Organic fertilizer decomposed with biofilm biofertilizer to nutrients status and yield of shallot on acid and alkaline soil

. The use of organic fertilizer in organic farming increases carbon sequestration so will reduce CO 2 concentration in the atmosphere and impact of global warming. Research aims to study the effect of biofilm biofertilizer (BiO 2 ) formulas and organic fertilizer dosages on soil nutrients status and shallot yield in acid (Alfisol) and alkaline (Vertisol), Experiment was conducted in field with two treatment factors says BiO 2 formula (F 0 , F 1 , F 2 , and F 3 ) and doses of organic fertilizer composted with biofilm biofertilizers i.e 0, 10 and 20 tonha -1 (D 0 , D 10 , and D 20 ). As a comparison treatment was NPK at a rate of 200 kg urea, 200 kg ZA, 400 kg SP-36 and 250 kg KCl per hectare). The observed variables include available-P, exchangeable-K and shallot bulb weights. Data analyzed by ANOVA followed by DMRT at 95% level confidence. The dose of organic fertilizer increased significantly of observed variables, while the formula of BiO 2 was not. The application of organic fertilizer at 20 tonha -1 increased available-P, exchangeable-K and weight of shallot bulbs on Vertisols and Alfisols. Compared to the NPK fertilizer treatment, the application of 20 tonha -1 organic fertilizer provided higher shallot yield on Alfisol soil but lower on Vertisol soil. It need further reseacr to identified the factor causing lower yield on Vertisol.


Introduction
The successful integration of a consortium of functional rhizobiota that provide nutrients and biological agents that prevent soil-borne diseases (basal root rot) into biofilm biofertilizer formula that effectively provides nutrients and prevents moler disease attacks in the previous research [17 -19] has become the basis for further development of the BiO2, which is more consistent in its ability to be used in the field.There were two formula of biofilm biofertilizer which have similar effectivity in the previous research.Field testing will verify which formulas have consistent performance and also which treatments can optimize their performance.
Combining microbes and organic materials in one fertilizer formula will bring the microbes closer to the nutrients they need so that they are better able to develop and be active in the soil.The research that has been carried out has succeeded in combining the Psolubilizing fungus Aspergillus niger and the sulfur-oxidizing fungus Penicillium nalgiovensis together with natural phosphate powder, sulfur and organic materials in one biosulfo fertilizer formula which is able to increase the available P and S simultaneously so that it can increase shallot yields on three types of soil.namely those with acidic, neutral and alkaline reactions [1,2].Combining functional microbes that provide nutrients and biological agents in one biological fertilizer formula (biofertilizer) is thought to better ensure their growth and activity in the plant root environment, forming a microbial biofilm so as to better guarantee their performance in increasing nutrient availability and uptake by plants and preventing the development of microbes that cause infectious diseases.land.Various countries have succeeded in developing and utilizing biofertilizers and biopesticides.to increase fertilizer efficiency, increase crop yields, preserve natural resources and food security [4,5,6].According to [7,8] biofilm is a complex community of various microbial species attached to or close to plant roots.This biofilm can be developed in vitro and at high cell density can be used as a biofertilizer or biocontrol agent in plants.
The inclusion of functional microbes that provide nutrients and biological agents that prevent soil-borne diseases in a fertilizer formula is intended to bring it closer to the nutrients needed so that after being given to the soil it will adapt more quickly and develop into a dominant microbial community in the rhizosphere environment, forming a microbial biofilm that will increase the availability of nutrients and their uptake by plants and prevent the development of disease-causing microbes.Biofilm is a form of association of various microbial species which is believed to have a greater ability to increase nutrient availability, produce growth factors and resist plant disease attacks compared to monoculture or polyculture populations that do not form biofilms [6, 7 9, 10].Biofertilizer biofilm is more resistant to environmental stress, attacks by predators and antagonists and has the ability to increase crop yields higher than conventional biofertilizers (monoculture, mono inoculums).For example, in rice plants the increase in dry weight of stover by conventional biofertilizer was only 7% and biofilm biofertilizer was 25% compared to control, and biofilm biofertilizer + ½ dose of recommended fertilizer increased 55% from treatment with full doses of NPK fertilization.Existing research results show the advantages of biofertilizer microbes that form biofilms compared to those that do not form biofilms, both in increasing nutrient availability, production of growth-promoting substances (eg IAA) and their role in preventing plant disease attacks [11,12,9,13,14,15,7,6,10,16].
This research is a follow-up to the results of the previous research to verify, optimize and select the best formula, as well as to identify factors that become weaknesses of the 'initial' formula of BiO 2 fertilizer in field so that the quality can be improved.From this research, a 'selected' BiO2 fertilizer formula will be obtained which can be developed as a BiO2 fertilizer product that is ready for use by farmers.

Material and method
The experiment aims to study and determine the combination of organic material dose treatment and the 'initial' formula for biofilm bio-fertilizer with biological agents which has the highest performance in supporting plant growth, preventing basal root rot attacks and providing shallot yields on acidic and alkaline soils to be selected as the 'selected formula'.'BiO2.The experiment was arranged in a randomized completely block design (RCBD) with the experimental treatment plan as shown in the Table 1 : Each treatment combination was repeated three times.The variables observed included plant growth and yield as well as the availability of N, P, K and S nutrients, pH and soil organic matter.Data were analyzed using the F test at a confidence level of 95% followed by Duncan's multiple range test if there was a significant effect.

Results and discussion
Shallots require soil with a crumb structure, medium to clay texture, good drainage/aeration, contains sufficient organic matter, and the soil reaction is not acidic (soil pH: 5.6 -6.5).The most suitable soil for shallots is alluvial soil or its combination with Glei-Humus or Latosol soil.Soil that is sufficiently moist and water does not stagnate is favored by shallot plants.
As shown in the Table 2, the Alfisols soil used has a pH of 5.98 (slightly acidic).The C-organic content is 0.07% (very low).The nutrient content of Alfisols is very low, both total and available.Total N is 0.38% (medium).Total P in alfisols soil is 0.08%, which is very low, with available P content analyzed using the Bray method of 0.12 ppm.The total K content was 1.131%, available K was 0.102% (moderate), total S was 15.964 ppm, and water-soluble S was 0.16 ppm (low).
Meanwhile the Vertisols soil used has a loamy loam texture.The pH of Vertisols soil is 7.49, which is slightly alkaline.The total N content in vertisols soil is 0.46%, which is low.The total P in the vertisols soil was 1.212% and the available P was 3.26 ppm, which was very low.The total S value content of vertisols soil is 101.23%, and the available S or water-soluble S is 0.17 ppm, which is low.

Treatment factor
Soil pH characteristic BiO2 Formula Dosages of organic fertilizer, tonha -1 acidic alkaline  The use of organic fertilizer at a dose of 20 tonha -1 provides plant growth as indicated by plant height (Fig. 5 and 6) that is not significantly different to the treatment using NPK fertilizer (200 kg urea, 200 kg ZA, 400 kg SP-36 and 250 kg KCl per hectare).This shows that at these dose (20 tonha -1 ), organic fertilizers is able to meet the nutrient needs of shallot equivalent to the nutrient provided by chemical NPK fertilizers.This can be shown by the higher soil available-P and exchangeable-K of organic fertilizer treatment (20 tonha -1 ) compared to the treatment using NPK fertilizer (Fig. 1, 2, 3 and 4).
Beside provide plant nutrient, organic fertilizer improve soil physical, chemical and biologial properties to support plant growth better than chemical fertilizer.The increase of organic fertilizer dose will increase nutrient available to plant.Both soil available-P (Fig. 1) as well as soil exchangeable-K (Fig. 2) are increase linearly with the increasing of organic fertilizer doses used.In alkaline soil, phosphorus often fixed by calsium and magnesium that make it not available to the plant.While in acid soil P can be fixed by aluminium and iron that make it low availability to the plant.The use of organic fertilizer will improve soil microbial activity and produce organic acid which will increase soil pH and chelating Al and Fe in acid soil or reduce pH and chelating Ca and Mg in alkaline.This will increase soil available-P in acid or in alkaline soil.
Just like soil available-P, the increase of organic fertilizer dose increase exchangeable-K as shown in Fig. 3 and 4. Soil exch-K increase linearly with the increase of organic fertilizer dose.Potassium is the essential nutrient for plant including shallot.It need to fill the sitoplasms, to keep cell turgor and rigidity so it is important to plant resistance againt pest and diseases.Both in Vertisol and Alfisol soil, the availability of soil P and K was higher for the organic fertilizer treatment than for NPK fertilizer treatment.This maybe caused of the high content of K of the organic fertilizer Plant need nutrient and other factor for their growth.Shallot is one of the high economic value horticulture that need high available soil nutrients especially macro nutrient such N, P and K to growth and give optimal yield.From the Fig. 5 and 6 can be shown that the use of organic fertilizer decomposed with biofilm biofertilizer (BiO2) can provide P and K for shallot growth as well as NPK fertilizer does as indicated by the plant height for the organic fertilizer treatment was slightly higher than NPK fertilizer treatment.Plant yields are generally in accordance with plant growth.This also tend to happens to the yield of shallot bulbs on Vertisol and Alfisol soils as shown in Fig. 7 and 8. Increasing the dose of organic fertilizer increases the yield of shallot bulbs, except at a dose of 20 tonha -1 with formulas F2 and F3 on Vertisol soil which reach the highest (maximum) at a dose of 10 tonha -1 .This can occur because at a dose of 10 tonha -1 the organic fertilizer used is already able to meet the needs of plants.At a dose of 20 tonha -1 , there was a decrease in F2 and F3 treatment, it is suspected that there were certain nutrients outside of P and K or decomposition results that caused plant growth to be hampered.NPK fertilizer at recommendations dosage provide the highest yields.It mean that there is something that not yet known in this research that make the shallot yield tend to decrease with higher dose than 20 tonha -1 .Different result from Alfisol soil, which show higher yield of organic fertilizer treatment than NPK fertilizer as shown in Fig. 8.In Alfisol soil, the yield of shallot bulbs in the treatment with an organic fertilizer dose of 20 tonha-1 gave higher shallot yields compared to the recommended dose of NPK fertilizer treatment, allegedly due to the physical-chemical-biological properties of the soil which became better after applying organic fertilizer, when compared to the effects application of NPK fertilizer.This can happen because the presence of organic and microbial material from biofertilizer biofilms which is more effective than conventional biofertilizers can improve the physical-chemical properties of the soil much better because its ability to provide nutrients, produce growth-promoting substances and stimulate soil aggregation can be much higher [7,[9][10][11][12][13][14][15][16].

Conclusion
1.The dose of organic fertilizer affect significantly to the available-P, exchangeable-K, plant height and shallot yields, but the BiO2 fertilizer formula does not.The use of organic fertilizer decomposed with biofilm biofertilizers at the dose of 20 tonha -1   Bulb fresh weight, gplant -1 Treatment combination provides higher av-P, Exch-K and shallot yields than NPK fertilizer treatment (200 kg urea, 200 kg ZA, 400 kg SP-36 and 250 kg KCl per hectare).2. The used of organic fertilizer decomposed with Formula BiO2 1 (F1) is not in optimal dose yet as shown by the plant yield which is still increasing linearly.Meanwhile, for organic fertilizer decomposed with the BiO 2 2 (F 2 ) and BiO 2 3 (F 3 ) formulas, the optimal dose is 10 tons per hectare.Lower yields from the NPK treatment may becaused of low nutrients content that could not provided plant nutrients demand optimally for crop production.
This research publication is supported by the Research Group Grant scheme (HGR-UNS Research) A for the 2023 fiscal year with the contract number 228/UN27.22/PT.01.03/2023.

Fig. 1 .
Fig.1.The influence of the treatment on available-P of Vertisol soil.

Fig. 2 .
Fig. 2. The influence of the treatment on available-P of Alfisol soil.

Fig. 3 .
Fig. 3.The influence of the treatment on exchangeable-K of Vertisol soil.

Fig. 4 .
Fig. 4. The influence of the treatment on exchangeable-K of Alfisol soil.

Fig. 5 .
Fig. 5.The influence of the treatment on shallot height at Vertisol soil

Fig. 6 .
Fig. 6.The influence of the treatment on shallot height at Alfisol soil

Fig. 7 .
Fig. 7.The influence of the treatment on shallot yield in Vertisol soil

Fig. 8 .
Fig. 8.The influence of the treatment on shallot yield in Alfisol soil.

Table 1 .
The experimental treatment factors of the research * NPK fertilizer dosage was 200 kg urea, 200 kg ZA, 400 kg SP-36 and 250 kg KCl per hectare

Table 2 .
Some of chemical and physical properties of Alfisol and Vertisol soils used in the experiment