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Pineapple can be affected by fruit collapse, a disease caused by the bacterium Dickeya zeae. However, adequate fertilization can increase the fruit’s resistance to this illness. Therefore, the impact of preharvest foliar calcium and silicon fertilization on pineapple quality and fruit collapse incidence was assessed in this study. The experiment implemented a split-plot design with two factors. The first factor has two terms of inoculation (flower induction and before harvest). The second factor uses a control with three foliar fertilization treatments, A (control: No foliar fertilizers applied), B (Ca from 13 to 11 weeks before harvest/from 6 weeks to harvest), C (Si from 13 to 11 weeks before harvest/from 6 weeks to harvest), and D (Ca + Si from 13 to 11 weeks before harvest/from 6 weeks to harvest). Treatment D gave the best response. It had the lowest fruit collapse incidence (21.70%), highest ascorbic acid (71.64 mg/kg), elevated β-carotene (4.87 mg/kg) and mineral content (Ca: 1851.10 mg/kg, Si: 1164.87 mg/kg), essentially under the before harvest term of inoculation, which was more harmful for the fruit. In conclusion, mixed foliar calcium and silicon fertilization manage to improve the tolerance to fruit collapse incidence, impacting the pineapple quality positively

Fusarium oxysporum f.sp capsici, which causes chili-fusarium wilt disease, may be regulated by a secondary metabolite of Trichoderma harzainum. Effervescent tablets are used because liquid formulations have some drawbacks. The purpose of this study is to qualitatively determine T. harzianum’s best crude secondary metabolites, growth and yield, and phenolic compound content in chili crops in foamed tablet formulations against F. oxysporum in vitro. The in vitro study used 6 replicates, a completely randomized design, and 4 treatments consisted of controls and 4, 6, and 8 tablets. Under in vivo conditions, the experiment used a randomized block designs with 4 replicates, eight treatments consisting of controls, fungicides (benomyl), and four, six, or eight tablets per day before or after inoculation. The variables observed were antagonist testing, incubation time, disease intensity, disease incidence, AUDPC, germination rate, plant height, root fresh weight, and qualitative phenolic composition. The results of the study showed that the best dose of T. harzianum’s crude secondary metabolite in vitro was 4 tablets. Medications in in-plant studies delayed the incubation period by 64.11%, suppressed disease outbreaks by 58.34%, reduced disease intensity by 80.45%, increased plant height by 50.4%, and harvested phenols (saponins, tannins, hydroquinone). The content of the compound has been qualitatively increased.

This research aims to determine the best pH media for the production of Pseudomonas fluorescens P20 raw secondary metabolites, its effect on controlling damping-off, and on cucumber seedling growth. In vitro test uses completely randomized design with four replicates and seven treatments consisted of pH 5.0; 5.5; 6.0; 6.5; 7.0; 7.5; and 8.0. In planta test uses a randomized block design with three replicates and ten treatments consisting of control, mancozeb 80%, and raw secondary metabolites with pH 7.0 and 7.5, and 4 concentration levels, i.e., 5, 10, 15, and 20%. Variables observe population density, inhibition ability, protease and chitinase qualitatively, germination ability, incubation period, disease incidence, the area under disease progress curve (AUDPC), crop height, number of leaves, root length, and crop fresh weight. The result shows that the best pH for the production of raw secondary metabolites is 7.0, indicated by population density as 5.68 × 1024 cfu/ml, inhibition ability as 50.8%, and the best protease and chitinase qualitatively. Application of the secondary metabolites on pH 7.0 could suppress disease intensity, incubation period, and AUDPC as 66.67, 77%, and 0%-day, respectively, and increase crop height, the number of leaves, root length, and crop fresh weight as 57.65, 37.19, 63, and 74%, respectively.

Ralstonia solanacearum is the most devastating bacteria. Pseudomonas fluorescens P60 is a bacterial antagonist. This research aimed to study shelf life, antagonism and the effect of granular application of P. fluorescens P60 to control bacterial wilt and growth of tomato in planta. The research was conducted at the Plant Protection Laboratory and the screen house, Faculty of Agriculture, Jenderal Soedirman University, from October 2018 to March 2019. A randomized block design was used with six treatments and five replicates. The treatments were control, R. solanacearum + 1, 5, 10, and 15 g the granule, and bactericide (Agrimycine sulfate 20%). Variables observed were population density, clear zone, incubation period, disease incidence, disease intensity, area under disease progress curve (AUDPC), crop height, root length, crops fresh weights, and phenolic compound content qualitatively. Result showed that the formulation up to 10 weeks still performed a high P. fluorescens P60 population and good activity. All the granular and the bactericide effectively suppressed the disease indicated by the lenghtening incubation period of 22.77-26.25%, reducing the disease incidence as 60-85%, decreasing disease intensity as 65-85%, and decreasing AUDPC as 75.69-86.11%-days, increasing phenolic compound content qualitatively, and increasing crop height between 24.85-36.17%, and fresh weight between 46.04-57.13%.

Cacao pod rot caused by Phytophthora palmivora, is an important disease and contributes significant disease losses to global cocoa production. This research objective was to determine the effect of Trichoderma harzianum and T. virens suspensions to cacao pod rot disease on the field. This research was carried out in Pulo Hagu village, Pidie Regency, Aceh, Indonesia from March to July 2017. The single pattern randomized block design was adopted to evaluate three treatments, i.e. without suspension (control), suspensions of T. Harzianum, and T. virens for eight replications. Each replication consisted of three of experimental units. The result showed that both of Trichoderma species contained only Alkaloid metabolite based on Phytochemical test. On the field, the application of T. harzianum suspension reduced the percentage of fruit infection and disease intensity for 48.57 %, 46.04 % at 12 weeks after application (WAA) respectively. Based on the percentage reduction in the area of the spot between the metabolites T. harzianum suspension and control and T. virens and control are 47.24 % and 27.46 % at 87 WAA respectively. In addition, T. virens suppressed the percentage of infected fruit and the intensity of infected fruit for 40.61 % and 38.02 % at 12 WAA.

This research aimed to study the compatibility of some Trichoderma spp. isolates on some synthetic chemical pesticides carried out at the Laboratory of Plant Protection, Faculty of Agriculture, Jenderal Soedirman University from April up to July 2014. Trichoderma isolates were derived from rhizosphere exploration on ginger, banana, pineapple and shallot. The synthetic pesticides used were mancozeb and propineb (fungicides), oxytetracycline and streptomycin sulfate (agrimycin, bactericides), carbofuran (nematicide), and deltamethrin and prefenophos (insecticides: synthetic pyrethroids and chiral organophosphates, respectively). The compatibility test used food poisoning method in a completely randomized design with three replicates. Variables observed were discolouration, sporulation, colony diameter, conidia density, and fungal growth at pesticides treatment. The data were analyzed by F test at 5 % significant level and continued by Duncan Multiple Range Test (DMRT) when there was a significant difference. The result of the research showed that the most significant decreasing of Trichoderma spp. was found on mancozeb for shallot, ginger, and banana isolates, and propineb for pineapple isolate, respectively, 89.4, 97.7, 93.3, and 95.2 %. This result was in line with colour, sporulation, and inhibition level observation.

The research objective was to know ability of antagonistic microbes to control bacterial wilt on potato in the field. This research was carried out at Serang Village, Karangreja Subdistrict, Purbalingga Regency from June up to August 2012. The antagonist, originally isolated from potato field, was Bacillus sp. B2 and B4, and Pseudomonas sp. P19 and P20. Based on the research result, Pseudomonas P19 could control the disease on potato with delaying incubation period of 78.95%, suppressing disease intensity of 51.57%, decreasing final pathogenic population of 99.74%, and inducing plant resistance with increasing saponin, tannin, and glycoside content. However, the antagonist could not increase growth and yield of potato.