Viabilitas kombinasi bakteri dan cendawan pada berbagai komposisi bahan pembawa dan efektifitasnya dalam mendekomposisi biomas jagung

Abstract

One alternative to accelerate the decomposition of lignin or cellulose organic matter is to use microorganisms. To ensure the viability and effectiveness of the decomposer microorganisms a suitable carrier material is required. The objective of this study were to obtain a combination of microorganisms isolates (bacteria and fungi) in accordance with the formulation of the carrier in supporting their viability and effectiveness to decompost of maize biomass. The experiment was carried out on February to November 2016. The treatment consisted of two factors, namely the carrier and microorganism. The tested of cerrier are: (1) water immersion of rice and zeolite, (2) soymilk and soaked water, (3) clay of soil and cassava fermentation, and (4) sago and compost. The microorganisms used were two isolates of bacteria and fungi, ie: (1) combination of E7.7 bacteria and P7 fungi and (2) bacteria combination B7.1 and fungus O5. The results showed that the combination of isolates E7.7 + P7 and B7.1 + O5 up to 28 weeks' storage were relatively superior than Promi and EM4. At 28 weeks storage, population of bacterial E7.7 + P7 is 2,1-2,75 x 10 9 cfu/g and fungus 0,30-0,48 x 10 9 cfu/g. Isolate B7.1 + O5 had bacterial 1,38-2,5 x 10 9 cfu/g and fungus 0,2-0,3 x 10 9 cfu/g. While Promi and EM4 had bacterial were about 0.1-1.5 x 10 9 cfu/g and fungus 0.1 x 10 9 cfu/g. Both of these isolate to decomposition of maize biomass had lower C/N and water content, and higher P and K content than EM4. Therefore, both of the combination of bacteria and fungi are worthy as biodecomposer for the making of compost fertilizer. To maintain viability and effectiveness of microbe E7.7 + P7 was a better to use sago + compost, while for the combination of B7.1 + O5 can using sago + compost and alternative is water immersion of rice + zeolit carrier material. The results of identification based on 16S rRNA sequence showed that isolates B7.1 and E7.7, respectively were Bacillus cereus strain ATCC14579 and Brevundimonas diminuta strain NBRC12967. While isolates of fungus O5 and P7 respectively were are Aspergillus fumigatus strains KARVSO4, and A. fumigatus strains DAOM-21534-28S.

Biocontrol activity of endophytic bacteria from cocoa against Phytophthora sp. and Colletotrichum sp.

“…Antagonistic microorganisms that act as pathogenic biocontrol agents utilize mechanisms such as competition, parasitism, antibiosis, or induction resistance to inhibit the growth of pathogens (Djaenuddin, 2016). This finding is supported by other literature where endophytic bacterial isolates can produce secondary metabolite compounds such as antibiotics, antifungals, HCN, and cell walldegrading enzymes to inhibit the growth of pathogens (Widiantini et al, 2020).…”

Controlling of downy mildew on maize using a combination of varieties and mycorrhizae

“…In plant management using biological agents, the induction of resistance and varietal resistance properties can be the main obstacle to the development of pathogens to cause disease [7,10,12]. Each variety has a different level of resistance to pathogens [1,8]. Induction of resistance arises due to the interaction of pathogen, host, and environment [7,25].…”

“…Resistance properties can be enhanced through elicitor-induced induction by involving the coordination and expression of certain genes characterized by the accumulation of certain compounds such as salicylic acid, jasmonic acid and ethylene as well as the expression of proteins related to pathogen pathogenesis [6,7]. Induction by elicitor can also be carried out using microorganisms with special characteristics, such as endophytic microbes, philosphere microbes, nonpathogenic microbes, antagonistic microbes, and plant growth-promoting microbes such as PGPR, PGPF, and mycorrhizal fungi [8][9][10].…”