Biochemical Characterization of Microbials and Their Effects on the Growth and Yield of Multiplier Onion (Allium ascalonicum L.) in Northwestern Philippines
Onion is a highly nutrient-responsive crop. Conventional methods of fertilization have undoubtedly helped in improving both bulb yield and quality. But lately, routine management practices in the Philippines appear to be incapable of maintaining yields over the long term. The steady depletion of native soil fertility and the occurrence of multiple nutrient deficiencies in onion fields have led to the use of microbials in combination with fertilizers for sustainable onion production. Biofertilization methods played an essential role in plant nutritional requirements since biofertilizers were reported to enhance crop productivity through improving plant nutrition, enhancement of nutrient availability, nitrogen fixation, phosphate solubilization, and plant hormone production. Three microbial strains with biofertilizer potentials were chosen to evaluate for growth promotion and yield of multiplier onion (Australian variety). A field experiment was designed in a strip plot design comprising of fertilizer source and microbials. Data obtained were analyzed using analysis of variance, and mean values were subject to Honestly Significant Difference Test at P = 0.05. Two of the three microbials used in this experiment were identified as Bacillus subtilis and Paenibacillus polymyxa through their biochemical characterization. The results of field experiment showed that onion treated with P. polymyxa significantly produced the longer laminar length of onion seedlings at 45 days after treatment (33.24 cm) compared to untreated control (28.44 cm). Also, onion treated with B. subtilis strains 1 (32.02 cm) and 2 (31.31 cm) showed a significant increase in laminar length compared to control. The treated onion seedlings with microbials grown under conventional practice produced larger bulbs. The yield of harvested green onion and dry bulbs was higher in microbial-treated onion plots compared to the untreated (18.16 t ha−1 versus 10.99 t ha−1). The higher percentage of marketable yield (97.07%) of green onion has resulted in microbial-treated plots. Our results suggest that treatments supplying inorganic fertilizers and microbials or organic fertilizer and microbials in combination generated a significant bulb yield response over the control.
KeywordsAllium ascalonicum L. Growth promotion Inorganic fertilizers Organic fertilizer and Bacillus subtilis Paenibacillus polymyxa fertilizers
Special thanks are given to the Philippine Council for Agriculture, Aquatic, and Natural Resources Research and Development for funding this research and the Mariano Marcos State University administration for their full support.
- BAS (2013) Production of Multiplier Onion in the Philippines.Google Scholar
- Berks BC, Ferguson SJ, Moir JWB, Richardson DJ (1995) Enzymes and associated electron transport systems that catalyze the respiratory reduction of nitrogen oxides and oxyanions. Biochim Biophys Acta (BBA) – Bioenergetics 1232(3):97–173Google Scholar
- Bucao DS, de Leon DRS (2014) Isolation, characterization, and evaluation of plant growth-promoting rhizobacteria from rhizospheres of sugarcane (Sacharum officinarum) and wild lily sp. Sci Technol J 4(1):1–11Google Scholar
- Coelho MRR, Von der Weid I, Zahner V, Seldin L (2003) Character of nitrogen-fixing Paenibacillus species by polymerase chain reaction-restriction fragment length polymorphism analysis o part of genes encoding 16S rRNA and 23S rRNA and by multilocus enzyme electrophoresis. FEMS Microbiol Lett 222:243–250CrossRefGoogle Scholar
- Corpuz AS (2013) Response of shallot onion, Australian variety (Allium ascolanicum L.) to sources of fertilizer materials. Unpublished undergraduate thesis. Mariano Marcos State University, City of Batac, Ilocos NorteGoogle Scholar
- Haque NA, Dave SR (2005) Ecology of phosphate solubilizers in semiarid agricultural soils. Indian J Microbiol 45:27–32Google Scholar
- Kim YC, Leveau J, McSpadden Gardener BB, Pierson EA, Pierson LS III, Ryu CM (2011) The multifactorial basis for plant health promotion by plant-associated bacteria. Appl Environ Microbiol 77:1548–1555Google Scholar
- Kloepper JW, Schroth MN (1978) Proceedings of the 4th international conference on plant pathogenic bacteria, vol 2, Gilbert-Clarey, Tours. pp 879–882Google Scholar
- Lazarovits G, Nowak J (1997) Rhizobacteria for improvement of plant growth and establishment. Hortic Sci 32:188–192Google Scholar
- Sivasakthi S, Kanchana D, Usharani G, Saranraj P (2013) Production of plant growth promoting substance by Pseudomonas fluorescens and Bacillus subtilis isolates from paddy rhizosphere soil of Cuddalore district Tamil Nadu, India. Int J Microbiol Res 4:227–233Google Scholar
- Schroth MN, Hancock JG (1982) Disease suppressive soil and root colonizing Bacteria. Soil Sci 216:1376–1381Google Scholar