Number of Leaves
There was no interaction effect between the husk charcoal dose and the bacterial consortium application. The application of husk charcoal and the bacterial consortium had no significant impact on the number of leaves observed 7, 14, 21, 28 and 35 days after application (DAA, presented in Table 1).
Plant height
There was no interaction effect between the husk charcoal dose and the bacterial consortium application. Providing husk charcoal had no significant effect on plant height. Likewise, the application of bacterial consortium except at the age of 7 days after application (DAA). They are presented in Table 2.
Stem diameter
There was no interaction effect between the husk charcoal dose and the bacterial consortium application. As presented in Table 3, the provision of husk charcoal and the bacterial consortium had no significant impact on the stem diameter of corn plants.
Cob diameter, cob length and disease incidence
Charcoal husk treatment without bacterial consortium did not affect cob diameter and length. This is in line with the percentage of disease incidence (%). disease incidence occurred in the rice husk charcoal treatment alone without the bacterial consortium. The intensity of the attack reaches more than 90% at the age of the plant 70 days after application. The lowest intensity of attack was in the combination treatment of 15 tons of husk charcoal per hectare and bacterial consortium by foliar and soil spraying. In treatments that were attacked earlier, namely, in treatments without the addition of bacterial consortia, no cobs were produced. This is presented in Table 4 and Fig 1.
The performance of corn plants given rice husk charcoal and bacterial consortium showed a lower attack level than those given rice husk charcoal alone. This has an impact on crop yields. Giving husk charcoal can bind nutrients well to encourage plant growth. Adding husk charcoal to soil media can improve the porosity of soil media, so it is suitable for root respiration and soil moisture
(Asfar et al., 2021). According to
(Syamsafitri et al., 2023) nutrient content on rice husk charcoal includes several components namely SiO
2 (52 Percent), C (31 Percent), K (0.3 Percent), N (0.18 Percent), F (0.08 Percent) and calcium (0.14 Percent, besides that there are also other components such as Fe
2O
3, K
2O, MgO, CaO, Mn and Cu in small quantities. Besides that, rice husk charcoal can maintain environmental conditions and improve the physical properties of the soil, making the water-holding capacity high so that vegetative growth is a better corn crop. The application of rice husk charcoal to the soil, besides being able to be light and high porosity, the soil remains loose, retains soil moistureand stores components nutrients, driving the growth of organisms that are useful for plants and as component anchors nutrient crops when plants are deficient nutrientand husk charcoal is referred to as fertilizer slow release (
Bayu Murti Petrus et al., 2020). The ability of the silica component contained in the husk charcoal. The presence of Sufficient silica in the soil can help plants to be more resistant to component imbalances nutrients
, which include excess N, deficiency and abundance of Pand poisoning of Na, Fe, Mn and Al
(Katz et al., 2021).
The resistance level of maize plants treated by the bacterial consortium also indicated that the intensity of the attack by the pathogen
Peronosclerospora was low. This is because the bacterial consortium, when formulated, has a disease control mechanism; the treatment of this antagonistic bacterial consortium provides a defense system (bioprotectant) because these bacteria can secrete antibiosis compounds which can encourage attacked plants to fight pathogens
(Mugiastuti et al., 2023). This bacterium is thought to be able to produce compounds, such as antibiotic compounds, siderophoresand other secondary metabolites whose properties can slow down fungal activity. Inhibition of pathogens, namely bacteria, can fight against the invasion of phytopathogens by producing siderophores. Siderophore is an iron chelating compound or Fe3+ complex made by microorganisms to hide the iron micronutrient components around the rhizosphere so that pathogenic microorganisms cannot access it
(Pecoraro et al., 2022).
It is suspected that this consortium contains several microorganisms that are good for agriculture to increase the productivity and growth of corn plants. Like (
Miljakoviæ et al., 2024), plant nutrients may also contribute to the higher efficacy of microbial inoculants as well as the growth and development of plants. Moreover, these organisms exhibit the capability to colonize plant roots, providing numerous benefits to their hosts, including the modulation of phytohormone production, enhancement of soil nutrient availabilityand bolstering resistance against pathogens.
Furthermore, their presence minimizes the reliance on chemical fertilizers, mitigates both biotic and abiotic stress factorsand ultimately boosts crop production, as highlighted
(Asghari et al., 2020). Among the microorganisms utilized to augment agricultural productivity are
Azospirillum,
Arthrobacter,
Bacillus,
Burkholderia,
Enterobacter,
Flavobacterium,
Pseudomonas,
Rhizobium,
Frankia,
Klebsiella,
Clostridium,
Trichoderma,
Beauveria,
Serratia and
Streptomyces, as outlined (
Jeane and Dias-filho, 2021).
Nitrogen is a vital macronutrient essential for protein and nucleic acid synthesis. Microorganisms like
Azospirillum, Azotobacter, Achromobacter, Bradyrhizobium, Beijerinckia, Rhizobium, Clostridium, Klebsiella, Anabaena, Nostocand Frankia play a significant role as biological nitrogen fixers, converting atmospheric nitrogen gas (N
2) into ammonia (NH
3)
(Bhat et al., 2019). This bacterial consortium possesses the ability to assimilate nitrogen-fixing microorganisms, facilitating nutrient recycling, particularly for phosphorwiSus (P) and potassium (K), while also stimulating plant growth. The presence of nitrogen (N) and phosphorus (P) components fulfils the nutritional requirements of plants. The P component is essential for plants to affect photosynthesis and determine harvest age.
Throughout the process of seed filling, seeds assimilate nutrients from the leaves and other plant tissues. These acquired nutrients serve as essential components for a multitude of metabolic pathways, encompassing protein synthesis, starch formationand other biochemical processes vital for seed development. Concurrently, seeds undergo notable metabolic transformations, including the activation of enzymes engaged in starch metabolism, facilitating the storage of energy in the form of starch. As seeds reach maturity, there is an increased accumulation of metabolic by products, contributing to the attainment of maximum size and weight in the produced seeds (
Shaw and Cheung, 2021).
The number of leaves and plant height were not affected by those treatments. This is presumably because internal factors influence the number of leaves. In line with research
(Herhandini et al., 2021), the provision of rice husk charcoal and the consortium bacteria does not affect the number of leaves on corn plants because plant leaves are more due to plant genetics. According to (
Jeane and Dias-filho, 2021), components affecting plant growth, the number of leaves is genetically determined by abiotic factors such as soil (nutrients, heavy metals, pH and salinity), water availability, light intensityand temperature can affect plant-microbe interactions, as they can alter plant metabolism, root exudate composition and rhizosphere biology. This is because, if changes in plant exudative patterns occur, the same treatment and the same plant genotype may interact differently.