Observation of Aqua-Bio fertilizer nutrients influence of Trigonella foenum- graecum L. growth in mediated Aquaponics system for food security

Received: 21/Mar/2019, Accepted: 10/Apr/2019, Online: 30/Apr/2019 AbstractThe conception of Aquaponics is a synergistic combination of aquaculture and hydroponics that nurture plants with aquaculture water. It is the internationally improved agricultural practices, are needed to assuage rural poverty and enhance food security. Aquaponics is a soil-less combined approach to proficient and sustainable intensification of agriculture that meets the needs of water scarcity inventiveness and generated modern farming practices in agriculture. The nutrient-rich fish water from the fish tanks is used to fertigate hydroponic production beds. To improve the production efficiency can be used bio fertilizers (Aquaponic water and Gracilaria corticata extract) as a liquid it contains organic macro, micronutrient and growth hormones. Tilapia fish produced the nutrient that is utilized by the plant Trigonella foenumgraecum L. The Physico-chemical parameter of both bio fertilizers should be assessed by using the standard procedures. The fish effluent water is compared with the Gracilaria corticata red seaweed extract by foliar spray and combining with both liquid bio fertilizers (Aquaponic water and seaweed extracts). Morphological growths of the plants were assessed. The combination of Aquaponic water and Gracilaria corticata seaweed extract was given the good result, but the estimation (15.26± 0.29, 24.06± 0.27, 30± 0.64, 35.94 ±0.28 cm plant height at 7, 14, 21 and 28 DAS) (2.6± 0.1 branches at 30, DAS) (533.67 ±11and 51 ± 1 mg shoot and root fresh weight per plant) leaf area (46.62±0.89cm2) at 28 DAS was related to the Aquaponic water in the plant Trigonella foenumgraecum L. Thus, the present result revealed that the integrated aquaponic system is the new agricultural farming systems with liquid bio fertilizers are ecofriendly practice for food security.


I. INTRODUCTION
Aquaponics is an integrated method that combines recirculating aquaculture and hydroponics [34], in which the water from the fish tanks that is enriched in nutrients is used for plant growth. Lehman et al., (1993) deliberated a sustainable agriculture as a process that does not exhaust any non-renewable resources that are fundamental to agriculture in order to endure the farming practices. Francis et al., (2003) append that sustainable agricultural production can be achieved by resembling natural ecosystems and "designing systems that close nutrient cycles", which is the main characteristics of Aquaponics. The absolute product of bacterial conversion is a nitrate, which the main nitrogen source for plant growth in an Aquaponic system [12,15,35]. The lower nutrient concentrations are acceptable for an Aquaponics system because the nutrients are produced daily with the fish metabolic activities as well as mineralization of organic matter [36,16]. Conventional hydroponics necessitate mineral fertilizers in order to supply the plants with necessary nutrients, but the Aquaponics systems use the obtainable fish water that is rich in fish waste as nutrients for plant growth. The synergistic interaction of aquaculture and hydroponics are converted into strengths. This combination significantly minimizes the need for input of nutrients and output of waste, unlike when running as separate systems. Minerals transfer from aquaculture to hydroponics support efficient nutrient recycling and relatively safe food (fish and vegetables) [49]. Media-filled grows bed is the most popular intention of small-scale Aquaponics. This method is strongly recommended for most developing areas. This type has well-organized with space, low cost and are suitable for beginners because of their simplicity [30]. It was filled with coco peat because it has a pH neutral, low-cost, lightweight, highwater retention; support the plant in the medium level, easy to work but short lifespan [18]. The Trigonella foenum-graecum L. (Fenugreek) plants are grown in the media bed. It is the medicinal plant from the Fabaceae family originated in central Asia [1]. Its green leaves containing β-carotene (19 mg/100 g), ascorbate (220 mg/100 g) [48], fiber, iron, calcium and zinc even more than the regular food items [27]. The leaves and seedling of fenugreek are eaten as greens. The leaves have a bitter taste and a unique odour [44]. Moreover, the Tilapia (Oreochromis niloticus) fish has many favorable characteristics like poor water quality, wide salinity ranges, water temperature ranges, low dissolved oxygen levels, and elevated ammonia concentrations adopt in Aquaponic production [31]. Therefore, we have conducted experiments on Tilapia fish in this system.

Gracilaria corticata is used as a liquid fertilizer
Gracilaria corticata Seaweed (marine macroalgae) has been used as fertilizer help to promote plant growth. The extract of this seaweed signs successful seed germination, saplings development, increase plant tolerance to environmental pressures [52,53] and improve plant growth and yield [17,55,20,21,6]. Foliar application of seaweed liquid gives many beneficial effects on the plant growth as they contain growth-promoting hormones (IAA, IBA and Cytokinins) [5,10,19]. Seaweed liquid is available in the market as liquid bio-fertilizer. Therefore, in this present study aimed to prove the Aquaponic water and seaweed liquid is the Aqua-biofertilizer with the growth performance of Trigonella foenum-graecum L. plants in the Oreochromis niloticus (Tilapia) mediated Aquaponic system. Aquaponic System. a denotes Media Filled Aquaponic system; b represents plants grown in the Aquaponic System.

II. MATERIALS AND METHODS
The Aquaponic system was designed according to Bernstein (2014) model. The Aquaponic system was comprised of two fish tanks about 142 litres. The fish tanks were covered with aluminum net, it prevents fish from jumping out and prevent leaves, debris from entering and prevent predators such as cats and birds from attacking the fish. The tap water was located near the rearing tanks, supplied water for a short distance to the fish rearing tank. The conformity of nitrification and nutrient availability in the Aquaponics system was acquired pH= 7. The fish tanks were aerated with 10-watt motor to avoid insufficient oxygen level. The water from the fish tanks were flowed by the gravity and then it was entering the hydroponic grow bed. The pipes were plumped to join media-filled grow bed with the fish tank having inlet and outlet of water. An overflow pipe was set at 10 cm for maintaining a constant water level in the plant bed. The hydroponics media-filled grow bed was filled with Aquaponic water; it was drained and entered into the sump tank. The capacity of the sump tanks were 20 liters. It was the lowest part of the system. The submersible pump was fitted inside the sump tank that was returned the treated culture water to the rearing tank. The procedure was followed in both the tanks. About 20 nos of 2.5cm length and 4-6 gm Tilapia fingerlings

Collection of the seed
The Trigonella foenum-graecum L plant seeds were bought in the Tamil Nadu Agricultural University (TNAU), Coimbatore. The seeds with uniform size, color and weight were chosen for the experimental purpose. A hundred seeds were soaked in the water overnight for germination. The four grow beds were directly sown with seeds. In each media-filled grow bed 25 seeds were sown because it was helped to measure the seed germination days. The procedure was followed in each grow bed.

Collection of seaweed
The seaweed was collected in Ramanathapuram district, Tamil Nadu in the latitude of 9° 17'N and longitude of 80°10'. The extract was prepared from the red seaweed Gracilaria corticata. About 1 kg of fresh and healthy seaweed was collected. The sample was washed thoroughly in seawater followed by tap water to remove the extraneous materials and sand particles.

Preparation of seaweed liquid fertilizer
The freshly collected seaweed was shade dried for ten days that dried material was finely powdered. From the dried powder, 50 grams of powder were extracted with 500 ml of boiling water for 60 min and then filtered. The resulting extract was cooled and taken as a 100 % concentration of the SLF [37]. The seaweed liquid fertilizer was refrigerated between 0°C and 4 °C.

Experimental design and treatments
The effect of Aquaponic fish effluent water and seaweed extracts on the growth of fenugreek was evaluated using various treatments applied as coco peat used media filled grow beds. The treatment dose was 20% seaweed liquid fertilizer. [54,33]. Low concentration is effective for greens. The seaweed liquid fertilizer was given weekly once. T 1 grow bed was a control, T 2 was Aquaponic water, T 3 was seaweed liquid fertilizer (20%) and T 4 was Aquaponic water and 20% seaweed liquid fertilizer.

Physico-chemical properties of Aquaponic water and Gracilaria corticata seaweed
The physico-chemical parameter such as pH (Hanna, HI98107), Calcium, and Magnesium, Sodium, and Potassium (Varian spectra-220AA atomic absorption spectrophotometer) of Aquaponic water and seaweed extract were recorded. The growth parameter of Trigonella foenum-graecum L plant was observed at 7days interval that included average height (by meter rule), seed germination, and the leaf area was calculated (LA=0.5*L*W, Where: LA=Leaf area) [32]. The average number of plant branches was counted and measured in biomass. The results were performed by using Microsoft Excel, 2010.

Macro and micronutrients present in the aquaponic water:
Macro and Micronutrients of the Aquaponic water values were shown in the Tables 2 and 3. The results showed that Ammonium concentration level in the Aquaponic water and Nitrate levels were 0.35±.02 mg/l and 37±1.2 mg/l respectively, nitrate level was higher in Aquaponic water. Phosphate is an important ingredient nutrient. This value of phosphate found in Aquaponic water was marked as 11±1.15 mg/l. The potassium level was recorded as 26±1.15 mg/l. Calcium and Magnesium levels were 30±.6 mg/l and 16.2±.8 mg/l. The micronutrients of the Iron level was recorded as 0.2±.06 mg/l. Zinc and manganese content were at the scale 0.4±.0601mg/l, 0.08±.01mg/l ( Table 2).
Aquaponic water as noted by Licamele (2009) observed higher growth (50 mg/l N-Nitrate) in Lactuca sativa in an aquaponic integrated system. Similarly, the present result indicated that higher plant growth (Trigonella foenum-graecum L) as observed in Aquaponic water was 37 mg/l. Endut et al., (2011) observed that the phosphorus (P) concentration of aquaponic water was within the above limit.The present result also indicated a similar aquaponics system. The minimal concentration of aquaponic water was acceptable to the plants in the form of continuous aquaponic fish effluent. This concentration has been found to be sufficient for the plant growth because the available nutrient was often enriched by the aquaponic water. It helped the root formation along with the growth. Villarroel et al., (2011) reported that the growth of strawberry was higher with potassium concentration at 9-15mg/l, while using aquaponic water (Oreochromis niloticus). The present result also indicated that the concentration at the level 26±1.15 mg/l, has been solely responsible for the higher plant growth with enhanced photosynthetic efficiency. Tomasi (2011) reported that the concentration of Iron, Zinc and manganese could be delivered to the plants, especially the shoot system, leaves has been prevented pathogen attack for a long time and also reported that the ability of these molecules to induce systemic resistance in the tomato cultivation.

Macro and micronutrients present in the Gracilaria corticata seaweed
Nitrate level in the Gracilaria corticata seaweed was 56±0.4 mg/l. Calcium, Magnesium, Potassium and Phosphorus level were 72±0.6, 49±0.7, 10.11±1.8 and 15±0.3 mg/l (Table 2). Iron, Manganese, and Zinc present in the seaweed were 0.44±0.9, 0.32±0.3, 0.75±0.3 mg/l (Table 3). Macro and micronutrients and growth hormones found in the seaweed were supporting the plant growth [13,54,33]. It was reported that the presence of plant growth regulators and nutrients in the low concentration of SLF enhanced the growth of root and shoot [28]. Growth hormones Auxin, Cytokinin and Gibberellin levels in the Gracilaria corticata were 3.1, 9.3 and 5.2mg/l respectively (Table 4). They play a pivotal role in the growth of plants. Auxin increases the production and let water enter into the cells, activating H-ATPase pumps. This procedures lead to the growth of cells and simultaneously helps the growth of plants [46]. The findings reported the presence of auxin in the extracts of Ascophyllum nodosum [39] and Ulva sp., in the extracts of cytokinins [41]. The present study showed that extracts from the Gracilaria corticata has been instrumental in promoting the growth characteristics of fenugreek plants.

Seed germination of Trigonella foenum-graecum l. Plant
The seed germination was observed in the Trigonella foenum-graecum L. (Fig.1) seed, which was used in the different substratum. A hundred seeds were selected for germination. The seeds were soaked in the distilled water overnight, then 25 seeds were being sown in each grows bed. In the Aquaponic water mixed with foliar sprays of Gracilaria seaweed, seeds germinated within 2 days.The similar result was observed and followed by the Gracilaria corticata seaweed used in the media bed, the seeds germinated in 3 days and in control media bed it took 4 days. This result indicated that the aquaponic water used with seaweed extract seeds has a higher growth rate while compared to the Gracilaria seaweed and the control.

Plant height (cm)
The plant height was recorded at 7,14,21, and 28 days after sown (DAS  These findings relate to the findings of Malhotra et al. (2006) reported that the Azospirillum sp. The number of branches was increased by greater nitrogen levels.The probable reason for the increased number of branches due to the improved rates of photosynthesis, supplied essential nutrients for maximum branch growth or change in auxin apical dominance.

Shoot and Root weight per plant (mg.)
The shoot and root weight of the fenugreek plant increased within the different treatments were given in Table 6. The maximum 533.67 ±11and 51 ± 1 mg shoot and root fresh weight per plant was recorded in treatment T4 (Aquaponic fish effluent water+ seaweed liquid fertilizer), followed by T2 (Aquaponic fish effluent water) (481± 5.5, 51±1mg), T3 (seaweed liquid fertilizer) (450. 67±7.09, 46±1mg) and While the lowest shoot and root weight was found inT1 (control) (410.67 ±11, 43.3 ±1.5mg). This may be due to the application of major and minor nutrients, through both liquid bio-fertilizer. Ultimately, improve the plant growth fresh weight and dry weight of the plant. These results were concurred with the findings of Sharma  The data (Table 7) revealed that the difference among treatments with the leaf area at different stages of plant growth. The mean leaf area increased from 1.14±0.13 cm 2 at 7 DAS to 46.62±0.89cm 2 at 28 DAS. The aquaponic water showed a maximum leaf area (46.62±0.89cm 2 ) at 28 DAS, whereas, the control showed the minimum leaf area (24.04±0.61cm 2 ) at 28 DAS. The number of leaves is dependent largely upon the number of nodes and also on the number of branches both primaries and secondaries arising on the main shoot of the plant. The findings were harmony with the results of Nehara et al., (2002).

IV. CONCLUSION
This study concludes that Aquaponic water and seaweed liquid fertilizers are Aqua bio-fertilizers and eco-friendly products which has given different effects on the growth of Trigonella foenum-graecum L cultivation indeed improves the yield and quality of the plant while physical growth is also enhanced. The lower concentration of aquaponic water was acceptable to the plants Trigonella foenum-graecum L because continuous supply of aquaponic water. Hence, this simple practice of application is an eco-friendly and sustainable food production system.This soil-less culture system is modern farming practices in agriculture for food security.