The need to use sugarcane seed under rainfed conditions necessitates studies to achieve agronomically sound production that facilitates increased sprouting and plant population in commercial fields during the spring planting season (January-June) in Cuba. To this end, a control plot was established to determine the impact of three applications of Lebame on the percentage of soluble solids in sugarcane seed plantations under rainfed conditions (certified seed). The study was conducted at the Pablo Noriega Basic Unit of Cooperative Production (UBPC), belonging to the Comandante Manuel Fajardo Agricultural Experiment Station (EAA). The cultivar evaluated was C86-12, planted with 11-month-old sugarcane on red Ferralitic soils. Two treatments were evaluated in May 2026, with refractometric Brix as the variable assessed. Three one-hectare sampling points were selected, and 10 random samples were taken from each point for each treatment. Using the generated data, an analysis of variance was first performed between the combined treatments, comparing means with a multiple range test using Tukey's test (P<0.01 and P<0.05), followed by a student’s t-test at 1% and 5% significance levels. The results showed that the control group, in the variable under study, achieved a 27.6% higher result than the Lebame treatment, indicating a possible delay in sugarcane seed maturity with the application of the bio stimulant.

The rainy season in Cuba is between May and October (Jorge et al., 2023). However, sugarcane cultivation only covers 17% of the irrigated area, meaning that certified seed plantations are mostly under rainfed conditions. This affects seed quality, particularly for plantings from January to June, and is especially acute for long-cycle spring plantings known as "past springs" (May-June). Historically, these plantings must wait for the first rains because the seed plantations have suffered agricultural drought stress from November until the first ten days of May, and the seed is already mature, limiting sprouting and increasing the cost of planting, which is the main investment in the crop. The need to use certified or inspected seed in rainfed sugarcane cultivation necessitates studies that allow us to obtain agronomically sound yields that facilitate increased sprouting and plant population in commercial fields during the spring planting season (January-June) in the country. To date, there is no evidence in Cuba of using domestically produced biostimulants and biofertilizers to treat certified seed under rainfed conditions to delay or mitigate seed maturation, thereby facilitating a higher sprouting rate.

Jorge et al., (2025), in a study of Sugarcane Cultivar Selection under agricultural drought conditions, obtained similar results in the 12-month-old sucker to the 15-month-old plant cane in terms of cane production; however, the percentage of pol in cane was lower in both suckers. The harvest was carried out in the first ten days of December and the rainfall was similar, providing evidence that the results in suckers for the sugar content harvested in the same harvest period offer higher values in the percentage of pol in cane. Among the factors that influence this aspect is that the composition of the stalks is more homogeneous (Delgado, 2022, Jorge et al., 2024). Jorge et al., 2025 attributed this result to the fact that in the shoot strain, an application of the biostimulant Enerplant (dose 5.2 milliliters ha-1) was made to all cultivars under study, at the age of eight months.

Currently, it is necessary to establish agroecological and sustainable agriculture under the existing conditions of Cuban sugarcane farming. This will allow for high plant populations in spring plantings within sugarcane blocks, thereby achieving high sugarcane production per area, which is the variable that most influences sugar production per hectare. Implementing recommendations for the use of bioproducts that delay or reduce seed maturity under rainfed conditions will increase sugar production and reduce the costs of the main investment in this crop (planting), as well as conserve sugarcane agroecosystems. This study (Control Plot) aimed to determine the impact of three applications of Lebame on the percentage of soluble solids (refractometric Brix) in certified seed plantations.

The study was conducted in Block 301 of the Pablo Noriega Basic Unit of Cooperative Production (UBPC) in rainfed areas (certified seed) belonging to the Comandante Manuel Fajardo Sugar Agro-Industrial Company (EAA), Quivicán municipality, Mayabeque province. The cultivar evaluated was C86-12 in the sugarcane rootstock planted on red Ferralitic soils. Two treatments were evaluated: 1-TI - Plantations without the application of bioproducts (control) and 2-TII - Treatment with Lebame at 10 liters/ha (three applications). The first application was carried out 90 days after planting, the second 120 days after planting, and the third sixty days after the second application. The variable evaluated was the percentage of soluble solids in the field (refractometric Brix at the center of the stem). For this purpose, three sampling points of 1 hectare each were selected, and 10 random samples were taken at each point for each treatment.

For the application of the bioproduct, a Matabi manual sprayer (backpack) with a 16-liter capacity and flood jet nozzles (in bands over the furrow) was used with a final calibrated solution of 200 L ha-1. Applications were always made in the morning. The evaluation was carried out on May 18, 2026, at 11 months of age. With the information generated, an analysis of variance was first performed between the combined treatments with the comparison of means using Multiple Range test, using Tukey's test (P<0>

Characteristics Of the Bioproduct Used in the Study Lebame

LEBAME is a product of ICIDCA [Efficient Microorganisms], a plant growth biostimulant produced biotechnologically. It consists of the microorganisms: Bacillus subtilis B/23–45–10 Nato, Lactobacillus bulgaricum B/103–4–1, and Saccharomyces cerevisiae L–25–7–12. It is produced from an inoculum of these microorganisms, with sugarcane molasses and ammonium sulfate through a fermentation process. This product is proposed to increase crop growth, quality, and productivity, as well as photosynthetic capacity, through enhanced leaf development. It promotes flowering, fruiting, and ripening through its hormonal effects in meristematic zones. It also generates a mechanism for suppressing insects and diseases in plants (ICIDCA, 2021).

The analysis of variance showed highly significant differences between treatments for the variable under study (Table 1), which was reflected in Figure 1 where the control outperformed the treatment where Lebame was applied. Similar results were obtained in Table 2 (Student's t-test), indicating a possible delaying effect of the biostimulant with three applications on sugarcane maturity. This may be because this product increases crop growth (ICIDCA 2021), and it also corroborates the deductions made by Jorge et al. (2025).

It is worth noting that both treatments have acceptable Brix values for use as seed, as the control reached soluble solids percentages below 19%, which is feasible. This could have been caused by pre-harvest rains (March, April, and May) exceeding 160 mm during the period (Table 3). However, a relevant factor is that the treatment with Biostimulant achieved a percentage 27.6% lower than the control. The above highlights the need to continue exploring this issue in order to offer a possible solution for certified sugarcane seed in Cuba for spring plantings (January–June).

Table 1: Results of the analysis of variance between treatments for the field refractometric Brix.

Figure 1: Comparison between treatments in the percentage of soluble solids (refractometric Brix)

Table 2: Results of the t-student test between treatments for the field refractometric Brix

Table 3: Rainfall reported during the study period

1-The use of the Lebame biostimulant (three applications) on certified sugarcane seed showed a possible delay in maturity.

1.Continue exploring the application of biostimulants to delay the maturity of certified sugarcane seed as a possible solution for spring plantings (January – June) in the country.