Horticulturae
Low temperature freezing damage is the main disaster of late maturing citrus in Nanchong. Based on frozen injury experiments and historical disaster data from the agricultural department, combined with the hourly temperature situation of the National Meteorological Monitoring Station, the threshold of low-temperature freezing injury indicators was studied using probability regression and information diffusion theory methods during the winter period under the conditions of no cloud or less cloud sky, the daily temperature range ≥8℃, and the minimum temperature ≤3℃. The results showed that the linear regression relationship between the meteorological temperature established for the two experimental orchards and the measured temperature was statistically tested. When the meteorological temperature was 1.7℃ in Xichong and 2.6℃ in Jialing, the measured temperature of the orchards would reach -2℃, and frost damage began to occur; Based on the current refined weather prediction capability, a composite index threshold system based on the maximum duration (hours), total duration (hours), and total days of low-temperature freezing damage days during a sliding two week period was established. Four frozen damage samples were selected for testing, and the results showed that the frost damage index rating was in good agreement with the measured frost damage level, which had good practical application value.
In order to investigate the effects of different wavelengths of LEDs light sources on the growth of tartary buckwheat sprouts, red (R), blue (B) and green (G) LEDs were used to culture the sprouts, with the darkness as a control. The indicators including morphological growth, bioactive matter accumulation, key gene expression involved in flavonoid synthesis, and antioxidant activity were determined, respectively. The results showed that the hypocotyls of tartary buckwheat sprouts under B were deep red and the hypocotyl elongation was strongly inhibited. The accumulation of anthocyanins, total flavonoids and total phenols under B were the highest, which were 7.18, 2.96 and 2.49 times as that of D, respectively. The hypocotyl of tartary buckwheat sprouts under R showed a light pink color. The accumulation of the above three bioactive substances under R was also significantly higher than that of the control, which was 2.56, 1.68 and 1.40 times, respectively. The hypocotyl elongation of the sprouts under G was similar to that of R, but the appearance was transparent and white. The accumulation of bioactive matters under G was not significantly different from that of the control. Both B and R strongly induced the expression of key genes involved in flavonoid biosynthesis pathway, and significantly increased the antioxidant activity of the hypocotyls of tartary buckwheat sprouts. In conclusion, red and blue LEDs could significantly affect the morphological growth of tartary buckwheat sprouts, and increase the accumulation of bioactive substances as well as the antioxidant capacity. Meanwhile B treatment was recommended due to the best performance.
The major objective of the present study is to show application potential of Helleborus in China and to accelerate development and utilization of Helleborus in the fields of medicine, manufacturing and landscaping. The biological characteristics, habits and cultivation techniques of the genus were reviewed, and the chemical components, medicinal effects, origin of names, ornamental characteristics and garden application were discussed. It was found that the subjects had significant medicinal, cultural, and ornamental value. It was pointed out that there were insufficient efforts in botany basic research, medicinal plant development, and new variety cultivation in current work. At the same time, countermeasures and suggestions were proposed accordingly.
In order to master the quality and safety of edible fungi, the levels of 62 kinds of pesticide residues in edible fungi sold in Beijing from 2021 to 2022 were screened, the pesticide residues of insecticides and fungicides in 6 common edible fungi were evaluated by food safety index method, and the risk of chronic and acute dietary intake of 19 pesticides were also evaluated. The results showed that the IFS values of 15 insecticides and 4 fungicides detected in edible fungi and the average food safety index values of 6 edible fungi were all less than 100. The pesticide residues detected had little influence on the edible fungi, and the six edible fungi were in a good state of safety, the risk of chronic dietary intake and the risk of acute dietary intake of 19 detected pesticide residues in edible fungi were both lower than 100%, and the risk of both chronic and acute dietary intake were lower. However, the risk values of dietary intakes of two pesticides, cyromazine and emamectin benzoate, were relatively high among the 19 pesticides detected. Therefore, it is necessary to strengthen the supervision of the use of cyromazine and emamectin benzoate in edible fungi to ensure the quality and safety of edible fungi products.
The paper aims to select the most suitable amount of the mulch of the stem and leaf residue from Alpinia zerumbet for weed control and lettuce growth. The stems and leaves of A. zerumbet rich in allelopathic substances were selected as materials. In this research, the growth of weeds, lettuce, and changes in soil physicochemical properties were evaluated by covering different amounts of mulch of the stem and leaf residue from A. zerumbet between rows in lettuce fields according to the theory of covering cultivation and the principle of allelopathic grass control. The results showed that with the increase of the stem and leaf residue mulching amount from A. zerumbet, the inhibition on weeds in lettuce fields was enhanced. Among them, compared with the control group, the species, quantity, and diversity of weeds in the lettuce field decreased, and the weed biomass (fresh weight and dry weight) decreased by 87.93% and 90.54%, respectively after mulching with 1200 g/m2 of the stem and leaf residue from A. zerumbet. Meanwhile, lettuce had the highest chlorophyll content and average fresh weight per plant, with the best quality. In addition, the content of soil organic matter, total nitrogen, available nitrogen, and available phosphorus increased. When the coverage was greater than 1600 g/m2, the soil physical and chemical properties showed different changing trends, and the growth of lettuce was inhibited, but the overall quality was improved. Overall, in the production of winter and spring lettuce in Yibin area of Sichuan Province, the use of 1200 g/m2 of the mulch of the stem and leaf residue from A. zerumbet can effectively inhibit the growth of weeds in the field, improve the soil environment, and promote the growth and development of lettuce.
The paper aims to explore the effects of different transplanting dates on pepper's yield, quality and photosynthetic characteristics in Guizhou. Seven transplanting dates were set with the main pepper cultivars ‘Layan No.1’, ‘Zunyi Chaotianjiao’ and ‘Xianjiao 269’ as test materials, the characteristics of the yield structure under different transplanting date were compared. And the relationship between meteorological factors including temperature and precipitation and the growing stage, photosynthetic characteristics, yield structure, quality were also analyzed. The results showed that the average temperature in the growth stage of pepper had the greatest influence on the yield, and the duration of each growth stage was related to meteorological factors. Earlier sowing could prolong the growth stage, increase the diurnal temperature range after pepper flowering stage, and speed up the net photosynthetic rate. The temperature and precipitation mainly affected the plant height, stem diameter, vitamin C, capsaicin, dihydrocapsaicin and other indicators. With the delay of transplanting, the yield of pepper increased first and then decreased gradually, timely and early sowing is beneficial to the increase of pepper yield.
The paper aims to study the effects of different ratios of 6-BA and NAA on sweet potato callus differentiation, subculture multiplication and growth of test-tube seedlings after transplanting, and to establish an efficient system for virus-free in vitro tip meristem culture and rapid propagation technology. Four widely cultivated sweet potato cultivars, ‘Yanshu 25’, ‘Pushu 32’, ‘Longshu 9’ and ‘Shangshu 19’, were used for this experiment. Six 6-BA/NAA concentration ratios were added to MS medium to prepare the induction differentiation medium and the subculture multiplication medium. The callus differentiation rate of tip meristem, seedling formation rate, diameter of callus tissue and number of leaves were investigated, and the differences in survival rate of test-tube plantlets after transplanting, number of leaves, plant height and basal stem thickness were investigated as well to explore the optimal formulations for the callus differentiation, subculture multiplication, and the growth of test-tube seedlings after transplanting. The highest callus differentiation rate of ‘Yanshu 25’ and ‘Pushu 32’ was obtained at A4 treatment (1.5 mg/L 6-BA+ 0.2 mg/L NAA), and the highest callus differentiation rate of ‘Longshu 9’ and ‘Shangshu 19’ was obtained at A3 treatment (1.5 mg/L 6-BA+ 0.2 mg/L NAA). ‘Yanshu 25’ showed better growth in subculture multiplication culture, had a higher survival rate and grew faster in B4 treatment (0.5 mg/L 6-BA+ 0.4 mg/L NAA) than others. The optimal medium for ‘Pushu 32’, ‘Longshu 9’ and ‘Shangshu 19’ was determined as B3 treatment (0.5 mg/L 6-BA+ 0.2 mg/L NAA), with the best growth in subculture multiplication culture, the highest survival rate and the fastest growth after transplanting. In the process of sweet potato callus differentiation and rapid propagation, there were significant differences in the appropriate proportion of 6-BA and NAA for different sweet potato cultivars, and the cultivars characteristics should be fully considered in the actual production.
The research was conducted to reveal the leaf anatomical structure characteristics and photosynthetic physiological response mechanism of different Toona sinensis clones under natural high temperature and drought stress, and provide reference for T. sinensis cultivation and germplasm resource utilization. Using 5 2-year-old T. sinensis clones seedling as the research objects, including ‘XC34-2’、‘XC12-10’、‘XC9-9’、‘XC18-4’、‘XC6-6’, and 2 native varieties as reference, including ‘Black oil toona’ and ‘Red oil toona’. Leaf anatomical structure, chlorophyll contents and chlorophyll fluorescence parameters characteristics under high temperature and drought stress were measured, the single factor analysis of variance were used to compare the differences between all indexes among the clones. The results showed that the middle vein of the five clones were thinner than those of ‘Black oil toona’ and ‘Red oil toona’, and other anatomical structures were thicker than those of ‘Black oil toona’ and ‘Red oil toona’, except for the spongy tissue, among which ‘XC18-4’ had the thickest leaves and the most developed palisade tissue and spongy tissue. The thickest cuticle (2.01 μm) of ‘XC34-2’ was 1.63 times that of the thinnest cuticle of ‘Red oil toona’. Seven clones subjected to the extremely different degree of photoinhibition in the same dry and hot environment, with Fv/Fm varying from 0.67 to 0.79. High temperature and drought stress affected the distribution of excitation energy absorbed by PS Ⅱ in T. sinensis clones. ‘XC34-2’ had higher Y(Ⅱ) and lower Y(NO) and Y(NPQ), and ‘Red oil toona’ was roughly the opposite. In addition, different clones took different photoprotection strategies under high temperature and drought. The excess excitation energy in ‘XC9-9’ and ‘XC18-4’ was mainly contributed by the closed PSⅡ reaction center, and the excess excitation energy shifted to regulatory energy dissipation [Y(NPQ)], while the non-regulatory energy dissipation [Y(NO)] in ‘Red oil toona’ and ‘XC6-6’ played an equally important role in the unworked energy. Four typical indicators were screened by principal component analysis, including cuticle thickness, chlorophyll a/b ratio, maximum photochemical quantum yield and palisade tissue thickness. According to the results of the average subordination function scores, the high temperature and drought tolerance of 5 T. sinensis clones was stronger than that of the two native varieties. With strong capable of dry-hot burn resistance, water regulation and absorption, transformation and utilization of light energy, ‘XC18-4’ got the highest average score of subordination function (0.929), and was classified as high resistance clone according to the 5-level scoring method, followed by ‘XC34-2’ (0.747), belonging to a resistance clone under hot and drought stress. ‘Red oil toona’ (0.219) was more sensitive to high temperature and drought stress.
A pot experiment was carried out to investigate the effects of different ratios of NH4+-N and NO3--N on the yield and quality of Sonchus arvensis. Vermiculite was used as cultivation substrate, and total nitrogen concentration was 15 mmol/L. Five ratios of NH4+-N and NO3--N (100/0, 75/25, 50/50, 25/75, 0/100) were designed in the experiment. The 40-day seedlings were harvested, then indexes related to the yield and quality were determined. The results showed that the S. arvensis preferred nitrate, the yield increased along with the increase of NO3--N content, and the yield of plant supplied with only NH4+-N nutrition solution was the lowest. There was no significant difference in yield between 50/50 treatment and 25/75 treatment, but the leaf area, total nitrogen content and total phosphorus content in shoots of 50/50 treatment were 1.21, 1.15 and 1.47 times of 25/75 treatment, respectively. Moreover, the nitrate and Vc contents of 50/50 treatment was 2.23 times and 1.12 times of 25/75 treatment, respectively. However, proper combination NH4+-N with NO3--N could significantly reduce the nitrate content to the level of raw food, and increased the chlorophyll content. The research suggested that 50/50 treatment was better for yield and quality.
To investigate the effects of combined application of bio-organic fertilizer with reduced chemical fertilizer on growth, yield and quality of Brassica campestris ssp. chinensis var. rosularis, two fertilizer types F1 (N-P2O5-K2O=15-15-15), F2 (N-P2O5-K2O=26-9-9) and 7 application amounts, N1 (pure compound fertilizer 525 kg/hm2), N2 (F reduced by 10%+ bio-organic fertilizer 400 kg/hm2), N3 (F reduced by 10%+ bio-organic fertilizer 600 kg/hm2), N4 (F reduced by 10%+ bio-organic fertilizer 750 kg/hm2), N5 (F reduced by 20%+ bio-organic fertilizer 400 kg/hm2), N6 (F reduced by 20%+ bio-organic fertilizer 600 kg/hm2), N7 (F reduced by 20%+ bio-organic fertilizer 750 kg/hm2) were set up in the experiment. And no fertilization (CK) was also set as the blank control. The agronomic characters, yield, mineral elements and quality characters of B. campestris ssp. chinensis var. rosularis were investigated and analyzed according to the two factors of fertilizer type and fertilizer method. The results were as follows. (1) The interaction between the type of fertilizer and the application amounts had extremely significant effects on most agronomic traits and plant weight (P<0.01). Under different fertilizer treatments, the petiole length, petiole width, leaf weight, petiole weight and weight per plant were all showed as F2>F1. The weight per plant was significantly different between the two treatments (P<0.05). The combination of bio-organic fertilizer with reduced chemical fertilizer F2 were more conducive to the growth and yield increase of B. campestris ssp. chinensis var. rosularis. Under F1 and F2 treatments, the weight per plant was significantly correlated with the degree of development, leaf weight and petiole weight, but there was no correlation between plant weight and petiole thickness. Compared with N1, chemical fertilizer reduced by 10% and 20% combined with rational bio-organic fertilizer didn’t affect the growth of B. campestris ssp. chinensis var. rosularis, and could promote their growth to a certain extent. The maximum increase of weight per plant was 15.24%. (2) Compared with N1, chemical fertilizer reduced by 10% and 20% combined with rational bio-organic fertilizer didn’t affect the content of mineral elements in the edible part of B. campestris ssp. chinensis var. rosularis, and had beneficial effect on the accumulation of mineral elements. However, when the fertilizer were reduced too much, the activation ability of bio-organic fertilizer on soil elements such as P, Mg, K, Ca and other elements would be reduced by different degrees. (3) The type of fertilizer had extremely significant effect on the nitrate nitrogen content of B. campestris ssp. chinensis var. rosularis, and the interaction between the type of fertilizer and the application amounts had extremely significant effect on the coarse fiber of B. campestris ssp. chinensis var. rosularis (P<0.01). The combination of rational bio-organic fertilizer with reduced chemical fertilizer could increase the content of soluble sugar, soluble protein and vitamin C, and reduce the nitrate nitrogen content. Under different fertilizer treatments, the contents of soluble sugar, vitamin C and soluble protein of B. campestris ssp. chinensis var. rosularis were all showed as F1>F2, while the content of coarse fiber, total nitrogen and nitrate nitrogen were all showed as F2>F1, and the contents of vitamin C and soluble protein were significantly different between the two treatments (P<0.01). The combination of bio-organic fertilizer with reduced chemical fertilizer F1 were more conducive to improve the quality of B. campestris ssp. chinensis var. rosularis. The combination of rational bio-organic fertilizer with reduced chemical fertilizer could not only promote the growth, increase the yield, but also improve the quality of B. campestris ssp. chinensis var. rosularis. Based on yield and quality factors, F1N6 and F2N6 could be used as suitable fertilization methods under the experimental conditions.
This study investigates the effects of combined application of nitrogen, phosphorus, and potassium on the growth of Amorphophallus konjac in southern Shaanxi region, aiming to provide a scientific fertilization reference for A. konjac. Using the variety ‘Anmo 128’ as the experimental material, the ‘3414’ fertilization scheme was employed to examine variations in emergence rate, incidence rate, yield, and nutrient utilization efficiency of A. konjac under different levels of nitrogen, phosphorus, and potassium combined application. The experimental results indicated that with increasing application rates of nitrogen, phosphorus, and potassium, the marginal productivities of nitrogen fertilizer, phosphorus fertilizer, and potassium fertilizer gradually decreased. Additionally, both fertilizer agronomic efficiency and marginal productivity followed the order: phosphorus (P)> potassium (K)> nitrogen (N). Considering comprehensive indicators, the fertilization ratio of N1P1K2 (127.5 kg/hm2 N+ 54 kg/hm2 P2O5+ 135 kg/hm2 K2O) demonstrates the most desirable outcomes and is most suitable for local promotion.
In order to select the excellent small-fruit watermelon varieties suitable for the facility cultivation in Jiangsu Province, the quality analysis and comprehensive evaluation of 10 different varieties of small-fruit watermelon were carried out in spring. According to the tasting criteria, watermelons were scored by the tasting personnel after tasting, and the appearance quality, internal nutrition and economic characteristics of watermelons were measured and recorded in turn. Principal component analysis was used to analyze 18 indicators including tasting scores, and the comprehensive scores and final rankings of 10 watermelon varieties were obtained. Judging from the tasting results, ‘Sumeng 107-446’ had the highest score and the best performance. In terms of fruit economic characteristics, ‘Sumeng 108-020’ showed the largest single fruit weight and transverse diameter, and ‘Early Spring Ruby’ had the topmost fruit longitudinal diameter, skin thickness and fruit shape index, which were significantly different from other watermelon varieties. In terms of internal quality of soluble solids, ‘Sumeng 107-446’ exhibited the supreme content of central and marginal soluble solids. In terms of other intrinsic quality indicators, ‘Early Spring Ruby’ had the top sucrose content, ‘Sumeng 111-034’ had the upmost citric acid content, and ‘Sumeng 107-409’ showed the highest shikimic acid content. Principal component analysis was utilized to analyze 18 indicators and extract 5 principal components. The cumulative contribution rate of the 5 principal components was 89.7%, which could explain 89.7% of the original data information. The overall quality scores of 10 small fruit watermelons in the test were ‘Sumeng 107-409’> ‘Sumeng 111-032’> ‘Sumeng 111-034’> ‘Sumeng 108-020’> ‘Early Spring Carbuncle’> ‘Sumeng 107-446’> ‘Sumeng No.7’> ‘Sumeng No.10’> ‘Sumeng 107-462’> ‘Sumeng 108-019’.
This study utilized the fruit appearance indicators and effective nutritional composition indicators of Xinjiang Elaeagnus moorcroftii, combined with principal component analysis and cluster analysis to comprehensively evaluate the fruit quality, aiming to provide a theoretical basis for the further development and utilization of Xinjiang E. moorcroftii. The results showed that there were significant differences in fruit appearance quality of different varieties of E. moorcroftii; the comprehensive evaluation results were ‘Hongling’ (3#)> ‘Hongyu’ (8#)> ‘Jinsha’ (2#)> ‘Jinhuanghou2’ (26#)> ‘Bachu 1’ (5#)> ‘Jinhuanghou’ (6#)> ‘Baishatian’ (7#)> ‘Yafeng’ (1#)> ‘Hongling2’ (33#) by the principal component analysis, and 3#, 8#, and 2# could be used for breeding, promotion, and development and utilization. The 9 varieties of E. moorcroftii were divided into three categories by the cluster analysis. The first category was 3#, which was mainly characterized by high solid acid ratio, tannin and total phenol, low protein and crude fiber, and could be used for making cakes, high-grade fruit juices and drinks. The second category was 2# and 8#, which were mainly characterized by high edible rate, high content of total flavonoids and proanthocyanidins, tannins and total phenols were also higher than the average value, and could be used for deep processing and extraction of effective functional nutrients for health care and medical treatment. Other varieties belonged to the third category, with average indicators, could be eaten and processed fresh, and could also be used as ecological forests.
The study aims at solving the problem of idle mulberry land in winter and constructing mulberry-Morchella intercropping mode in hilly region of Northeast Sichuan. Based on Tillage Science, technologies of Morchella field cultivation and mulberry standardized cultivation were combined to cultivate Morchella in the wide row land of mulberry cultivation. Moreover, the study integrated the practical cultivation technologies of “medium flat sheds cover the small arched ones, flat shed shading, arch shed warming and moisturizing, and wide-row winter fallow land planting Morchella”. The demonstration results of three consecutive years of intercropping Morchella in mulberry fields showed that the average fresh Morchella yield was 0.23 kg/m2 per year, and increased the new profit by 14.55 yuan/m2 per year. The mulberry-Morchella intercropping technology can effectively improve the comprehensive benefits of mulberry fields.
This experiment analyzed the effects of the coupling of different nitrogen, phosphorus and potassium content ratios and the substrate relative water content on the growth of banana and papaya seedlings, to provide a theoretical basis for the conservation-oriented and precision seedling cultivation. Heeling-in seedlings of ‘Brazil’ banana and ‘Zihui’ papaya were used as experimental materials. Twelve interactive combination treatments (T1-T12) was carried out from four levels of nitrogen, phosphorus and potassium content ratio and three levels of the substrate relative water content by two-factor randomized block design method, and the traditional irrigation and fertilization treatment was used as control (CK). Effects of different treatments on plant height, stem diameter, leaf number, leaf SPAD value, leaf area, shoot dry weight, total root length, root surface area, average root diameter and root tip number were studied, and shoot growth indicators were analyzed by PCA comprehensive evaluation. In the experiment on banana seedlings, T6 treatment had the most obvious effect on plant height, leaf area, shoot dry weight, total root length, root surface area and root average diameter. T1 treatment had the largest stem diameter. The leaf number was the largest in T1, T5 and T6 treatments, which were 7.60 leaves. T5 treatment had the highest leaf SPAD value. T7 treatment had the largest root tip number. The order of PCA comprehensive evaluation scores of shoot growth indicators was T6> T5> T1> T2> T10> T3> T9> T7> T11> T12> T4> T8> CK. In the experiment on papaya seedlings, T10 treatment had the most significant effect on plant height, leaf area, leaf number and shoot dry weight. The leaf number and shoot dry weight in T9 treatment were consistent with T10 treatment, and the total root length, root surface area and root tip number were most significantly increased. The leaf SPAD value and the average root diameter were largest in T11 and T2 treatments, respectively. The order of PCA comprehensive evaluation scores of shoot growth indicators was T10> T9> T1> T11> T6> T3> T2> T5> T7> CK> T12> T8> T4. The optimum ratio of nitrogen, phosphorus and potassium content for cultivating seedlings of banana and papaya was 20:10:20, and the optimum substrate relative water content was 80% and 70%, respectively.
In order to explore the ecological adaptability and application potential of lavandin (Lavandula × intermedia) in Fuyang area, six introduced varieties of lavandin were investigated and analyzed in the third year of planting, including growth indicators such as plant height, crown width, number of flower branches, ornamental indicators such as leaf color, flower color, flowering period, and economic indicators such as essential oil content, composition, and unit yield. The results showed that all varieties could grow normally in Fuyang area, and the plant height of ‘Mentha’ was the highest among the six varieties, reaching 81.30 cm; ‘Sumian’ had the largest crown diameter, reaching 114.25 cm; and ‘Nizza’ showed the largest amount of flowers, with a dry weight of 252.63 g/plant. Besides, deep calyx and corolla colors were observed in ‘Arabian Nights’ with the earliest flowering and the longest ornamental period. According to economic indicators, ‘Arabian Nights’ had the highest extraction rate of essential oil, reaching 5.34%, and ‘Nizza’ had the highest yield of essential oil, reaching 9.22 g/plant. Gas chromatography-mass spectrometry (GC-MS) analysis showed that the content of linalool and linalyl acetate in the essential oil of variety ‘Nizza’ was the highest and the quality was significantly superior to other varieties. In summary, among the six lavandin varieties, ‘Arabian Nights’ is most suitable for ornamental cultivation, and ‘Nizza’ is the most suitable variety for essential oil extraction cultivation in Fuyang area.
The effects of different chemical fertilizer reduction combined with organic fertilizer and biological agents on tomato yield, soil microbial and enzyme activities were studied to provide scientific basis for the feasibility of chemical fertilizer reduction combined with organic fertilizer and biological agents and the reduction of fertilizer and efficiency in tomato planting. Six treatments were set up in the experiment, which were CK: blank control (no fertilization); CF: single application of chemical fertilizer; RF1: 20% reduction of chemical fertilizer combined with 20% organic fertilizer; RF2: 40% reduction of chemical fertilizer combined with 40% application of organic fertilizer; RFM1: chemical fertilizer reduction 20% with organic fertilizer 20% + biological agent; RFM2: 40% chemical fertilizer reduction combined with 40% organic fertilizer + biological agent. The results showed that the number of bacteria in tomato rhizosphere soil increased by 53.05%-134.15%, the number of actinomycetes increased by 13.94%-26.55%, and the number of fungi decreased by 20.32%-37.92%, and increased with the increase of organic fertilizer application. The application of biological agents corresponding to the reduction of chemical fertilizer significantly increased the values of soil bacteria/fungi and actinomycetes/fungi. The activities of urease, sucrase and catalase increased with the increase of organic fertilizer application. The reduction of chemical fertilizer treatment corresponding to the increase of biological agent treatment significantly reduced the organic acid content of tomato, and increased the content of soluble solids, Vc and lycopene. The yield of RF1, RF2, RFM1 and RFM2 increased by 4.40%, 6.55%, 8.13% and 0.81 % compared with CF. The fruit number per plant, fruit weight and yield of RFM1 were higher. In summary, the combined application of organic fertilizer and biological agents could change soil enzyme activity and effective nutrient content by improving the number and structure of rhizosphere soil microbial communities, optimize the rhizosphere environment, promote plant growth and development, and achieve the purpose of increasing yield and improving quality. Considering the number and structure of soil microorganisms, enzyme activity, yield and quality, it is more suitable to reduce the amount of chemical fertilizer by 20 % in greenhouse tomato cultivation with organic fertilizer and biological agent.
In this study, lettuce was used as experimental material, the effects of different phosphorus application rates on yield, quality, soil available phosphorus content and agronomic efficiency of vegetable fields with high, middle and low phosphorus levels were studied by using the method of plot experiment. The results showed that the yield of lettuce of high phosphorus vegetable fields was the highest when the phosphorus application rate (P2O5) was 36.54 kg/hm2. When 54.91 kg/hm2 phosphorus (P2O5) was applied on medium phosphorus vegetable field, the yield of lettuce was the highest, the content of nitrate was lower, the content of vitamin C increased, and the content of soil available P was significantly increased. When 91.35 kg/hm2 phosphorus (P2O5) was applied on low phosphorus vegetable field, the yield of lettuce was the highest and the content of nitrate was decreased. The agronomic efficiency of phosphorus fertilizer decreased with the increase of soil phosphorus content and phosphorus application amount. Therefore, applying no phosphate fertilizer or little phosphate fertilizer on high phosphorus vegetable fields, combining medium phosphorus vegetable fields with medium phosphate fertilizer, and low phosphorus vegetable fields with high phosphate fertilizer were effective measures to improve the yield, quality and agronomic efficiency of nodular lettuce.
The primary objective of this study was to screen the most effective alginate acid fertilizers for enhancing strawberry production in the suburban areas of Beijing. To conduct this research, the ‘Hongyan’ variety of strawberries and commonly used alginic acid fertilizers were specifically chosen as experimental materials. Field trials were meticulously carried out to evaluate the impact of alginic acid fertilizers on the growth, yield and quality of strawberries. Compared to the CK group (water control treatment), the application of diverse alginate acid fertilizer treatments could promote the growth of strawberry plants. The T2 treatment (Haizaojing alginic acid fertilizer treatment) consistently exhibited superior effects on both plant height and petiole length within the two sheds. For instance, in shed 128, the plant height experienced a significant increase of 32.0%, and in shed 234, the petiole length had a substantial increase of 25.71% under the influence of the same treatment. Furthermore, the application of alginate acid fertilizers corresponded to a marked rise in the number of fruits per plant, consequently amplifying the overall yield. Notably, in shed 128, the implementation of the T2 treatment led to a noteworthy 18.47% increase in yield compared to the CK treatment. And in shed 234, the yield significantly increased by 23.36% with the application of the T3 treatment (Dalantong alginic acid fertilizer treatment). However, no significant differences were observed among the various alginate acid fertilizer treatments. The application of alginate acid fertilizers could improve fruit quality, such as increasing soluble solid content, sugar-acid ratio and vitamin C content, and reducing titrable acid and nitrate content. A comprehensive analysis of the findings emphasizes that alginic acid fertilizers play a pivotal role in promoting strawberry growth, elevating yield, and improving fruit quality. The T2 treatment has the best effect for multiple parameters.
Fruit expansion rule and dynamic change of soluble solid content of different batches of ‘Cuimi’ kumquat was studied. ‘Cuimi’ kumquat in Rong’an County of Guangxi was used as the experimental material. The transverse diameter and longitudinal diameter of the fruit were measured during the expansion period of different batches of fruits, and the soluble solids content of the fruit was measured at the maturity stage. The results showed that in the fruit enlargement stage of ‘Cuimi’ kumquat, the first and second batches of fruits were easy to form large fruits, and the third batch of fruits was smaller. In the early stage of fruit ripening, the soluble solids content of the second batch of fruit was the highest, and in the middle and late stages, the soluble solids content of the third batch of fruit was the highest. The results showed that the first and second batches of fruits expanded early, lasted for a long time to form large fruits, and the soluble solid content was also high, and the market price was high. Therefore, corresponding measures should be taken to preserve the first and second batches of fruits in production, so as to improve the yield and increase the benefit.
Horticulturae
