The study was carried out in field conditions and use conventional compound fertilizer as the control group to explore the effect of compound fertilizers containing 2%, 4%, 6%, or 8% humic acid on the yield and quality of chilli. The effect of humic acid-compound fertilizer treatment under continuous cropping conditions was investigated, 6% humic acid-compound fertilizer was conducted for four consecutive years and using conventional compound fertilizer as the control group. The results show that humic acid fertilization significantly improved the yield and quality of chilli, and the overall improvement was directly proportional to the dosage of humic acid. An evaluation based on benefit, yield, and various quality indicators concludes that compound fertilizer with 6% humic acid was the optimal ratio, which increased the yield by 14.07% in the first year compared to that in the control group. The application of humic acid-compound fertilizer effectively reduced the impact of continuous cropping on the yield and quality of chilli, and the combined decline in the yield and quality was significantly less than that in the control group. In the fourth year, the yield of 6% humic acid-compound fertilizer treatment was 33.6% higher than that of conventional fertilizer.

For exploring the green methods of soil disinfection, the disinfection effects of ozone water at different mass concentrations on three soil-borne pathogenic fungi, Fusarium oxysporum, Rhizoctonia solani, and Botrytis cinerea, were studied. The results showed that ozone water in the mass concentration range of 1.0~5.0 mg/L has certain sterilizing effect on the spores of the three pathogenic fungi. The mass concentration of ozone water is the main factor affecting the sterilization rate, whereas the treatment time has no significant effect on it. Increasing the mass concentration of ozone water and the frequency of irrigation can significantly enhance the sterilization rate of the three pathogenic fungi in the soil. Irrigation of the soil with ozone water can significantly reduce disease incidence in plants. However, it leads to growth inhibition, and the introduction of Trichoderma can eliminate this inhibition.

To explore rapid utilization methodsfor pruning apple branches, cucumber (Jinyan No. 4) was used as a test material to study the effects of Trichoderma harzianum T11-W and apple branch sawdust on its seedling growth. T. harzianum T11-W was added to the sawdust in advance in one group (this was considered treated sawdust), whereas the other group involved the simultaneous addition of T. harzianum T11-W to sawdust. These two groups were compared with untreated apple branches (raw sawdust) and T. harzianum T11-W alone. Results showed that T. harzianum T11-W exhibited the most significant growth-promoting effect on cucumber seedlings, and when the mass fraction of sawdust was 0.7%, the root length inhibition of sawdust was weakened and the dry weight of its root was further increased by adding T. harzianum T11-W. Although the comprehensive evaluation of Trichoderma with sawdust treatment (treated sawdust or raw sawdust) was not as good as that of T. harzianum T11-W treatment alone, they have the highest root-cap ratio. When the raw sawdust dosage was 0.35%, the promotion of cucumber seedling growth was weaker than that of the control group that did not undergo any treatment. When the dose was 0.7%, the growth-promoting effect was higher than that of the above-mentioned control group, indicating that increasing the amount of raw sawdust facilitated cucumber seedling growth. When the sawdust dosage was 0.35%, the growth-promoting effect of treated sawdust on cucumber seedlings was better than that of raw sawdust. 

To evaluate the control potential of Trichoderma wettable powder against tomato Fusarium wilt, we tested the control efficacy of Trichoderma wettable powder (2×10⁸  cfu/g) on tomato Fusarium wilt in field experiments. The result demonstrated that the use of Trichoderma wettable powder (15 000 g/hm²) could remarkably control Fusarium wilt diseases for tomatoes and the efficacy was maintained at >70% after 90 days of treatment. Therefore, the control efficacy of Trichoderma wettable powder on tomato Fusarium wilt was equivalent to that of the control agent. This was suitable to control tomato Fusarium wilt and could significantly promote the growth of tomatoes.

The effects of compound fertilizer replaced by compound microbial fertilizers in different proportions on rhizosphere soil environment and yield of peanut were studied by field experiment. Results showed that, compared with conventional fertilization (100% compound fertilizer), compound fertilizer replaced from 30% to 70% by compound microbial fertilizers, significantly increased the total amount of bacteria, fungi and actinomycetes in rhizosphere soil of peanut at seedling and maturity stage, and the number of bacteria and actinomycetes in rhizosphere increased gradually with the growth of peanut, while the number of fungi showed the opposite tendency. Meanwhile the activities of soil catalase, dehydrogenase, neutral phosphatase and sucrase at seedling stage were significantly increased, while the activities of soil urease were decreased at 50% and 70% substitution levels. However, the activities of soil urease and sucrase were decreased, while dehydrogenase was increased at maturity stage by different substitution ratios. The content of soil alkaline hydrolyzable nitrogen decreased, but the total nitrogen content increased at seedling and pod stage, meanwhile，soil organic matter and soil available potassium increased at each growth stage, and soil available phosphorus concentration at pod and mature stage. When the substitution amount was 50%, the yield was increased by 5.23%, consequently realizing the effect of increasing yield by enriched soil.

The species richness, diversity and composition of fungal community in wheat rhizosphere soil at different developmental stages with Trichoderma LTR-2 seed dressing agent were analyzed using Illumina MiSeq high-throughput sequencing platform. The results demonstrated that Trichoderma treatment of wheat seed increased the species richness of fungal community in the rhizosphere, and the community dominance increased significantly, while no obvious changes in the community uniformity were observed. In addition, the community composition was found similar with and without Trichoderma treatment. However, the proportion of various fungal groups in the rhizosphere changed significantly with Trichoderma treatment, among which Alternaria spp., Gibberella spp., and Fusarium spp. were decreased compared to non-seed dressing treatment. All the results provide a theoretical basis for better understanding the biocontrol mechanism of Trichoderma sp. LTR-2 against wheat soil-borne diseases.

In order to improve the biomass of Arthrobacter ureafaciens DnL1-1, the fermentation medium of the strain DnL1-1 was optimized by single factor screening and orthogonal experiment. The results showed that the best formula should be: glucose 15.0 g/L,peptone 7.5 g/L,yeast extract 0.50 g/L,K₂HPO₄ 2.0 g/L,KH₂PO₄ 1.0 g/L,CaCl₂ 0.15 g/L,MgSO₄ 0.15 g/L.Thus the strain can produce about 2.89×10¹⁰ cells in 1 mL of the culture medium under the condition of 1% inoculum, with shaking of 180 r /min at 28 ℃ for 36 hours.

The effects of maize straw incorporation and decomposition inoculants on soil physical and chemical properties, microbial biomass, enzyme activity and wheat yield were studied by field experiment. Results showed that, compared with the treatment that without straw incorporation (CK), straw incorporation (T1) and straw incorporation with decomposition inoculants (T2) significantly decreased soil bulk density, increased the number of soil bacteria and actinomycetes, and the activities of some rhizosphere soil enzyme, such as soil urease, neutral phosphatase and invertase, and further increased the content of soil available nutrients and organic matter, and the final wheat yields significantly increased by 10.33% and 13.46%, respectively. In addition, compared with CK, T2 decreased the number of fungi, and increased soil catalase and dehydrogenase activity in rhizosphere soil, but the differences in T1 treatment were not obvious. In summary, straw return could regulate soil enzyme activity and nutrient content by improving microbial community biomass and diversity, thus optimizing rhizosphere environment and promoting wheat growth. Among them, the treatment effect of straw incorporation with decomposition inoculants was better than only straw incorporation treatment, which could be popularized and applied in maize planting area of the north of China.

In this study, the effect of Trichoderma water dispersible granules (1×108 cfu/g) on the control of wheat sheath blight was tested by field experiment. The results showed that the control effect of Trichoderma seed dressing and root irrigation reached 71.59% and the increasing yield rate of wheat was 16.8%. Both were obviously higher than that of the control pesticide, 20% Jinggangmycin soluble powder. As a microbial pesticide, Trichoderma water dispersible granules have the advantages of environmental safety, high selectivity, and not easy to induce resistance by pathogen.

In order to improve the field control effect of Bacillus cereus BCJB01 pulvis on rootknot nematode in vegetables, a field study on the control of tomato rootknot nematode disease by Bacillus cereus BCJB01 was carried out by the way of adding nutrient matrix and organic fertilizer. The results showed that adding organic fertilizer and nutrient matrix at the same time when cultivating land was the best method to control tomato rootknot nematode. The control effect was up to 77.45%, which was superior to that of 10% thiazone granule.

In order to improve the control effect of Burkholderia vietnamiensis and its composite microbial flora on rootknot nematode in vegetables, taking the cucumber rootknot nematode as the research object, we adopted the way of adding nutrient matrix, biobacteria fertilizer and microbial antimicrobial agents when cultivating land, and fertilizing microbial antimicrobial agents when transplanting, carried out research for application technology on Burkholderia vietnamiensis B418 and its combinations with Bacillus cereus BCJB01, Trichoderma spp.LTR-2 and T11-W. The results showed that the addition of nutrient substrate when cultivating land could significantly improve the control effect of B418 to rootknot nematode. In the treatment of composite microbial flora, the treatment of cucumber rootknot nematode by adding bio-bacteria fertilizer and nutrient matrix at the same time when cultivating land was better than that of single nutrition matrix or bio-fertilizer. B418 single agent add nutrient matrix treatment was superior to its composite microbial flora add nutrition matrix treatment, whose field control effectiveness was 90.05%.

Through selective medium, the function of fixing nitrogen and dissolving phosphorus of 26 Agrobacterium strains were studied by both qualitative and quantitative analysis methods. Meanwhile, growthpromoting effect of Australian biocontrol strain K1026 on cucumber and wheat was measured by pot experiment. The results showed that all the strains regardless of pathogenicity or nonpathogenicity could grow normally on nitrogenfree medium. 19 of the 26 strains had the ability to dissolve phosphorus, the Phosphate released by K1026 in Pikovskaya broth medium was up to 109.11 μg/mL , having the strongest activities among all stains. The pot experiments showed that K1026 had obvious growthpromoting effect on the cucumber seedlings, and the root length and the dry weight of the root biomass was increased by 25.49%, 62.96%, respectively, compared with the control. However, K1026 had no obvious effect on the growthpromotion of wheat.

To increase the spore production of Bacillus atrophaeus BsR05, a response surface method was applied to optimize the technological conditions of BsR05 fermentation medium. Corn flour, (NH4)2SO4 and MgSO4·7H2O were selected as the major factors affecting sporulation by means of PlackettBurman design. The method of steepest ascent path was adopted to determine the response center and the optimal concentration range of these 3 factors. Finally, the regression relationship between the main medium composition and the spore yield was established by BoxBehnken design. The optimal formula for the fermentation medium was determined as follow：glucose 5 g/L，corn flour 15.9 g/L, soybean meal 40 g/L, K2HPO4 3.0 g/L, KH2PO4 1.0 g/L, (NH4)2SO4 2.1 g/L, MgSO4·7H2O 0.40 g/L and MnSO4 0.020 g/L. After repeated experiments, it was verified that the average spore content was basically consistent with the predicted spore content, and the concentration of the spore was increased from 4.73×109 CFU/mL to 6.02×109 CFU/mL after the optimization.

To improve fermentation level of Bacillus cereus BCJB01, a highly efficient biocontrol strain against downy mildew, we optimized its fermentative medium through orthogonal test, comprehensive optimization and sugar feeding tests. Mass fraction of the optimized medium formula are 2.00% corn meal,1.00% soybean powder, 0.0030% manganese chloride tetrahydrate, 0.30% twelve aqueous disodium hydrogen phosphate, 0.15% sodium dihydrogen phosphate dihydrate, 0.035% magnesium sulfate heptahydrate, 0.10% calcium chloride, 0.30% yeast extract, 0.2%sugar added at 6~12 h after inoculation. It can produce more than 100×108 cfu/mL cells and its spore rate is 90%, when the cultivation conditions are 3%(V/V) inoculum size, 180 r / min rotation velocity, 30 ℃ shaky cultivation till 66 hours.

Synchytrium  decipiens, an obligate parasite in Amphicarpa eaedgeworthii Benth., infects legume and rhizoid of Amphicarpaea edgeworthii Benth.Irregular nodular intumescentia will then shape. Large amount of trophosomes of pathogenic bacteria in tumor body will hinder the transport of water and inorganic nutrients, and eventually cause exsciccation of Amphicarpaea edgeworthii Benth.We originally report Synchytrium decipiens in the legume and rhizoid of Amphicarpaea edgeworthii Benth.We also make preliminary observation and investigation. This provides a reference for resource development of Amphicarpaea edgeworthii Benth,identification of plant disease morphology and prevention and cure of insect pest in artificial cultivation.

We detected, enumerated and isolated atrazinedegrading bacteria from herbicide contaminated soil by improved agar SM. We found that atrazine degraders constituted a major component of microbial communities in industrially contaminated soils, but a minor component in agricultural soils. We also analyzed targeting genes trzN and atzABC with multiplex PCR, which indicated that trzN and atzABC combination included degraders were prevalent in Shandong agricultural and industrial soils. Due to elimination of enrichment bias, direct isolation was more favorable for the diversity analysis of atrazine degrading bacteria.

We identified and classified 116 atrazinedegrading strains directly isolated from industrial and agricultural soil samples polluted by herbicides. We discovered 12 phylotypes among them through phylogenetic analysis of ERICPCR genotyping and 16S rRNA gene. Among the 12 phylotypes, we identified 8 phylotypes belonging to Arthrobacter bacteria in industrial soils, which are similar to phylogenetic groups of A.aurescens. We also detected identical genotypes within phylogenetic groups of Pseudomonas alcaliphila and Gulosibacter molinativorax in heavily contaminated no plant industrial soil. Only 3 phylotypes were distinguished in agricultural corn root soil. Bacteria genetically similar to Arthrobacter ureafaciens were ubiquitous and predominant atrazine degraders in agricultural soils. The other 2 phylotypes were distant Nocardioides spp.Genetic typing results indicate specific environment of genetic structures and diversity of atrazinedegrading microbial colonies. Contamination rate in industrial soils is the main factor affecting degrading diversity and genetic structures.

Trichoderma agent has promotion effect to biofertilizer, which is an important index to evaluate the efficacy of biofertilizer. However, its growth promoting effect is rarely evaluated in field conditions. We applied three Trichoderma agents with different functionalities to the processing for winter wheat, and plate dilution method to calculation of its colony numbers in earth. We also calculated seedling numbers and seedling period biomass of winter wheat, epiphytotic morbidity and yield of winter wheat. All three Trichoderma agents could successfully colonize and remain active in the whole growth season. T11W content was relatively higher in preharvest soil. Tr01 content was the highest at harvest time. Results show that LTR2 improves seedling emergence of 120.97%, seedling biomass of 54.59%, reduces wheat sharp eyespot disease index of 16.60%, wheat stripe rust disease index of 35.14%, and increases yield of 4.83%. T11W can increase seedling emergence of 146.77%, seedling biomass of 59.54%, but has negative effects toprevention and treatment of controlled diseases and increases yield of 37.79%. Tr01 can increase seedling emergence of 150.00%, has no significant effect to seedling biomass.It can reduce wheat sharp eyespotof 36.49%, but has no positive effect to the reduction of wheat stripe rust.The three Trichoderma agents have different promotion effects to the growth of winter wheat, so they have promotional application value. Our research provides data for research and development of Trichoderma agent.

We isolated three Trichoderma strains, Z19, CX584 and CY3585, from soils of Tibet, Shandong and Yunnan by selective medium THSM. These strains were identified by ITS rDNA and TEF1α sequences and morphological characteristics. Results show that the three Trichoderma strains were Trichoderma harzianum species complex,T. afroharzianum, T. atrobrunneum and T. simmonsii. These three species are all new record to China.

We addressed the impact of Trichoderma harzianum strain LTR-2 on seed germination, seedling growth and physiological and biochemical response of cucumber, radish and tomato under salinity stress. Results show that germination rate of vegetable seeds treated with LTR-2 is significantly higher than that of seeds untreated with LTR-2 under NaCl stress. Shoot length, fresh weight, chlorophyll content, net photosynthetic rate (Pn value) and antioxidant enzyme activity of vegetable seedlings treated with LTR-2 are significantly higher than those of seedlings without LTR-2 treatment. However, relative conductivity and MDA content are less than those without LTR-2 treatment. This indicates that T. harzianum strain LTR-2 can stimulate germination of vegetable seeds, growth and photosynthesis of seedlings, improve antioxidant capacity of seedlings, reduce membrane damage, and enhance salt tolerance of seedlings.

Trichoderma strain Y15 was isolated from the vegetable soil under Shandong greenhouse, and identified by analysis of internal transcribed spacer regions of the rRNA gene cluster (ITS), partial sequences of transcription extensions factor 1alpha (tef1α) and morphological characteristics. Results show that Y15 is T. paratroviride. The strain is colony dense, panniform, greyishgreen on PDA. Conidiophore main axes is long with short secondary branches, not extensively rebranching. Its branches are coupled or verticillate. Phialides usually has 2~4 verticils, lageniform or subulate, straight or flexuous. Conidia is subglobose to obovoid, greenish and smooth. The tef1α sequence of strain Y15 has 99% homology with strains S489 and S385 of T. paratroviride type, and has the closest genetic relationship with them in phylogenetic tree. It is originally reported in China as a new Chinese record of genus Trichoderma.

We collected 837 soil and water samples from the coastal beaches and wetlands ofthirteen provincesand autonomous regions, 827 Trichoderma stains among which were isolated. Experimental results show that Trichoderma is more easily isolated from soil samples than from water samples. Moreover, lower salt content in soil samples is more easy for Trichoderma isolation.Altitude is another vital factor influencing Trichoderma distribution.Isolation rate of Trichodermais the highest when its altitude ranges from 100 m to 1 200 m. This may attribute to the rich vegetation at such altitudes.

6 strains exhibiting antagonistic activities against grape downy mildew blight were obtained by the method of plate observation．By the detection of metabolites, the strain BMJBN02 was provided with the optimum efficiency of cellulase,chitinase and β1,3glucanase, and its hydrolysis circle on the plant was the largest. The results showed the strain BMJBN02 was identified as Bacillus.megaterium,through analyzing its morphological,physiological and biochemical characteristics,16S rDNA sequence and phylogenetics．Using the leaf disc for screening, it was significant that area of the mold layer significantly reduced inhibitory effect in leaves treated by strain BMJBN02, with the disease incidence reduced from 100% to 42.3% and disease stage reduced from 65.3 to 18.6.

We employed classical experiment methods and molecular identification technology to identify T11W and its parasitism to Meloidogyne incognita eggs to investigate the parasitism of strain T11W to M. incognita eggs. Results show that strain T11W is Trichoderma harzianum and it has parasitism to M. incognita nematode eggs. It has correction parasitism rate of 73.46% and relative hatch inhibition rate of 94.19%. Our research improves the theory of the prevention of Trichoderma harzianum to M. incognita.It has the prospect of acting as a new and highly efficient microbial nematicide.

We prevented vegetable gray mold diseases for tomato, eggplant, color pepper, chili, lentil, and cucumber with Trichoderma LTR2 wettable powder (1500 g/hm2) as spray. This provided 77.96%, 64.45%, 71.43%, 70.24%,72.71%, and 75.41% protection and control effect. Pyrimethamil 40% SC of 480 g/hm2 dilution could give control effect of 71%~81%. Spray time of Trichoderma LTR2 wettable powder should be in the early period of the disease. The wettable powder can effectively prevent vegetable gray mold disease with spray frequency of 7 days, continuous employment of 2~3 times, and the dosage of 1 500 g/hm2.

     Trichoderma spp. is a kind of multifunctional probiotics fungus that can stimulate crop growth and increase its capability against abiotic and biotic stresses. However, advanced and systematic global research is very limited in the areas of its plant salt tolerance increase and function mechanism. This paper addresses the impacts of Trichoderma harzianum LTR-2 on NaCl tolerant physiological characteristics of peppermint (Mentha piperita L.). Results show that LTR-2 can effectively alleviate growth inhibition and photosynthetic damage of peppermint under 200 mmol/L NaCl stress. The paper also investigates the physiological and biochemical basis of NaCl stress tolerance of LTR-2 inoculated peppermint. Results indicate that LTR-2 can increase antioxidant activity of peppermint and reduce ROS accumulation. It can also increase the activities of plasma membrane (PM) and tonoplast H⁺ATPase and Na+/H+ antiporter and then regulate salt absorption and distribution. These results provide experimental basis for the development and application of peppermint and LTR-2 in saline soil.

        More than 10 000 bacterial strains were separated from rhizosphere soil of vegetables from Tianjin, Hebei, Shandong, Shanxi, Fujian, Henan and Jiangsu, from which 802 strains exhibiting obvious antagonistic effect on Phytophthora capsici were selected. We further screened 62 strains having better antagonistic effect on Rhizoctonia solani, Botrytis cinerea and Pythium aphanidermatum from these 802 strains. Greenhouse pot experiments against P. capsici show that control effects of 6 strains are higher than 70%, Control effects of strain TB1340, 82%, are highest. Determination results of its biology characteristics demonstrate that it has stronger activity producing chitinase, cellulase and β-1,3-glucanase. It is preliminarily identified as Bacillus sp. by 16S rRNA sequence analysis combined with morphology observation.

      We employed floating leaf disc test to determine the control effects of antagonistic Paenibacillus polymyxa PB-2 against grape downy mildew. Results show that when PB-2 is 10⁸ cfu/mL,the fermentation broth and  aseptic fermentation filtrate both have better inhibitory effects on grape downy mildew. Their inhibitory rates are 77.21% and 60.24%. We also prepared wettable powder (WP) of PB-2. Field tests indicate that the relative control effects of 50 and 100 times dilution PB-2 WP against grape downy mildew are 46.91% and 36.99% after 1 week and 46.44% and 42.10% after 2 weeks. This demonstrates that PB-2 WP has better field application prospect for controlling grape downy mildew.