Application of biostimulant consortium to increase the growth of sugarcane (Var. Cenning) in a dry land

Sugarcane is considered one of the most promising crops. The growth of the crop is affected by photosynthesis and toter and nutrient absorption by plants. Biostimulant is a non-nutrient biomaterial that is proven to improve crop growth. Based on this idea, Biostimulant technology can be used as an alternative to enhance sugarcane growth. This research aimed to assess the Biostimulant consortium (Sucrosin, humic acid, and AM fungal) to improve the growth of the sugarcane var. Cenning in a dry land. The study tested two treatments, i.e., control (standard procedures) and Biostimulant Consortium application. Sucrosin was applied on 1, 3, 4, and 5 months after planting (MAP) by using a foliar spray. Application of mycorrhizal fungi was spread around the roots area of sugarcane crops. In contrast, the application of humic acid was sprayed on the ground as a coating agent for inorganic fertilizers. Coating fertilizer is carried out by mixing a humic acid solution with as much as 1% of the fertilizer. The research showed the treatment of the Biostimulant Consortium yielded significant results in the sugarcane growth compared to the control on 8 MAP. Biostimulant Consortium can improve crop height and stem diameter significantly up to 30-40% compared to control. It indicates that the Biostimulant consortium’s treatment can improve sugarcane’s vegetative growth in s dry land.


1.Introduction
Globally, Indonesia is the largest sugar-importing country.Based on the Ministry of Trade data, the Indonesian raw sugar import allowance is increasing yearly, from 3.1 million tonnes in 2014 to 3.6 million tonnes in 2015.Therefore, the effort to increase national sugar production through extensibility has led to the utilization of marginal land, including dry land [1].The area of dry land for sugarcane currently reaches 171 thousand hectares and is projected to increase to 260 thousand hectares in the year 2050 [2].However, the dry land limits sugarcane growth because of drought stress.Sugarcane crops undergoing drought stress result in suboptimal shoots and other vegetative growth, decreasing sugarcane production per hectare [1].Sugarcane crops in drought stress will cause the shoots and vegetative growth to be sub-optimal and reduce sugarcane production per hectare.
The current effort to improve sugarcane productivity is still focused on fertilizing technology.Therefore, biostimulant technology can be used as an alternative to the present technology.Biostimulant is a small number of organic compounds that can support and improve plant growth.It improves nutrient absorption efficiency and tolerance of abiotic, thus improving production [3].
Biostimulants increased the growth of sugarcane crops, horticulture, and some food crops [4,5,6,7].The Biostimulant in this research is made from extracts of seaweed organic matter.Applying organic biostimulants from seaweed has considerably influenced the growth of sugarcane crops.The use of biostimulants with humic acid and Mycorrhiza increased the vegetative growth of sugarcane, such as height, stem diameter, and plant rooting [8].
Humic acid and Myoriza can increase plant growth.The negative charge in humic acid makes it effective as a macronutrient, micronutrient, and water molecule and also can reduce leaching.It can increase the availability and intake of nutrients for plants [9].Roni and Soedarmaji [10] reported that the administration of humic acid improved the growth and production of tropical kudzu crops.The same research was delivered by [9]; the application of humic acid on corn plants in dry land proved to increase plant growth (weight, height, and nutritional content of fruit).At the same time, Mycorrhiza has been widely reported to be a biological agent functioning to increase the availability of nutrients in soil [11].
Varieties of Cenning used in this research are based on the Decree Release 3679/Kpts/SR.120/11/2010.This variety has potential production of 775 kg/ha with a yield of 10.97%.Cenning has agronomic properties of having the diameter of a medium bar density, suitably developed on the type of alluvial and Mediterranean soil with a very high clay content with enough watering/rainfall.This study aims to justify Biostimulant Consortium Technology (BCT) to increase the vegetative growth of sugarcane crops in a dry land.

Materials and Methods
This field experiment was conducted in Wanayasa, Tegal Regency, Central Java.This activity was conducted in January-September 2019 using the sugar cane varieties Cenning.The BCT consists of Sucrosin, Humacoat (humic acid), and MizaPlus (Mycorrhiza), which is a product of the Indonesian Research Institute of Biotechnology and Bioindustry (IRIBB).
This experiment was conducted by comparing control and BCT treatment plots.Each plot consists of 5 observation plates of 15 meters in length on a 4 ha land area.Each treatment was performed at different times.Sucrosin was applied on 1, 3, 4, and 5 MAP (a month after planting) with foliar spray.The dose of Sucrosin amounted to 375 ml/ha at 3 MAP and 250 ml/ha at 1, 4, and 5 MAP.MizaPlus was applied by spreading around the plant at a 60 kg/ha dose.Humacoat was applied in 2 stages: spray on the soil and coating of inorganic fertilizer.The application of Humacoat spray on the ground is carried out by using the foliar spray at 1 MAP.The Humacoat dose is 6 liters/ha + 200 liters of water.Fertilizer coating was done by mixing inorganic fertilizer with 1% solution Humacoat (Humacoat + urea, 3:2).Fertilizer dose given in plants as much as 800 kg Za + 200 kg SP36 + 200 kg KCL.The observations were carried out at 2, 3, 4, 5, 6, and 8 MAP.The observed parameters consist of the number of plants, the height of the plant, the diameter of the stems, and the number of stem sections.Data on the observation results are analyzed statistically using the Independent sample T-Test.

Results and Discussions
The experimental parameters (vegetative plant) include the number of plants, the plant's height, the stem's diameter, and the number of branches.The observations during 2-6 MAP show that the BCT treatment significantly improves sugarcane growth compared to the control, especially in the number of plants per meter, plant height, and trunk diameter.High Observation of sugarcane crops at the age of 2-6 MAP (Figure 2) showed the treatment of Biostimulant consortium tends to improve the plant height compared to the control.The time of crop two that MAP sugar cane plant is still higher compared to the treatment of a bio-stimulatory consortium.However, when the plant entered the age of 3, high MAP sugarcane plants with a consortium treatment increased by 51% compared to the control.So sugarcane plants with a consortium treatment can be higher than control up to 6 MAP.Stem section numbers observation of sugarcane was newly performed when 4-6 MAP (Figure 3).The sugarcane plant in this experiment began to emerge when plants aged 4 MAP. Figure 3 shows that the BCT treatment has not significantly influenced the addition of the number of sections in the trunk.However, the number of sections on the stem of the control sugarcane plants on the 6 MAP was higher than in the BCT treatment.The time when 4-6 of the land's MAP has a drought to interfere with the growth of sugarcane plants might cause this condition.The diameter of the stem in 4-6 MAP (Figure 4) on the BCT treatment also shows better than the control plants.Stem Diameter can be measured when sugarcane plants have begun to appear on the stem.The sugarcane plant in this experiment began to emerge in 4 MAP.The BCT treatment in 4 MAP can produce a larger diameter than the control, with an increase of 31%.The diameter of the trunk in 5-6 MAP at BCT treatment is still higher than the control plants, but the value of growth was decreased at 4 MAP.A shortage of water due to the drought that influences stem diameter growth may be one of the causes.
The decrease of sugarcane growth in this experiment is both on control and BCT treatment in 4-6 MAP was caused by the drought factor.According to Irianto [1], sugarcane plants in dry land or under drought stress will undergo stunted initial vegetative growth.This initial growth greatly determines further growth and development, including productivity.Generally, sugarcane plants can grow normally when the vegetative growth period (until 6 MAP) gets enough water.However, the BCT treatment can influence the control of observed parameters.It can be the better initial capital plant for the growth and development of advanced sugarcane plants.The final vegetative growth (8 MAP) demonstrates the influence of a significant BCT treatment compared to the control in the number of plants, the diameter of the trunk, and the number of plant sections (Table 1).The significant result indicates that the application of the biostimulant consortium is still able to maintain the growth of sugarcane plants compared to the control at 8 MAP when experiencing drought-bleeding conditions.The increase in the parameter height of the plant was 23%, and the trunk diameter was 9% compared to the control.While the number of segments in the stem had significantly increased, that was 40% compared to the control.The provision of biostimulants that can increase vegetative growth was also expected to improve the harvest of sugarcane crops [4].
Biostimulants that contain a complex mixture of polysaccharides, micronutrients, and regulatory hormones, can positively influence the process of photosynthesis, cell metabolism, nitrogen, sulfur metabolism, and stress drought response [6].Wahyuni et al. [8] reported that a complete biostimulant (phytohormone, humic acid, and Mycorrhiza) could provide better vegetative growth.The application of biostimulants in agricultural activities has a positive impact on plants.The biostimulant application in plants can improve seed germination rates, enhance the mobilization and distribution of nutrients, improve rooting, flowering, fruit, and crop yields, and increase the content of chlorophyll and area of the leaves, as well as increase resistance to biotic and abiotic stress [12].
The application of Humacoat for increasing plant growth includes soil improvement and fertilizer coating.The ability of Humacoat as groundwater is related to the humic acid fraction as a provider of nutrients such as N, P, K, and S into the soil, and also C elements that act as an energy source for microbes.Humacoat ability as a chelator and coating of inorganic fertilizer is related to the content of a negatively charged functional group derived from the H ion dissociation that causes humic acid to have a high ion exchange capacity to bind inorganic fertilizer [13].Alimin [14] reported that additional humic acid as polyelectrolytic macromolecular material with its functional group (-COOH and-OH phenolate and-OH Alcoholic) could provide a complex function with metal ions due to deprotonation at a relatively high pH.It can support humic acid-forming to a complex bond with ions released by inorganic fertilizer (N, P, K), which triggers slow-release fertilizer to be more stable.
The application of MizaPlus plays a role in increasing sugarcane growth in the land because it can improve the rooting condition by the additional Arbuscular Mycorrhiza.Arbuscular Mycorrhiza plays a role in enhancing the root's ability to absorb nutrients from the soil [15].In addition, Ruiz-Lozano and Azcón [16] have also reported that Arbuscular Mycorrhiza could increase crop resistance in drought stress through increased nutrient absorption, transpiration of leaves, and efficiency of water use.

Conclusions
Treatment of the biostimulant consortium (Sucrosin, Humacoat, and MizaPlus) can increase vegetative growths of sugarcane on varieties Cenning for seeds harvest in a dry land, based on parameters trunk diameter, plant height, and sections number with the increase of 9%, 23%, and 40%, respectively against control, at 8 MAP.

3 Figure 1 .
Figure 1.The number of plants per meter of sugarcane on the 2-6 MAP.

Figure 2 .
Figure 2. High observation of sugarcane on the 2-6 MAP.

Figure 3 .
Figure 3.A steam segment of sugarcane on the 4-6 MAP.

Table 1 .
The final vegetative growth of sugarcane on 8 MAP.