings, and make the healthy growth of cucumber. Field application of CLA can increase the yield of cucumber and the content of free amino acids in fruits, reduce the content of nitrate content and improve the quality, which is beneficial to reduce application and increase efficiency of chemical fertilizer. C. lacerata HG2011 strain can decompose lignin and cellulose, and grow rapidly in crop straw. Composting with this biological agent can both prevent disease and promote growth.

Binding Characterization of Odorant Binding Protein OBP56h in Drosophila suzukii with Small Molecular Compounds

LI Du, NIU ChangYing, LI FengQi, LUO Chen

Scientia Agricultura Sinica. 2019, 52(15): 2616-2623. doi:10.3864/j.issn.0578-1752.2019.15.006

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【Objective】The objective of this study is to clone the odorant binding protein 56h (OBP56h) gene from Drosophila suzukii, get the recombinant DsuzOBP56h protein, and characterize the binding profiles of DsuzOBP56h with some small molecular compounds.【Method】By means of specific primer, reverse transcription PCR (RT-PCR) was used to clone the full-length ORF of DsuzOBP56h. The sequences of insect OBPs with high similarity were downloaded from NCBI database for sequence alignment and analysis. Using NdeⅠand XhoⅠas restriction sites, OBP56h was ligated into pET-30a (+) prokaryotic expression vector, and transformed into Escherichia coli BL21 (DE3). IPTG was applied to induce the expression of recombinant DsuzOBP56h protein. The bacterial solution was collected and the protein was obtained through breaking cells by ultrasound, and then the protein was purified by the method of Ni-NTA resin. The purified protein was dialyzed by Tris-HCl and the concentration was determined by the method of BCA. The protein was diluted with 50 mmol·L ^-1 Tris-HCl (pH 7.4) to a final concentration of 2 μmol·L ^-1, and the ligand was diluted with chromatography-grade methanol to a final concentration of 1 mmol·L ^-1. The binding characterization of DsuzOBP56h with 18 small molecular compounds was investigated using bis-ANS as fluorescence probe. 【Result】 The full-length ORF of OBP56h in D. suzukii was amplified, which is 405 bp in total, including 19 amino acids of signal peptide in the N-terminal. It has 6 conserved cysteine sites, which is consistent with the typical characteristics of OBPs, and has the closest evolutionary relationship with D. melanogaster OBP56h. OBP56h was successfully inserted into pET-30a (+) and expressed at 1 mmol·L ^-1 IPTG and 28℃, then purified by the method of Ni-NTA resin. In the competitive fluorescence assay, the dissociation constant K_bis-ANS was 0.9568 μmol·L ^-1, indicating that bis-ANS is suitable to be a reporter of competitive fluorescence binding assay. Among 18 ligands, the binding affinity of bitter tastants berberine chloride and coumarin with DsuzOBP56h was strong, and the dissociation constant is 12.16 and 17.93 μmol·L ^-1, respectively. The dissociation constant of naringenin with DsuzOBP56h is 25.32 μmol·L ^-1. A volatile odorant β-cyclocitral, which is attractive to D. suzukii produced by strawberry leaves, can also bind to DsuzOBP56h, with the dissociation constant of 31.37 μmol·L ^-1.【Conclusion】The OBP56h in D. suzukii can bind with a variety of bitter tastants and volatile odors from plants, indicating that OBP56h may be involved in the gustatory and olfactory recognition of food in D. suzukii. The results can provide a theoretical basis for understanding the feeding behavior of D. suzukii, and provide a new idea for the ecological prevention and control of D. suzukii.

Effect of Petroleum Ether Extract from Solidago canadensis on Liver of Pomacea canaliculata

LI ShuaiLan,SHEN Xiao,ZOU ZhengRong

Scientia Agricultura Sinica. 2019, 52(15): 2624-2635. doi:10.3864/j.issn.0578-1752.2019.15.007

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【Objective】 On the basis of previous studies, the effect of petroleum ether extract of Solidago canadensis (PEEE) on the liver of Pomacea canaliculata was discussed in depth to provide a basis for further effective control the harm of P. canaliculata to agricultural production and realizing the resource utilization of the malignant alien invasive plant S. canadensis. 【Method】Chlorinated tap water was used as the control group, and PEEE suspensions of 0.11, 0.18 and 0.29 mg?mL ^-1 were used as the experimental groups. In each group, 10 adult P. canaliculata of the same size and vigor were randomly placed, and the beaker was sealed with a layer of gauze and rubber band to prevent the P. canaliculata from escaping. At room temperature (23-27℃), the treatment was carried out for 48 h with 3 repetitions in each group. After 48 h, the P. canaliculata treated with dechlorinated tap water, 0.11, 0.18 and 0.29 mg?mL ^-1 were randomly selected, the shells of P. canaliculata were broken and the liver was taken out, and the ultrastructure of liver tissue was observed by scanning electron microscopy and transmission electron microscopy. The liver tissue of P. canaliculata treated with 0.29 mg?mL ^-1 was lyophilized for metabonomics study. 【Result】The results of scanning electron microscopy showed that the liver surface of P. canaliculata was damaged after soaking for 48 h with different concentrations of PEEE, and the degree of damage was positively related to the concentration of PEEE treatment solution. High concentrations of PEEE could cause liver atrophy and loss of elasticity, wrinkle bulge erosion, body surface damage, flocs and loose texture. The results of transmission electron microscopy showed that the liver cells of P. canaliculata were damaged obviously after soaking for 48 h with different concentrations of PEEE. The number of rough endoplasmic reticulum and mitochondria in liver cells of P. canaliculata decreased with high concentrations of PEEE, and the rough endoplasmic reticulum appeared swelling, breaking and degranulation. Mitochondria showed swelling and irregular shape. The results of metabonomic experiments showed that after PEEE treatment, the content of 60 metabolites in the liver of P. canaliculata changed, and several metabolic pathways were affected. The two pathways with the highest enrichment were glycosphingolipid metabolism and palmitoyl-CoA entering mitochondrial matrix pathway. 【Conclusion】PEEE of S. canadensis has great damage and destruction to the liver cells of P. canaliculata, so it has strong molluscicidal activity and is expected to be developed into a new natural molluscicidal drug with great potential development and application value.

Effects of Long-Term Fertilization on Mineralization of Soil Organic Carbon in Red Paddy Soil

Lü ZhenZhen,LIU XiuMei,ZHONG JinFeng,LAN XianJin,HOU HongQian,JI JianHua,FENG ZhaoBin,LIU YiRen

Scientia Agricultura Sinica. 2019, 52(15): 2636-2645. doi:10.3864/j.issn.0578-1752.2019.15.008

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【Objective】Mineralization of soil organic carbon is an essential process of biochemistry in soils, which is closely related to release of soil nutrients, maintenance of soil quality, and greenhouse effect. Revealing the characteristics of soil organic carbon sequestration and mineralization in rice field ecosystem under long-term fertilization are aimed at correctly evaluating the impact of fertilization on global climate change. 【Method】Based on the 33-year long-term stationary experiment, systematic study of soil organic carbon accumulation and mineralization dynamics of red soil double-rice cropping field in red paddy soil was carried out in this paper. Five fertilization treatments were selected form the long-term stationary experiment which began in 1984, including CK (no fertilizer), NPK (application of chemical), 70F+30M (70% NPK plus 30% organic fertilizer), 50F+50M (50% NPK plus 50% organic fertilizer) and 30F+70M (30% NPK plus 70% organic fertilizer). Soil samples from tillage layer (0-20 cm) were collected before early rice planting in 2017. The amount and rate of CO₂-C released by soil carbon mineralization were determined by incubation method. First-order kinetic model was used to calculate potential mineralization (C₀), easily mineralizing organic carbon (C₁) and turnover rates. 【Result】 All the long-term fertilization treatments increased total organic carbon in the 0-20 cm depth of soil. The content of total organic carbon under NPK treatment was significantly higher than that under CK treatment, 27.32% higher than that under CK treatment. Chemical fertilizer combined with organic fertilizer treatments were all higher than that under NPK treatment (P<0.05), which was 31.31% higher than that under NPK treatment on average. The effects of treatments of 50F+50M and 30F+70M were more obvious. The incubation results showed that mineralization rates of soil organic carbon in all the treatments reached the peak value on the first day and the differences were significant, and the order was: 50F+50M>30F+70M>70F+30M>NPK>CK, then they all decreased and stabilized after 11 days. The order of soil organic carbon mineralization rate after stabilization was: 30F+70M>50F+50M>70F+30M>NPK≈CK. During the whole incubation process, the relation between SOC mineralization rate and incubation days followed the logarithm law. After 35 days incubation, compared with CK, NPK treatment did not significantly change soil organic carbon accumulation mineralization (P>0.05). The cumulative mineralized SOC under 70F + 30M, 50F + 50M and 30F + 70M treatments were significantly higher than that under NPK (P<0.05), with increased 50.99%, 70.85% and 86.39%, respectively. The cumulative mineralization rate of soil organic carbon (the ratio of cumulative mineralization to total organic carbon) under all treatments varied from 3% to 4%, and 30F+70M was significantly higher than NPK (P<0.05). The potential mineralizable SOC in soil were enhanced in varying degrees by adding fertilizers, among which 30F+70M was the highest with 1.19 times higher than NPK. Fertilization did not cause significant changes in turnover rate and half turnover period of SOC. C₀, C₁, cumulative mineralization and cumulative mineralization rate were significantly affected by soil carbon and input carbon content, and showed a positive correlation. C₀ / soil organic carbon was positively correlated with input carbon content (P<0.05), and the rotation rate constant (k) of soil organic carbon was not significantly correlated with soil organic carbon and input carbon. 【Conclusion】 In summary, long-term chemical fertilizer combined with organic fertilizer increased mineralization rate and the accumulation of SOC in red paddy soils, but not significantly changed the mineralized SOC to SOC ratio. This was very useful for nutrient supply and carbon sequestration of red paddy soils.

Effects of Wheat Seeding Rate with Nitrogen Fertilizer Application Reduction on Soil Microbial Biomass Carbon, Nitrogen and Enzyme Activities in Fluvo-Aquic Soil in Huang-Huai Plain

SHI Ke, DONG ShiGang, SHEN FengMin, LONG Qian, JIANG GuiYing, LIU Fang, LIU ShiLiang

Scientia Agricultura Sinica. 2019, 52(15): 2646-2663. doi:10.3864/j.issn.0578-1752.2019.15.009

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【Objective】 The effects of wheat sowing rate and nitrogen fertilizer interaction on soil microbial biomass carbon/ nitrogen (SMBC/N) and enzyme activities in the Huang-Huai Plain of China was studied, aimed to select the optimum management in this area. 【Method】 Field experiment was conducted, and four treatments were set as: (1) conventional seeding + conventional nitrogen fertilizer (CK); (2) 30% additional seeding + conventional nitrogen application (T1); (3) 30% additional seeding + 20% nitrogen reduction (T2); (4) conventional seeding + 20% nitrogen reduction (T3). The soil organic carbon (SOC), total nitrogen (TN), soil microbial biomass carbon (SMBC), soil microbial biomass nitrogen (SMBN), and soil enzyme activities were measured and analyzed in different soil depths during the three crop seasons in 2016-2018. 【Result】 Generally, all the indexes decreased with soil depth. The SMBC was significantly higher under conventional nitrogen (N) treatments (i.e. CK and T1) than that under nitrogen reduction treatments (i.e. T2 and T3) in 0-20 cm in wheat and maize season 2017 and 0-30 cm in wheat season 2018, and the highest one was 170.89 mg?kg ^-1. The dynamics of SMBN was similar as SMBC, which was significantly higher under conventional N treatments than that under N reduction treatments during the all the crop seasons, and with the highest value as 57.24 mg?kg ^-1 under CK treatment. The differences of SOC content among treatments were focused on 0-20 cm during the first and second seasons, and 10-30 cm during the third season. Therein, the SOC content under N reduction treatments was significantly higher than that under conventional N treatments, with the highest one as 12.85 g?kg ^-1 under T3. The TN content under all the treatments was no different in wheat season 2017, which was significantly higher under CK treatment than that under the others in 0-20 cm in maize season 2017 and wheat season 2018. The C/N was no obviously trend in wheat season 2017, while it was significantly higher under N reduction treatments in 0-20 cm during maize season 2017 and wheat season 2018. The SMBC/SOC under all treatments ranged from 0.5% to 2.5%. And it was higher under conventional N treatments than that under N reduction treatments, except which in 10-20 cm during wheat season 2017. The SMBN/TN under all treatments ranged from 2% to 6%. The SMBC/SMBN under all treatments was below 5:1. The SMBN/TN was higher under conventional N treatments than that under N reduction treatments, except which in 10-20 cm during wheat season 2017 and 0-30 cm during wheat season 2018. The SMBC/SMBN under T1 treatment was higher in 2017 wheat season. The urease activity under sowing rate increase treatment (i.e. T1 and T2) was higher in wheat season 2018. The invertase activity in 10-30 cm during maize season 2017 and neutral phosphatase activity in 0-30 cm during wheat season under N reduction treatments was higher than that under conventional treatments. The wheat yield and the aboveground N accumulation was higher under N reduction treatments in wheat season 2018, with the highest value as 6 822.27 kg?hm ^-2and 322.30 kg?hm ^-2, respectively, under T3 treatment.【Conclusion】 Generally, in the Huang-Huai Plain, under the nitrogen reduction, the soil microbial biomass and TN content were decreased, while the soil enzyme activities and aboveground N accumulation was increased. Meanwhile, the wheat yield was increased or maintained. Therein, the treatment with conventional seeding + 20% nitrogen reduction was suggested as the optimum practice in this study.

Effects of Rapeseed Green Manure on Soil Fertility and Bacterial Community in Dryland Wheat Field

LI WenGuang,YANG XiaoXiao,HUANG ChunGuo,XUE NaiWen,XIA Qing,LIU XiaoLi,ZHANG XiaoQi,YANG Si,YANG ZhenPing,GAO ZhiQiang

Scientia Agricultura Sinica. 2019, 52(15): 2664-2677. doi:10.3864/j.issn.0578-1752.2019.15.010

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【Objective】 The experiment was conducted to explore the effects of rapeseed planting as green manure on soil nutrients, enzyme activities and bacterial community in dryland wheat field of Loess Plateau in order to improve farmland fertility. 【Method】The experiment was arranged as two-factor split-plot design including sowing rates (S1: small amount; S2: medium amount; S3: large amount) as main plots and rapeseed composting dates (D1: September 10 as early period; D2: September 20 as medium period; D3: September 30 as late period) as subplots. Soil samples at replanting maize field at local areas were considered as control to compare the soil nutrient and enzyme activities. The high-throughput sequencing and PICRUSt gene prediction analysis method was used to determine soil community composition and metabolic function.【Result】Rapeseed manure increased the soil nutrients, enzyme activity and soil bacterial community and soil organic matter and sucrase activity were increased the most, ranging from 11.7% to 60.5%, and 1.4% to 94.5%, respectively, compared with control. Soil nutrients and enzyme activities were significantly affected by rapeseed sowing rates and soil organic matter, and sucrase activity were significantly affected by rapeseed composting dates. Alkaline phosphatase activity and soil bacterial community were significantly influenced with interaction between sowing rate and compositing date. Soil nutrients, enzyme activities and soil bacterial community diversity in S3D3 group were the highest as compared to other treatments. For bacterial community composition, 19 bacterial populations were identified in 10 soil samples at the phylum level, of which the dominant bacterial population were Proteobacteria, Actinobacteria, Acidobacteria and Firmicutes. Cluster analysis showed that ten treatments could be clustered into four categories, including large amount, medium amount, small amount and control. Results indicated that rapeseed composting could significantly altered soil bacterial community composition. RDA analysis showed that there was a positive correlation between soil nutrients, enzyme activities and Acidobacteria, Betaproteobacteria, Gammaproteobacteria, Alphaproteobacteria, Gemmatimonadetes, Actinobacteria and bacterial diversity. According to the PICRUSt analysis, soil bacterial community had rich metabolic functions and genes encoding metabolism were highest. Amino acid metabolism, carbohydrate metabolism, energy metabolism and environmental information processes were key metabolic function pathways in secondary prediction function classification. Heat map analysis of KEGG demonstrated that rapeseed composting increased the bacterial community associated with soil carbon and nitrogen metabolism.【Conclusion】Sowing amount and rapeseed composting date significantly increased the soil nutrients, enzyme activities of succeeding wheat field and effectively, and improved the composition and diversity of soil bacterial community and enhanced the beneficial bacteria. The introduction of feed rapeseed as green manure during the summer fallow period is beneficial to improve the soil fertility and provide reasonable farming system in the dryland of the Loess Plateau.

Fine Mapping and Candidate Genes Analysis for Regulatory Gene of Anthocyanin Synthesis in Red-Colored Tuber Flesh

XU YunMei, LI YuMei, JIA YuXin, ZHANG ChunZhi, LI CanHui, HUANG SanWen, ZHU GuangTao

Scientia Agricultura Sinica. 2019, 52(15): 2678-2685. doi:10.3864/j.issn.0578-1752.2019.15.011

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【Objective】 The color of tuber flesh is an important agronomic trait, which directly affects the nutritional and commercial value of potatoes. Accordingly, it is an important goal for potato genetic research and breeding improvement. In this study, we mapped the locus controlling red flesh color by bulked segregant analysis (BSA) and fine mapping, and predicted the candidate genes aided by expression analysis, which provides a foundation for gene function characterization, regulation analysis as well as the molecular breeding of colored potatoes. 【Method】 We crossed a red flesh diploid clone with the Sli gene donor to produce F₁, and the F₁ was backcrossed with the red flesh clone, and finally generated a BC₁S₁ diploid population. From the BC₁S₁ segregation population with 300 individuals, the genomic DNA of 18 red-colored flesh and 21 yellow-colored flesh individuals were extracted respectively and used for sequencing, and the locus controlling red flesh was preliminarily mapped by BSA-seq. The locus was fined mapped through genotyping and phenotyping of the recombination plants from 796 BC₁S₁ individuals. Based on reference genomic annotation and qRT-PCR expression analysis, candidate genes were predicted. 【Result】 In this study, BC₁S₁segregating population with red and yellow-colored tuber flesh was constructed. The major locus which regulates related anthocyanin synthesis in potato flesh was mapped on chromosome 10 within a physical distance between 48.70 Mb and 52.20 Mb. Finally, molecular markers were used to locate the gene into a 377 kb genomic interval from 51.47 Mb to 51.85 Mb. There are five annotated genes in this genomic region based on reference genome annotation information, two of them were MYB transcription factors. We predicted that the two genes, PGSC0003DMG400013966 and PGSC0003DMG400013965, were candidate genes controlling red tuber flesh. 【Conclusion】 In this research, the major locus which regulates accumulation of anthocyanin in potato tuber flesh finally was mapped to chromosome 10 with an interval from 51.47 Mb to 51.85 Mb and predicted the candidate genes, PGSC0003DMG400013966 and PGSC0003DMG400013965.

Requirement Characteristics of Mineral Elements in Different Developmental Phases of Kyoho Grapevine

SHI XiangBin,WANG XiaoDi,WANG BaoLiang,WANG ZhiQiang,JI XiaoHao,WANG XiaoLong,LIU FengZhi,WANG HaiBo

Scientia Agricultura Sinica. 2019, 52(15): 2686-2694. doi:10.3864/j.issn.0578-1752.2019.15.012

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【Objective】 Balanced supply of mineral elements is the prerequisite for the high quality and efficient cultivation of grapes. This study was carried to investigate the mineral nutrient requirement of Kyoho grape, so as to provide a theoretical basis for rational fertilization and precise fertilization of grapes.【Method】 Kyoho was used as test material. The whole plant was sampled at different growth stages in 7 consecutive years from 2012 to 2018. The contents of mineral elements in tree were determined, and the demand and proportion of mineral elements in different growth stages were calculated. 【Result】The absorption of mineral elements in Kyoho grapes varied during different growth stages throughout the growing season. The demand for nitrogen, potassium, iron, manganese, zinc and molybdenum from the germination to the initial flowering period exceeded 15% of the total annual demand, and the demand ratio of phosphorus, calcium, magnesium, copper and boron also exceeded 10%. From the beginning of flowering to the end of flowering period, the demand ratio of nitrogen, iron and molybdenum exceeded 15%, and the demand ratio of phosphorus, potassium, calcium, magnesium and zinc exceeded 10%. From the end of flowering to the veraison stage, the demand ratio of each mineral element was 41.7% nitrogen, 47.44% phosphorus, 44.83% potassium, 45.88% calcium, 44.92% magnesium, 39.75% iron, 27.40% manganese, 30.28% zinc, 60.20% copper, 38.72% boron, and 41.59% molybdenum. The demand for potassium, manganese and boron from the veraison stage to the harvesting period was relatively large, accounting for 21.76%, 22.19% and 20.17%, respectively. And the demand ratios of phosphorus, magnesium, calcium and zinc were 17.12%, 16.76%, 16.34% and 14.72%, respectively. While the demand ratio for nitrogen, iron, copper and molybdenum was less than 10%. During the harvesting period to the defoliation period, the demand ratios of manganese and zinc were 28.71% and 23.57%, respectively. The demand ratio of iron and boron exceeded 15%, and the proportion of nitrogen, calcium, magnesium and molybdenum also exceeded 10%. Phosphorus, potassium and copper accounted for 9.72%, 4.78% and 8.69%, respectively.【Conclusion】It should be paid attention to the supply of mineral element at different developmental phases of grapevine. The demand for mineral elements in the production of 1 000 kg of fruit was nitrogen 5.67 kg, phosphorus 2.37 kg, potassium 5.66 kg, calcium 5.70 kg, magnesium 1.02 kg, iron 153.45 g, manganese 53.14 g, zinc 36.25 g, copper 7.28 g, boron 41.84 g and molybdenum 0.47 g. The average contents of mineral elements in dry matter weight were nitrogen 0.92%, phosphorus 0.36%, potassium 0.66%, calcium 0.84%, magnesium 0.15%, iron 269.27 mg·kg ^-1, manganese 57.24 mg·kg ^-1, zinc 49.64 mg·kg ^-1, copper 12.66 mg·kg ^-1, boron 66.35 mg·kg ^-1 and molybdenum1.09 mg·kg ^-1.

Response Surface Design and Multi-Objective Optimization of Apple Slices Dried by Air-Impingement

JIA MengKe,WU Zhong,ZHAO WuQi,LU Dan,ZHANG QingAn,ZHANG BaoShan,SONG ShuJie

Scientia Agricultura Sinica. 2019, 52(15): 2695-2705. doi:10.3864/j.issn.0578-1752.2019.15.013

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【Objective】 In order to obtain the drying process parameters of apple slices with high quality and low energy consumption, the effects of air temperature, slice thickness, air velocity and their interaction on the vitamin C (V_C) content, rehydration ratio and energy consumption were investigated during the air-impingement drying of apple slices. 【Method】 With the air temperature, slice thickness and air velocity as the factors, and the three-factor response surface Box-Behnken response surface design was carried out with the V_C content, rehydration ratio and unit energy consumption of apple slices as the response. The factors and their interactions between the various factors were analyzed, and a quadratic regression model of V_C content, rehydration ratio and unit energy consumption was established and verified by applying three optimization methods, including genetic algorithm, fgoalattain function method and membership degree comprehensive evaluation method, were applied respectively. 【Result】 The factors’ order of influencing on the Vc content was as the follows: Air temperature, slice thickness and air velocity. Regarding the air temperature, both the interactions between the slice thickness and the air velocity were extremely significant, respectively. The factors’ influencing rehydration ratio ordered as the air temperature, air velocity and slice thickness, and all these factors had an extremely significant effect; the interactions between slice thickness and air velocity were significant. The orders influencing on the energy consumption were the slice thickness, air temperature and air velocity. And the air temperature, slice thickness and the interactions between air temperature and air velocity were extremely significant, air velocities and the interactions between air temperature and slice thickness were significant. The established regression model of V_C content, rehydration ratio and energy consumption was statistically significant (P<0.05), suggesting that the model could be used to analyze and predict air-impingement drying parameters. The optimal drying parameters analyzed by genetic algorithm were of 63.24℃ air temperature, 2.00 mm slice thickness and 12.00 m·s ^-1air velocity, respectively. Under these conditions, the V_Ccontent, rehydration ratio and energy consumption of apple slices were 66.96 μg/100 g, 3.83 and 26.49 kJ·g ^-1, respectively; the optimal process parameters obtained by fgoalattain function were as: air temperature 71.62℃, slice thickness 2.37 mm, air velocity 11.18 m·s ^-1, and V_Ccontent was 64.90 μg/100 g, rehydration ratio was 3.41, and unit energy consumption was 25.85 kJ·g ^-1; the optimal process parameters obtained by the comprehensive evaluation method of membership degree were as: air temperature 63.57℃, slice thickness 2.00 mm, air velocity 12.00 m·s ^-1, and V_C content was 66.94 μg/100 g, rehydration ratio was 3.79, unit energy consumption was 26.53 kJ·g ^-1. With the fitness value as the index, it could be concluded that the genetic algorithm optimized results were the best. 【Conclusion】The genetic algorithm could be used for the multi-objective optimization in air-impingement drying apple slices. The optimum parameters were of 63℃ air temperature, 2 mm slice thickness, and 12 m·s ^-1air velocity. With these parameters, the V_C content, rehydration ratio and unit energy consumption under this parameter were 66.85 μg/100 g, 3.78, and 26.59 kJ·g ^-1, respectively. In conclusion, the air-impingement technique could be applied in the drying of apple slices with high V_C content, high rehydration ratio and low energy consumption.

Lentivirus Mediated Interference Silencing MAT2A and MAT2B Inhibited Differentiation of Porcine Intramuscular Preadipocytes

ZHAO CunZhen,YI BenChi,CHEN PeiRong,LI JianZhu,ZHAO YunHuan,ZHU ZhongKe

Scientia Agricultura Sinica. 2019, 52(15): 2706-2715. doi:10.3864/j.issn.0578-1752.2019.15.014

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【Objective】 Methionine adenosyltransferase (MAT), an essential cellular enzyme responsible for S-adenosylmethionine biosynthesis. The purpose of this study was to construct the lentivirus-mediated pLenti-H1 vector and investigated the effect of adenosine methionine transferase MAT2A and MAT2B on the differentiation of porcine intramuscular adipocytes.【Method】Porcine longissimus dorsi tissue was collected from 3 to 7 days piglets under sterile conditions and isolated the porcine intramuscular preadipocytes by differential adhesion method. According to MAT2A gene (Accession No.NM_001167650.1) and MAT2B gene sequence (Accession No.NM_001142832.1), Invitrogen online software BLOCK-iTTM RNAi Designer was used to respectively design MAT2A and MAT2B shRNA target sequence. The synthesized single-chain oligonucleotide was annealed to form double strands DNA, and was ligated with pLenti-Hl vector after BamH I and Xho I (TaKaRa) double digestion, then the plasmid DNA was extracted and further identified by restriction enzyme digestion and sequencing. X-tremeGENE-HP DNA transfection reagent was used to co-transfect 293T cells with the correct recombinant plasmid and packaging plasmid (CMV-Δ8.9 and CMV-VSVG). The expression of green fluorescent protein (GFP) was observed after 48 h and then the virus titer was tested. The primary porcine intramuscular preadipocytes were infected with viruses at 70% to 80% cell density and induced adipogenic differentiation when cells at full confluence. Total RNA was extracted from adipocytes and the mRNA reverse transcription was performed by using a Revert Aid First-strand cDNA Synthesis Kit. The gene primer sequences of MAT2A, MAT2B, PPARγ, aP2, CEBP/α and β-actin were designed by Primer primer 5.The interference efficiency of MAT2A and MAT2B gene on the porcine intramuscular preadipocytes was detected by Real-time quantitative PCR and Western blot. The effects of MAT2A and MAT2B on porcine intramuscular adipogenesis were detected by Oil O stating and RT-qPCR. 【Result】Recombinant lentivirus vector pLenti-Hl-MAT2A/MAT2B was successfully constructed. The virus titer of lentivirus sh-MAT2A and sh-MAT2B were respectively 6.7×10 ⁷ pfu/mL and 7×10 ⁷pfu/mL. After preadipocytes infected with adenovirus for 72 h, Microscopic fluorescence imaging showed 90% of green fluorescent protein (GFP) appeared, indicated that porcine intramuscular preadipocytes were successfully infected by lentivirus sh-MAT2A and sh-MAT2B. Real-time qPCR results showed that the expression of MAT2A and MAT2B was separately decreased 70% and 60% compared with sh-scramble. The Western blot experiment and protein analysis showed that interference with MAT2A, the expression of MAT2A had an approximately 40% decrease and the difference reached high significant level (P<0.01). The expression of MAT2B had a 25% drop when inhibited with MAT2B and the different tendency towards statistical significance (P<0.05). Oil O staining and quantitative analysis showed that, the lipid accumulation of porcine intramuscular adipocytes markedly reduced upon silencing of MAT2A and MAT2B. Real-time qPCR results showed that knockdown of MAT2A and MAT2B inhibited the mRNA levels of PPARγ,aP2 and CEBP/α.【Conclusion】 Lentivirus-mediate sh-MAT2A and sh-MAT2B interference system was successfully esablished. The recombinant lentivirus can effectively reduce the mRNA and protein expression of MAT2A and MAT2B in porcine intramuscular adipocytes. Further experiments showed that interfering with MAT2A and MAT2B genes, the lipid accumulation and adipogenic key genes expression in porcine intramuscular adipocytes were significantly inhibited.

Mutagenesis and Screening of Endophytic Fungus Alternaria Section Undifilum oxytropis Producing Swainsonine from Locoweed

HAO BaoCheng, SONG XiangDong, GAO Yan, WANG XueHong, LIU Yu, LI YuanXi, LIANG Yan, CHEN KeYuan, HU YuYao, XING XiaoYong, HU YongHao, LIANG JianPing

Scientia Agricultura Sinica. 2019, 52(15): 2716-2728. doi:10.3864/j.issn.0578-1752.2019.15.015

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【Background】 Locoweed is referred to as the Astragalus and Oxytropis of poisonous plants, Alternaria Section Undifilum oxytropis is a kind of fungus with the ability to produce swainsonine (SW) isolated from locoweed. On one hand, Swainsonine exhibits good inhibition of tumor cell growth, invasion and metastasis, and potential anti-HIV and other medicinal activities. On the other hand, cattle and sheep can be poisoned by eating a large number of locoweed grass by mistake, which has caused serious harm to the healthy development of grassland animal husbandry and attracted extensive attention of researchers. However, the biosynthesis mechanism of producing SW in the endophytic fungus Alternaria Section Undifilum oxytropis is not clear, which seriously restricts the subsequent research and clinical application of swainsonine for anti-tumor mechanism by biological fermentation. And by means of genetic engineering of locoweed detoxification breeding, make locoweed edible and non-toxic natural forage for cattle and sheep.【Objective】it is urgent to clarify the biosynthesis mechanism of swainsonine- producing of Alternaria Section Undifilum oxytropis by using effective research methods.【Method】 Using Alternaria Section Undifilum oxytropis as the starting strain, ultraviolet irradiation mutagenesis, chemical mutagenesis of nitrosoguanidine and ultraviolet irradiation-NTG mutagenesis were used respectively. The mutagenic screening was carried out under the conditions of different mutagenesis time and mutagenesis dosage. By measuring the lethal rate of strains under different mutagenesis conditions, fermentation culture, continuous subculture of 5 generations and using alpha-mannosidase activity analysis method to detected the changes of swainsonine content, the optimal mutation conditions of different mutagenesis methods were optimized. The dominant mutant strains were inoculated into Potato Dextrose Agar (PDA) and Modified Czapek-Dox Medium, and the growth cycle curves of mutant strains D4 and UD1 were determined and plotted.【Result】After treatment with the above three mutagenesis methods, three mutant strains of U4, D4 and UD1 were obtained, which can be cultured steadily and continuously, and the content of swainsonine varies greatly. The optimum mutagenesis conditions were as follows: ultraviolet irradiation for 160 seconds, chemical mutagenesis of nitrosoguanidine for 6 μL and 5 min, ultraviolet irradiation-NTG mutagenesis for 20 seconds and 2 μL for 5 min. U4, D4 and UD1 mutant strains were smaller in colony morphology and protruded in the middle than original strains, and the color of colony was pink or white. And the content of swainsonine in the production of swainsonine had significant changes. Among them, the production of swainsonine of U4 mutant strain increased by 16.02% (P<0.01), D4 mutant strain decreased by 23.58% (P<0.01), and UD1 mutant strain increased by 21.87% (P<0.01). However, the growth cycle of D4 and UD1 mutant strains were the same as that of the original strain, which were 24 days.【Conclusion】By using ultraviolet irradiation, chemical mutagenesis of nitroguanidine and ultraviolet irradiation-NTG mutagenesis, U4, D4 and UD1 of mutant strains were successfully screened out, whose content of swainsonine was different from that of the original strain. This provides a basis for the subsequent use of molecular biological means to explain the key genes of Endophytic Alternaria Section Undifilum oxytropis and key enzymes in its biosynthesis mechanism of swainsonine.

Artificial Simulation of Hill-Drop Drilling Mechanical Technology to Improve Yield and Lodging Resistance of Early Season Indica Rice

YI YanHong,WANG WenXia,ZENG YongJun,TAN XueMing,WU ZiMing,CHEN XiongFei,PAN XiaoHua,SHI QingHua,ZENG YanHua

Scientia Agricultura Sinica. 2019, 52(15): 2729-2742. doi:10.3864/j.issn.0578-1752.2019.15.016

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【Objective】This study investigated the effects of hill-drop drilling mechanical technology with furrowing on the yield-related traits and lodging resistance of early season indica rice, which provided theoretical basis and technical support for the mechanical direct-seeding technology. 【Method】Two indica rice varieties, including inbred rice Zhongjiazao17 and hybrid rice Zhuliangyou171, with three treatments (hill-drop drilling mechanical technology with furrowing (MFP), surface bunch planting (SBP) and soil covering bunch planting (SCP)) were used to compare the effects on seedling emergence rate, yield-related traits and lodging resistance of rice. 【Result】The results showed that compared with SBP and SCP, MFP increased seedling emergence rate of early season indica rice by 5.19% to 13.89%, and the difference was significant (P<0.05). At the same time, MFP was conducive to improving yield of direct seeding rice. Yield increase rate of the two varieties was ranged from 4.52% to 11.20%, and yield of inbred rice Zhongjiazao17 was significantly different to the others. From the analysis of yield components, the increase in yield was mainly due to the synergistic improvement of effective panicles per unit area and 1000-grain weight. In addition, MFP was beneficial to improve resistance of plant and reduce lodging index, especially the upper internode, and it was beneficial to increase height, gravity center height, culm wall thickness and internode diameter of upper internode (I3), and increase dry weight per unit length of internode, dry weight per unit volume of internode and lignin. There was positive correlation between internode dry weight and breaking resistance, and negative correlation with lodging index. Therefore, dry weight, and dry weight per unit length of internode were the main factors for affecting lodging. Plant height, gravity center height, internode length and internode diameter could not both affect lodging resistance and lodging index. 【Conclusion】 MFP could improve the grain yield of direct seeding early indica rice, and also enhance plant lodging resistance, decrease lodging risk. It could be popularized in the production.

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