2022 Vol. 37, No. 7
Display Method:
2022, 37(7): 817-823.
doi: 10.19303/j.issn.1008-0384.2022.007.001
Abstract:
Objective This study explored the key genes of sweet corn sweetness formation and the possible molecular mechanism of heterosis. Method Genotypes and expressions of sucrose synthase gene family of a super-sweet corn variety, Minshuangse No.6, and its parents were analyzed using bioinformatics, resequencing, transcriptome, and other techniques to unveil the underlining basis of the sweet taste of corns. Result Eighteen sucrose synthase genes were isolated from the corn kernels. Among them, Zm0001d029087 was found to belong to the same subfamily as Sh1, Sus1, and Sus2/3 with close evolution relationships. It might play a role in the sugar metabolism of the corn. Comparing both parents with B73, mutations were found in Sh1, Sus1, and Sus2/3. Of the 18 genes, only Zm0001d029087 and those 4 genes expresses in the kernels. Further analyses showed the 4 genes, except Sh1, had significantly lower expressions in Minshuangse No.6 than in both or one of the parents. Conclusion The genetic variations in the super-sweet Minshuangse No.6 revealed a unique characteristic of Zm0001d029087 that might relate to the sweetness of the corn kernels. A preliminary role of heterosis in sugar formation by that gene was proposed for further investigation.
2022, 37(7): 824-832.
doi: 10.19303/j.issn.1008-0384.2022.007.002
Abstract:
Objective Feasibility of using images generated by unmanned aerial vehicle (UAV) to estimate the aboveground biomass (AGB) on a rice field was evaluated for crop production prediction. Methods On fields of two different varieties of rice fertilized with 4 varied nitrogen applications, AGB of rice plants at tillering, booting, and full heading stages were recorded by using the UAV imaging technology. Data on color and texture measurements were extracted from the images to correlate with corresponding AGB. A mathematic model was constructed, tested, and validated for prediction accuracy. Result On color, the red and blue differentiation (r-b) of the images highly correlated with the AGB; on texture, it was the G-mean. A prediction model was thus obtained for the entire growth period as y=2 544.507+5 054.243x1−145.543x2−556.553x1x2+27 379.41x12+3.927x22 , which had a correlation coefficient (R2) of 0.920 2 and a test determination coefficient of 0.911 2. Conclusion The prediction model based on r-b and G-mean derived from the UAV images performed satisfactorily in monitoring the AGB for the entire growth period of rice in the field. It was conceivably applicable for the farming operation and crop management.
2022, 37(7): 833-840.
doi: 10.19303/j.issn.1008-0384.2022.007.003
Abstract:
Objective Effects of the widely distributed, important plant growth and stress resistance regulating arbuscular mycorrhizal (AM) fungi on sorghum growth under varied nitrogen (N) deposition in soil were studied on the terrestrial ecosystem. Method Growth of Sorghum hicolor (L.) Mocrnch seedlings inoculated with either Glomus mosseae or inactivated G. mosseae (CK) in pots under varied N addition of 0, 200, 400, or 500 mg·kg-1 (refer to as N0, N1, N2, and N3, respectively) in a greenhouse was monitored. Mycorrhizal colonization in rhizosphere soils was determined after two weeks, while the biomass, N, and P of the plants in 16 weeks of cultivation. Result ① The AM fungi inoculation significantly increased the mycorrhizal colonization on sorghum roots (P＜0.001) at a decreasing trend with increasing N addition. ② Both the aboveground and total biomasses of the sorghum plants grown under N0 were significantly enhanced by the presence of the AM fungi but inhibited by it under N3 (P＜0.05). ③ Similarly, AM fungi increased the N and P contents and N/P ratio in the plant tissues by N0 but did the opposite under either N2 or N3 (P＜0.05). However, under N2 the AM fungal inoculation exerted no significant effect on P content (P＞0.05). And ④ the mycorrhizal growth effect (MGR), mycorrhizal N-uptake effect (MNR), and mycorrhizal P-uptake effect (MPR) on sorghum changed from positive to negative gradually as the N addition increased. Conclusion Inoculating AM fungi on sorghum seedlings and adding N in soil interactively affected the biomass and N-P uptake of the plants significantly. Without N addition, the AM fungi enhanced the accumulation of biomass, N, and P, but N addition maximized the mycorrhizal effect at certain level. High levels of N in soil could be detrimental to the growth of AM fungi and altered the symbiosis.
2022, 37(7): 841-849.
doi: 10.19303/j.issn.1008-0384.2022.007.004
Abstract:
Objective Genes related to the cocoon shell ratio of Bombyx mori were investigated for improvement on silkworm productivity. Method Segregated BC1 populations of a highly productive silkworm, Jingsong, and a moderately productive Furong were established. DNA pools were constructed by mixing 30 high and low cocoon shell ratio individuals from the BC1 male populations. BSA-seq was applied to identify the regions relevant to the target trait. The coding genes at the candidate regions were annotated with BLAST software in GO and KEGG databases. Result The percentage of clean reads that matched the reference genome of P50 was 98.86%, and those of the average genome coverage 95.79% for 1× and 88.63% for 5×. Variant calling resulted in 26 557 646 SNPs. Three QTLs for the cocoon shell ratio detected by ∆(SNP-index) were in the intervals of 4 430–4930 kb on Chr.2, 12350–12920 kb on Chr.4, and 3230–3730 kb on Chr.13. There were 70 coding genes found in the associated regions. According to the GO database annotation, 58 genes were categorized in the groups of biological process, molecular function, or cellular component. The 19 genes annotated in the KEGG database distributed in 34 metabolic pathways. Of which, 10 might play important roles in regulating the cocoon shell ratio and the functions involving the silk gland cell movement, energy metabolism, and/or protein synthesis. Conclusion The genes related to the silkworm cocoon shell ratio were identified by BSA-seq method. Ten genes were speculated to possibly associate with the silk formation. The present study only managed to locate the regions on chromosomes 2, 4, and 13 of the genes in B. mori that might related to the cocoon shell ratio. Further study will be needed to finely map and clone the key regulatory genes in the highly complex regulatory mechanism.
2022, 37(7): 850-854.
doi: 10.19303/j.issn.1008-0384.2022.007.005
Abstract:
Objective ORFV 115 was cloned for a study on the gene. Method Oligo 7 software was used to design and select primers for specific amplification of the gene. Using the genome of ORFV FJ-ND as template, the sequence was obtained by PCR. The gene was then cloned into pGEX-6p-1 to obtain the recombinant plasmid pGEX-6P-115 for sequencing and identification prior to transformation to RosettaganmiB (DE3) receptor cells. Expression conditions of the recombinant fusion protein were optimized with respect to IPTG concentration and induction time. SDS-PAGE was used to analyze the expressed target protein. Result Conclusion
2022, 37(7): 855-868.
doi: 10.19303/j.issn.1008-0384.2022.007.006
Abstract:
Objective Polyamine metabolism and expression of cold tolerance genes associated with the mechanism of melatonin in alleviating low temperature stress in tomato were investigated. Method Solutions of melatonin in the concentrations of 50, 100, 200, and 300 µmol·L−1 were sprayed on the leaves of Dongnong 708 tomato plants (Solanum lycopersicum). Under low temperature, optimal concentration of melatonin for the stress alleviation was determined according to the malondialdehyde content and electrolyte leakage rate in the leaves. Effects of the treatment on the growth, polyamine metabolism, and cold tolerance gene expression, as well as those of putrescine (Put) synthesis inhibitor and melatonin pretreatment on polyamine content and antioxidant characteristics, of the plants were determined. Result Pretreating the tomato plans with melatonin prior to low temperature exposure lessened the seedling growth retardation induced by the stress. The plant height and fresh/dry weights as well as the Put in leaf at all stages of the stress imposition were significantly increased. The contents of spermidine (Spd) and spermine (Spm) rose significantly on the 2nd day after low temperature treatment before tapering off. The arginine (Arg) content, arginine decarboxylase (ADC) activity, and ADC synthesis-related gene expressions became significantly higher with the melatonin pretreatment, while the Put catabolic enzyme diamine oxidase (DAO) activity and gene expression significantly declined. A challenge test confirmed that, under low temperature stress, the Put synthesis inhibitor in the arginine pathway significantly reduced the melatonin-induced enhancements on Put accumulation and antioxidant enzyme activity, which would otherwise provide a protective effect on the cell membrane. Additionally, the expression of cold tolerance genes related to Put in tomato leaves was upregulated with the presence of melatonin. Conclusion Melatonin positively regulated the accumulation, but inhibited the degradation, of Put mediated by arginine. The arginine mediated Put synthesis pathway played an important role in the antioxidant defense of the tomato plants improved by melatonin. In addition, melatonin might also increase the expression of cold tolerance genes by way of promoting the Put synthesis to further boost the cold tolerance of tomato seedlings.
2022, 37(7): 869-879.
doi: 10.19303/j.issn.1008-0384.2022.007.007
Abstract:
Objective Members of the amaranth TCP gene family were identified based on the transcriptome database for an in-depth understanding on the roles they associated with the growth, development, and abiotic stress of the plant. Method Members of the TCP gene family were identified by screening the transcriptome database on Dahong amaranth (Amaranthus tricolor L.) for a bioinformatics analysis. Amaranth seedlings were cultured under different conditions and their expressions under different treatments analyzed by qRT-PCR. Results Amaranth TCP gene family has 14 members, all localized in the nucleus. The length of AtrTCP protein was in the range of 230–721 aa, the predicted relative molecular weight was 25.25–78.57 kD, the isoelectric point was 6.15–9.45, and it contained 15 conserved motifs. Except AtrTCP11, which was stable protein, all the other proteins were unstable. Two AtrTCP family members, AtrTCP2 and AtrTCP6, were predicted as miR319 target genes by miRNA. qRT-PCR showed differentiated expressions of the family members under salt solutions of varied concentrations (i.e., 0, 50, 100, and 200 mmol·L−1). The expression of the upregulated AtrTCP10 reached a significant level under blue light, and so did those of the downregulated AtrTCP2, AtrTCP3, AtrTCP8, AtrTCP9, AtrTCP11, and AtrTCP13. Under different concentrations of ammonium nitrate ratio (0∶0, 0∶10, 3∶7, 5∶5, 7∶3, 10∶0) treatment, the expressions of the TCP genes differed. AtrTCP3 was shown to be involved in the entire nitrogen metabolism process. In tissues of amaranth, AtrTCP3 and AtrTCP12 were highly expressed in leaves, while the others in roots. Conclusion Depending on the treatments, the expressions of the amaranth TCP gene family members differed. It suggested a broad spectrum of involvements by the members associated with abiotic stresses on amaranth.
2022, 37(7): 880-885.
doi: 10.19303/j.issn.1008-0384.2022.007.008
Abstract:
Objective A thioredoxin gene, CsTRXh1, was cloned from Citrus sinensis to determine the expression and subcellular localization for studying its function and role played in stress response. Method CsTRXh1 from the homology sequence in the genome of C. sinensis was cloned. Homology, phylogenetic relationship, and physicochemical properties of the gene were analyzed, and expressions in healthy and Huanglongbing-infected trees detected. The transient expression of the gene in tobacco leaves was used to find its subcellular localization. Result The successfully cloned CsTRXh1 was assigned with the GenBank accession ON125405. A multi-protein sequences alignment showed that it contained a conserved thioredoxin domain with a high similarity with other plant thioredoxin proteins. The phylogenetic analysis indicated it to be an h-type thioredoxin protein. CsTRXh1 was upregulated in the leaves of Huanglongbing-infected trees and localized in the cytoplasm and cytomembrane. Conclusion The expression induced in the Huanglongbing-infected trees revealed a possible association of CsTRXh1 with the physiological and biochemical regulations of insect-disseminated Candidatus Liberibacter asiaticus that causes the destructive, incurable citrus greening disease.
2022, 37(7): 886-896.
doi: 10.19303/j.issn.1008-0384.2022.007.009
Abstract:
Objective Characteristics and phylogeny of chloroplast genomes of the medicinally and economically valuable species in Panax genus were studied. Methods Using bioinformatics software, the properties, repeats, structural variation, evolution, and phylogeny of the genomes of chloroplasts from 14 ginseng species were analyzed. Results The genomes consisted of typical quadripartite structure with 114 unique genes. The long repeats in them were mainly of palindromic and forward types with a length between 30 bp and 39 bp. The simple sequence repeats were largely A/T type and most abundantly mononucleotides. No gene rearrangement occurred in the genomes was observed. The boundary between the inverted repeat region and the single copy region was highly conserved. Of the 12 regions with highly variable nucleotides, 7 were in the large and 5 in the small single copy region. Indicated by the dN/dS ratios, the positive selection could occur on clpP, ycf1, and ycf2 with unknown functions. The phylogenetic analysis showed that P. stipulenatus and P. trifolius were in the basal lineage, the tetraploid P. ginseng and P. quinquefolius separated from other diploid species, while P. notoginseng, P. japonicus, and P. vietnamensis closely related. Conclusion The chloroplasts of the ginseng species examined were basically same in number and order of genomes, conservative in structure, but divert in number and type of repeats. The nucleotide polymorphism of the chloroplasts was higher in single copy region than inverted repeat regions. The positive selection genes identified in the study might result from the ecological adaptation of these Panax species.
Correlation between Changes on Endogenous Hormones and Embryo Abortion of Ornamental Crabapple Seeds
2022, 37(7): 897-903.
doi: 10.19303/j.issn.1008-0384.2022.007.010
Abstract:
Objective Correlation between the changes on endogenous hormones and embryo abortion of ornamental crabapple seeds was investigated. Method Ornamental crabapple varieties, Malus Red Jewel with low abortion rate and M. Kelsey with high abortion rate, were compared on the endogenous hormones, including gibberellin GA3, abscisic acid ABA, cytokinin CTK, and indoleacetic acid IAA, in the seeds during fruit growth and development. The dynamic changes were correlated to the seed embryo abortion rate. Results There was significant difference on the fruit setting rate between M. Red Jewel and M. Kelsey (P＜0.05) as that of M. Kelsey declined rapidly from one to 13 d and became stable at 54 d after pollination. In the early stage of embryonic development, the contents of GA3 and IAA and ratios of GA3/ABA and (GA3+IAA+CTK)/ABA in the seeds of M. Red Jewel were significantly higher than those of M. Kelsey (P＜0.05). Conversely, in the later stage, the GA3, ABA, IAA, IAA/ABA, GA3/ABA, and (GA3+IAA+CTK)/ABA of M. Red Jewel became significantly lower than those of M. Kelsey (P＜0.05). Conclusion The physiological fruit-dropping of M. Kelsey occurred in 1–13 d after pollination. It was the optimum time to alter the fruit-setting and improve the ornamental value of an M. tree. Embryonic abortion of both varieties of the crabapple took place within 54 d after pollination. Most of the fruits with aborted embryos did not fall off the tree and continued to grow to maturity due possibly to the increased GA3 and (GA3+IAA+CTK)/ABA ratio in the seeds. Consequently, maintaining a high content of GA3 and IAA in the early stage could ensure a normal seed development. Once reached the late stage, no individual hormone, short of low level GA3 and IAA, could warrant a normal embryonic development.
2022, 37(7): 904-911.
doi: 10.19303/j.issn.1008-0384.2022.007.011
Abstract:
Objective Growth of young Chinese fir trees under 5 cultivation models were studied for the forest building. Method In a span of several years, 5 forest building models were implemented for the experimentation on Cunninghamia lanceolata. Young plants were cultivated according to a randomized block design of 5 existing models, i.e., Yang 020, Yang 061, Guangxi 2G, Fujian Pushang 3G, and the mixed Yang 020/061. The average diameter at breast height (DBH), tree height, east-west crown width, north-south crown width, individual standing timber volume, and trunk girth classification of the plants were continuously measured throughout the growth period. Results Significant deviations in DBH, height, crown width, and timber volume were found among most of the trees under different cultivation methods. The differences in DBH, height, and canopy growth were not significant between Yang 061 and Yang 020/061. The stand structure was uniformly distributed under Yang 061. Under Fujian Pushang 3G, a normal distribution on the trunk girth classifications with a solid spatial structure of the fir was observed. Yang 020/061 and Yang 061 had the greatest proportions of trees in the 8-12 cm diameter classes at 60.45% and 41.81%, respectively. Conclusion The growth of the Chinese fir trees under the cultivation model of Yang 061 showed the highest indices and abundant large-diameter trunks among 5 models. It provided the young forest with desirable development environment and was consider a high-efficiency approach to building forests of Chinese fir in the wild.
2022, 37(7): 912-920.
doi: 10.19303/j.issn.1008-0384.2022.007.012
Abstract:
Objective Key functional components and in vitro antioxidant activities of 4 types of Hongqu (Monascus-rice fermentation paste) were determined for product development. Method Color value, monacolin K (MK), γ-aminobutyric acid (GABA), ergosterol, and polysaccharide of Functional Qu (FQ), Coloring Qu (CQ), Wuyi Qu (WQ), and Gutian Qu (GQ) were measured by means of UV-Vis, colorimeter, and HPLC. Antioxidant activity of the Hongqu was determined by in vitro chemical assays including the ferric ion reducing antioxidant power (FRAP) and 1,1-Diphenyl-2-picrylhydrazyl (DPPH) and 2,2'-Azinobis-(3-ethylbenzthiazoline-6-sulphonate (ABTS) radical scavenging capacities. Correlation between the functional components and the antioxidant activities of Hongqu was analyzed using SIMCA and SPSS software. Result The Hongqu specimens varied in the following aspects. CQ was measured significantly higher on orange, yellow, and red color value than FQ, GQ, and WQ, while GQ on orange, yellow, and red color value than FQ and WQ, and FQ on orange color value than WQ. FQ contained significantly more MK than CQ, GQ, and WQ, whereas WQ significantly more GABA than CQ, FQ, and GQ, but WQ and FQ significantly more ergosterol than CQ and GQ, and FQ had the highest content of polysaccharides, which was followed by CQ. The FRAP and DPPH and ABTS scavenging abilities of CQ were significantly higher than those of FQ, WQ, and GQ, and FQ was stronger in FRAP than WQ or GQ. The color value of Hongqu positively correlated with FRAP (0.733 ≥ r ≥ 0.703) and negatively with the scavenging 50% DPPH (−0.896 ≤ r ≤ −0.880) and ABTS (−0.773 ≤ r ≤ −0.758). It appeared that pigment was the critical antioxidant components in the Hongqu. On the other hand, neither MK, GABA, ergosterol, nor polysaccharides significant correlated with the in vitro antioxidant activity of the 4 Hongqu. Conclusion An extremely significant correlation between the pigment and antioxidant activity were demonstrated in CQ more than the other 3 Hongqu. In the development of natural antioxidant products, Monascus pigment
2022, 37(7): 921-928.
doi: 10.19303/j.issn.1008-0384.2022.007.013
Abstract:
Objective Effect of rocking-withering in processing Wuyi rougui tea on the metabolites in leaves was analyzed using GC-TOF-MS non-targeted metabonomics. Method Freshly plucked buds and leaves from Wuyi rougui tea bushes were processed according to the conventional northern Fujian technique with or without (CK) the rocking-withering procedure. The non-targeted metabolic analysis was performed to obtain data for differentiating the metabolites in the leaves by multivariate and univariate statistical analyses. A KEGG pathway enrichment analysis was conducted to identify the associated metabolic pathways. Result Compared with the conventional brief withering under the sun, the different metabolites of tea leaves without rocking (CK) and after rocking-withering were 21 and 14; meanwhile tea leaves after rocking-withering had 9 significantly upregulated and 3 downregulated metabolites compared to leaves without rocking (CK) . The most significant differentiations were found in the metabolites such as shikimic acid, citric acid, L-malic acid, raffinose, and maltose. Conclusion Rocking-withering stimulated the tea leaves to produce certain intermediate products in the tricarboxylic acid cycle and caused a reduction on shikimic acid. It was the metabolisms of amino acids and carbohydrates that were largely affected. The significantly reduced shikimic acid and increased phenylalanine in LY7M metabolite might play a role in the synthesis of aromatic compounds that give the oolong tea its characteristic sensory quality.
2022, 37(7): 929-937.
doi: 10.19303/j.issn.1008-0384.2022.007.014
Abstract:
Objective The process to freeze-dry kiwifruits was optimized using an ultrasonic-assisted sugar osmotic pretreatment to shorten the drying time and improve the product quality. Method Single factor tests were conducted to determine the ranges of sugar concentration as well as ultrasonic application time, temperature, and power for the pretreatment prior to process optimization by a Box-Behnken response surface experiment. Result The time required to freeze-dry kiwifruits increased significantly when the treatment temperature was raised, especially, beyond 40℃. On the other hand, the time was shortened as the ultrasonic power and sugar concentration increased. Prolonged ultrasonic application also reduced the drying time to a leveled off minimum. The optimized pretreatment applied 200W ultrasound at 24℃ for 50m on fresh kiwifruits impinged with 45% (w/w) sugar. The freeze dehydration took 43.07h to yield kiwifruit pieces with a hardness measurement of 14,616.01g, a chewiness of 7,795.61mJ, a vitamin C content of 0.19%, and a total sugars content of 62.82%. The sensory evaluation rated the test product much superior to control without pretreatment. Conclusion The freeze-drying process optimized with ultrasonic-assisted sugar osmotic pretreatment on kiwifruits required significantly shortened dehydration time and produced products with superior quality in comparison with the conventional technology.
2022, 37(7): 938-945.
doi: 10.19303/j.issn.1008-0384.2022.007.015
Abstract:
Objective Conditions for optimal fermentation of Bacillus cereus BCCY-22, which is known to be capable of effectively controlling a variety of nematode diseases, were determined. Methods Using OD600 of the fermentation broth as the indicator, optimal culture conditions for the process were determined with a single factor and response surface experimentation. Results High temperature, low initial pH, and restricted oxygen supply significantly governed the bacterial growth. The finalized process was carried out at 21.5 ℃ with an initial pH at 7.3 and inoculation of the seeding broth at 3% to fill 23% in a flask for 36 h. Conclusion The optimization shortened the fermentation time by 6 h and increased the biomass by 135.94%. The improvements materially provided the basis for industrialized utilization of B. cereus BCCY-22 as a biocontrol agent.
2022, 37(7): 946-953.
doi: 10.19303/j.issn.1008-0384.2022.007.016
Abstract:
Objective Screening bacteria with phosphate-solubilizing ability in Coix were identified and provide excellent strain resource for bio-fertilization agent. Methods Endophytic bacteria were isolated and purified from specimens the roots, stems, and leaves of 25-d-old seedlings of Coix lacryma-jobi L. Abilities of the isolates in dissolving organophosphate and inorganic phosphate as well as in secreting phosphatase were determined. In a pot experiment, effects of two selected isolates on the growth of Coix seedlings were examined. Results Eight strains of bacteria capable of dissolving organophosphate and 5 of degrading inorganic phosphate were isolated. In the 5-d culture supernatants, the highest concentration of phosphorous converted from organophosphate at 37.20 mg·L−1 was reached by R24, and that from inorganic phosphate at 62.93 mg·L−1 by L21. The enhancing effects on plant height, stem girth, and tillering number of the potted Coix seedlings by each and mixture in equal proportion of the two supernatants ranked in the order of L21＞R24＞mixed bacterial liquid[ V （R24）∶ V （L21）=1∶1]. The 16S rDNA sequence phylogenetic analysis identified R24 as Bacillus pumilus and L21 as B. velezensis. Conclusion The phosphobacteria L21 and R24 displayed a significant effect in promoting the growth of Coix seedlings.
2022, 37(7): 954-960.
doi: 10.19303/j.issn.1008-0384.2022.007.017
Abstract:
Objective Effects of application of aquatic green manure Azolla on fertilizer use reduction and productivity improvement for single-cropping rice farming were studied. Method An experimentation using Azolla at a rate of 30 t·hm−2 to replace 20%, 40%, and 60% N and K fertilizers was conducted. The resulting grain yield, plant biological characteristics, and soil fertility were monitored. Results In comparison to the conventional fertilization, the application of Azolla to achieve 20% reduction on the use of N and K fertilizers rendered significant increases on plant height, effective tillers count, and panicles per plant with an 11.11% rise on the crop yield (P＜0.05). The pH, organic matters, alkali-hydrolyzed N, available P, and readily available K of the treated soil were improved to varying extents. In general, plowing Azolla into the field significantly increased organic matters in the soil (P＜0.05). The treatment to reduce 60% use of conventional chemical fertilizers with Azolla (T6) made a significantly difference on the readily available K in soil (P＜0.05). Conclusion Application of Azolla at a rate of 30 t·hm−2 to replace 20% of N and K for fertilization could significantly upgrade the soil fertility and increase the grain yield by 11.11%. It was considered an effective means not only to conserve fertilizer with green manure but also benefit the production of single-cropping rice farming.
