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Aim: To develop a liquid formulation based on Bacillus subtilis-34 using rice to evaluate the shelf life under refrigerated and room conditions and to evaluate the effect of different addition times of the formulation on the control of Meloidogyne javanica and growth of lettuce plants. Statistical Design: The design was completely randomized, with five treatments and eight replicates. The results were submitted to analysis of variance and the means were compared by the Scott Knott test with 5% error probability. Location and Duration of the Experiment: The experiment was set up during the period from 02/13/2018 to 03/20/2018 in a greenhouse located at the State University of Montes Claros, municipality of Janaúba, MG, Brazil. Methodology: Treatments consisted of drench in the substrate of tubes at 8 and 15 days; drench in the substrate of tubes at 8 and 15 days and in pot at 25 and 35 days; irrigation in pot only at 25 and 35 days after transplanting and 2 controls (Onix® and absolute control). All pots with plants were inoculated with 5000 nematode eggs. At 45 days of transplanting, the following nematological variables were evaluated: number of galls, number of egg mass, number of eggs per gram and reproduction factor, and agronomic variables fresh and dry biomass. Results: Additions in the tube and pot and in the pot only were efficient for the reduction in the reproduction of M. javanica and for the improvement of lettuce plant growth. Conclusion: B. subtilis-34 remains viable until 9 months in formulation stored under the refrigerator and up to 7 months under room conditions.

Objective: To evaluate under controlled conditions the effect of alternative liquid Bacillus subtilis isolate 34 formulation on Meloidogyne javanica and tomato growth promotion. Statistical Design: The design was completely randomized block with five treatments and eight replicates. The results were submitted to the analysis of variance and the averages compared by the Tukey test with 5% error probability. The statistical package used in the analysis of the data was the program "Sisvar" Location and Duration of the Experiment: The experiment was set up during the period from February 13, 2018 to April 20, 2018 in greenhouse located at the State University of Montes Claros, municipality of Janaúba, MG, Brazil. Methods: Treatments consisted of different times of application of bacteria in tomato seedlings: application of bacteria in the tube at eight and fifteen days after emergence; application of bacteria in the tube at eight and fifteen days after emergence and in pots at 25 and 35 days after transplanting; application of bacteria at 25 and 35 days after transplantation in the pot; Onix® commercial product (Bacillus methylotrophicus-UFPEDA20) and control. After 60 days of transplanting, the number of egg masses, number of galls, number of eggs, number of second-stage juveniles (J2) and reproduction factor, height, fresh and dry shoot mass and fresh root mass of tomato plants were evaluated. Results: There was a reduction in the number of J2, eggs pre root, and eggs per gram of root when the bacteria formulation was applied in the tube + pot and in pot only. The application of the bacteria in the tube + pot and in only pot only presents the highest increase of fresh and dry shoot mass and fresh root mass. Conclusion: The application of the liquid B. subtilis isolated 34 formulation to the soil in the pot and tube + pot reduced the reproduction of M. javanica and promoted greater tomato development.

Made available in DSpace on 2022-04-29T08:36:54Z (GMT). No. of bitstreams: 0 Previous issue date: 2021-01-01 Root-knot nematodes (Meloidogyne spp.) are responsible for various significant crop losses, which require taking integrated control measures. The present study aimed to identify a possible sustainable approach to the management of Meloidogyne javanica in vegetable crops using an organic compound based on pequi (Caryocar brasiliense) fruit residues. A pot experiment was conducted using cultivars of tomato and lettuce susceptible to M. javanica, with three amendments including inorganic fertiliser, cattle manure and five doses of organic compost with pequi residues. All treatments were inoculated with second-stage juveniles of M. javanica to simulate the root-knot nematode disease in field conditions. Increasing doses of organic compost with pequi residues from 5 kg m-3 to 30 kg m-3 promoted a significant decrease in the nematode population in both cultures evaluated. Organic compost (30 kg m-3) reduced the numbers of galls and eggs of M. javanica by 41.6 and 46.5% in tomato roots, and by 80.3 and 59.2% in lettuce roots, respectively, compared with non-treated control. Organic compost also increased crop development considerably. In general, there was a 43.0% increase in plant development compared to non-treated control. Hence, organic compost of pequi residues could be an alternative to toxic chemical nematicides and recommended as eco-friendly management of M. javanica in vegetable crops. Federal University of Lavras (UFLA) Department of Plant Pathology, Lavras - MG Montes Claros State University (Unimontes) Center of Agricultural Sciences, Janaúba - MG São Paulo State University (UNESP/FCA) Department of Plant Protection, Botucatu - SP São Paulo State University (UNESP/FCA) Department of Plant Protection, Botucatu - SP

The umbuzeiro is a native Brazilian semi-arid plant with great agroindustrial potential. The characterization of the fruit, as well as the development or improvement of technologies for value aggregation are fundamental for its conservation, dissemination and culinary expansion. The objective was to characterize physically and chemically fruits of umbu and to define the access with greater commercial potential. A completely randomized design was used, with 10 replications, in a total of 4 accessions of umbuzeiro. The fruits were selected prioritizing uniformity of fruit size and maturation stage. Fruit peel color was analyzed; diameter and length; mass of the fruit, the bark, the pulp and the seed; firmness of the fruit, soluble solids contents; pH; titratable acidity and solids/acidity ratio. The values of the pulp yield and the technological index were determined. Significance was verified for all variables, except for soluble solids and pH. The average value of the titratable acidity was 1.3 mg of citric acid 100 mL-1 of juice. The diameter of the fruits varied between 4.0 and 4.5 cm. Fruit mass varied from 33.00 to 43.62 g and access to EPAMIG-C06 was the heaviest. The accesses EPAMIG-C06 and EPAMIG-C18 presented the highest technological index. Based on the results, it was concluded that the accesses present potential to the pulp industry due to the size and characteristics of the fruits. The umbu accesses under study presented small variation for solubility and pH. For in natura consumption and/or processing, the access EPAMIG-C06 stands out due to attributes of commercial interest.

RESUMO: Agentes de controle biológico associados com matéria orgânica é uma estratégia que pode potencializar o controle dos nematoides-das-galhas. Objetivou-se neste trabalho avaliar o efeito de materiais orgânicos e rizobactérias sobre Meloidogyne javanica em tomateiro. Utilizou-se o delineamento em blocos casualizados, em esquema fatorial 4x2+1, sendo quatro materiais orgânicos (turfa, biofertilizante, esterco bovino e composto orgânico de casca de pequi), dois isolados de rizobactérias (Bacillus pumilus -1 e B. pumilus - 76) e adubação mineral (tratamento adicional), com oito repetições. Mudas de tomateiro foram transplantadas para vasos contendo solo arenoso, ao qual incorporaram-se os diferentes materiais orgânicos. As suspensões das rizobactérias (OD 540=0,5) foram aplicadas ao solo via rega. O solo de cada vaso foi infestado com aproximadamente 3000 ovos e eventuais juvenis de segundo estádio de M. javanica. Todos os materiais orgânicos associados às rizobactérias reduziram o número de galhas e massas de ovos de M. javanica em comparação à adubação mineral. Já o número de juvenis (J2) foi menor nas combinações pequi + B. pumilus-1 e B. pumilus-76 e turfa + B. pumilus-1. O número de ovos e o fator de reprodução foram influenciados pela interação entre as rizobactérias e os compostos. Para o composto de pequi, B. pumilus-1 promoveu menor número de ovos por grama de raiz, enquanto para turfa, B. pumilus-76 foi a mais eficiente. Para o fator de reprodução, apenas o esterco foi influenciado pela bactéria, sendo que B. pumilus-1 foi a que proporcionou menor capacidade reprodutiva do nematoide. ABSTRACT: Biological control agents associated with organic matter is a strategy that can enhance the control of root-knot nematode. The objective of this study was to evaluate the effect of organic materials and rhizobacteria on Meloidogyne javanica on tomato. We used the randomized block design, in a 4x2+1 factorial scheme, four organic materials (peat, bio-fertilizer, manure and organic compound of pequi hulls), two isolates of rhizobacteria (Bacillus pumilus-1 and B. pumilus-76) and mineral fertilization alone (additional treatment), with eight replications. Tomato seedlings were transplanted to pots containing sandy soil, in which the different organic materials were incorporated. Suspensions of rhizobacteria (OD 540=0,5) were applied to soil by means of irrigation. The soil in each pot was infested with approximately 3,000 eggs and eventual second stage juveniles (J2) of M. javanica. All organic materials associated with rhizobacteria reduced the number of galls and masses of M. javanica eggs compared to mineral fertilizer. The number of juveniles (J2) was lower in combinations pequi + B. pumilus-1 and B. pumilus-76 and peat + B. pumilus-1. The number of eggs and the reproduction factor were influenced by the interaction between rhizobacteria and organic materials. For the compound of pequi, B. pumilus-1 produced a lower number of eggs per gram of root, while for peat, B. pumilus-76 was the most efficient. For the reproduction factor, only the manure was influenced by the bacterium, and B. pumilus-1 was the one that provided lower reproductive capacity of the nematode.

The effects of treating seeds of the common bean with rhizobacteria before sowing associated with different nitrogen (N) doses on the control of the nematode Meloidogyne javanica was evaluated. The assay was carried out in a greenhouse in random blocks, with a factorial arrangement of 5 × 5 + 1: five N doses (0, 25, 50, 100, and 200 kg/ha); five isolates: Bacillus pumilus (1, 60 and 76), Bacillus subtilis.-34, Bacillus sp.-36, and one control treatment. The plants were inoculated with 3,000 nematode eggs/pot. After 60 days the assay was evaluated. In the absence of N, B. pumilus-60 promoted a reduction of more than 50% in the number of galls and egg masses compared to the control. B. pumilus (1 and 76) and Bacillus sp.-36 reduced the number of galls in combination with increased N doses. Treatment of seeds with Bacillus in combination with N fertilization contributed to a reduction in the number of galls and nematode egg masses. B. pumilus (60 and 76) reduced the number of galls and egg masses in the absence of N, indicating a nematicidal effect. The treatments had no effect on the number of second-stage juveniles, eggs, or the plant parameters.

Pequi waste added to soil can lead to promising results in the management of plant nematodes. This study evaluated the effect of organic compost of pequi fruit waste in the control of Meloidogyne javanica in okra plants. The compost was comprised of cattle manure, sugarcane straw, and pequi rind waste in the ratio 1:1:1. Treatments were five doses of organic compost (0, 5, 10, 20, and 30 g dm-3) and two additional controls: manure (20 g dm-3) and mineral fertilizer (100 mg dm-3 of N), arranged in randomized block design with 10 repetitions. Different treatments were incorporated into pots containing 3 dm-3 of sandy soil infested with 5,000 eggs of M. javanica. Seedlings were transplanted five days later, and evaluated after 60 days of transplanting. Organic compost with pequi waste incorporated to soil increased shoot dry weight and root weight, and reduced the number of egg masses, galls and eggs of M. javanica per gram of root, and reproduction factor. Doses of 20 and 30 g dm-3 increased plant development and reduced the reproductivity of M. javanica compared to mineral fertilizer.