Assessment of multifunctional biofertilizers on tomato plants cultivated under a fertigation system Phua, C.K.H., Abdul Wahid, A.N. and Abdul Rahim, K. Malaysian Nuclear Agency (Nuclear Malaysia) Ministry of Science, Technology and Innovation, Malaysia (MOSTI) E-mail: [email protected]
ABSTRACT Malaysian Nuclear Agency (Nuclear Malaysia) has developed a series of multifunctional bioorganic fertilizers, namely, MULTIFUNCTIONAL BIOFERT PG & PA and MF- BIOPELLET, in an effort to reduce dependency on chemical fertilizer for crop production. These products contain indigenous microorganisms that have desired characteristics, which include plant growth promoting, phosphate solubilising, antagonistic towards bacterial wilt disease and enhancing N2-fixing activity. These products were formulated as liquid inoculants, and introduced into a fertigation system in an effort to reduce usage of chemical fertilizers. A greenhouse trial was conducted to evaluate the effectiveness of multifunctional biofertilizers on tomato plants grown under a fertigation system. Multifunctional biofertilizer products were applied singly and in combination with different rates of NPK in the fertigation system. Fresh and dry weights of tomato plants were determined. Application of multifunctional biofertilizer combined with 20 g NPK resulted in significantly higher fresh and dry weights as compared to other treatments.
ABSTRAK Agensi Nuklear Malaysia (Nuklear Malaysia) telah membangunkan satu siri baja bioorganic pelbagai fungsi, iaitu MULTIFUNCTIONAL BIOFERT PG & PA and MF-BIOPELLET, dalam usaha mengurangkan pergantungan terhadap baja kimia dalam penghasilan tanaman. Produk ini mengandungi mikroorganisma setempat yang menpunyai ciri yang dikehendaki seperti penggalak pertumbuhan, pengurai fosfat, antagonis terhadap penyakit layu bakteria dan menggalak aktiviti pengikat N2. Produk ini difomulasi dalam bentuk cecair dan diperkenalkan ke dalam sistem fertigasi untuk mengurangkan penggunaan baja kimia. Satu kajian rumah kaca telah dilakukan keatas pokok tomato dengan mengguna sistem fertigasi. Produk biobaja pelbagai fungsi diberi secara tunggal dan gabungan dengan pelbagai kadar NPK dalam sistem fertigasi. Berat basah dan kering pokok tomato diukur. Aplikasi biobaja pelbagai fungsi dengan gabungan 20 g NPK memberi hasil berat basah dan kering yang bererti berbanding dengan rawatan lain.
INTRODUCTION Fertigation has been described as the application of plant nutrients in irrigation water to accomplish fertilization. It is becoming widely accepted in the industry due to the fact that a properly designed system will perform accurately; it is economical, easy to install, saves time, labour and most importantly, will save money (Selim et al., 2010). Biofertigation is the use of bioinoculants or biofertilizer microorganisms in a fertigation system. Biofertigation can precisely deliver the bioinculants in the root zone (Gomathy et al., 2008). Efficiency studies of biofertigation in terms of nutrient uptake have been conducted on cotton (Gomathy et al., 2008) and broccoli (Selim et al, 2009). They reported that biofertigation increased growth of these plants. Malaysian Nuclear Agency (Nuclear Malaysia) has developed a series of multifunctional bioorganic fertilizers namely, MULTIFUNCTIONAL BIOFERT PG & PA and MF-BIOPELLET, in reducing dependency on chemical fertilizer for crop production (Phua et al., 2009a; 2009b). These products use 100% natural products, with no added chemicals. They are, thus, ‘Green Products’ - environmental friendly, optimising the bioresources, pathogen-free, and are suitable for vegetables. These products contain indigenous microorganisms that have desired characteristics, including plant growth promoting, phosphate solubilising, antagonistic towards bacterial wilt disease and enhance N-fixing activity. The objective of this study was to adapt multifunctional biofertilizer for use in a biofertigation system.
MATERIALS AND METHODS Biofertigation experiment of tomato was carried out at greenhouse using an existing fertigation system. Two-week-old tomato seedlings were transplanted into pots that contained 1 kg of soil mixture consisting of soil, peat and sand in the ratio of 2:1:1. All seedlings received biofertilizers. Biofertilizers were prepared by culturing three selected isolates used in MULTIFUNCTIONAL BIOFERT PG & PA and MF-BIOPELLET on nnutrient broth for 48 h ((Phua et al., 2009a; 2009b). A volume of 500 mL of the cultures (approximately 1012 cfu/ml) was diluted in 500 L of water and given as biofertigation. Biofertilizer application through drip was done twice in a day. Four treatments were used in this experiment. Treatment 1 (T1) comprised biofertilizer only. Treatment 2 (T2), 3 (T3) and 4 (T4) were biofertilizer with added 20, 2 and 0.2 g of NPK, respectively. There were three replications for each treatment with five plants for each replication. The experimental design was a completely randomised design (CRD). Crops were harvested after two months. Fresh and dry weights were determined. Data were analysed by ANOVA with the means separated by Duncan’s test (P <_0.05).
RESULTS AND DISCUSSION Combinations of microbial inoculate and chemical fertilizers given through drip irrigation have shown variable results. Biofertigation with 20 g NPK and biofertilizer (T2) significantly recorded the highest fresh weights of 101 g (Figure 1) as compared to other treatments. Figure 2 shows both biofertilizer treatment 2 (T2) and 3 (T3) with 20 and 2 g NPK, respectively, also significantly recorded the highest dry weights of the seedlings as compared to other treatments. Dry weight of treatment 2 was 13 g and treatment 3 was 12 g. There was no significant difference for treatments 2 and 3 (Figure 2). This indicated application of 2 g of NPK with biofertilizer was sufficient for plant growth. Combination of biofertilizer with NPK increased the growth of tomato seedlings, which may due to the frequency of biofertigation that was applied twice a day. Therefore, soil moisture may increase, leading to effective absorption of nutrients and increased phosphate solubilising activity and production of plant growth hormone by the inoculants. Efficiency studies of biofertigation in terms of nutrient uptake have been conducted on cotton (Gomathy et al., 2008) and broccoli (Selim et al, 2009). They also reported that biofertigation increased growth of these plants. Although the present experiment showed biofertigation could increase the growth of tomato seedlings, further investigations of biofertigation, including on shelf life of biofertilizer and their application on soilless mixture should be conducted. Figure 1: Fresh weights (g) of tomato seedlings.
Figure 2: Dry weights (g) of tomato seedlings.
CONCLUSIONS Combination of 2 g of NPK with biofertilizer using biofertigation system enhanced the growth of tomato seedlings in a greenhouse trial. Further investigation of biofertigation should be investigated. ACKNOWLEDGEMENT The authors wish to express their gratitude to Nuclear Malaysia and Ministry of Science, Technology and Innovation, Malaysia (MOSTI) for the technical and financial support (02-03- 01-SF0051). The able technical assistance of Abdul Razak Ruslan, Latiffah Norddin, Hazlina Abdullah and Maizatul Akmam Mhd Nasir, is greatly appreciated.
REFERENCES Gomathy, M., Sathya Prakash, D., Thangaraju.,M., Sundaram., S.P. and Manicka Sundaram, P. (2008). Impact of biofertigation of azophosmet on cotton yield under drip irrigation. Research Journal of Agriculture and Biological Sciences 4(6):695- 699
Phua, C.K.H., Abdul Rahim, K. and Abdul Wahid, A.N. (2009a). Evaluation on multifunctional biofertilizer formulation on selected vegetable crops using the N-15 isotopic tracer technique. In: 31th Symposium of the Malaysian Society for Microbiology”, Penang.
Phua, C.K.H., Abdul Wahid, A.N. and Abdul Rahim, K. (2009b). Development of indigenous microorganisms for multifunctional biofertilizer formulation and evaluation on their effectiveness on Chinese ccabbage using isotopic tracer technique. In: Simposium Biologi Malaysia 2009, Bangi, Selangor. Selim, E.M., Abd El-fattah., A.A., Abouel-Magd., M.M and Khalafallah., M.A. (2009). Efficiency of bio-fertigation on nutrients uptake by broccoli and soil microbial biomass under sandy soil conditions. Eurasian Journal of Agricultural & Environmental Sciences 6(3):280-286.
Selim, E.M., El-Neklawy, A.S. and Mosa, A.A. (2010). Humid acid fertigation of drip irrigated cowpea under sandy soil conditions. Eurasian Journal of Agricultural & Environmental Sciences 8(5):538-54.3