Latest ArticlesBacillus subtilis Czk1 is a rhizosphere antagonist with a very broad-spectrum antagonistic, growth promotion and induction of plant resistance. In order to fully utilize organic nutrients in agricultural wastes and promote biological control of soil-borne plant diseases, Czk1 was used as the research object in this study, chicken manure as the base fertilizer, corn straw, mushroom bran and coconut bran compost were used as the raw materials, and the liquid-solid two-phase fermentation process was adopted. The total number of viable bacteria and the number of spores were determined by the dilution plate colony counting method. The formula, process parameters and culture conditions of Czk1 solid fermentation materials were determined by the single factor and orthogonal experiment method. The results showed that the optimal conditions for solid fermentation of Czk1 are raw material was mushroom bran and chicken manure compost with the inoculated weight of Czk1 at 10%, the added amount of soybean powder at 10%, the water content at 40%, the fermentation temperature at 37 ℃ and the turning once every 72 h. Under the conditions, the total number of viable bacteria in Czk1 strain could reach 8.63×108CFU/g. The number of spores was 8.37×108CFU/g. The best fermentation material was corn straw and chicken manure compost, Czk1 inoculation amount of 10%, adding 5% soybean powder, 40% water content, fermentation temperature of 37 ℃, turning once every 72 h, the total number of viable bacteria in Czk1 inoculation strain could reach 6.53×108CFU/g. The number of spores was 5.97×108CFU/g. The total number of viable bacteria and the number of spores of Czk1 strain could reach 8.70×108CFU/g and 6.90×108CFU/g, respectively, when 30% mushroom bran was added. The physical and chemical properties of four fermentation biological fertilizer raw materials were determined, and significant differences were observed in their organic matter content and carbon to nitrogen ratio. Among them, chicken manure had the highest pH, total phosphorus, and total potassium content, while the carbon to nitrogen ratio was the lowest. The total content of nitrogen, phosphorus, and potassium was higher than that of corn straw, coconut bran, and mushroom bran; Corn straw has the highest electrical conductivity and organic matter content as the raw material; Coconut bran has the highest total nitrogen content, while mushroom bran has the highest carbon to nitrogen ratio. The seed germination index of bio-organic fertilizer with different combinations of chicken manure, mushroom bran, corn straw, and coconut bran is greater than 80%. Therefore, high quality bioorganic fertilizer can be prepared from agricultural waste by selecting suitable fermentation production conditions. B. subtilis Czk1 has good development and utilization value.
The effects of different fertilizer combinations on the growth and nutrition of Camellia oleifera were studied to select the fertilizer combination that is conducive to the growth of C. oleifera. Ten-year-old common C. oleifera Cenruan 3 was used as the material. Ten experimental treatments with different N∶P∶K ratio and dosage, and different dosage of organic fertilizer were set. The physiological indexes of fruit traits, leaf traits and nutrition of C. oleifera at different growth stages were measured, and the analysis of variance, multiple comparisons and correlation analysis were performed. The results show that 0.5 kg N∶P∶K (20∶8∶17) +5 kg organic fertilizer+0.25 kg medium elements water-soluble fertilizer (Ca+Mg≥10.0%) had the best growth effect on C. oleifera. This fertilizer combination could effectively increase the fruit size, leaf area, net photosynthetic rate, transpiration rate and contents of nitrogen, phosphorus, potassium, calcium and magnesium in trees, which is conducive to the storage and distribution of tree nutrition. In conclusion, 0.5 kg compound fertilizer N∶P∶K=2∶1∶2 and 5 kg organic fertilizer applied together twice one year in the Spring and Autumn had a better effect on the growth and nutrition of C. oleifera.
To clarify the effects of short-term high temperature stress on the developmental, reproductive characteristics and offspring fitness of Eotetranychus sexmaculatus females, the females were exposed to 33 ℃, 36 ℃, 39 ℃, 42 ℃, 45 ℃ for 1 h, 2 h, 4 h, respectively. The longevity, fecundity, offspring developmental period and sex ratio of E. sexmaculatus females were observed. The results showed that the oviposition period of E. sexmaculatus was prolonged and the fecundity was increased exposed to from 33 ℃ to 42 ℃ for 1 h, 2 h, 4 h and 45 ℃ for 2 h and 4 h. The population growth of E. sexmaculatus was the most favorable exposed to 39 ℃, the oviposition period was the longest exposed to 39 ℃ for 1 h, which was 12.67 d, and the fecundity of single female was the highest, which was 32.65. The intrinsic rate of increase (rm) of E. sexmaculatus was the highest exposed to 39 ℃ for 1 and 4 h, which was 0.29, and the population doubling time was shorter, which was 2.42 d and 2.38 d, respectively. Exposed to short-term high temperature stress, there was no significant effect on the offspring sex ratio of E. sexmaculatus. The survival rate of E. sexmaculatus was decreased, the fecundity was decreased, the longevity was prolonged, and the rm value was decreased exposed to 45 ℃ for 1 h. Therefore, the population development of E. sexmaculatus was inhibited at 45 ℃ high temperature stress for 1 h.
In order to clarify the alleviating effect of heterologous double-root on coffee continuous cropping obstacle, the soil of the continuous cropping obstacle garden of coffee was used to cultivate Caffea liberica, No. 1 and C. canephora, Reyan No. 1 heterologous double-root grafting coffee seedling. The mechanism of heterologous double-root alleviating continuous cropping obstacle was clarified through different root separation ways, and the differences and synergies of heterologous double-root in alleviating continuous cropping obstacle were discussed. Compared with non-rhizosphere soil, the seedling quality index and plant biomass of heterologous double-root coffee or homologous double-root coffee decreased significantly after culturing in rhizosphere soil. After non-rhizosphere soil culture, there were no significant differences in the seedling quality index or plant biomass between heterologous double-root coffee and homologous double-root coffee. The seedling quality index, root biomass of C. liberica and C. canephora, and total plant biomass of heterologous double-root coffee were significantly higher than those of homogenous double-root coffee after rhizosphere soil culture. Continuous cropping obstacle inhibited the growth of coffee, but had more effect on homologous double-root coffee. Heterogenous double-root coffee alleviated the growth obstacle of continuous-cropping coffee by C. liberica roots. The seedlings quality of the heterologous double-root coffee separated root by nylon net was better than that of root undivided or separated root by double pot under continuous cropping, and the root growth of C. canephora was the best in nylon net separation. Root allelochemicals of C. liberica promoted the root growth of C. canephora. There was no significant difference in the seedlings quality of heterologous double-root coffee between root undivided and separated root by double pot, and the C. liberica root growth of root undivided was worse than that of double pot separation. The root growth of C. canephora inhibited the root growth of C. liberica when the heterologous double-root were in contact with each other, but this inhibition was not related to the allelopathic substances in the C. canephora rhizosphere. The root growth of C. liberica had no significant difference in nylon net separation and double pot separation. There was no effect on the root growth of C. liberica with or without the allelopathic substances. of C. canephora. The root system of C. liberica alleviated the continuous cropping obstacle by reducing the inhibition of allelopathic environment and promoting the root growth of C. canephora by its allelopathic substances. The results would provide a theoretical basis for the application of heterologous double-root grafting in the field.
In this study, the rhizosphere soil of jasmine was used as the material under the condition of artificial greenhouse to analyze and compare the effects of two fungicides (fluazinam and tebuconazole) on soil physical and chemical properties, soil enzyme activities in addition to carbon source metabolic diversity of soil microbial community. The indexes of soil physical and chemical properties were different under the application of the two fungicides of different concentration. The pH value and organic matter content of soil decreased by 14.8% and 18.8%, respectively, after application of 50% fluazinam. The content of organic matter increased by 76.8% after treatment with 50% tebuconazole. 50% of tebuconazole had the most significant effect on total nitrogen, available phosphorus and available potassium, and the highest increase of total nitrogen was 77.8%. The maximum available phosphorus increased by 1.3 times while the content of available potassium increased by 2.1 times. The effects of fungicides on the activities of sucrase, urease and acid phosphatase in jasmine rhizosphere soil were significant. The sucrase activity was significantly decreased by 92.8% after treated with 50% fluazinam. The urease activity decreased significantly after spraying 50% tebuconazole, which was 41.9% lower than that before spraying. At the same time, the acid phosphatase activity showed increasing trends after treated with fungicides. To compare the carbon source metabolic diversity of soil microbial community after application of the fungicides found that the value of average well color development (AWCD) in CK was the lowest. After the treatment of the two fungicides, AWCD decreased compared with that before spraying, among which the inhibitory effect of tebuconazole on AWCD was the most significant. In general, the Shannon diversity index (H) and evenness index (U) of soil microorganisms showed a decreasing trend with fungicide treatment. However, there was no significant difference in the dominance index (D) among all treatments. Soil microbial community had a certain inhibitory effect on the metabolic diversity of six kinds of carbon sources after fungicides application. In addition, principal component analysis of soil microbial community carbon source metabolic diversity revealed that amino acids and carbohydrates had similar utilization rates. In addition, polymers and carboxylic acids were similar. This study analyzed and compared the effects of fluazinam and tebuconazole on the microbial characteristics and carbon source metabolic diversity in jasmine rhizosphere soil, and the results would provide a scientific basis for evaluating the ecological function in rhizosphere soil microorganisms of jasmines under the influence of two fungicides.
Five sweet potato cultivars with significant differences in germination, Jixu 23, Yanshu 25, Red Banana, Taizhong No. 6 and Xinxiang, were used as the test materials. During the storage period, samples were taken regularly to analyze the changes of endogenous hormones and carbohydrate metabolism in the storage roots. Storage roots after storage were planted for seedlings in small arch sheds and investigated. The results showed that Jixu 23, Yanshu 25 and Red Banana germinated earlier, and the number of seedlings picked was significantly more than that of Taizhong 6 and Xinxiang. At the end of storage and before seeding, the starch content and amylopectin content of storage roots in Jixu 23, Yanshu 25 and Red Banana were significantly higher than those of Taizhong No. 6 and Xinxiang, Jixu 23, Yanshu 25 and Red Banana. Higher content of amylopectin and amylopectin was mainly due to the smaller decrease during storage. The total amylase and α-amylase activity of storage roots in Jixu 23, Yanshu 25 and Red Banana were significantly higher than that of Taizhong No. 6 and Xinxiang, and the α-amylase activity of storage roots in Jixu 23, Yanshu 25 and Red Banana were higher than that of Jixu 23, Yanshu 25 and Red Banana. This is mainly due to the larger increase during storage. At the end of storage and before seeding, compared with Taizhong No. 6 and Xinxiang, Jixu 23, Yanshu 25 and Red Banana had higher GA content, lower IAA content, and higher GA/ABA and ZR/IAA of storage roots. That is, at the end of storage and before seeding, high starch and amylopectin content, high α-amylase activity, high endogenous GA content, and low IAA content in storage roots are physiological indicators of good germination.
In the current study, one newly recorded genera of wild orchids, Neuwiedia Blume, as well as five newly recorded species, including Goodyera brachystegia Hand. -Mazz, Neuwiedia zollingeri var. singapureana (Baker) E. F. de Vogel, Odontochilus drymoglossifolius (Hayata) T. Yukawa, O. saprophyticus (Aver.) Ormerod and O. yakushimensis (Yamam.) T. Yukawa in Fujian province were illustrated. The voucher specimens of the plants are preserved in the Herbarium of Fujian Normal University (FNU). The discovery of the newly recorded orchids has great significance for further studies on the diversity and conservation of Orchidaceae in Fujian, China.
In recent field survey and specimen examination, eight species of pteridophytes belonging to seven genera in five families are reported as new records in Fujian province, Gymnocarpium oyamense (Baker) Ching, Pronephrium parishii (Beddome) Holttum, Athyrium drepanopterum (Kunze) A. Braun ex Milde, Diplazium okinawaensis Tagawa, D. hainanense Ching, Hymenasplenium excisum (C. Presl) S. Lindsay, Asplenium ensiforme Wallich ex Hooker & Greville and Microsorum membranaceum (D. Don) Ching. Among them, G. oyamense is a newly recorded genus in Fujian province, and P. parishii, A. drepanopterum, D. okinawaensis, D. hainanense and M. membranaceum are newly recorded species in East China.
A time-saving, efficient and environmentally friendly method for the preparation of soluble dietary fiber (SDF) from coffee peel with ultrasound-assisted low eutectic solvents (UAE-DESs) was established for the first time, and its process parameters were optimized by single-factor test and response surface test to further explore a new green method for the preparation of soluble dietary fiber from coffee peel. Eight choline chloride-based deep eutectic solvents were prepared as extraction solvents by the heating method and compared with the conventional water extraction method. The results showed that the deep eutectic solvent system with a 1∶2 molar ratio of choline chloride to urea prepared the highest yield of soluble dietary fiber from coffee peel at 10.10%±0.11%, which was significantly higher than that of the conventional water extraction method at 6.50%±0.22%. The effects of DES composition (molar ratio, water content, liquid-to-solid ratio) and ultrasonic treatment (ultrasonic power, ultrasonic time) on the yield of soluble dietary fiber from coffee peel were investigated by single-factor experiments. The response surface methodology (RSM) combined with Box-Behnken design (BBD) was used to optimize the soluble dietary fiber yield and investigate the effects of deep eutectic solvent water content, liquid-solid ratio, ultrasonic power and ultrasonic time on the yield of soluble dietary fiber. Based on the optimization results of RSM, the optimal preparation conditions were determined as follows: water content of deep eutectic solvent 39.91%, liquid-solid ratio 32.37 mL/g, ultrasonic power 305.20 W, and ultrasonic time 33.80 min. Under this condition, the maximum soluble dietary fiber yield of coffee peel was 10.74%±0.14%, which was close to the predicted soluble dietary fiber value of 10.80%. Therefore, as an efficient and non-polluting green solvent, deep eutectic solvent can be used for the preparation of soluble dietary fiber from coffee peel. The results of this study would provide new ideas and theoretical references for the preparation of soluble dietary fiber from coffee peel, and have potential applications in the value-added utilization of coffee by-products, the production of new high value-added products and the development of natural functional foods.
Rubber particles are important components in latex, and have important effects on latex stability, rubber biosynthesis and processing properties. However, the difference of rubber particle size and distribution among different germplasms and the annual changes have not been systematically studied. In this study, 486 wild and cultivated Hevea germplasm planted in National Rubber Germplasm Respository were selected, and the latex were collected monthly during the tapping period from 2020 to 2021. The average diameter (Da), intermediate diameter (Di), intermediate diameter/average diameter (Di/Da), particle size≤0.259 μm frequency and particle size≤0.197 μm frequency of rubber particles were analyzed and studied. Da varied from 0.313 μm to 0.439 μm, and the coefficient of variation (CV) was 0.008-0.206. Di varied 0.209-0.366 μm, and the CV was 0.009-0.235. Di/Da varied 58.3%-84.9%, and the CV was 0.015-0.123. particle size≤0.259 μm frequency varied 31.1%-61.8%, and the CV was 0.013-0.322; particle size≤0.197 μm frequency varied 17.6%-46.4%, and the CV was 0.018-0.588. The five indexes showed significant differences among germplasm, which were suitable to be latex characteristic index. The correlation analysis of the five indexes showed that the correlation coefficient of Di and Da was 0.781; The correlation coefficient of particle size≤0.259 μm frequency and particle size≤0.197 μm frequency was 0.976; The correlation between Di and Di/Da was higher than that of Da, and the correlation coefficient reached 0.814. Di was also more correlated with particle size≤0.259 μm frequency and particle size≤0.197 μm frequency than Da, and the correlation coefficient reached 0.520 and 0.632, indicating that Di had a stronger statistical significance. Annual changes of Da, Di and Di/Da showed some difference. Da in June, July, August, October and December was not significant, and September and November were lower than other months. Di was not significantly different in June, July, August, September, November and December, and just a little lower in October. Di/Da had no significant difference in June, August and September, increased in November and December, but declined obviously in July and October. Da, Di, Di/Da, ≤0.259 μm frequency, ≤0.197 μm frequency in each month were all significantly correlated with the annual average. However, correlation coefficient were higher between alternate monthly measurements (June, August, October; July, September, November; August, October, December) and the annual average, reaching more than 0.850. That can be used for future rubber particle size testing.