Efficiency of Factor Productivity and Effect of Individual Input of Production on Growth, Yield and Economics of Soybean [Glycine max (L.) Merrill] Production

Soybean (Glycine max (L.) Merill) has become the most important oilseed crop of India in terms of both area and production and is significantly contributing to country’s edible economy. In India it is grown over an area of 11.44 million hectare with a production of 12.04 million tonnes and average productivity of 1050 kg ha^-1 (Anonymous, 2022). In India average productivity is low as compared world average (1600 kg ha^-1) (Anonymous, 2023). Soybean mainly grown in the rainfed condition and it is important for the livelihood of small and marginal farmers. Soybean contributes 43 per cent to the total oilseeds and 25 per cent to the total oil production in India and ranks fourth in respect to production of soybean in the world (Tomar et al., 2018 and Kumawat et al., 2021).
       
In India, average productivity of soybean is low due to lack of seed treatment with bio fertilizers, lack of weed management due to unavailability of labour or continuous rain, lack of sufficient soil moisture due to long dry spells during crop growth period, imbalanced nutrition, improper pest and disease management etc., affect the seed yield and productivity of soybean (Jaybhay et al., 2018). In general, total annual loss in agriculture produces, weeds account for 45%, insect 30%, disease 20% and other pests 5% (Rani and Raju, 2020). Vagaries of monsoon and prolonged dry spells affect crop growth and yield and significantly in Dharwad region of Karnataka. Even under normal rainfall situation crop failures are occurring due to moisture stress due to occurrence of dry spells occurred particularly during critical crop growth stages (Verma et al., 2018). For sustainable production, suitable in-situ conservation practices may ensure higher productivity by saving the crops during limiting and non-limiting moisture condition through safe disposal of runoff or its retention for profile moisture as and when required. Hence, it is necessary to exploit the technologies for in-situ moisture conservation like tillage, land configurations, mulching etc. (Rajput et al., 2009 and Mohanty et al., 2017).
       
The success of soybean cultivation depends upon the factors of production, including non-monetary and monetary inputs, which plays a crucial role in the sustainable yield of this crop. Soybean requires optimum weather conditions, fertile and nutrient-rich soil, optimum cultivation and management practices to complete the growth and development (Agarwal et al., 2013). Seed yield and productivity declines if the production elements required for soybean crop are lacking and even result complete failure of the soybean crop as the severity prolongs. This turns to high economic loss to the soybean farming community (Jaybhay et al., 2022). Hence, optimum use of the resources for production such as., land, water, soil and weather, etc., along with integrated crop production factors, add to higher soybean yield (Jaybhay et al., 2018).
       
Factors of production and integrated management practices determine the success of crop husbandry for getting a sustainable yield of the crops. Only few of the literature was suggested that, soybean grown with full practice gave significantly higher seed yield and net income, over omission of RDF and weed management. Further crop output efficiency in terms of partial factor productivity and agronomic efficiency was higher with full practice (Jaybhay et al., 2022). Information on the yield gap arising due to the absence/lack of individual crop management practices and quantifiable yield loss due to it is lacking in Northern Transition Zone of Karnataka.
       
Taking all these above factors into account, the current study was conducted over three years to assess how various crop management practices would impact on growth, yield and yield parameters, economics and crop output efficiency of partial factor productivity and agronomic efficiency of applied nutrients under rainfed conditions. 

Experimental site
 
Field experiments were conducted during the kharif season of 2020, 2021 and 2022 at All India Co-ordinated Research Project (AICRP) on Soybean, Main Agricultural Research Station, University of Agricultural Sciences, Dharwad, Karnataka, India under rainfed conditions. Dharwad is located at 15°17' North latitude and 70°05' East longitude with an altitude of 678 m above the mean sea level (MSL). It is located at Zone-8 i.e. Northern transitional zone and receives an annual rainfall of 800 to 1000 mm distributed throughout the growing season. The details of experimental site characteristic (Table 1) and meteorological data of study area are presented in Fig 1.
 

 

 
Experimental design and treatment details
 
The experiment was conducted in randomized block design with seven crop management practices with three replications. T₁. Full package (Seed treatment, seed inoculation, RDF, weed management, insecticide application, Ridge and furrow sowing), T₂. Full package - seed treatment, T₃. Full package - seed inoculation, T₄. Full package - RDF, T₅. Full package - weed management, T₆. Full package - insecticide application and T₇. Full package - Ridge and furrow sowing. The net plot size of the experimental site was 2.4 × 4.6= 11.04 m². The cultivar of soybean used in the study was MACS 1188. The treatment details on full package given in Table 2.
 

 
Collection of data on growth, yield and its components of soybean
 
Observations were recorded on number of branches per plant, total dry matter production, number of pods per plant and test weight. Grain and straw yield were calculated based on the yield obtained from each net plot and converted into to kg ha^-1 and also economics workout.
 
Crop output efficiency in terms of partial factor productivity and agronomic efficiency
 
PFP and AE was determined as per the formulae given by Mengel and Kirkby (2001).
   
Where:
PFP- Partial factor productivity.
   
Where:
AE- Agronomic efficiency of applied nutrients.
 
Statistical analysis
 
The statistical analysis of data on various recorded parameters of growth, yield and economics was done by using randomized block design as described by Gomez and Gomez (1984).

Growth attributes of soybean
 
Pooled data of three years presented in Table 3 revealed that the different crop management practices/treatments, significantly influenced the growth parameters viz., plant height, number of branches per plant and total dry matter production at 60 DAS. Among the different treatments, full package (T₁) recorded significantly higher plant height (65.80 cm), number of branches per plant (5.85) and total dry matter production (69.52 g plant^-1) at 60 DAS. However, it was on par with full package excluding seed treatment (T₂). Whereas, significantly lower plant height (54.12 cm), number of branches per plant (4.42) and total dry matter production (56.85 g plant^-1) was noticed in full package excluding weed management (T₅). The higher growth attributes which might be due to efficiently crop management practices resulted in higher dry matter production. The similar results are close conformity with the findings of Jaybhay et al., (2022).
 

 
Yield attributes and yield of soybean
 
Significantly higher yield attributes viz., number of pods per plant (76.0), seed yield per plant (32 g) and test weight (14.6 g) and seed yield (2277 kg ha^-1) was recorded in full package (T₁). However, it was on par with full package excluding seed treatment (T₂) and full package excluding ridge and furrow sowing (T₇). Whereas, lower number of pods per plant (61.0), seed yield per plant (24.78 g) and test weight (13.5 g) and seed yield (1889 kg ha^-1) recorded in full package excluding weed management practice (T₅) (Table 2 and 3) (Fig 2). Increase in seed yield under treatment T₁ over the T₅ was 17.03 per cent and over T₄ it was 11.15 per cent. Increment in yield and yield attributes due to full package supported by the essentiality of optimum cultivation practices required for obtaining the higher yield and evidenced the importance of individual cultivation practice to harvest maximum yield. The similar results with the findings of Jaybhay et al., (2022) and Meena et al., (2022). The yield gap in terms of yield reduction per hectare determined over the treatment full package was recorded maximum under full package excluding weed management (388.0 kg ha^-1) and full practice excluding RDF (254 kg ha^-1) followed by full practice excluding insecticide application (233 kg ha^-1). However, the least yield gap was recorded under full practice excluding seed treatment (33 kg ha^-1), which showed it has least effect on soybean seed yield than other management practices (Table 4). The similar results are close conformity with the findings of Jaybhay et al., (2022).
 

 

 
Economics of soybean
 
Economics of different treatments are presented in Table 4. The pooled data of three years, observed that, significantly higher gross returns (Rs. 97843 ha^-1) and net returns (Rs. 57043 ha^-1) was recorded in crop management with full package (T₁). However, it was on par with full package excluding seed treatment (T₂) and full package excluding ridge and furrow sowing (T₇). Whereas, significantly lowered gross return (Rs. 80590 ha^-1) and net returns (Rs. 44695 ha^-1) was noticed in full package excluding weed management (T₅).
       
The value of differential yield based on the yield gap per hectare was maximum in full package excluding weed management (Rs. 16684 ha^-1) followed by full package excluding RDF (Rs. 10992 ha^-1) and full package excluding insecticide application (Rs. 10019 ha^-1). While, it was least in full package excluding seed treatment (Rs. 1419 ha^-1). The similar results are close conformity with the findings of Jaybhay et al., (2021).
 
Crop output efficiency
 
The crop output efficiency in terms of partial factor productivity (PFP) and agronomic efficiency (AE) of applied nutrients to soybean crop are presented in Table 5. PFP in terms of kilogram of grain produced to the kilogram of nutrient applied (NPK) was higher with Full package (T₁) followed by full package excluding seed treatment (T₂) and Full package excluding ridge and furrow sowing (T₇). Whereas, lower PFP values under full package excluding weed management (T₅). Similarly, higher agronomic efficiency of applied nutrient (NPK) to soybean was recorded maximum in Full package (T₁), followed by full package excluding seed treatment (T₂) and full package excluding ridge and furrow sowing (T₇). Whereas, negative agronomic efficiency was observed in full package excluding weed management (T₅).
       
PFP is a measure of efficiency that includes production per unit of nutrient applied (Rose et al., (2012). Further similar results noticed by (Lohar and Hase, 2022) the integrated application of chemical fertilizer + FYM and chemical fertilizer + vermicompost was found to be highly effective to improve soil health and productivity through improved sustainability attributes like agronomic efficiency, partial factor productivity and sustainable yield index in soybean.

The long-term results concluded that, the soybean crop requires all the optimum inputs and management practices for obtaining the higher productivity. An absence/omission of the factors of production significantly affects the growth, seed yield and the economic benefits from the soybean. The weed management and recommended dose of fertilizers are the major factors contributing to soybean yield loss and attributed to maximum yield gaps compared to full package. Thus, it can be concluded that, for achieving higher productivity, profitability and agronomic efficiency of applied nutrients under full package comprising all crop management practices can be adopted over the years in Northern Transition Zone of Karnataka.

Authors are grateful to University of Agricultural Sciences, Dharwad (Karnataka) and ICAR-Indian Institute of Soybean Research, Indore for providing facilities in smooth conduct of the experiment.

All authors declared that there is no conflict of interest.