Assessing the Impact of Integrated Nutrient Management Practices on Growth and Yield Performance of Direct Seeded Rice in Dystrudepts of Nagaland

Rice (Oryza sativa L.) is a cereal grain that belongs to the family of Poaceae and is recognized as a supreme commodity to mankind. Rice plays a pivotal role in Indian agriculture and is the staple food for more than 70 percent of the population. Since Indian agriculture continues to be a gamble in monsoon, water scarcity for agricultural production has become a significant problem. Therefore, the direct seeding technique is a viable option to reduce unproductive water flows and is gaining acceptance by the growers day by day because of its low input. The DSR method does not require more labor and squeezes water consumption and production cost. Thus, DSR is a promising method technically and economically, which is an achievable alternative to transplanted rice.
               
On the other hand, soil is rightfully called the “soul of infinite life”; however, this soul has become dilapidated of late due to ill-agricultural practices being adapted to feed the ever-increasing mouths. Our agriculture’s sustainability and climate adaptability depends on what we put into our fields and what leaches from our field and gets added to our water and air. The needle is pointing at imbalanced nutrient management practices, which have ill effects on soil health deterioration. It is needed to feed our ever-increasing mouths, but this has to be done without further deteriorating our soils, climate or for that matter, human health. The path forward can start with balanced, integrated nutrient management and slowly pave the way towards adapting organic or bio-fertilizers as an alternative to chemical fertilizers (Choudhary et al., 2020). Soil health is deteriorating due to the excessive use of chemical fertilizers. Therefore, it is in dire need of soil fertility and productivity, which can only be done through judicious use of chemical fertilizers along with organics (Khan et al., 2009). Keeping in view of the above facts, the present investigation entitled, “Assessing the impact of Integrated Nutrient Management practices on growth and yield performance of Direct Seeded Rice in dystrudepts of Nagaland” was carried out for studying the growth and yield parameters of direct seeded rice.

The investigation was conducted at the experimental farm of the School of Agricultural Sciences (SAS), Medziphema Campus, Nagaland University, during kharif season of 2019 and 2020.Geographically, the experiment site is situated at 20°45'4" N latitude and 93°53'0" E longitude at of 310 m above mean sea level. The soils of the experimental site are dominated by the soil order of Inceptisol with low base saturation with a “Udic” soil moisture regime; therefore, it was laid down in “Dystrudepts” great groups. A well-drained and sandy clay loam texture characterized the soil of the experimental plot.
       
The field experiment was laid out in Randomized Block Design with three replications and twelve treatments with a plot size of 3 m × 2 m, each maintaining 20 cm ´ 10 cm spacing. The treatment details are T₁: Control, T₂: RDF (120 kg N ha^-1 + 40 kg P₂O₅ ha^-1 + 30 kg K₂O ha^-1), T₃: 100% RDF +PSB, T₄: 100% RDF + 2 t FYM ha^-1, T₅: 100% RDF + 2 t FYM ha^-1 + PSB, T₆:  75% RDF + PSB, T⁷: 75% RDF + 2 t FYM ha^-1, T₈: 75 % RDF + 2 t FYM ha^-1 + PSB, T₉: 50% RDF + PSB, T₁₀: 50% RDF + 2 t FYM ha^-1, T11: 50% RDF + 2 t FYM ha^-1 + PSB, T₁₂: 109 kg N ha^-1 + 30 kg P₂O₅ ha^-1 + 46 kg K₂O ha^-1 (SSNM).
       
Land preparation was carried out, and well-decomposed FYM was broadcasted in the required plots @ 2 tones ha^-1 one month before sowing. The calculated amount of fertilizer doses was applied to each plot. Seed treatment of phosphorus solubilizing bio-fertilizer (PSB) at the rate of 200 g per 10 kg seeds as per the treatments was done before sowing. The rice cultivar (Kuntsaire) was broadcasted in each plot @ 80 kg ha^-1.
       
Growth parameters such as plant height, number of leaves plant^-1, and number of tillers plant^-1 of five random plants were selected from each plot and tagged for recording. The plant height was measured in centimeters (cm) from the ground level to the tip of the plants. The number of leaves plant^-1 and tillers plant^-1 was recorded from the tagged plants. Dry matter accumulation was recorded by selecting five random plants from each plot. The samples were sun dried followed by hot air oven dried at 65-70°C and the average dry weight was recorded. The crop growth rate (CGR) at different growth stages was calculated by using the dry matter accumulation (g) of plants for each plot at successive growth.
               
Yield attributes such as panicle length, number of panicles plant^-1, and number of grains panicle^-1 were recorded from the tagged plants of each plot at the time of harvest. After threshing and cleaning, the grain and straw yield were obtained from their respective plots.

Growth attributes
 
Table 1 clearly indicated that the growth parameters viz. plant height, number of leaves plant^-1, number of tillersplant^-1 and dry matter accumulationplant^-1 responded significantly to the combined application of nutrients during both the years of investigation. T₅ (100 % RDF + FYM @ 2 tones ha^-1 + PSB) treatment recorded the highest growth attributes which is found to be at parity with T₄ (100 % RDF + FYM @ 2 tones ha^-1) and is superior than the rest of the treatments. On the other hand, significantly lowest value of growth attributes was prominently noticed in the control treatment (T₁) as there was no external source of nutrients.
 

       
Treatment with higher level of fertilizers combined with organic manure and PSB attained higher plant height which could be the indication of adequate nutrient supply which resulted in better elongation of internodes, good establishment of roots and vegetative growth throughout the crop cycle (Geetha et al., 2020). The FYM application also enhanced the expansion of algal cells as well as the uptake of nutrients besides facilitating as substrate for the PSB thus increased the plant height. The results were in conformity with Nanda et al., (2015). Likewise, the number of leaves plant^-1 also increased with the combined application of higher levels of RDF along with FYM and PSB when compared with other treatments. Singh et al., (2021) also reported that more leaves was produced in the treatments where an adequate amount of major nutrients was applied, which resulted in prolific root growth for supply of nutrient and water and hence brought about greater accumulation of photosynthates which enhanced the crop growth. In the case of the number of tillers plant^-1, the increase in plant height must have enhanced the photosynthetic area for photosynthesis in plants, which in turn helped in formation of new tillers. The tiller production at higher levels of nutrients may be due to better crop nutrition, which has also been reported by Bajpai et al., (2022). The dry matter accumulation is considered to be the reliable index of crop growth which might have increased due to the cumulative effect of an increase in different growth characteristics like plant height, number of tiller plant^-1, and number of leaves plant^-1. These findings are in conformity with Kumari et al., (2019) and Shinde et al., (2017). The crop growth rate was significantly influenced due to integrated nutrient management at 30-60 DAS, where a similar pattern of CGR was also observed by Laila et al., (2022) but no significant result was noted after 60 days.
 
Yield and yield attributes
 
Significant variations were noticed in yield attributing characters where nutrients were applied in integrated manners. Integrated nutrient management practices significantly boosted the panicle length, number of panicles plant^-1, number of grains panicle^-1, grain and straw yield in both the years (Table 2) where maximum value was recorded in treatment T₅ receiving the highest value of nutrients in combination with FYM and PSB, which is found to be at par with treatment T₄ (100 % RDF + FYM @ 2 tones ha^-1)which is significantly superior from the rest of the treatments. The lowest value of grain yield (22.16 q ha^-1) and straw yield (40.88 q ha^-1) was recorded in control treatment (T₁).
 

       
The significant increase in panicle length could be due to the plant’s higher absorption of different fertilizer, which favored producing longer panicles where similar results were reported by Mondal et al., (2015). According to Bajpai et al., (2022), the early emergence of primary and secondary tillers at the vegetative stage being supported with adequate proper nutrient supply and translocation of food materials towards reproductive parts contributed to a higher number of panicle plant^-1. Continuous and even distribution of nutrients at peak demand resulted in more grains panicle^-1, which attributed to better translocation of carbohydrates from source to sink (Shalini et al., 2017).
               
Behera and Pany (2021) opined that the increase in yield might be due to the higher availability of nutrients and optimum soil properties in the plots receiving inorganic and organic fertilizers. Neti et al., (2022) documented that INM boosted the vegetative growth of the plants, which increased the straw yield, thereby resulted in better productivity. However, the harvest index did not respond to any of the treatments.

Based on the study, it was evident that integrated nutrient management positively had significant impact on enhancing the growth parameters, yield attributes, and yield of direct-seeded rice. The application of 100% RDF + FYM @ 2 t ha^-1 + PSB (T₅) was recorded to perform the best therefore, it is recommended to integrate the use of organic manures in addition to chemical fertilizers to meet the nutrient needs of the direct seeded rice.

None.