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Indian Journal of Pure & Applied Biosciences (IJPAB)
Year : 2020, Volume : 8, Issue : 3
First page : (408) Last page : (420)
Article doi: : http://dx.doi.org/10.18782/2582-2845.7959

Influence of Adopting Nutrient Management Practices in Rice Crop (Oryza sativa L.) Under Different Establishment Methods

Amit Pant^1*, P.C. Pandey², Shanker Dutt Thapliyal³ and Rupanshi Aswal^4
1,3,4M.Sc. Scholar and ²Professor
Department of Agronomy, G.B.P.U.A. & T., Pantnagar
*Corresponding Author E-mail: amitepnt01@gmail.com
Received: 13.02.2020  |  Revised: 17.03.2020   |  Accepted: 25.03.2020 

 ABSTRACT

The present investigation was carried out to find the effect on growth and yield of Rice (Oryza sativa L.) by adopting nutrient management practices under different establishment method. The experiment was conducted in A2 block at N. E. Borlaug Crop Research Centre, G.B. Pant University of Agriculture and Technology, Pantnagar, District Udham Singh Nagar, Uttarakhand. The treatments consisting three establishment methods in main plots and five nutrient management practices in sub plots (fifteen combination) was laid out in split plot design (SPD) with three replications. The result revealed that, the values for plant height were not influenced by establishment methods however tallest plants were obtained under transplanting method at harvest. Application of 150%RDF led to tallest plants but various nutrient management treatments could not establish significant effect on plant height at harvest. Number of shoots/m2 was significantly less due to transplanting method. RDF+5tFYM/ha, RDF and RDF (LCC based N) caused similar but significantly more number of shoots/m2 compared to remaining treatments at harvest.The lowest sterility (%) was found in transplanting method and higher in aerobic and wet-direct seeded methods. RDF+5tFYM/ha recorded lower sterility (%) compared to remaining treatments. Transplanting method of establishment and application of RDF+5t FYM/ha being at par with RDF (LCC based N) significantly increased the yield attributes, grain yield, straw yield and biological yield.

Key words: Rice Crop (Oryza sativa L.), Nutrient Management, Establishment Methods.

Full Text : PDF; Journal doi : http://dx.doi.org/10.18782

Cite this article: Pant, A., Pandey, P.C., Thapliyal, S.D., & Aswal, R. (2020). Influence of Adopting Nutrient Management Practices in Rice Crop (Oryza sativa L.)  Under Different Establishment Methods, Ind. J. Pure App. Biosci. 8(3), 408-420. doi: http://dx.doi.org/10.18782/2582-2845.7959

INTRODUCTION

MATERIALS AND METHODS

The experiment was conducted in A2 block at N. E. Borlaug Crop Research Centre, G.B. Pant University of Agriculture and Technology, Pantnagar, District Udham Singh Nagar, Uttarakhand during the kharif season of 2015. This experiment was laid out in spilt-plot design keeping establishment method in main plots and nutrient management practices in sub-plots with three replications. The details of treatments in this study are given below:
Treatments:- (split plot design)
Establishment methods (Main Plot)
T1          :              Aerobic (Direct seeded rice)
T2          :              Wet-direct seeding
T3          :              Transplanting
Nutrient management practices (Sub Plot)
F1          :  RDF (Recommended dose of fertilizer) (120:60:40) N: P2O5: K2O kg/ha
F2          :  75%RDF (90:45:30) +FYM/ha (Equivalent to 25% N dose)
F3          :   150% RDF (180:90:60)
F4 :           RDF (90:60:40) (LCC based N application)
F5 :          RDF (120:60:40) + 5 tonnes FYM/ha (Location specific)
Note: - In Direct seeding and Wet direct seeding N was applied as ¼ basal + ½ tillering + ¼ PI and in Transplanted rice N  was applied as ½ basal + ¼ tillering + ¼ PI.
Variety : HKR-47, Replication : 3, Treatments : 15, Total No. of plots  : 45
Observation and sampling procedures
i). Pre-harvest crop growth studies:- In aerobic plot on one side, leaving the two rows as border, one meter row length of crop in the third row was marked from north and south direction for recording observations on the plant height, number of shoots and post-harvest studies. Also in wet-direct seeded plot, 0.5m x 0.5m area in each corner after leaving 0.5m border on both side of the plot were marked for recording above observations. In transplanted rice plots total 16 hills, 4 from each corner in third and fourth row were marked for observations of plant height, number of shoots and post-harvest studies. ii). Plant height:-The height of four randomly selected plants in net plot area at 30, 60, 90 days after sowing/ transplanting and at maturity was measured with a meter scale from the ground level to the tip of top most leaf at initial stage of crop growth and after heading up to the tip of the top most panicles, within one meter row length marked for observation in the beginning in each plot in aerobic rice plot and in wet-direct seeded plot from an area half meter quadrate marked for observation. While in transplanted plots, from the randomly selected 4 hills located at four corners plant height was measured with a meter scale.  The mean of 4 plants was reported as cm/plant at 30, 60, and 90 days after sowing/transplanting and at maturity. iii). Number of shoots:-Total number of shoot were counted from sampling area marked for observation at 30, 60 and 90 days after sowing/transplanting and at maturity and then expressed as number of shoots/m2.
Post- harvest studies (Yield attributing characters):-
i). Number of panicles:- The number of panicles was counted from the marked 2 m row length in aerobic, half meter quadrate marked in wet-direct seeded and 16 hills marked in transplanted rice and were expressed as number of panicles/m2. ii). Panicle length:- At maturity of the crop, 10 representative panicles were randomly selected from sampling area and length of each panicle was measured starting from the base (last node of the culm) of the first branch of rachis to the top of the panicle and is expressed in cm/panicle. iii).Total number of spikelets:- The crop plants from marked sampling area were taken, for study after counting the panicle number. All the filled and unfilled spikelets were separated manually and weighed. A sample of 250 grain filled and 500 grain unfilled spikelets were weighed separately from each plot and converted to 1000-grain weight. The number of filled and unfilled spikelets was obtained by the following formula:                   
(d) Sterility percentage was calculated by following formula:

RESULTS AND DISCUSSION

Plant height
The values for height (cm) recorded at various stages are presented in Table 1.
The rice grew taller as the age of crop advanced and the height was similar in wet-direct seeded and aerobic methods, but increased significantly under transplanting method compared to other methods. Also, at all other stages the transplanting method of rice cultivation was significantly superior over other establishment methods in respect of plant height except at maturity. At maturity, these differences were not found however, the shorter plants were recorded in aerobic method at all the crop growth stages.
Among nutrient management treatments no significant difference in plant height was observed at all the growth stages except at 60 DAS/DAT where RDF+5t FYM/ha, being at par with RDF (LCC based N), caused significant increase in plant height compared to other treatments.

Table 1: Plant height (cm) as influenced by the treatments at different crop growth stages

Number of shoots
Data pertaining to number of shoots/m2 at various stages are given in Table 2 .At 30 days stage, significantly more shoots were observed in transplanting method compared to remaining methods while at other stages wet-direct seeded and aerobic methods remained at par but resulted in significantly more shoots. Due to different nutrient management treatments no effect on the number of shoots was noticed at 30 days stage while at 60 and 90 days stages different nutrient management treatments differed significantly. At 60 days stage, RDF treatment caused significantly more shoots compared to remaining treatments. At 90 days stage RDF+5tFYM/ha being at par with RDF and RDF (LCC based N) treatments caused significant enhancement in number of shoots compared with other treatments.
The interaction between establishment methods and nutrient management with respect to number of shoots/m2 was significant at all the stages.
            At 30 days stage under aerobic method the treatment RDF being at par with 75%RDF+FYM (equivalent to 25%N), resulted in significantly more shoots but these differences disappeared under wet-direct seeded method. Under transplanted method RDF resulted in significantly less shoot compared to other treatments which were statistically similar. Under all the nutrient management treatments, number of shoots was significantly more in transplanting method compared to remaining methods.
            At 60 days stage, under wet-direct seeded method, the treatment RDF (LCC based N) being at par with RDF+5tFYM/ha and RDF, caused significantly more shoots compared to remaining nutrient management treatments. Under transplanting method, RDF+5tFYM/ha being at par with RDF (LCC based N) and RDF, recorded significantly more shoots compared to remaining treatments. Under aerobic method, these differences due to nutrient management treatments disappeared.
            At 90 days stage, under aerobic method, RDF resulted in significantly more shoots compared to remaining nutrient management treatments while under wet-direct seeded method 150%RDF caused significantly less shoots compared to other nutrient management treatments, which were statistically similar. Under transplanting method, RDF+5tFYM/ha caused significantly more shoots compared to remaining treatments while RDF (LCC based N) caused significantly more shoots compared to 75%RDF+FYM (equivalent to 25%N) and 150%RDF. Under all the nutrient management treatments the number of shoots was similar in wet-direct seeded and aerobic methods but significantly more than transplanting method while at maturity under aerobic method the number of shoots were similar due to 150%RDF, RDF (LCC based N) and RDF+5tFYM/ha but significantly more than 75%RDF+FYM (equivalent to 25%N). Under wet-direct seeded method RDF caused significantly more shoots compared to remaining nutrient management treatments. Also 75%RDF+FYM (equivalent to 25%N) and 150%RDF caused similar number of shoots but significantly less than RDF (LCC based N) and RDF+5tFYM/ha. Under transplanting method RDF+5tFYM/ha caused significantly more number of shoots compared to all other nutrient management treatments. Under all the nutrient management treatments wet-direct seeded and aerobic methods resulted in similar number of shoots compared to transplanting method, except under 150%RDF, where wet-direct seeded method resulted in significantly more number of shoots than transplanting method and significantly less than aerobic method.

Table 2: Interaction effect of establishment methods and nutrient management treatments on number of

Yield attributes of rice
Number of panicle      
The influence of different establishment methods on number of panicles/m2 was significant (Table 3). The aerobic method registered significantly higher number of panicles than that obtained under transplanting method which registered significantly less panicles compared to other establishment methods. However, aerobic method was at par with wet-direct seeded method in respect of number of panicles. Various nutrient management treatments also had a significant effect on the number of panicles. The treatment comprising RDF+5tFYM/ha caused significantly higher number of panicles compared to RDF (LCC based N), 150%RDF and 75%RDF+FYM (equivalent to 25%N). However, RDF+5tFYM/ha treatment was at par with RDF.The interaction between establishment methods and nutrient management treatments for number of panicles was significant. Under aerobic method, 150%RDF treatment caused significantly more panicles compared to 75%RDF+FYM (equivalent to 25%N), but found at par with other treatments. Under transplanting method significantly higher number of panicles were obtained due to RDF+5tFYM/ha treatment and lowest being in RDF treatment. Under wet-direct seeded method, the treatment RDF, being at par with RDF (LCC based N) and RDF+5tFYM/ha, caused significantly more number of panicles compared to remaining treatments. Under nutrient management treatments, aerobic and wet-direct seeded methods resulted in similar panicles but significantly higher than transplanting methods. Under 150%RDF panicles were significantly less due to transplanting method compared to remaining methods.

Table 3: Interaction between different Establishment method and nutrient management treatments on panicle number/m2

Panicle length of rice crop was not affected by different establishment methods and nutrient management treatments. However, transplanting method resulted in higher values of panicle length compared to remaining treatments. Statistically significant difference in grain weight/panicle was noticed due to establishment methods. Transplanted method caused significantly higher grain weight/panicle as compared to remaining treatments. Among nutrient management treatments, RDF+5tFYM/ha treatment being at par with RDF (LCC based N) caused significantly higher grain weight/panicle compared to other treatments and lowest grain weight/panicle was observed due to RDF treatment. The difference in the number of filled spikelets was statistically higher due to transplanting method compared to remaining methods. Wet-direct seeded and aerobic methods resulted in statistically similar filled spikelets. Application of RDF+5tFYM/ha caused similar filled spikelets to that of RDF (LCC based N) but significantly more than other treatments. RDF treatment alone caused significantly less filled spikelets compared to remaining nutrient management treatments. The difference amongst the establishment methods was significant in minimizing the sterility of rice spikelets. The significantly lower sterility was noticed in transplanting method compared to aerobic method. However, aerobic and wet-direct seeded methods resulted in similar sterility of spikelets. Among nutrient management treatments RDF caused significantly more sterility, while RDF+5tFYM/ha caused significantly less sterility of rice spikelets.
From above results on yield attributes, it was observed that transplanting method registered higher mean panicle length, significantly higher 1000-grain weight and filled spikelets and also significantly lower number of unfilled spikelets and lesser sterility and found superior to wet-direct seeded and direct seeded methods of rice cultivation. The superiority of transplanting method over establishment method might be attributed to fairly spaced planting of rice seedling facilitating better root growth and better canopy structure with high leaf area resulting in greater light interception and better availability of nutrients in submerged field compared to aerobic condition. These findings are alike to earlier finding (Aslam et al., 2008; Kanungo & Roul, 1994; Sharma & Mitra, 1991). Due to these factors rice crop under transplanted system produced higher filled spikelets which have directly proved helpful in reducing the panicle sterility and also helped in increasing the 1000-grain weight of rice. Delayed senescence with enhanced photosynthesis was also responsible for supplying more assimilates toward the roots for maintaining their higher activity. These features might also have contributed to the improvement in grain filling and reducing the sterility in spikelets. Lower 1000-grain weight and lower number of filled spikelets in aerobic and wet-direct seeded may probably be due to poor root development of plants under drilled/broadcasting method respectively. Transplanting method increases the number of filled spikelets and also the 1000-grain weight through optimum utilization of resources which had direct bearing on reduced sterility and increased grain weight (Luzes, 1991; Farooq et al., 2011; Gitsopanios and Williams, 2004; Awan et al., 1989; Song et al., 2009 and Sudhir et al., 2007; Jaiswal and Singh, 2001).
Among, nutrient management treatments in the present investigation, it was observed that RDF+5tFYM/ha treatment caused higher 1000-grain weight, lower sterility and superiority of other yield attributing characters compared to RDF and other treatments consisting inorganic sources of nutrients. It might probably be due to the better integration of inorganic and organic source of fertilizer, which facilitates longer time availability of both macro and micro nutrients to crop during all the important developmental stages of rice crop (Kumar, 2001) and ultimately helped in producing higher healthy spikelets with higher grain weight and reported that application of organic nutrient sources in conjunction with inorganic nutrient sources exhibit a significant increase in yield contributing attributes compared to fertilization through inorganic sources alone (Singh et al., 1996). Integration of farm yard manure with inorganic sources would have resulted in slow release of nutrient and increased availability which in turn might have enhanced more photosynthates production and the translocation from source to sink and improved the yield attributing characters (Ramamoorthy et al., 2000 and Balamurali, 2006). The supply of required nutrients through FYM or other inorganic source facilitated balanced nutrition to crop which might have resulted in enhanced yield attributes in rice (Jayabal et al., 1999). The inorganic nitrogen nourished the plant at initial stage and boosted the growth, while the incorporated FYM released the nutrients slowly and made available upto reproductive stages of crop (Dahiphale et al., 2003). The decomposition of applied FYM might have solubilised the soil native phosphorus and potassium which led to availability of balanced nutrients (Subramanian, 1997). FYM with inorganic N leads to higher uptake of phosphorus due to the solubilisation of insoluble phosphorus as phosphorus plays a vital role in the translocation of assimilates to panicles and also as a constituent of protoplasm (Ishizuka, 1971). This explains the reason for the increased length of panicle, panicle weight and reduced sterility, which ultimately helped to produce higher yield attributing characters in RDF+5tFYM/ha treatment compared to inorganic source of nutrient alone (RDF).

Table 4: Panicle length (cm/panicle), grain weight/panicle (g), 1000-grain weight (g), filled spikelets/m2 and sterility (%) as influenced by the treatments

Yield of rice crop
Data pertaining to grain yield, straw yield, biological yield and harvest index are presented in Table 5.
Grain yield
Grain yield was significantly higher when rice crop was transplanted compared to wet-direct seeded and aerobic method. However, wet-direct seeded and aerobic methods resulted in similar grain yield. Loss in grain yield due to aerobic (5,497 kg/ha) and wet-direct (5,633 kg/ha) seeded methods accounted for 8 and 6 per cent compared to transplanting method.
Among nutrient management treatments RDF+5tFYM/ha, being at par with RDF (LCC based N), caused significantly higher grain yield while RDF alone caused significantly lower grain yield of rice compared to remaining treatments.
With the transplanting method the main factor responsible for the yield enhancement in these trials was longer panicles with more grains, significantly better grain filling, reduced sterility and a significant increase in grain weight. Transplanted rice had greater percentage of filled spikelets and increased grain weight than did rice grown under wet-direct and direct seeded methods. As, in wet-direct and aerobic methods a significantly greater number of unfilled spikelets had occurred, which led to significantly lower grain yield than that of transplanting method (Aslam et al., 2008). These observations are also supported by significant positive correlation of yield attributes viz. 1000-grain weight (r =0.693), filled spikelets (r = 0.959) and grain weight/panicle (r = 0.748) (Table 16). Competition for weeds during early stage of growth and less moisture under aerobic and wet-direct seeded might have been the reason for low grain yield. Increased grain yield under transplanting method mainly due to lesser weed problem and also attributed to good crop conditions, more availability of nutrients etc.
Further, the increased availability of nutrients to rice crop under transplanting method might be attributed to better spacing and lesser plant to plant competition for resources as compared to higher inter and intra-plant competition for resources under aerobic and wet-direct seeded method due to drilling/broadcasting of seeds where overcrowding persisted till harvest. These findings are supported by the results reported by Saikia et al. (1992) and Jaiswal and Singh (2001). This also might be due to better root development in transplanting method than in aerobic and wet-direct seeded methods which led to higher grain weight and reduced sterility in transplanted rice. These results are in lines with the findings of Luzes (1991) and Farooq et al. (2011).     
Increase in grain yield due to RDF+5tFYM/ha was 14% compared to RDF alone. The treatment 75%RDF+FYM (equivalent to 25%N) also enhanced the grain yield over RDF treatment which was 5.5% more than RDF.
These effects might be due to the contribution of yield components such as productive tillers per, 1000-grain weight, higher filled spikelets and lower sterility. The regulated supply of nitrogen to rice crop through slow mineralization process with FYM helps in providing better physical condition for plant growth (Nambiar & Abrol, 1989). Chemical fertilizers offers, nutrients which are readily soluble in soil solution whereas nutrient availability from organic sources is due to microbial action and improved physical condition of soil (Sarker et al., 2004). Also, when the inorganic fertilizers are applied along with organics, the nutrient release becomes slow making long term availability of nutrients to plants. The increase in productive tillers, filled spikelets and reduced sterility in response to application of organic and inorganic sources to provide nutrients was probably due to enhanced availability of nutrients (Muhammad, 2008 and Mirza et al., 2010). In present experiment higher number of productive shoots and spikelets were observed in RDF+5tFYM/ha treated plots which also contributed to the increased grain yield. Apart from this, several rice workers observed significant increase in grain yield of rice with the use of FYM with inorganic nutrient sources (Salem, 2006; Miller, 2007 and Rakshit et al., 2008).
        Straw yield due to transplanting method, being at parwith aerobic method, resulted in significantly higher straw yield compared to wet-direct seeded method. However, wet-direct seeded and aerobic methods resulted in statistically similar straw yield. Different nutrient management treatments significantly influenced the straw yield. Use of RDF+5tFYM/ha caused similar straw yield to that of 150%RDF and RDF (LCC based N), but significantly higher than other treatments. Straw yield was significantly less due to RDF compared to remaining treatments. Straw yield under transplanting method was 4% more compared to wet-direct seeded method which might be due to higher plant height and use of aged seedlings (Rajput et al., 1995; Reddy and Shivraj, 1999 and Azad & Leharia, 2001) and differences were significant. The straw yield due to the treatment receiving nutrients through RDF+5tFYM/ha was 13% more than RDF. This might be due to favourable soil conditions and synchronized release of nutrients throughout the crop growth period resulted in enhanced yield attributes which in turn increased straw yield. These findings are supported by earlier findings (Murali and Setty, 2004 and Dahiphale et al., 2003). While, Biological yield was significantly higher due to transplanting method compared to other two establishment methods. However, wet-direct seeded and aerobic methods resulted in statistically similar biological yield. Application of RDF+5tFYM/ha resulted in similar biological yield to that of 150%RDF and RDF (LCC based N), but significantly higher than other treatments. RDF alone caused significantly less biological yield compared to remaining nutrient management treatments.There was 5.1% increase in biological yield due to transplanting method compared to aerobic method. The increased biological yield under transplanting method might be due to increased value of yield attributes (plant height, 1000-grain weight, filled spikelets and straw yield) as it is evident for significant positive correlation of 1000-grain weight (r = 0.602), filled spikelets (r = 0.940) with biological yield (Table 16). This result is in accordance with the findings of Ebaid and El-Refaee (2007). A significant difference in yield attributes and straw yield as affected by combination of FYM and inorganic fertilizer has been reported by Murali & Setty (2004).
            Transplanting method of rice cultivation registered significantly high harvest index compared to aerobic method but remained statistically at par with wet-direct seeded method. However, aerobic and wet-direct seeded methods registered similar harvest index. There was no difference in harvest index due to nutrient management practices. More harvest index resulted under transplanting method might be due to more grain yield which has direct influence on the harvest index in rice crop. Also, the similar results of higher harvest index under transplanting method than aerobic rice cultivation method was reported by Ehsanullah et al. (2000).

Table 5: Grain yield (kg/ha), Straw yield (kg/ha), biological yield (kg/ha) and Harvest index (%) as influenced by the treatments

CONCLUSION

Based on above studies, it is concluded that under normal condition, transplanting method along with application of RDF+5tFYM/ha and RDF (LCC based N) can be recommended for better gowth and yield.

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