INTRODUCTION
Research reasonable
Basil, often referred to as a spice vegetable, plays a crucial role in enhancing the flavor, color, and presentation of dishes, particularly in Vietnamese cuisine While these small vegetables are typically used in modest amounts, their absence can significantly diminish a dish's characteristic taste Beyond their culinary benefits, various types of basil, including sweet basil, lemon basil, and others, also offer notable health benefits, making them a valuable addition to meals.
In recent years, hydroponic methods utilized in greenhouse conditions have emerged as an innovative technique for cultivating fresh vegetables This closed-system approach significantly reduces the risk of insect infestations, leading to a notable decrease in pesticide use Additionally, by using coconut fiber as a substrate instead of traditional soil, plants can effectively avoid the absorption of heavy metals and other harmful toxins, promoting healthier produce.
Hydroponics is an effective method for growing various crops, including basil, but success largely depends on the preparation of an appropriate nutrient solution While many individuals opt to purchase commercially available nutrient solutions, these are often designed for a wide range of crops and may not be effective for basil specifically Additionally, these solutions can be quite expensive, prompting growers to seek more tailored and cost-effective alternatives for optimal basil cultivation.
This article explores the impact of various nutrient solutions on the growth of basil plants using hydroponics It aims to provide insights into effective techniques for cultivating vegetables through hydroponics and offers guidance on creating a homemade nutrient solution tailored for basil.
Research objectives
Studying the effects of different nutrient solutions on growth, yield and qualities of basil plants cultivated by the circulating hydroponic method.
Research question
- The effect of three different nutrient solutions affects the height and length of basil plants?
- How the effect of three different nutrient solutions affects the change of pH?
- Economic efficiency of basil plants grown in hydroponics?
Research place
I have spent 5 months studied in the green house at Thai Nguyen University of Agriculture and Forestry
I was guided by Prof Nguyen The Hung Currently, he is the vice president of the TUAF, at where he once studied
We discussed the work that I was going to execute in the green house
Particularly, they included: monitoring and observing the growth of basils, with
3 different nutrient solution formulas for hydroponicsin green house Afterward, we a meetingweekly to work on issued questions and solve problems.
Description of your activities
- Monitoring pH on a regular basis
- Monitoring the height of the plant (cm), root length (cm) 5 days at a time
- Monitoring the havested productity of basil under 3 different formula
Timeline
The project is conducted within 5 months from January 1, 2019 to May 31, 2019
LITERATURE REVIEW
General introduction of the hydroponic technique
Hydroponics is a method of soil-free farming where plants are cultivated in nutrient-rich water solutions This technique allows for the roots of the plants to be fully or partially immersed in the nutrient solution, promoting optimal growth and health.
Based on the characteristics of using nutrient solution, it can be divided into two hydroponic systems [7], as follows:
A stationary hydroponic system involves keeping one or all of a plant's roots submerged in a nutrient solution without any movement This method is cost-effective as it eliminates the need for equipment to circulate the liquid However, a significant drawback of this system is the lack of oxygen in the nutrient solution, which can lead to increased acidity and potentially harm the plants.
A mobile hydroponic system utilizes nutrient solutions that are actively circulated during the planting process, ensuring that plants receive adequate oxygen and nutrients Although this system comes at a higher cost, it operates on tidal principles, incorporating aeration and drip irrigation techniques Mobile hydroponic systems can be categorized into two distinct types, each designed to optimize plant growth and health.
- Open hydroponics is a dynamic hydroponic system in which nutrient solutions have no recirculation, leading to the waste of nutrients
- Closed hydroponics is a circulating hydroponic system in which the nutrient solution has recirculation thanks to a nutrient pump system from the reservoir.
Prospects of application of hydroponic techniques in vegetable production
For Vietnam, the application of hydroponic techniques in vegetable cultivation has great practical significances because:
Vietnam's landscape is predominantly hilly and mountainous, with limited land available for agriculture, particularly vegetable cultivation This area is shrinking further due to industrial development, rapid urbanization, and environmental pollution stemming from chemical agricultural practices and human activities.
Vietnam has a rich agricultural heritage, with its people possessing extensive experience in vegetable cultivation Their diligence, strong work ethic, eagerness to learn, and creativity enable them to rapidly adopt and implement new technologies in agriculture.
On January 29, 2010, the Vietnamese government launched a scheme aimed at advancing high-tech agriculture, set to remain in effect until 2020 This initiative outlines a clear roadmap for the development of high-tech applications and enterprises in the agricultural sector, with a specific focus on implementing hydroponic techniques for green vegetable production.
As the economy continues to develop, people's lives are improving, leading to a growing demand for safe vegetable products that enhance quality of life.
Long-term agricultural practices have heavily relied on chemical fertilizers and pesticides, leading to significant pollution of soil, water, and air This pollution has resulted in a drastic decline in beneficial insect populations and an increase in diseases, ultimately contaminating vegetables and threatening both the environment and human health To counter these issues, adopting hydroponic techniques for safe vegetable production is essential, as it adheres to protection standards and enhances the ecological environment This approach not only ensures the safety of agricultural products but also contributes to sustainable agricultural development.
Implementing hydroponic techniques in vegetable cultivation enhances the quality and market competitiveness of green vegetables This approach not only transforms agricultural production structures but also generates employment opportunities, boosts farmers' incomes, and increases foreign currency earnings for the nation.
Research situation and application of hydro technical techniques
2.3.1 Technical situation and application of hydroponics in the world
2.3.1.1 Research results on nutrient solutions for planting plants by hydroponic techniques in the world
Nutrient solutions are essential for hydroponic plant growth, with 16 chemical elements identified as crucial for optimal development, including C, H, O, N, P, K, Ca, Mg, S, Fe, Cu, Mn, Zn, Mo, B, and Cl The first nutrient solution, developed by plant physiologist Knop in the mid-19th century, contained only six inorganic salts, lacking microelements, which limited plant growth This led to the creation of more effective nutrient solutions, such as the Hoagland-Arnon solution, which uses four inorganic salts, and more complex formulations like Arnon's, Olsen's, and Sinsadze's solutions Recent popular options include solutions from FAO and Taiwan, reflecting advancements in hydroponic nutrient formulations.
The significance of nutrient solutions for crops was highlighted by Liebig, Karl Sprengel, Wiegman, and Polsof in 1942, with Sarchs later affirming this through his research on hydroponic techniques, emphasizing the crucial role of roots in nutrient absorption Midmore also stressed the necessity of tailoring nutrient solutions to seasonal crop needs, as various vegetables demand distinct water and nutritional regimes Additionally, Midmore addressed the impact of temperature, noting that optimal conditions enhance enzyme functionality, while excessive temperatures can inhibit enzyme activity.
Researchers have investigated tailored nutrient solutions for various plant species, including Axan's rice, Belouxov sugar beet, Kitxon's tomatoes, Khaan and Xcurea tea, Mori's apples, and Winsor's 1973 tomato-growing solution.
Larsen developed a nutrient solution by enhancing Stainer's solution, which, despite its lower nutrient content, is effective for greenhouse tomatoes and serves as a foundation for subsequent formulations Sudradfat and Herenati (1992) investigated an aqueous mixture from anaerobic fermentation as a hydroponic nutrient solution, revealing that Japanese cucumbers grown with this diluted water exhibited reduced plant height, fruit length, and weight compared to those grown with standard hydroponic nutrient solutions.
According to Carbonell and his partners (1994), the presence of arsenic in nutrient solutions enhances iron (Fe) absorption while inhibiting the uptake of boron (Bo), copper (Cu), manganese (Mn), and zinc (Zn) In hydroponic systems, pH indicates the concentration of hydrogen ions, determining whether the solution is acidic or alkaline Each plant species has a specific pH threshold for optimal growth, typically ranging from 6.0 to 7.5 If the pH drops too low (4.5) or rises above 9, it can harm root health; high pH levels can lead to the precipitation of essential nutrients like Fe²⁺, Mn²⁺, PO₄³⁻, Ca²⁺, and Mg²⁺ A deficiency in any of these elements can manifest as symptoms of nutrient deficiency, potentially leading to plant death.
The electrical conductivity (EC) of a solution significantly impacts salad productivity, particularly lettuce Freigin (1991) identified a critical EC threshold of 5 dS/m for lettuce growth at KNO3 concentrations of 5 and 10 mM, noting that yields decrease by 6.5% for each unit increase in EC above this threshold Additionally, Huet (1994) found that the optimal yield for lettuce occurs at an EC level of 1.6 dS/m.
Research indicates that increasing salt concentration negatively impacts tomato yield Willumsen (1996) found that higher salt levels led to decreased tomato production, while Lopez (1996) noted that adding 50 mM NaCl to nutrient solutions reduced root size, fresh weight, leaf count, and overall yield, along with lower calcium and potassium levels in the plants Conversely, Bartal and Presman (1996) reported an increase in calcium and potassium yield in the solution, although they observed that the dry matter content in tomato fruits increased and the incidence of flower stem rot decreased.
The growth and development of hydroponic plants are significantly influenced by the types and ratios of protein used Sandoval et al (1994) found that substituting ammonium protein for nitrate leads to a decrease in dry matter and wheat grain productivity Elia et al (1997) determined that an optimal NH4+/NO3 ratio of 3/7 is necessary for successful eggplant cultivation Additionally, Gimener et al (1997) reported that the positive effects of ammonium protein on melon growth increased with NH4/NO3 ratios rising from 0 to 1/3.
According to He (1999), in the winter season, the increase of NO3 in nutrient solution does not increase the uptake of NO3 of plants[12]
Plants have varying nutritional needs, particularly for essential nutrients like Nitrogen (N), Phosphorus (P2O5), and Potassium (K2O) According to Wlises Ourny (1982), the nitrogen content in fruits and vegetables is generally lower than that found in leafy vegetables, with a concentration of 140 ppm in leafy varieties Notably, fruit-bearing vegetables exhibit a distinct concentration of these nutrients.
Research indicates that plants experiencing iron deficiency develop white leaves after 3-4 leaves, with chlorophyll particles located outside the protoplasm However, the addition of dissolved iron salts can restore green leaves Furthermore, Asao (1998) found that incorporating activated carbon into nutrient solutions significantly enhances the dry matter content and yield of tomatoes and cucumbers Additionally, Ho and colleagues demonstrated that hydroponically grown tomatoes yield significantly more and exhibit improved quality compared to traditional farming methods.
In 1994, Sandoval and partners in Mexico investigated the effects of substituting a portion of nitrate protein with amol protein in carbonate form for wheat cultivation, finding that this replacement led to a decrease in both dry matter and grain yield Similarly, Carbonell and partners in the USA studied the impact of arsenic on microelement content in hydroponically grown tomato plants, concluding that arsenic in the nutrient solution enhances iron absorption while reducing the uptake of boron, copper, manganese, and zinc, ultimately causing structural damage to the plants.
Recent studies on nutrient solutions in hydroponic techniques have explored various aspects of plant growth and nutrition Maruo and colleagues focused on methods to regulate the water absorption rate in vegetables cultivated on stone and membrane systems Hohjo and his team examined how different nitrogen forms, nutrient concentrations, and calcium levels affect the growth, yield, and quality of tomatoes grown using thin nutrient films Additionally, Pardossi and colleagues investigated the management of mineral nutrition in melons cultivated with thin nutrient films, while Ha and Chung analyzed nitrogen composition in cucumbers grown under varying ionic concentrations.
2.3.1.2 The situation of developing hydroponic techniques in the world
Research from the Agricultural Information and Food Industry Center highlights the growing trend of landless cultivation techniques for leafy and fruit vegetables worldwide Since the introduction of Gericke's deep-water hydroponic system in 1930, numerous commercial plantations have emerged, including the American Hydroponic planting facility in Japan, which utilized reversible nutrient solutions for cultivating green vegetables.
Since 1940, the global area of hydroponics has seen significant growth, expanding from just 10 hectares to approximately 300 hectares by 1970 By 1980, this area surged to 6,000 hectares By 2001, hydroponic cultivation had further increased to between 20,000 and 25,000 hectares, with a production value estimated between 6 and 8 billion USD, highlighting the rapid advancement and economic impact of hydroponic farming.
In 1989, the HydroHarvest facility in Ashby, Massachusetts, was pioneering year-round vegetable production on 3,400 m², with 69% dedicated to lettuce, 13% to watercress, and the remainder to cut flowers and experimental crops By 1994, the U.S had approximately 220 hectares of greenhouse-grown vegetables, with 75% cultivated in soilless systems, primarily featuring tomatoes, cucumbers, lettuce, and chili peppers Notably, by 1991, Northern Europe alone had over 4,000 hectares of vegetables grown in nutrient solutions.
Introducing basil plants
Basil, scientifically known as Ocimum basilicum L, is a fragrant herbaceous plant that typically grows to a height of 50-60 cm This aromatic spice features single, green leaves with slightly tapered edges and produces small white or light purple flowers in clusters Its fruit contains shiny black seeds, which, when soaked in water, are surrounded by a white mucilaginous substance.
Basil leaves are aromatic and spicy, known for their ability to enhance absorption, promote sweating, and act as a diuretic They also provide pain relief and are commonly used as a culinary spice The flowers of the basil plant possess diuretic and neurological benefits, while the fruit offers a sweet and spicy flavor, contributing to improved eyesight.
In addition, basil leaves and branches are used to treat: runny nose, headache, stomach pain, bloating, poor digestion, enteritis, diarrhea, irregular menstruation
Basil's unique aroma elevates the flavor of various dishes, making it a perfect accompaniment to water-based meals like pho, noodles, rice vermicelli, and rolls such as banh xeo and salad rolls.
2.4.2 Hydroponic studies on basil plants
The productivity and qualities of Hydroponically Grown Sweet Basil Cultivars were conducted by Raimondi, G., Orsini, F., Maggio, A., De Pascale, S., & Barbieri,
A study conducted by G (2006) aimed to provide a comprehensive understanding of two cultivars of hydroponically grown sweet basil, specifically Napoletano and Genovese The research investigated the effects of plant density, nutrient solution strength, and light intensity on basil growth The plants were cultivated in a floating system with two different plant densities (100 and 66 plants per square meter) and subjected to two shading treatments: a control group with 0% shading and a 50% shading treatment using a 50% cut-off screen Additionally, two nutrient solutions were tested: single strength Hoagland and double strength Hoagland.
Their morphological characteristics and nutritional value were analyzed from plants and yield components were quantified
A study conducted at Georgia Southern University from August to November 2015 compared aquaponic and hydroponic systems using crayfish (Procambarus spp.) to evaluate the growth, yield, quality, and nutrition of basil (Ocimum basilicum L.) cultivar Aroma 2 Non-circulating floating raft systems were utilized in 95 L polyethylene tanks, with both systems receiving equal amounts of start-up fertilizer The research aimed to understand how crayfish contribute additional nutrients to basil crops Results indicated that aquaponic basil (AqB) outperformed hydroponic basil (HyB) with 14%, 56%, and 65% greater height, fresh weight, and dry weight, respectively, likely due to nutrients from crayfish waste However, chlorophyll content and leaf nutrient levels did not differ between the two systems Further investigation is necessary to explore aquaponic crayfish yield, nutritional dynamics, cost-benefit ratios, and other plant characteristics in soilless systems.
METHODOLOGY
Research subjects
Three different types of nutrient solutions and basil
Experimental materials
The circulating hydroponic system features 90 mm diameter plastic pipes, each 4 meters long, supported by a 60 cm high iron rack These pipes are pre-cut with 5 cm holes spaced 17 cm apart for plant insertion and are arranged with a 10-12 cm gap, sloping at a 10-degree angle towards a receiver tank Nutrient solutions are delivered from a plastic tank, positioned 0.7 meters above the pipes, with adjustable volume and flow rates This setup allows for continuous circulation of the nutrient solution through the tubes, promoting plant growth Seedlings are initially incubated in grain delivery trays and transferred to the hydroponic system once they develop 2-3 true leaves.
- Substrate: it’s mixed according to the ratio of 30% coconut, 40% of soil, 30% of animal manure that has been treated
The plastic basket is crafted from standard plastic material and features a cup shape with a height of 5 cm and a flared mouth measuring 5.5 cm in diameter Designed with perforations at the bottom, this basket allows for efficient water drainage, making it a practical choice for various uses.
Using two types of solution is (TUAF Solution) and (Gia Vien hydroponic solution company)
Group A: KNO3, Ca(NO3)2, MnCl₂
Group B: KH2PO4, KNO3, H3BO3, ZnSO₄, CuSO4, Fe (EDTA)
* Gia Vien hydroponic solution company: No 2
Group A: NH4 NO3, Ca, K2O, Fe (EDTA)
Group B: P4O10, K2O, NH4 NO3, S, Mg, Mn, Bo, Zn, Cu, Mo
* Formula 2: 30% No 1 + 70% No 2, prepared by the research group at (TUAF)
* Formula 3: 30% No 2 + 70% No 1, prepared by the research group of agricultural and forestry university students.
Research scope
The thesis studies on three different nutrion solutions to produce suitable nutrients as well as to bring the highest efficiency for basil plants.
Research Methods
* Method of follow-up sampling:
- Experiment is arranged randomly with 3 times repeating for 13 monitored trees of of each formula
- The 3 nutrient formulas include the 1st nutrient solution (CT1), the 2nd nutrient solution (CT2), and the 3rd nutrient solution (CT3)
- The Formula 1 is the sample used to compare with the other 2
+ From sowing to rooted (days): Count from sowing until there have root
+ From growing to the day when it is put on the hydroponic systems (day): Calculate from the time of germination to the introduction of the hydroponic system
+ Harvesting time (days): Calculate between the first and second harvest, until the eighth harvest
To accurately measure plant height, use a plastic ruler to record the height in centimeters every five days, starting from the base near the substrate surface to the tip of the highest leaf The average height of the monitored trees will be calculated based on these measurements.
To measure root length effectively, use a plastic ruler to assess the growth of roots over a five-day period Measure from the base of the tree, near the substrate, to the tip of the longest root The final root length is determined by calculating the average of the measurements taken from the monitored trees.
- pH: measure everydays, using Ph measuring instrument
Total expenditure (thousand VND): Calculate all actual expenses for vegetable production such as: greenhouse, hydroponic system, slecticity, water and nutrient solution
Selling price (thousand VND / kg): The selling price is based on the price of safe vegetables at the time of harvest
Total sales (thousand VND) = The number of basil plants x sale price
The income (VND thousand) = Total sales - Total expenditure
The data is statistically processed by Excel
DISCUSSION AND LESSON LEARNDED
The time of each growth stage of basil
Table 4.1: The time of each growth stage of basil in three different nutritional formulas
Time counted from previous harvest to: … (days)
Harvesting time first second third fourth fifth sixth seventh eighth
After five days of sowing, seedlings began to develop roots, and within the following 15 days, the plants were transferred to hydroponic systems Once placed in baskets, the vegetables were harvested at intervals of 10, 15, and 20 days, revealing varying growth rates among three nutritional formulas The first formula (ct1) resulted in a harvesting period of 15 to 20 days, averaging five days longer than the second (ct2) and third (ct3) formulas The experiment yielded a total of eight harvests, with ct3 producing four harvests after 10 days, while ct2 yielded two harvests in the same timeframe.
The effect of nutrient solution on the yield of basil
Table 4.2: The average height of basil plants before each harvest in three different nutritional formulas
The average height of basil (cm)
Harvesting first second third fourth fifth sixth seventh eighth
Figure 4.1: The average height of basil plants before each harvest in three different nutritional formulas
A v e ra g e h e ig h ts o f h a rv e st e d p la n ts ( cm )
Average heights of harvested plants (cm)
The analysis of tree growth from the first to the eighth harvest reveals significant differences among the three treatments Initially, when branches reached 10 to 15 cm, harvesting commenced Although treatment ct1 recorded the lowest height among the three formulas, it initially produced higher figures than the others Subsequent harvests showed that ct1's plants were consistently shorter than those in ct2 and ct3, with height differences ranging from 2 cm to 8 cm Notably, ct3 exhibited optimal growth, achieving an average height of 40 cm over eight harvests, compared to ct2's 39 cm and ct1's 34 cm According to the encyclopedia, basil trees typically reach about 30 cm in height After six months of experimentation, the basil plants attained a maximum height of 40 cm, resulting in thicker trunks and darker, sturdier leaves compared to their earlier growth stage of 20 cm to 25 cm.
Table 4.3: The average root length of basil plants before each harvest in three different nutritional formulas
The average root of basil (cm)
Harvesting first second third fourth fifth sixth seventh eighth
Figure 4.3: The average root length of basil plants before each harvest in three different nutritional formulas
R o o t le n g th s o f h a rv e st e d p la n ts ( cm )
Root lengths of harvested plants (cm)
The study highlights the significant difference in root length between the first and eighth harvests, indicating that longer roots enhance nutrient absorption in plants Specifically, the roots of the trees in CT3 were found to be longer than those in the other two formulas Over a six-month period, root lengths increased from 15 to 20 cm, varying by tree type In contrast, the average root length in CT1 showed a modest increase from 1 cm to 3 cm, which was notably lower than the increases observed in the other two formulas, where root lengths expanded from 1 cm to 6 cm with each harvest.
Table 4.4: The mass of basil plants in three different nutrient formulas over eight harvests
The amount of harvested each times (gam)
Harvesting first second third fourth fiveth sixth seventh eighth
In a study examining the growth of basil plants over eight harvests, Figure 4.5 illustrates the mass of the plants across three different nutrient formulas Additionally, Tables 4.1, 4.2, and 4.3 present the plant height and root length for treatments ct1, ct2, and ct3, arranged from lowest to highest The findings indicate that the branching and sprouting capabilities of the basil plants align with this hierarchical order.
W e ig h ts o f h a rv e st e d p la n ts ( g ra m )
Weights of harvested plants (gram)
The data presented in Table 4.4 demonstrates that CT3 consistently achieved the highest yield at each harvest, ranging from 750g to 1300g, surpassing both CT1 and CT2 Notably, CT3 exceeded 1000g on four occasions out of eight, while CT1 and CT2 did not reach this benchmark at all In the final harvest, CT1 recorded a weight of 860g and CT2 weighed 950g.
Different nutrients have different effects on the ability to change pH
Each crop requires a specific pH range for optimal growth When the pH level of the soil or solution falls outside this ideal range, it can hinder the plant's ability to absorb essential nutrients, ultimately impacting its overall health and development.
Figure 4.6: The essential nutrients for plants and the pH level at which plants can absorb these nutrients
Plants in highly acidic environments often suffer from various symptoms, including toxicity from aluminum (Al), hydrogen (H), and manganese (Mn) Additionally, these conditions can result in deficiencies of essential nutrients like calcium (Ca) and magnesium (Mg).
In contrast, in an alkaline environment, the solution will have molybdenum (Mo) phenomenon Meanwhile, phosphorus (P), iron (Fe), manganese (Mn), zinc
(Zn), copper (Cu) and cobalt (Co) are reduced, and may adversely affect the development of Crops [15]
The pH of a solution is influenced by the substrate, which may require treatment to ensure chemical inertness Over time, as the substrate is used, organic elements accumulate, necessitating more frequent adjustments to maintain the desired pH range.
Several factors can influence pH changes in experiments To decrease alkalinity when the pH is 7 or higher, edible vinegar can be utilized Conversely, if the pH drops to 4 or lower, a KOH solution is effective for reducing acidity.
Researchers found that basil plants thrive at a pH level between 5.2 and 6.1, which promotes healthy root growth and optimal nutrient absorption Maintaining this pH range enhances plant height and overall yield Conversely, if the pH exceeds 6.5, basil plants may experience yellowing leaves due to their inability to absorb essential micronutrients.
Figure 4.7 illustrates the frequency of pH fluctuations, revealing that CT2 and CT3, with pH levels between 5-6 and 6-7, are ideal for optimal growth In contrast, CT1 exhibits higher pH levels around 4-5 and 7-8, contributing to reduced crop yields when compared to the two nutrient formulations.
CONCLUSION
Basil, a versatile herb, can be successfully grown in hydroponic systems, but it requires specific nutrient solution criteria for optimal cultivation The ideal pH level for basil growth should be maintained between 5.0 and 6.9, while the total dissolved solids must be adjusted to fall within the range of 700 ppm to 1100 ppm.
In an experiment utilizing the third nutrient formula (CT3), basil plants exhibited superior growth, achieving an average height of 40 cm, compared to 39 cm for CT2 and 34 cm for CT1 Additionally, the root weight of plants grown with CT3 was significantly higher, underscoring the effectiveness of this nutrient solution for optimal basil cultivation.
1000 gram while the numbers of the other 2 formulas didn’t exceed 1000 gram
Cultivating basil using hydroponic systems offers significant profitability with minimal investment, costing under 500,000 VND for every 10m² over five months During this period, each harvest can yield total income of up to 791,000 VND, resulting in a profit of 331,000 VND The harvested basil is fresh and hygienic, making hydroponic cultivation a viable option not only in Vietnam but also in other countries Additionally, research indicates that the CT3 variety produces longer roots, averaging about 17 cm, which enhances the plant's ability to absorb nutrients and water, ultimately leading to stronger growth.
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