Growth parameters
The data revealed that maximum plant height at harvest was found with the application of 50% RDF + VC at 5 t ha
-1 which was statistically at par with 50% RDF + FYM at 10 t ha
-1 but was significantly higher than control treatment (Table 1). Higher plant height under 50% RDF + VC at 5 t ha
-1 might be ascribed due to involvement of zinc in auxin metabolism in combined applications of nutrients that leads to hormonal activity. Among the foliar application treatments, higher plant height at harvest was found with F3 which was statistically similar with F
2 but significantly higher than F
1. This might be due to the growth promoting substances secreted by the microbial inoculants, which in turn might have led to better crop growth attributes during foliar applications
(Singh et al., 2015).
However, at harvest maximum dry matter production was recorded with the application of 50% RDF + VC at 5 t ha
-1 which was statistically at par with 50% RDF + FYM at 10 t ha
-1 but was significantly higher than other treatments. The combined addition of these helped in better photosynthetic efficiency of crop plants which in turn increased translocation of photosynthate to sink. This remains a main tool for getting higher total dry matter accumulation. The outcomes are in similar with the results of
Nandanyiya et al., (2016).
At harvest stage higher dry matter production was observed with the application of F
3 which was statistically higher than F
2 and F
1. The reason for better growth and development in the above treatments might be due to the greater availability of nutrients in soil due to fertiliser application with biofertilizer and biofertilizer might have enhanced meristematic activity leading increased availability of major nutrients to plant from deeper layers of soil ultimately resulting in increased plant growth in terms of plant height and dry matter accumulation. The results are in close association with the findings of
Ahmed et al. (2017) in chickpea.
Maximum leaf area index at harvest was recorded with the application of 50% RDF + VC at 5 t ha
-1 which was statistically at par with 50% RDF + FYM at 10 t ha
-1 and 75% RDF + VC at 5 t ha
-1 but was significantly higher than other treatments. Higher leaf area index under 50% RDF + VC at 5 t ha
-1 might be ascribed to balanced use of fertilizers that resulted in better formation of photosynthates which promotes the metabolic activities, number of functional leaves per plant increased ultimately led to enhanced leaf area index.
Among the nano fertilizer treatments, higher leaf area index at harvest was found with F
3 which was significantly higher than F
2 and F
1. This may be due to better nutrient uptake and availability which increased plant height and higher number of functional leaves per plant that enhanced leaf area index
(Jaipaul et al., 2011 and
Abiyot Abeje et al., 2022).
However, at 60 DAS to harvest, maximum crop growth rate was found with the application of 50% RDF + VC at 5 t ha
-1 which was statistically at par with 50% RDF + FYM at 10 t ha
-1 and significantly higher than 75% RDF + VC at 5 t ha
-1, 75% RDF + FYM at 5 t ha
-1 and control. Increase in crop growth rate might be due to balanced nutrients attributed to better nutritional environment for plant growth at active vegetative stages because of enhancements in cell multiplications, cell elongation and cell expression in plant body which ultimately increased the CGR
(Verma et al., 2019 and
Jitendra et al., 2023). At 60 DAS to harvest stage higher crop growth rate was observed with the application of F
3 which was significantly superior over all other treatments. Application of nano emulsion biofertilizer increases the crop growth rate and facilitates the solubilization and mobilization of phosphorus and nitrogen and increases nutrient uptake that attributed more biomass accumulation at active vegetative stages which increased the crop growth rate
(Egamberdieva et al., 2015).
Maximum chlorophyll (SPAD value) at peak flowering stage was found with the application of 50% RDF + VC at 5 t ha
-1 which was statistically higher than other treatments. Higher chlorophyll (SPAD value) under 50% RDF + VC at 5 t ha
-1 might be due to the observed behaviour linked to the fact that fertilizers as well as mix of organic and chemical fertilizers offer a larger amount of residual nitrogen to plants. This excess nitrogen content most likely caused a rise in chlorophyll levels which are important components of photo synthetically active pigments that give leaves their green hue. At peak flowering stage higher chlorophyll (SPAD value) was found with the application of F
3 which was significantly superior over all other treatments. It might be due to the increased nutrient availability and uptake by chickpea through colonization in the rhizosphere and thus increases the chlorophyll (SPAD value), because nutrients availability is crucially important in increasing chlorophyll biosynthesis. These results are in good agreement with
Abhirami et al., (2023).
Yield and yield attributes
Yield attributes is a resultant effect of the vegetative development of crop that determines the yield. Yield attributes, viz., number of pods/plant is significantly affected by soil application of nutrients except number of seeds/pod and 100-seed weight (Table 2). However, at harvest stage maximum number of pods/plant were recorded with 50% RDF + VC at 5 t ha
-1 which was statistically at par with 50% RDF + FYM at 10 t ha
-1 but significantly higher than 75% RDF + VC at 5 t ha
-1, 75% RDF + FYM at 5 t ha
-1 and 100% RDF. The increase in number of pods/plant is due to the application of balanced fertilizers that lead to increased flowers and pollen grain viability and thereby increased number of pods/plant
(Munazza et al., 2021).
Nano emulsion biofertilizer have significantly influenced the yield attributes,
viz., number of pods/plant. Maximum number of pods/plant at harvest stage was found with F
3 which was significantly higher than other treatments, respectively. It might be due to the fact that foliar applications with nano emulsion biofertilizer enhanced the floral buds, prevented the floral shedding and activate the biochemical functions in plants, enzyme activation, photosynthesis, cell division and translocation of photosynthates from source to sink that resulted in higher number of pods plant
-1. Similar results were also reported by
Gurrala Suresh et al., (2024).
Seed and stover yield were influenced significantly by different soil and foliar applications of nutrients, except harvest index. Higher seed and stover yield were found with the application of 50% RDF + VC at 5 t ha
-1 which was statistically at par with 50% RDF + FYM at 10 t ha
-1 and significantly higher than other treatments. The increase in seed and stover yield is due to adequate nutrients supply which helps in better translocation of photosynthates from source to sink that results in increased plant growth and yield attributes which ultimately resulted in higher crop yield as documented by
Singh et al., (2016) and
Singh et al., (2023).
However nano emulsion biofertilizer treatment has significantly influenced the seed and stover yield. Among the different nano fertilizer treatments, higher seed and stover yield were observed with F
3 which was statistically similar with F
2 but significantly higher than F
1. This might be due to the well-recognized availability of plant growth promoting bacteria that might have enhanced the plant growth activities
viz., nutrient solubilization, production of secondary metabolites, enhanced nitrogen fixation and production of plant growth hormones
(Ali et al., 2017).
The interaction effect of different soil and foliar fertilizer applications on seed yield was significant (Table 3). However, 50% RDF + VC at 5 t ha
-1 along with Nano emulsion biofertilizer resulted in the highest seed yield (1847 kg ha
-1) which was statistically at par with 50% RDF + FYM at 10 t ha
-1 along with Nano emulsion biofertilizer but significantly higher than 75% RDF + VC at 5 t ha
-1 (S
3) along with Nano emulsion biofertilizer. The release of growth-promoting chemicals generated by microbial inoculants may have contributed to the combined application’s likely better results by improving root establishment, water and nutrient uptake and transpiration
(Verma et al., 2019).
Nutrient uptake
Nitrogen (N), phosphorus(P) and potassium (K) uptake was influenced significantly by soil and foliar application of nutrients. The interaction effect of different soil application levels and foliar applications on nutrient uptake was found significant (Table 4). However, Nano emulsion biofertilizer along with 50% RDF + VC at 5 t ha
-1 recorded with the highest N, P and K uptake which was statistically at par with Nano emulsion biofertilizer along with 50% RDF + FYM at 5 t ha
-1 but significantly higher than Nano urea and Nano DAP combined treatments. The higher nutrient uptake might be ascribed due to balanced amount of fertilizers that offers a natural solution enriched with crucial nutrients, humic acids, plant growth-regulating hormones and enzymes, which positively influence plant nutrition, photosynthesis and the nutrient uptake.
Higher N, P and K uptake were observed with the application of F
3, which was significantly higher than other treatments. This may be due to the fact that microorganisms favoured nitrogen fixation, solubilization, mobilization of plant nutrients and reduced the need for chemical fertilizers and enhanced the nutrient availability and uptake to plants, which is similar to the findings reported by
Gulen and Nizamettin (2021) and
Singh et al., (2024).