Dry Weight Of Seedlings Research Articles

Seed Priming Significantly Affects Germination and Post Germination Early Seedling Growth in Okra

Abstract Seed priming significantly affects germination and post germination emergence in seedling of plants. Okra is an important vegetable plays significant role in human nutrition. However, little information is available regarding effect of seed priming on germination and post germination early vegetative growth. Therefore, a pot experiment was conducted to find out the effect of seed priming on the emergence and seedling vigor in different okra varieties. Six local Bangladeshi okra varieties were primed in water for 24 hours and evaluated their germination and post germination emergence. The varieties were named as V1-V6 (V1 = Flash power, V2 = Durga, V3 = BARI dheros-2, V4 =Okra pornota, V5 =Dandy all green, V6 = Boishakhi). Post priming evaluation was done based on germination percentage, root-shoot length of seedlings, seedling height, and dry weight of seedlings, germination index and speed of germination at different days after sowing (5-15 DAS). Highest germination was observed in V3 (88.00%) and lowest was in V5 (25.33%). Root length was highest in V3 and V4 (8.77cm) and lowest was observed in V2 (5.15cm). Shoot length of the seedlings was highest in V3 (7.94cm) followed by V1 (7.33). Shoot length of the seedlings was lowest in V5 (5.12cm). Seedling height was highest in V3 (16.71cm) which was followed by V6 (16.26cm). The lowest seedling height was observed in V1 (12.50cm). Dry weight of the seedlings was highest in V3 (2.32g) which was followed in V1 (2.26g). The lowest dry weight was observed in V5 (1.99g). The variety V3 performed better in most of the evaluated parameters and suggested for commercial cultivation.

Effects of crop rotations on microbial community in rhizosphere soil of cucumber seedlings and its feedback

We studied the effects of 7-crop rotations and continuous - monocropping systems on soil microorganism and its feedback. The results showed that absolute abundance of soil bacteria (Pseudomonas and Bacillus) in tomato - celery - cucumber - cabbage and cucumber - tomato - cucumber - cabbage rotation were significantly higher than control (CK). Absolute abundance of soil fungi in tomato - celery - cucumber - cabbage, kidney bean - celery - cucumber - cabbage, cucumber - kidney bean - cucumber - cabbage and cucumber - tomato - cucumber - cabbage rotation were significantly higher than CK. Dry weight of cucumber seedlings was significantly positively correlated with bacterial (Pseudomonas and Bacillus) abundance, and negatively correlated with fungal count. The results of inoculation with Fusarium oxysporum f.sp. cucumerinum showed that plant dry weight of cucumber seedlings in tomato - celery - cucumber - cabbage, cucumber - kidney bean - cucumber - cabbage, cucumber - tomato - cucumber - cabbage rotation soil was significantly higher than other treatments, and their disease index was significantly lower than other treatments. There was no significant difference in dry weight of cucumber seedlings in rotation and CK in the soil sterilization test. The results of plant - soil feedback experiment showed that soil microbial changes caused by different rotation patterns had a positive feedback effect on growth of cucumber seedlings.

Investigating Usage Potential of Datura stramonium L. for Phytoremediation of 2,4-Dichlorophenol

In this work, the phytoremediation potential of 2,4-Dichlorophenol (2,4-DCP) from soil and wetlands by Datura stramonium L. (jimsonweed) was investigated. The medium of seedlings growing in a hydroponic system was adjusted to different concentrations (0.0, 75, 100, 125, 150, 175, 200, 225, 250 and 275 ppm) of 2,4-DCP. Four days later, the remediation rate of 2,4-DCP in the growth medium, and root-stem length, root-stem dry weight, lipid peroxidation (LPO), protein and photosynthetic pigment content of seedlings were evaluated. D. stramonium seedlings provided remediation of 2,4-DCP between 52-78% at all concentrations. In addition, the 2,4-DCP treatments inhibited the root-stem lengths and dry weights of seedlings compared to their controls, particularly at high doses such as 200-275 ppm, but not at low doses. The applications generally increased protein and LPO content of roots and leaves slightly, but did not affect chlorophyll. The results show that D. stramonium has a high usage potential for phytoremediation of 2,4-DCP.

In vitro Effect of Caesalpinia sappan and Crateva magna Extracts in Enhancing Seed Germination and Seedling Growth of KDML105 Rice Variety

Background: Rice (Oryza sativa L.) is a major cereal crops planted in Thailand for both local consumption and export. The objective of this study was to investigate the allelopathic effect of Caesalpinia sappan L. and Crateva magna (Lour.) DC. extracts in promoting a rice cultivar, Khao Dowk Mali 105 (KDML105) seed germination and seedling growth, at 7 and 14 days after sowing (DAS). Methods: The C. sappan and C. magna plants were cleaned with tap water and air dried in room temperature then cut into small pieces and ground into fine powder. Plant crude extracts was prepared using ethanol as solvent. Result: The results showed that rice seed treatment with C. sappan and C. magna extracts was significant (all p less than 0.05), increasing root length, shoot fresh and dry weight and root fresh and dry weight of rice seedlings at 14 DAS. Seed treatment with these two plant extracts led to a significantly greater vigor index of the KDML105 rice seedling cultivar, when compared with the control. Interestingly, the seed treatment with C. magna extract at a 100 ppm concentration was found to produce the highest enhancement in the overall rice seedling growth parameters, including the vigor index of seedlings. The results showed that a low concentration of C. magna extracts can be potentially used in promoting seedling growth of rice since they improved the overall growth parameters.

Experimental studies to identify the influence of low power monochromatic optical radiation on the seeding qualities of cucumber seeds variety “Feniks+”

A further increase in the volume of cultivated and harvested agricultural products today depends not on the expansion of sown areas, but on scientific achievements aimed at increasing yields. The experimental study presents the results of studying the effect of low-power monochromatic optical radiation on the seeds of cucumbers of the “Fenisk+” variety. The research is based on the principles of refusal to use chemical fertilizers, the use of natural organic substances, and the creation of conditions for the growth and development of plants, identical to the conditions of their natural growth. There are various physical effects, including those based on the use of electrical energy and its transformation into light energy. Monochromatic optical radiation can be attributed to such effects. Based on the analysis of the experimental results, regression equations were obtained for the dependence of the average dry weight of cucumber seedlings on the wavelength of irradiation and exposure, and the optimal range of wavelengths of optical radiation was found: from 565 to 615 nm. At these wavelengths, the best results were obtained in terms of seed germination, the length of shoots and roots, as well as the dry weight of the vegetative part and roots. Based on the results obtained, it is possible to formulate the technological requirements for the design and development of a specialized electrotechnical installation using monochromatic optical radiation in agricultural production with the aim of presowing stimulation of seeds of such a vegetable crop as cucumbers.

Allelopathic Potential of Haloxylon persicum against Wheat and Black Mustard with Special Reference to Its Phytochemical Composition and Antioxidant Activity

Haloxylon persicum is a well-known plant of sandy deserts, but yet, its allelopathic and phytochemical potential has not been explored. In the present study, we evaluated the effects of different concentrations (1, 2, 4, and 8%) of the aqueous extract of H. persicum shoots on seed germination and seedling growth of wheat crop and black mustard weed. The effects of the same extract on the biochemical parameters (chlorophyll a, chlorophyll b, carbohydrates content, and proline content) of wheat seedlings were also investigated. Low and moderate concentrations (1, 2, and 4%) of H. persicum aqueous extract nonsignificantly affected seed germination, shoot length, root length, fresh weight, and dry weight of wheat seedlings, whereas these parameters were negatively affected by the application of the highest extract concentration (8%). The results revealed a significant increase in proline content in wheat seedlings under all the applied concentrations of H. persicum extract. Low and moderate concentrations (1–4%) of H. persicum extract significantly enhanced chlorophyll a, chlorophyll b, and total chlorophyll content in wheat seedlings, whereas these parameters were significantly reduced when the highest extract concentration (8%) was applied. Only the lowest concentration (1%) of H. persicum extract reduced the carbohydrates content of wheat seedlings, while other concentrations showed nonsignificant effects. Concentrations of 4 and 8% of H. persicum extract reduced the seed germination percentage of black mustard. The root length, shoot length, and fresh weight of black mustard seedlings were significantly decreased by the application of 1 and 2% extract concentrations and completely inhibited in response to treatment with 4 and 8% concentrations. The dry weight of black mustard seedlings was not affected by 1 and 2% extract concentrations but completely inhibited at 4 and 8% concentrations. The methanol extract of H. persicum contains high contents of bioactive secondary metabolites, such as phenolics, flavonoids, flavonols, anthocyanins, tannins, saponins, as well as proved to has a very strong antioxidant activity of the 2,2-diphenyl-1-picrylhydrazyl radical scavenging activity (DPPH). Based on our results, we recommend the potential application of the aqueous extracts of H. persicum to control black mustard weed in wheat crops. Furthermore, H. persicum revealed an interesting phytochemical pattern with sound antioxidant activity that assigns this plant as a promising candidate to explore its detailed metabolomics profile along with potential bioactivities.

Exogenous Application of Brassinosteroid 24-Norcholane 22(S)-23-Dihydroxy Type Analogs to Enhance Water Deficit Stress Tolerance in Arabidopsis thaliana.

Brassinosteroids (BRs) are plant hormones that play an essential role in plant development and have the ability to protect plants against various environmental stresses, such as low and high temperature, drought, heat, salinity, heavy metal toxicity, and pesticides. Mitigation of stress effects are produced through independent mechanisms or by interaction with other important phytohormones. However, there are few studies in which this property has been reported for BRs analogs. Thus, in this work, the enhancement of drought stress tolerance of A. thaliana was assessed for a series of 2-deoxybrassinosteroid analogs. In addition, the growth-promoting activity in the Rice Lamina Inclination Test (RLIT) was also evaluated. The results show that analog 1 exhibits similar growth activity as brassinolide (BL; used as positive control) in the RLIT bioassay. Interestingly, both compounds increase their activities by a factor of 1.2–1.5 when they are incorporated to polymer micelles formed by Pluronic F-127. On the other hand, tolerance to water deficit stress of Arabidopsis thaliana seedlings was evaluated by determining survival rate and dry weight of seedlings after the recovery period. In both cases, the effect of analog 1 is higher than that exhibited by BL. Additionally, the expression of a subset of drought stress marker genes was evaluated in presence and absence of exogenous applied BRs. Results obtained by qRT-PCR analysis, indicate that transcriptional changes of AtDREBD2A and AtNCED3 genes were more significant in A. thaliana treated with analog 1 in homogeneous solution than in that treated with BL. These changes suggest the activation of alternative pathway in response to water stress deficit. Thus, exogenous application of BRs synthetic analogs could be a potential tool for improvement of crop production under stress conditions.

Effects of exogenous silicon on maize seed germination and seedling growth

As the global population continues to increase, global food production needs to double by 2050 to meet the demand. Given the current status of the not expansion of cultivated land area, agronomic seedlings are complete, well-formed and strong, which is the basis of high crop yields. The aim of this experiment was to study the effects of seed germination and seedling growth in response to silicon (from water-soluble Si fertilizer). The effects of Si on the maize germination, seedling growth, chlorophyll contents, osmoprotectant contents, antioxidant enzyme activities, non-enzymatic antioxidant contents and stomatal characteristics were studied by soaking Xianyu 335 in solutions of different concentrations of Si (0, 5, 10, 15, 20, and 25 g·L−1). In this study, Si treatments significantly increased the seed germination and per-plant dry weight of seedlings (P < 0.05), and the optimal concentration was 15 g·L−1. As a result of the Si treatment of the seeds, the chlorophyll content, osmotic material accumulation and antioxidant defence system activity increased, reducing membrane system damage, reactive oxygen species contents, and stomatal aperture. The results suggested that 15 g·L−1 Si significantly stimulated seed germination and promoted the growth of maize seedlings, laying a solid foundation for subsequent maize growth.

Silicon seed priming attenuates cadmium toxicity in lettuce seedlings.

This study aimed to evaluate the silicon (Si) capacity to attenuate the cadmium (Cd) effects on seed germination and seedling performance of lettuce. The seeds were subjected to three priming levels: without priming, hydropriming, and Si priming. Afterwards, the seeds were placed to germinate on paper moistened with the absence (0mM) and presence (1mM) of Cd. Seeds exposed to Cd showed the same percentage of germination verified in seeds unexposed to this metal (99%). Si priming increases 16% the germination speed of seeds not exposed to Cd and promoted greater expression of esterase during seed germination. However, Cd promoted the decrease of the intensity of esterase and acid phosphatase expression, regardless of the seed priming technique used. Although it does not influence the germination percentage of lettuce seeds, Cd markedly reduced the dry weight of seedlings. This harmful effect caused by the Cd was 33% minimized with Si priming. In addition to the lower weight, Cd induced a significant reduction in antioxidant activity in seedlings. However, Si seed priming caused a greater antioxidant activity-with emphasis on catalase-and, consequently, less lipid peroxidation. In conclusion, Si seed priming contributes to minimize the Cd effects in lettuce seedlings.

The effect of transplant age on vegetable growth characteristic in a cylindrical paper pot system

This study aimed to estimate the seedling performance of cylindrical paper pot (CPP) seedlings and to determine the optimal transplanting age of CPP seedlings based on seedling vigor. The studied vegetables were cucumber, tomato, paprika, and two varieties of cabbage, and the younger seedlings were obtained by shortening their raising period by 10 and 20 days with CPP. At the same transplanting age, the size of CPP seedlings was smaller pre-transplant but increased to a similar level to the plug seedlings soon after transplanting. The growth curves of leaf area and dry weight of younger CPP seedlings exhibited a steeper rise trend. The seedling vigor indicators, relative growth rate (RGR), net assimilation rate (NAR), were significantly increased in younger CPP seedlings of all vegetables, which were 10 or 20 days younger than plug seedlings. The compactness (CP) and seedling health index (SHI) of cucumber, and the leaf area ratio (LAR) and specific leaf area (SLA) of cabbage were significantly increased when shortened by 10 and 20 days, while the CP and SHI of paprika were significantly decreased when shortened by 20 days. Our results suggest that CPP may prevent the seedlings from overstretching and can provide a wild range of transplanting age choices to produce vigorous seedlings. Further, the seedling vigor indicators were successfully used to determine the transplanting age of CPP seedlings. The optimal transplanting age of CPP seedlings of tomato, paprika, and cabbage was 10 days younger than plug seedlings, whereas cucumber transplanting age could be decreased by either 10 or 20 days.

Titanium Dioxide Nanoparticles and Magnetic Field Stimulate Seed Germination and Seedling Growth of Cannabis sativa L.

In order to evaluate the effect of magnetic field intensities and concentrations of TiO2 nanoparticles on seed germination and seedling growth of Cannabis sativa L., this study was conducted. The experimental treatments included magnetopriming at intensities of 0, 30, 60, and 90 mili Tesla (mT), and the second factor included nanopriming at different concentrations of TiO2 nanoparticles, including 0, 10, 50, and 100 ppm. The results showed that sowing cannabis seeds by the combined use of magnetic fields and TiO2 nanoparticles had a significant effect on most of the studied traits. The effect of magnetic field levels showed that the highest dry weight of radicle, hypocotyl and seedling, the highest percentage of germination, germination rate, germination index and germination vigor index were related to the magnetic field at the intensity of 90 mT (5.3, 7, 6.8, 54.6, 110.9, 55.4, and 31.5% increase compared to the control, respectively). The results showed that the length and dry weight of radicle, hypocotyl and seedling were affected at the concentration of 10 ppm of TiO2 nanoparticles (2.84, 0.29, and 1.63, 0.62, 20.55 and 2.37%, respectively increase compared to the control). According to the study results, the decreasing trend of hypocotyl and seedling length was observed with increasing the concentration of nanoparticles. It is suggested to use the magnetic field as a non-invasive and non-destructive growth promoter of the plant and low concentrations of TiO2 nanoparticles as a useful tool to increase seed permeability through improving morphological and physiological properties for medicinal-industrial plant cannabis.

Impact of heat stress on germination and seedling growth of chili pepper (Capsicum annuum L.)

Temperature plays an important role in plant growth and development. The increased temperature suddenly may cause severe consequences. This study aimed to observe the impact of temperature, exposure of duration, and the interaction between temperature and exposure duration at the germination phase and seedling growth of chili pepper. The research design used Factorial Completely Randomized Design. The first factor was the temperature consisted of five-level of temperature i.e: 35°C, 37°C, 39°C, and 41°C. The second factor was the exposure duration consisted of four hours, eight hours, and twelve hours. The Parameters observed were the percentage of seed germination, shoot length, root length, number of roots, seedling height, number of leaves, fresh weight of seedling, dry weight of seedling, and chlorophyll content. The results of this study showed that there is an interaction between temperature and duration of exposure, the rise in the temperature and duration of exposure decrease shoot length 35.15%, root length (23.23%), number of roots (29.82)%, fresh weight of seedling (40%), number of leaves (30%), chlorophyll content. As a result, the growth of Chili seedling showed a drastic reduction in shoot development, root development, and physiological parameters tested, the germination stage is very susceptible to raise the temperatures.

Effect of Plant Growth Promoting Rhizobacteria (PGPR) on Salt Stress Tolerance of Barnyard Millet (Echinochloa frumentacea)

Salinity stress is a crucial environmental stress adversely affecting crop production by plummeting crop growth. The impacts of rhizobacteria to alleviate salinity stress on germination and growth of barnyard millet were assessed using different concentration of NaCl. It is a well acknowledged strategy to improve plant salt tolerance through inoculation with beneficial microorganisms. The results indicated that the PGPR significantly improved germination percent, root and shoot length and fresh and dry weight of seedling and leaf chlorophyll under salt stress in comparison to non-stressed and plants without inoculants. The results of present study showed that PGPR could be helpful to alleviate the salinity stress at the time of seed germination and growth. It can be concluded that PGPRs are the cost effective and economical tool for salinity tolerance and growth promotion in crop plants.

Influence of stages of fruit maturity on germination, growth and vigour of papaya (CV. Solo) seedlings

Investigations carried out at Department of Horticulture, College of Agriculture, Dharwad during the year 2015-16, to assess the influence of different stages of fruit maturity on germination, growth and vigour of papaya (cv. Solo) seedling, revealed that the harvesting of fruit at 3/4 ripe stage significantly increased the germination percentage (48.00%), dry weight of seedling (8.50 mg) and vigour index (1179.55) as compared to fruit harvested at other stages of maturity. Fruit at 3/4 ripe stage also recorded highest 100 seed weight.

Physiological potential of green bean seeds treated with Bacillus subtilis

Abstract: The association between beneficial microorganisms and green beans can accelerate establishment in the field. The objective of this study was to investigate the influence of seed treatments in different doses of Bacillus subtilis on the physiological potential of green beans. Seeds from the cultivar Macarrão Baixo were used. The study used a completely randomized design in a double factorial scheme with factor A in the treatments: Pelliculation (PC), Pelliculation with Drying (PCD), Pre-Imbibition (PI), Biopriming (BP); factor B, doses of B. subtilis: 0; 7; 14 and 28 mL of a commercial product.kg of seed-1, and a control. The following treatments were applied: moisture content analysis, first count and final germination, electrical conductivity, length, fresh and dry seedling weight, speed index, and final emergence. Analysis of variance was applied to the data and when significant, it was compared using Tukey’s test and polynomial regression; for the absolute control, orthogonal contrast was applied, with p &lt; 0.05 for all analyses. The treatments did not impair seed viability. Vigor benefited with the use of PI and doses between 16 and 20 mL of p.c.kg of seed-1. PI alone had the best performance. Biopriming, associated with B. subtilis, favors the vigor of green beans.

Seed Quality of Sorghum [Sorghum Bicolor (L.) Moesch] as Affected By Seed Priming and Storage

Sorghum is being produced primarily as a food grain throughout the world. It is one of the major traditional food crops in Ethiopia. However, the productivity of the crop is very low and poor seed quality is one of the major determinants. An experiment study was conducted in laboratory and glasshouse to evaluate the effect of seed priming on seed quality parameters of three sorghum varieties:(Muyra-I, Muyra-II and Fendisha) with different storage of one year and two years using different priming agents with different soaking time for each priming agent (1.0mM KNO3, 1mM NaCl and distilled water for 72, 48 and 12 hours respectively) in 2012 at Haramaya University Seed laboratory. Completely randomized design in 2 x 3 x 4 factorial arrangement with three replications was used to carry out the germination and vigor tests. The priming concentrations and durations were based on previous work, which was effective in hydro and osmo-conditioning of sorghum seed. In the experiment, seed priming increased germination percentage (GP), Mean Germination Time (MGT) and improved seedling shoot (SSL) and root length (SRL), seedling dry weight (SDW) and seedling vigor indices in all varieties of both storage durations compared to their respective control. Priming with NaCl and KNO3 showed positive response followed by hydropriming for all varieties of different storage duration. When treated with sodium chloride, almost all the varieties of each storage year demonstrated an increase in germination and the degree of increment was higher for Muyra-I(__) and Fendisha (___), the lowest being for Muyra-II which was significantly lower for both storage year. In case of mean germination time Fendisha exhibited better with hydropriming for older seeds (___) and with KNO3 for newer seeds(___) while Muyra-II and Muyra-I showed better with KNO3 (____) for older seeds and with hydropriming for newer seeds. Responses of varieties for the remaining parameters were intermediate. Therefore, sorghum seed priming with osmo-media and water can compensate storage deterioration of sorghum seeds in addition to significantly improving the seed germination and vigor quality parameters

Optimization of EMS mutagen dose for short day onion

The present experiment was conducted to investigate the effect of chemical mutagen on biological parameters such as seed germination, shoot and root length and to fix the lethal dose (LD50) of EMS in short day Indian onion cultivar Bhima Dark Red. Presoaked seeds of onion were treated with different doses (0, 0.2, 0.4, 0.6, 0.8, 1.0, 1.2 % v/v) of Ethyl Methane Sulfonate. The optimal mutagenic doses were calculated using Probit Analysis based on germination percentage which were considered useful in developing onion mutagenized population to create genetic variability for various qualitative and quantitative traits. Seed germination was recorded after 7 and 12 days of sowing, while seedling parameters such as seedling height, dry and fresh weight of seedlings were taken after 12 days. Data revealed that the mutagenic agent significantly reduced seed germination and seedling growth parameters in terms of shoot and root length as compared to control. Significant reduction in the seed germination percent with the enhancement of concentration of EMS dose was exhibited.

Trichoderma asperellum promotes cadmium accumulation within maize seedlings

Cadmium (Cd) is one of the most toxic heavy metal pollutants known to accumulate in the soil environment and pose a threat to public health. The tolerance of endophytic fungi isolated from Kosteletzkya virginica to cadmium was determined by the Oxford cup method. Trichoderma asperellum displayed the highest tolerance to cadmium on potato dextrose agar (PDA) medium and was selected subsequently for inoculating maize seedlings. Green fluorescein protein (GFP) labeled T. asperellum colonised in the roots of maize seedlings. Under Cd stress, the plant height, dry weight, fresh weight, root length, chlorophyll content and antioxidant enzyme activity of maize seedlings inoculated with T. asperellum were significantly higher than those of the control. T. asperellum also contributed to the up-regulated expression of some key genes in roots and leaves of maize seedlings, involving nitrogen absorption and metabolism to promote maize growth and Cd detoxification, accumulation, distribution, etc. for Cd transport to increase resistance to Cd.

Role of soil bacterial consortia on glyphosate degradation and growth of maize seedlings

Pre-growing weed control by glyphosate herbicides is effective for increasing yield, but glyphosate residues in the soil might reduce soil quality and can accumulate in agricultural products. Naturally, microbes are able to breakdown glyphosate into nontoxic substances orthophosphate and glycine. Glyphosate degradation in soil by single soil microbes are reported elsewhere, but the information about glyphosate removal by soil bacterial consortia was limited. The objective of this research was to determine the effect of carbon (C), nitrogen (N), and phosphorus (P) composition in liquid media to increase glyphosate degradation and its degradation product by soil bacterial consortia and 2) verify the effect of bacterial consortia on maize seedlings growth, their N and P uptake, as well as total and soluble P in soil. Glyphosate degradation test was set up by incubating bacterial consortia in a different composition of C-N-P liquid basal media. Greenhouse experiment has been performed in a randomized block design to treat maize grown in Inceptisols with bacterial and glyphosate application. The results showed that C-N-P composition of liquid media affected the concentration of glyphosate, as well as orthophosphate and glycine as by-products. In-planta experiment verified that inoculation of glyphosate-degrading bacterial to maize seedling grown in glyphosate-contaminated soil enabled to enhance shoot dry weight of maize seedling and N and P uptake at 4 weeks after inoculation.

A Biocontrol Strain of Pseudomonas aeruginosa CQ-40 Promote Growth and Control Botrytis cinerea in Tomato.

Botrytis cinerea infection can be very devastating for tomato production, as it can result in a large-scale reduction in tomato fruit production and fruit quality after harvest. Thus, it negatively affects tomato yield and quality. In this study, a biocontrol bacteria CQ-4 was isolated and screened from the rhizosphere soil of tomato plants. Morphological, physiological, and biochemical characteristics and 16S rDNA sequence analysis revealed that it belongs to the species Pseudomonas aeruginosa, which has a strong antagonistic effect against Botrytis cinerea. In addition, the bacterium’s antibacterial spectrum is relatively extensive, and antagonistic tests have shown that it also has varying degrees of inhibition on other 12 plant diseases. The growth promotion test showed that the strain has a clear promotion effect on tomato seed germination and seedling growth. The growth-promoting effect on plant height, stem thickness, dry and fresh weight and main root length of tomato seedlings was significantly improved after the seeds were soaked in a bacterial solution of 2.5 × 108 cfu mL−1 concentration. This did not only maintain the nutritional quality of tomato fruits, but also prevents them from rotting. In vitro and pot experiments showed that the strain CQ-4 can effectively control tomato gray mold, and the control effects on tomato leaves and fruits reached 74.4% and 66.0%, respectively. Strain CQ-4 induce plants to up-regulate the activities of four disease-resistant defense enzymes. The peak enzymatic activities of Phenylalanine Ammonia Lyase (PAL), polyphenol oxidase (PPO), peroxidase (POD), and Superoxide Dismutase (SOD) were increased by 35.6%, 37.6%, 46.1%, and 38.4%, respectively, as compared with the control group. This study found that the strain can solubilize phosphorus, fix nitrogen, and produce cellulase, protease, ferrophilin, and other antibacterial metabolites, but it does not produce chitinase, glucanase, and HCN (hydrocyanic acid). This research screened out an excellent Pseudomonas aeruginosa strain that can stably and effectively control tomato gray mold, and it provided theoretical basis for further development and the application of biological agents.