Efficiency of microbial population in rhizosphere at different growth stages of paddy in Vertisol of Chhattisgarh

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1 An Asian Journal of Soil Science Volume 7 Issue 2 December, 2012 Research Article Efficiency of microbial population in rhizosphere at different growth stages of paddy in Vertisol of Chhattisgarh RAKESH KUMAR BHAGAT AND DEVENDRA KUMAR DEWANGAN MEMBERS OF RESEARCH FORUM : Corresponding author : DEVENDRA KUMAR DEWANGAN, Department of Agronomy, Indira Ghi Krishi Vishwa Vidyalaya, RAIPUR (C.G.) INDIA devendewangan@gmail.com Co-authors : RAKESH KUMAR BHAGAT, Department of Soil Science, Indira Ghi Krishi Vishwa Vidyalaya, RAIPUR (C.G.) INDIA Received : ; Revised : ; Accepted : Summary A field study was carried out during Kharif season of at the Research Instructional Farm of Indira Ghi Krishi Vishwavidyalaya ( IGKV), Raipur. Experiment was conducted to examine the efficiency of microbial population in rhizosphere at different growth stages of paddy in Vertisol of Chhattisgarh as influenced by long term application of fertilizers manure. The experiment was carried out in Romized Block Design with 4 replications having treatments: T 1 (Control without fertilizer),, (100% N alone), (100%NPK+FYM) (50%NPK+green manure). A medium duration high yielding paddy variety Mahamaya was taken as crop. The microbial population (bacteria, fungi, actinomycetes, N 2 fixing bacteria) density at different growth stages in paddy crop showed variations in microbial population due to fertilizer application, the highest microbial population was recorded under (100% NPK +FYM) followed by (50%NPK+GM), T 1 (Control) recorded the lowest microbial population. The grain yield of rice was observed to be significantly influenced due to different treatments. The highest was recorded with (100%NPK +FYM) was found significantly superior over rest of the treatments. The lowest grain yield was noticed under control plot. Key words : Microbial analysis, N 2 -fixing bacteria, Bacterial population, Fungal population, Actinomycetes population, How to cite this article : Bhagat, Rakesh Kumar Dewangan, Devendra Kumar (2012). Efficiency of microbial population in rhizosphere at different growth stages of paddy in Vertisol of Chhattisgarh. Asian J. Soil Sci., 7(2):. Introduction Microbial population in the rhizosphere zone of the soil influence plant growth attributing characters because they affect soil chemical properties interact with plant roots, where as the influence observed can be beneficial, neutral, or deleterious (Sakai et al., 2004). Understing, rhizosphere microorganisms is important for their effective use for lowinputs, sustainable agriculture (LISA) phytoremediation (Doi et al., 2006). The microorganisms in the rhizosphere soil are known to compose the complex of the microbial community, which might be changeable depending on plant root exudates (Watt et al., 2006). Beneficial plant-microbes interaction in the rhizosphere soil is primary determinants of plant health soil fertility. Arbuscular mycorrhize are the most important microbial symbiosis for the majority of plants, under conditions of P-limitation, influence plant community development, nutrient uptake, water relations above-ground productivity. They also act as bioprotectants against pathogens toxic stresses. Soil microorganisms are paramount in the biogeochemical cycling of both inorganic organic nutrients in the soil in the maintenance of soil quality. In particular, microbial activity in the rhizosphere soil is a major factor that determines the availability of nutrients to plant has a significant influence on plant health productivity. The soil plant microbe interactions are complex there are many ways the outcomes can influence plant growth health soil productivity. The results reported may be harmful, neutral or beneficial to the plants. Resources Research Methods The present study entitled efficiency of microbial HIND AGRICULTURAL RESEARCH AND TRAINING INSTITUTE

2 RAKESH KUMAR BHAGAT AND DEVENDRA KUMAR DEWANGAN population in rhizosphere at different growth stages of paddy in Vertisol of Chhattisgarh involved a field experiment laboratory analysis conducted in the Department of Soil Science Agricultural Chemistry, College of Agriculture, Raipur (C.G.) during Kharif season of The experiment was carried out in Romized Block Design with 4 replications having treatments: T 1 (Control without fertilizer),, (100% N alone), (100% NPK+FYM), (50%NPK+green manure). A medium duration high yielding paddy variety Mahamaya was taken as crop. Rhizosphere microbial population at different growth stages of paddy were determined from surface (0-15 cm) soil samples collected. Microbial analysis : The soil samples were collected from 0-15 cm depth from each plot of rice crop in different stage viz., transplanting, tillering, panicle initiation harvesting used for the following method of microbial analysis. Population count study : Microbial population study was done by plate count method using serial dilution (Subba Rao, 1988). One g of soil sample was suspended in 9 ml of sterile water in a dilution tube (Tuladhar, 1983) shaken for 15 min. it was serial diluted by transfering 1 ml. from stock. Fresh tips were used for preparing serial a fresh sterile dilution (10-1 to 10-6 ). The different media were prepared used for isolation of micro-organisms viz., Nutrient agar media for bacteria, Rose Bengal agar media (Martin, 1950) for fungi, Kengnight agar media for actinomycetes Yeast manitol agar media for N 2 fixing bacteria.the media were sterilized at kg cm 2 pressure at 121 C for 15 min. 1 ml of desired dilution of freshly mixed suspension was transferred into the sterile Petridish using sterile tip of micro-pipette. One ml solution of 10-6 dilute was spread on specific media for particular microorganism, on which about 15ml of partially cooled appropriate medium was poured into each plate carefully thoroughly mixed. After the media got solidified inverted the plates were kept in an incubator at respective incubation temperature for different micro-organisms viz., 28 o C±2 C for fungi 25 o C±2 C for bacteria N 2 fixing bacteria. After specified period of growth (24 hrs for hetrotropic bacteria N 2 fixing bacteria 6-7 day hrs for fungi actinomycetes), colonies were counted populations were enumerated by using formula given by Schmidt Caldwell, (1967). No. of CFU x dilution Number of microbial population in 1g soil Dry weight of 1g moist soil x aliquot taken Research Findings Discussion The experimental findings of the present study have been presented in the following sub heads: Microbial population : Bacterial population : Data presented in Table 1 showed changes in bacterial population at different crop growth stages as affected by fertilizer application. The highest significant bacterial population (5.1 x10 6 CFU) was recorded under the treatment (100% NPK+FYM) at tillering stage, while the lowest significant bacterial population (2.2 x10 6 CFU) was found in T 1 The Table reveals that at transplanting stage there was no significant difference due to treatments (50% NPK+GM) i.e. they were at par. However, were significantly different from T 1,. Similarly at PI stage, the treatments were at par but they were significantly different from T 1,,. Similarly at harvesting stage, the treatment T 1,, were statistically at par each other. These findings are in close proximity with that of Nakro Dkhar (2010). Representative Petriplates showing population of bacteria in paddy rhizosphere soil can be seen in Plate 1. Table 1: Bacterial population ( 10 6 CFU g -1 rhizosphere soil) in different growth stages of paddy as influenced by continuous application of T 1= Control 3.4 a 3.9 a 3.7 a 2.2 a = 100% (RDF) 4.2 c 4.6 c 4.5 c 2.4 a = 100% N 3.8 b 4.1 b 4.0 b 2.3 a =100%(RDF)+FYM 4.7 d 5.1 e 4.9 d 2.6 a =50% (RDF) + GM 4.3 c 4.9 d 4.6 c 2.5 a S.E.± C.D. (P=0.05) Note. 1 The subscripts a, b, c, d e are showing significance of difference among different means at different growth stages of paddy as influenced by HIND AGRICULTURAL RESEARCH AND TRAINING INSTITUTE 275 Asian J. Soil Sci., (Dec., 2012) 7 (2) :

3 EFFICIENCY OF MICROBIAL POPULATION IN RHIZOSPHERE AT DIFFERENT GROWTH STAGES OF PADDY T 1 Plate 1: Bacterial population in rice field Plate 2: Fungal population in rice field Fungal population : Data presented in Table 2 depicts changes in fungal population at different crop growth stages as affected by fertilizer application the highest significant fungal population (3.1 x10 4 CFU) was noticed in, the plots treated with (100% NPK+FYM), while the lowest significant value of fungal population (2.0 x10 4 CFU) was recorded in control plot for all growth stages of the crop. The table reveals that at transplanting stage there was no significant difference in due to treatment (100% N) i.e. they were at par. However were significantly different from T 1,. Similarly at tillering PI stages, the treatments T 1, were at par also treatments at par with each other but significantly different. Similarly at harvesting stages, the treatments T 1 were at par also treatments, at par with each other but significantly different. These results are in agreement with the findings of Singh et al. (2007). Few Petriplate used for enumeration of fungi in rhizosphere soil can be seen in Plate 2. Actinomycetes population : Data presented in Table 3 indicated changes in actinomycetes population at different crop growth stages as affected by fertilizer application. The highest significant actinomycetes population (3.1 x10 4 CFU) in the plots applied with (100% NPK+FYM), while the lowest significant actinomycetes population (1.6 x10 4 CFU) was observed in T 1 The table reveals that at transplanting stage there was no significant difference due to treatment T 1 (control), (100% N) i.e. they were at par also treatments at par with each other but significantly different. Similarly at tillering stage, the treatments T 1 were at par also treatments, at par with each other but significantly different. Similarly at PI stage, the treatments T 1 were at par also treatments at par with each other but significantly different from. Similarly at harvesting stage, the treatment T 1,, were statistically at par each other. Similar results were recorded by Krishnakumar et al. (2005). Characteristic actinomycetes colonies form various treatments Table 2 : Fungal population (10 4 CFU g -1 rhizosphere soil) in different growth stages of paddy as influenced by continuous application of T 1= Control 2.1 a 2.2 a 2.1 a 2.0 a = 100% (RDF) 2.4 b 2.5 a 2.4 a 2.3 b = 100% N 2.3 b 2.4 a 2.2 a 2.1 a =100%(RDF)+FYM 2.9 d 3.1 b 3.0 b 2.5 b =50% (RDF) + GM 2.7 c 2.9 b 2.8 b 2.4 b S.E.± C.D. (P=0.05) HIND AGRICULTURAL RESEARCH AND TRAINING INSTITUTE 276 Asian J. Soil Sci., (Dec., 2012) 7 (2) :

4 RAKESH KUMAR BHAGAT AND DEVENDRA KUMAR DEWANGAN grown on Petriplates may be viewed in photograph (Plate 3). Plate 3: Actinomycetes population in rice field N 2 -fixing bacteria : Data presented in Table 4 depicts changes in N 2 -fixing population at different crop growth stages as affected by fertilizer application. The highest significant N 2 -fixing population (5.0 x10 3 CFU) was recorded with (100% NPK + FYM), while the lowest significant N 2 -fixing population (2.1 x10 3 CFU) was found in T 1 The table reveals that at transplanting tillering stages there was no significant difference in due to treatments T 1,,, i.e. they were at par. These findings are in close proximity with that of Selvi et al. (2004). Among the treatments, 100 per centnpk+fym showed higher microbial population followed by 50 per cent NPK+GM the lowest microbial population was observed under control treatment. In all the cases (bacteria, fungi, actinomycetes N 2 -fixing bacteria), all the treatments showed significant result over control. In the present study, it was observed that, the paddy soil treated with (100%NPK+ FYM) showed higher microbial population (bacteria, fungi, actinomycetes N 2 -fixing bacteria) at tillering stage of paddy crop, significant higher microbial population was recorded under (100%NPK+FYM) in comparison to other treatments. The attributed reason could be the enhanced organic carbon content of the soil as a result of organic manure application as compared to inorganic fertilizers alone. Besides this, the organic manure addition viz., (100%NPK+FYM) would have resulted in increased secondary micronutrients in the soil which might have helped to increase substrates for microbes. This observation is closely related to Nakro Dkhar (2010), Krishnakumar et al. (2005), Selvi et al. (2004), who mentioned that application of FYM increase microbial population significantly. Table 3 : Actinomycetes population (10 4 CFU g -1 rhizosphere soil) in different growth stages of paddy as influenced by continuous application of T 1= Control 2.2 a 2.4 a 2.3 a 1.6 a = 100% (RDF) 2.4 a 2.8 b 2.7 b 1.9 a = 100% N 2.3 a 2.6 a 2.4 a 1.7 a =100%(RDF)+FYM 3.0 b 3.1 b 3.0 c 2.1 a =50% (RDF) + GM 2.9 b 2.9 b 2.8 b 2.0 a S.E.± C.D. (P=0.05) Table 4: N 2-fixing bacteria (10 3 CFU g -1 rhizosphere soil) in different growth stages of paddy as influenced by continuous application of manure fertilizers T 1= Control 3.2 a 4.4 a 3.4 a 2.1 a = 100% (RDF) 4.1 a 4.8 a 4.6 c 2.9 c = 100% N 3.8 a 4.5 a 4.3 b 2.6 b =100% (RDF)+FYM 4.7 a 5.0 a 4.9 d 3.5 d =50% (RDF) + GM 4.5 a 4.8 a 4.5 c 3.0 c S.E.± C.D. (P=0.05) HIND AGRICULTURAL RESEARCH AND TRAINING INSTITUTE 277 Asian J. Soil Sci., (Dec., 2012) 7 (2) :

5 EFFICIENCY OF MICROBIAL POPULATION IN RHIZOSPHERE AT DIFFERENT GROWTH STAGES OF PADDY Table 5 : Grain yield (kg/ha) as affected by different treatments as influenced by Rice Grain yield (kg/ha) T 1= Control = 100% (RDF) = 100% N =100% (RDF)+FYM =50% (RDF) + GM a c b d c S.E.± C.D. (P=0.05) Grain yield : Data presented in Table 5 indicated that the grain yield of rice crop increased significantly due to application of (100%NPK+FYM), (50%NPK+GM), (100%NPK) (100%N), respectively over control. Among all the treatments the highest significant grain yield ( kg/ha.) recorded under (100%NPK+FYM), while the lowest significant grain yield was in T 1 (control) ( kg/ha) for all growth stages of the crop. Among all the treatments, (100%NPK+FYM) showed higher grain yield than (50% NPK+GM) followed by (100%NPK). The (100% N) treatment recorded significantly lower grain value than all other, (50% NPK+GM) (100% NPK+FYM) treatments but it was significantly higher than control treatment. The rice grain yield (4517kg/ha) obtained under combined application of (50% NPK+GM) was at par with the yield recorded under recommended dose of (100%NPK) fertilizer (4542kg/ha). The findings are in accordance with those of Singh et al. (2007) who also reported that increase in grain yield due to combined application of organic with inorganic fertilizer over application of chemical fertilizer. Literature Cited Doi, T., Matsumoto, H., Ohshita, N., Takemoto, Y. Shinada, T. (2006). Microflora analysis on hydrogen fermentation of feedstock wastes. J. Water Waste, 48: Krishnakumar, S., Saravanan, A., Natarajan, S.K., Veerabadran, V. Mani, S. (2005). Micobial population enzymatic activity as influenced by organic farming. Res. J. Agric.& Biol. Sci., 1: Nakro, N. Dkhar, M. S. (2010). Impact of organic inorganic fertilizers on microbial population biomass carbon in paddy field soil. J. Agron., 9: Sakai, M., Matsuka, A., Komura, T., Kanazawa, S. (2004). Application of a new PCR primer for terminal restriction fragment length polymorphism analysis of the bacterial communities in plant root. J. Microbiol. Methods, 59: Selvi, D., Santy, P., Dhakshinamoorthy, M. Maheshwari, M. (2004). Microbial population biomass in rhizosphere as influenced by continous intensive cultivation fertilization in a Inceptisol. JISS, 52(3) Singh, Y.V., Singh, B.V., Pabbi, S. Singh, P.K. (2007). Impact of organic farming on yield quality of basmati rice soil properties. Watt, M., Kirkegaard, J. A. Passioura, J. (2006). Rhizosphere biology crop productivity a review. Aust. J. Soil Res., 44: ******** ****** **** HIND AGRICULTURAL RESEARCH AND TRAINING INSTITUTE 278 Asian J. Soil Sci., (Dec., 2012) 7 (2) :