2020 Vol. 35, No. 5
Display Method:
2020, 35(5): 465-473.
doi: 10.19303/j.issn.1008-0384.2020.05.001
Abstract:
Objective The CRISPR/Cas9 technology was applied to edit the Badh2 in rice to enrich the fragrance of current japonica varieties for marketing enhancement. Method A CRISPR/Cas9-BADH vector was constructed to transform 3 elite japonica rice, Longdao 18, Longdao 24, and Xiushui 134. The mutant badh2 was identified by sequencing, and potential off-target mutations examined. Contents of the aromatic 2-acetyl-1-pyrroline (2AP) in the mutant rice cultivars was determined by gas chromatography-mass spectrometry. Result Of the 30 T0 transgenic plants, 24 were found to contain the target mutant badh2, of which, 53.3% were heterozygous, 16.67% homozygous, and 10% bi-allelic. Seven homozygous mutation genotypes were obtained in the T1 non-transgenic mutant plants. There was no off-target mutation detected at all 5 potential sites indicating that a high specificity of the designed sgRNA for the predicted site. Interferences by the varied genome backgrounds of the rice varieties might have caused the significantly varied amounts of the aromatic 2AP detected in all badh2 frame-shift mutant rice. Conclusion The CRISPR/Cas9 technology could effectively induce desired Badh2 mutation in rice. Improvement on the fragrance for 3 japonica rice could lead to wide applications in cultivating new varieties with added commercial value. More interestingly, the significant variations on 2AP content among the mutant rice as discovered in this study would help further the understanding on the genetics associated with aroma rice breeding.
2020, 35(5): 474-479.
doi: 10.19303/j.issn.1008-0384.2020.05.002
Abstract:
Objective Structure and function of OsBI-1L-8 promoter were studied to decipher the mechanism of OsBI-1L genetic family involved in the life of Oryza sativa L. Method Length of pOsBI-1L-8 was predicted using the online software BDGP, Softberry, and Promoter 2.0. The cis-acting regulatory elements of pOsBI-1L-8 isolated from the genomic DNA of Nipponbare were analyzed based on the PlantCARE database. The pOsBI-1L-8::GUS vector was then constructed and transformed into rice callus, and spatiotemporal expression characterization by histochemical staining. Result The length of pOsBI-1L-8 was determined to be 1 258 bp by the predictive analysis and PCR amplification. The region consisted of several cis elements associated with light signal, response to anaerobic stress, and hormone regulation. The GUS reporter gene driven by pOsBI-1L-8 was expressed only during the heading period at the stem-stem junctions, root-stem junctions, and stamens. Conclusion pOsBI-1L-8 was a tissue-specific promoter. OsBI-1L-8 gene was postulated to play an important role in the growth and stamen development of a rice plant.
2020, 35(5): 480-488.
doi: 10.19303/j.issn.1008-0384.2020.05.003
Abstract:
Objective Derived from fertilization models, utilization of organic fertilizers to partially replace NPK for peanut farming in Fujian was investigated. Method In the major peanut producing areas in Fujian, 105 field experiments were conducted in recent years to examine the response of peanut plants to NPK fertilization. Applying the systematic cluster analysis combined with significant test of difference, various fertilization categories for the planting fields were established. A ternary non-structural fertilizer response model was constructed to arrive at recommend fertilizations for each category. Based on the models, field experiments were carried out to test replacement of NPK with an organic fertilizer. Result According to the significant differences on effectiveness of NPK fertilizations, 4 categories of peanut fields were generated as (1) high yield paddy, (2) medium yield paddy, (3) medium-to-low yield field, and (4) low yield field. To maximize the fertilization effect and peanut yield for the fields, 4 optimized models were formulated to obtain the recommended NPK applications. In 34 controlled field experiments, on average, a 10.2% yield increase over the conventional practice was realized by following the recommendation of the models. Meanwhile, although the usage of N decreased 24.9% and of P 38.1%, that of K increased 79.3%. Financially, the cost on fertilizer was reduced to 63 yuan·hm−2 and the net revenue increased to 2 877 yuan·hm−2. Furthermore, by replacing 25% of NPK with a commercial organic fertilizer resulted in the highest peanut yield among all treatments. The substitution increased peanut yield by 10.6% and revenue by 1 595 yuan·hm−2over the recommended NPK application. Conclusion It appeared that a 25% replacement of NPK with the organic fertilizer based on the recommended fertilization could be most profitable for the peanut farming in Fujian.
2020, 35(5): 489-494.
doi: 10.19303/j.issn.1008-0384.2020.05.004
Abstract:
Objective A new high-yield, high-quality soybean variety for fresh bean consumption was bred through sexual hybridization of pedigrees and cultivated in regional trials to determine production performances. Method Hybridized by using Fuxian 5 as the female parent and Yundou 9 as the male parent, a pedigree line coded 08B3-1 was generated. In the spring of 2013 trial, the newly bred variety demonstrated yield traits and bean quality significantly higher than those of the reference, Maodou 3. It was then named Mindou 7 and submitted for demonstration in the annual regional trials in the province on new soybean varieties for fresh bean consumption. Result In the 2013 trial, Mindou 7 showed an average fresh pod yield of 11 459.40 kg·hm−2, which was 2.25% higher than that of Maodou 3. In the subsequent provincial regional trials in 2015 and 2016, it delivered an average fresh pod yield of 9 625.50 kg·hm−2, which was 1.76% higher than that of Maodou 3. Again, in 2017, the yield was 9 780.45 kg·hm−2, impressively 5.68% higher than that of control. The new variety was approved and released by the Fujian Provincial Committee of Crop Variety Identification in April 2018. Conclusion The mid-season-maturation Mindou 7, with its large pods and beans, palatable taste and flavor as well as tender texture after cooking, was considered a premium variety for fresh soybean consumption and suitable for spring planting in Fujian.
2020, 35(5): 495-502.
doi: 10.19303/j.issn.1008-0384.2020.05.005
Abstract:
Objective The SQE genes of Dendrobium officinale associated with the key enzyme involving in the sterol biosynthesis, squalene monooxygenase, were cloned for bioinformatics analysis and determination of their expressions in the stems and leaves of the orchid plant at different growth stages. Method The 3'RACE primers of DoSQE1 and DoSQE2 were designed based on SQE fragment with the 5' terminal from the transcriptome data of D. officinale. The full lengths cDNAs of DoSQE1 and DoSQE2 were cloned and a bioinformatics analysis carried out. Expressions of the genes in the stems and leaves in August, October and December were detected by qRT-PCR. Result The full-length of DoSQE1 was 1 796bp (GenBank accession MT160182) containing an 1 554 bp ORF encoding 517 amino acids (aa) and that of DoSQE2 1 963 bp (GenBank accession MT160183) containing an 1 578 bp ORF encoding 525 aa. DoSQE1 had two transmembrane regions at 4–22 aa and 55–72 aa, while DoSQE2 had only one transmembrane region at 5–23 aa. DoSQE1 contained a squalene epoxidase domain at 204–476 aa, and DoSQE2 at 211–484 aa. The phylogenetic analysis showed DoSQE1 to be closely related to SQE of Phalaenopsis equestris (XP_020599860.1), and DoSQE2 to that of Phalaenopsis equestris (XP_020579136.1). Their gene expressions were detected in the stems as well as the leaves by qRT-PCR with the expression in the leaves significantly higher than that in the stems. And, the expression of DoSQE1 peaked in August, whereas, that of DoSQE2 in October. Conclusion DoSQE1 and DoSQE2 were successfully cloned for the study that showed differences in their expressions. The information obtained would lead to further investigation on the biosynthesis mechanism and metabolic regulation of sterols in D. officinale.
2020, 35(5): 503-508.
doi: 10.19303/j.issn.1008-0384.2020.05.006
Abstract:
Objective Cymbidium hybrid EST-SSR markers were studied to determine their transferability for applications on the cultivar identification and germplasm utilization of Chinese cymbidium cultivars. Method Genetic diversity of 240 pairs EST-SSR primers in 44 cultivars of Cymbidium goeringii, C. ensifolium, C. sinense and others were analyzed, and their transferability among Chinese cymbidium cultivars examined. Result The rates of transferability were found to be 67.92% for C. goeringii, 66.25% for C. ensifolium, and 71.25% for C. sinense. Among the markers, 17 EST-SSR primer pairs were selected to study the molecular phylogeny of the 44 cultivars. Out of them, 10 primer pairs showed polymorphisms with expanded 52 bands. The bands numbered between 3 to 9 with a range of polymorphism information content between 0.504 and 0.850. These cultivars were clustered into 4 groups, same as concluded by the conventional botanical classification. Conclusion The Cymbidium hybrid EST-SSR markers selected from this study effectively showed the molecular genetic diversity of the various Chinese cymbidium cultivars.
2020, 35(5): 509-518.
doi: 10.19303/j.issn.1008-0384.2020.05.007
Abstract:
Objective Responses of azalea (Rhododendron simsii) seedlings cultivated under the applications of fungi and NPK fertilizer were studied. Method Various fungal additions and NPK fertilizations were applied in cultivating 2-year-old azalea seedlings. The fungal treatments included Rhododendron mycorrhizae (J1), mixture of R. mycorrhizae and exophytic Pinus massoniana (J2), and blank control (J3). The fertilization was varied on the rate of application. Physiology and biochemistry of the azalea seedlings grown under the treatments were determined. Seedling biomass, chlorophyll (Chl) content, and activities of superoxide dismutase (SOD), peroxidase (POD), and catalase (CAT), as well as contents of malondialdehyde (MDA), soluble protein (SP), soluble sugar (SS), auxin (IAA), cytokinin (ZR), gibberellic acid (GA3), and abscisic acid (ABA) of the plants were measured and subjected to a principal component analysis. Results The fungal additions increased the contents of Chla, Chlb, total Chl, SP, IAA, ZR, and GA3 as well as the activities of SOD, POD, and CAT, but reduced the MDA content in the seedlings. The addition, especially J2 treatment, allowed the seedlings to performed well physiologically with merely 1/4 to 1/2 of the normally applied amount of NPK fertilizer. It was speculated that the mycorrhizal symbiosis as observed might be the result of the improved nutrient absorption, photosynthesis, hormone synthesis, protective enzyme activity, stress resistance, and growth of, as well as the reduced membrane lipid peroxidation in the plants. It appeared that all indicators selected for this study were correlated. Conclusion The overall physiological and biochemical indicators on the azalea seedlings cultivated with the fungal applications were better than those of control. In particular, the treatment of J2 not only reduced the NPK fertilization by half (i.e., urea 1.1 g ·plant−1, CaMgP 1 g·plant−1, and KCl 0.7 g KCl·pllant−1) but also elevated the levels of Chl, SOD, SP, IAA, and GA3 on the azalea seedlings.
2020, 35(5): 519-524.
doi: 10.19303/j.issn.1008-0384.2020.05.008
Abstract:
Objective The optimum amount of limbs to be retained on an apple tree pruned to a tall-spindle shape that would result in high-yield of quality fruits was investigated. Method Effects of the amount of saved limbs after pruning on fruit yield and quality of 5–7 years old dwarf apple trees were determined. Result The average fruit yield per apply plant increased, and then declined, with increasing number of limbs retained, within a range, after the pruning. The yield peaked when 25 main branches were saved, while the individual fruit weight maximized when 23–24 limbs remained on a plant. The greatest total soluble solids (TSS) and anthocyanin contents in the apples were found on the trees with 23–25 limbs retained and decreased as the number of the limbs increased. The correlations between the limb retention and those indicators were significant with coefficients ranging between −0.721 and −0.964. Conclusion Taking the yield per plant as well as the individual fruit weight, TSS, and total anthocyanin of apples into consideration, a 5–7 years old dwarf tree could be pruned onto a tall-spindle shape with 24.29 limbs remaining to achieve maximized results.
2020, 35(5): 525-531.
doi: 10.19303/j.issn.1008-0384.2020.05.009
Abstract:
Objective Effects of using a slow-release fertilizer to reduce nitrogen (N) demand on the yield and quality of oolong tea were studied for efficient fertilization at plantations. Method Wuyi rock tea, Huangguanyin, bushes were planted under various fertilization treatments including no N fertilizer (CK1), conventional application (CK2), and a slow-release fertilizer with 10% (T1), 20% (T2), 30% (T3) or 40% (T4) N reduction. Yield of fresh leaves per plant and quality of the oolong tea made were determined. Result Compared with CK1, the use of the slow-release fertilizer increased the organic matters and pH in soil as well as the contents of N and amino acids in leaves, yield, and SPAD of the plants. The leaf yields under CK2, T1 and T2 did not differ significantly. But, in comparison to CK2, T1 resulted in 4.01% higher on soil organic matters, 5.82% lower on pH, 10.11% greater on amino acid content in tea leaves, and 10.11% lower on polyphenols/amino acid ratio; while T2 rendered 3.10% higher on soil organic matters, 2.41% lower on pH, 9.04% greater on amino acid content in tea leaves, and 5.57% lower on polyphenols/amino acid ratio. A principal component analysis on these criteria showed the top two principal components contributed 95.20% of the total. The scores on the components differed significantly with those for T1 to be 4.418 on the top first component and 1.092 on the second component; and those for T2, 2.038 on the first component and 0.731 on the second component. Conclusion By using the slow-release fertilizer to replace 10% or 20% N, both yield and quality of oolong tea were improved.
2020, 35(5): 532-537.
doi: 10.19303/j.issn.1008-0384.2020.05.010
Abstract:
Objective Growth and quality of Ganoderma lucidum cultivated at fields under varied relay cropping methods were evaluated for the planting practice at tea plantations. Method Under the vertical and horizontal cultivation modes of relay cropping, G. lucidum were grown to compare with the conventional greenhouse cultivation. The growth, commercial properties, and quality of the fungi were compared. Result Under the relay cropping, G. lucidum grew to maturity, released spores, and gave commercial appearance similarly to the greenhouse cultivation. However, compared to the conventional planting, the vertical relay cropping method required 25 d longer to reach maturation with a significantly reduced germination rate by 12.8% and the biotransformation rate by 10.48%; while the horizontal method caused a 18 d delay in maturation with significantly declined rates of germination by 14.5% and biotransformation by 4.49%. On the other hand, the contents of polysaccharides, total triterpenes, and amino acids in G. lucidum were with no significant difference with the greenhouse cultivation. The polysaccharide content of the vertical relay cropped G. lucidum was 1.09%, which was a 9.90% higher than that of control; and, that of the horizontal relay cropped G. lucidum was 1.08%, which was a 9.29% higher. The vertical relay cropping produced 1.19% triterpenes in the fruiting body, which was an increase of 11.48% over control; while the horizontal cultivation delivered 1.21% with an increase of 13.55% over control. Conclusion Although relay cropping G. lucidum with tea bushes in a plantation hindered the growth of the fungi with somewhat reduced commercial appeal, it improved the quality of the fungal product.
2020, 35(5): 538-544.
doi: 10.19303/j.issn.1008-0384.2020.05.011
Abstract:
Objective Various fungi with a potential to be used for controlling the soft-rot disease on Fuding taro, Colocasia esculenta L. var. comosus Chang, were investigated. Method Twenty-two fungal strains were isolated from rhizosphere soil and corms of healthy taro plants. Nine of them showing an in vitro antagonistic effect on the disease were selected. Molecular sequencing, morphological observation, physiological and biochemical characterization in the laboratory as well as a field test were conducted on them to screen for applicable candidates. Result Fungal strains under the coded names of CAF-H001 and CAF-L002 exhibited a desirable control effect on taro in the laboratory. The ITS1/ITS4 sequences of the two strains were amplified and compared with NCBI database to show a 100% homogeny of CAF-H001 with Fusarium fujikuroi and of CAF-L002 with Aspergillus tubingensis. CAF-H001 had white mycelia and sickle-shape conidia that grew optimally at pH 9 and 28℃ on starch for carbon and peptone for nitrogen sources. Whereas, CAF-L002 had black mycelia and spherical conidia that preferred pH 8, 32℃, starch, and yeast extract. Conclusion It appeared that CAF-H001, Fusarium fujikuroi and CAF-L002, Aspergillus tubingensis, could potentially be applied for controlling the soft-rot disease on taro.
2020, 35(5): 545-551.
doi: 10.19303/j.issn.1008-0384.2020.05.012
Abstract:
Objective Correlations between the growth, reproduction, and distribution of Leptocybe invasa, an insect that causes galls in plants, and the surrounding temperature were studied to facilitate the monitoring and controlling the spread of the pest wasp. Method Duration and speed of each development state of the wasp were measured by inoculating and feeding the larvae indoor at 19, 22, 25, 28 and 31℃. Graphic, linear, and logistic regression analyses were applied to establish the correlations. Threshold and effective temperatures for the emergences of various stages of the insect were obtained using a linear regression model. Result Temperature was found to significantly affect not only at the stage from egg to pupa, but also the entire development and adult life of the insect. The increasing temperature hastened the insect development process. The graphic linear regression model seemed to more accurately describe their correlation than the other models. In Gannan, Jiangxi, the threshold emergence temperature of the eggs was found to be 10.78℃; that of the larva, 10.29℃; that of the pupa, 14.64℃; the adult survival threshold temperature, 14.73℃; and, the temperature for the development of an entire generation, 12.68℃. The accumulated effective temperature for the eggs was found to be 86.96℃; that for the larva, 588.24℃; that for the pupa, 92.59℃; that for the adult survival, 104.17℃; and, that for the development of an entire generation, 712.34 d·℃. And, the optimum temperature for the egg development, 25.68℃; for the larvae, 25.65℃; for the pupa, 24.58℃; for the adult survival, 26.42℃; and, for the development of an entire generation, 23.84℃ with a range between 12.21℃ and 35.48℃. The model estimated 4.27 generations of L. invasa had taken place between 2017 and 2019 which was in agreement with what was observed in the field. Conclusion Temperature was critical for the development of L. invasa. Understanding the correlation would aid in predicting the development, infestation time and area, and emerging generations of L. invasa for effective control of the pest.
2020, 35(5): 552-559.
doi: 10.19303/j.issn.1008-0384.2020.05.013
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Objective The heating time in a hydrothermal carbonization process used to convert Miscanthus floridulus into biochar was varied to examine the chemical and microstructural differences in the resulting material for potential applications. Method An experiment applying 200℃ hydrothermal carbonization on the perennial grass in a pressurized reaction cauldron for 0, 1.5, 3.0, 6.0, and 9.0 h was conducted. Properties including organic carbon, total nitrogen, total phosphorus, C/N ratio, ash, pH, yield, and loss of elements of the biochar were determined, and microstructure observed under a scanning electron microscope (SEM). Results After the carbonization, the biochar had an organic carbon content ranging from 39.90% to 54.82%, a C/N ratio from 57.90 to 81.22, and a yield from 57.3% to 67.1%. The longer the treatment time, the higher the organic carbon, total nitrogen, C/N ratio, carbon loss, phosphorus loss and ash loss were in the biochar. The total phosphorus, total ash, pH and yield decreased as well. The rate of nitrogen loss peaked after 6 h of carbonization but was significantly lower at 9 h compared with other treatment time. Under SEM, the biochar appeared with numerous starch particles. Prolonged carbonization significantly charred the surface with disorganized, thickened, and stacked tissues. Most of the vascular bundles was damaged, the thin-walled cells blocked, and the edges thickened with clear outlines. The starch granules began to slacken followed by the appearance of many irregular-shaped or ellipsoidal microspheres that coalesced and fused together. Conclusion The hydrothermal carbonization converted M. floridulus into biochar with changed chemistry and microstructure. Prolonged heating decreased the yield, pH, carbon, and phosphorus in the material. A carbonization time longer than 3 h could already significantly alter the properties of the biochar as observed under the experimental conditions.
2020, 35(5): 560-568.
doi: 10.19303/j.issn.1008-0384.2020.05.014
Abstract:
Objective Community diversity and structures of the bacteria in the rhizosphere and endosphere of wild Cymbidium ensifolium were studied to understand the symbiotic relationship between them. Method The high-throughput sequencing method was applied to identify the bacteria in the rhizosphere soil and the root-endosphere of C. ensifolium at locations in Mt. Gushan, Fuzhou where the wild orchids were found. Species diversity and community structures of the spheres were compared. Result Numerous species of bacteria were found in the specimens. The Simpson index in the rhizosphere soil was determined to be of 0.99, and that in the root-endosphere 0.95. The Shannon indices indicated that the rhizosphere was significantly more diverse on species than the root-endosphere. There were 10 phyla of bacteria in the rhizosphere with the dominant ones being Proteobacteria (60.5%), Acidobacteria (20.5%), and Actinobacteria (15.3%). In the root-endosphere, the prevailing phyla were Proteobacteria (75.3%), Acidobacteria (7.3%), and Actinobacteria (14.6%). Among the 10 bacterial genera in the highest abundance, Solibacter and Acidipila existed only in the rhizosphere, while Dyella, Novosphingobium, and Granulicella only in the root-endosphere. The abundance of Acidobacteria Acidobacteriia bacteria in the rhizosphere were significantly higher than those in the root-endosphere. Of the 11 significantly different orders, only Enterobacteriales showed a greater abundance in the root-endosphere than in the rhizosphere. There were 12 genera significantly more abundant in the rhizosphere than in the root-endosphere. Conclusion The significantly different microbial community diversity and structures in the field rhizosphere and root-endosphere of wild C. ensifolium grown at the same area might reflect a highly complex synergism between the environment and the plants.
