Growth
Plant height of green gram as recorded at different growing periods presented in Table 2, revealed a linear increase in plant height with the advancement in plant age from 15 DAS to maturity of the crop. The height of the green gram rapidly increased up to 60 DAS. During summer 2016 and summer 2017, significantly maximum plant height of green gram was recorded with treatment 100% NPK (RDF) which was found statistically at par with treatment T
12, T
16, T
2, T
6, T
7 and T
11 at maximum branching stage, flowering emergence and at maturity. Significantly highest plant heights of green gram with T
1, T
12, T
16, T
2, T
6, T
7 and T
11 was might be attributed to better growth of green gram plants due to increased availability of nitrogen and phosphorus to the plant initially through chemical fertilizers and then through nutrient release by vermicompost and FYM in the later stages in the cropping seasons .
The maximum plant height of green gram was also might be due to higher number of leaves in T
1, T
12, T
16, T
2, T
6, T
7 and T
11 which produced higher food material for the growth of the plant. The large sized leaves were responsible for the preparing more photosynthates which increased cell division and resulted in better growth of the plant. At the latter stages the growth of the green gram became slow which was might be due to the fact that plant started entering from vegetative to reproductive stage of life cycle. Similar results were also reported by
Kohler et al. (2008).
Like plant height significant changes in dry matter accumulation of green gram was also recorded at all the three stages as revealed in Table 2.
Significantly highest dry matter accumulation in green gram during summer 2016 and 2017 was recorded with treatment T
1- 100% NPK (RDF) which was found statistically at par with dry matter accumulation of green gram recorded with treatments T
12, T
16, T
2, T
6, T
7 and T
11 at all the three stages and significantly superior than rest of the treatments. The highest dry matter accumulation in these treatments was might be due to combined application of inorganic and organics to the green gram which increased the availability of major nutrients as it might has enhanced early root growth and cell multiplication leading to more absorption of nutrients from the deeper layers of soil resulting in increased dry matter accumulation. Similar results were also reported by
Borse et al., (2002) and
Mannivannan et al., (2009).
Yield
Seed yield is more important in green gram which is the result of the different combinations of many physiological processes based on the environment under which crop is grown. The synthesis, accumulation and translocation of photosynthates depend upon the source sink relationship and also on the green gram growth during early stage of crop growth. Final yield is a function of all components of source and sink operating at different phenophases during the life cycle of green gram. Seed yield and stover yield of green gram were significantly influenced by differential substitution of nutrients through organics as presented in Table 3 during summer 2016 and 2017. Significantly highest seed yield (9.56 q/ha and 10.44 q/ha) and stover yield (39.16 q/ha and 43.03 q/ha) of green gram were recorded with treatment T
1 i.e. 100% NPK (RDF) which was found statistically at par with treatments 75% NPK + 25% N through Vermicompost and FYM (1:1), 25% yearly replacement of RDF through Vermicompost and FYM (1:1) on N-basis, 75% NPK +25% N through Vermicompost, 25% yearly replacement of RDF through Vermicompost on N-basis, 75% NPK +25% N through FYM, 25% yearly replacement of RDF through FYM on N-basis and significantly superior than rest of the treatments in seed and stover yield during both the crop growing seasons. The highest seed yield of green gram was might be due to cumulative effect of yield attributes of green gram on account of increased growth which was due to higher biomass accumulation during vegetative phase leading to increased bearing capacity which ultimately increased the seed yield of green gram during summer 2016 and 2017 where as highest dry matter accumulation in these treatments results in highest stover yield in these treatments. Similar findings were also reported by of
Aslam et al., (2010) and
Meena et al. (2015).
Quality
Data regarding per cent crude protein content of green gram presented in Table 3 revealed that crude protein content in green gram were significantly influenced by differential substitution of nutrients through organics during summer 2016 and 2017. Significantly highest crude protein content in green gram was recorded with treatment 100% N through FYM which was found statistically at par with treatments 100% N through Vermicompost, 100% N through Vermicompost and FYM (1:1), 25% NPK+75% N through FYM, 25% NPK+75% N through Vermicompost and 25% NPK+75% N through Vermicompost and FYM (1:1) and significantly superior than remaining treatments. The highest per cent crude protein content in seeds of green gram with FYM and Vermicompost was might be due to more availability of nitrogen. They improved nutritional environment in the rhizosphere as well as its utilization in the plant system. The highest crude protein content in seeds of green gram was due to more nitrogen fixation by the bacteria which in turn help in better absorption and utilization of nitrogen and increased the activity of nitrate reductase that play very significant role in the synthesis of protein in seeds.
Nutrient uptake
It is evident from the data depicted in Table 4 that uptake of N, P and K in green gram during
summer 2016 and 2017 were significantly influenced by differential substitution of nutrients through organics in both the crop growing seasons. Uptake of nutrient is the function of nutrient content in crop component and dry matter yield (seed and stover). During summer 2016 significantly highest total N uptake in green gram was recorded with treatment T
12- 75% NPK +25% N through Vermicompost and FYM which was found statistically at par with total N uptake recorded with treatments T
16, T
2, T
6, T
7 and T
11 where as during summer 2017 significantly highest total N uptake in green gram was recorded with treatment T
7- 75% NPK +25% N through FYM. This might be due to the reason that nitrogen content in seed and straw of green gram were enhanced with the application of vermicompost and FYM. Increase in nutrient content in green gram is ascribed to the beneficial role of FYM, vermicompost and vermicompost and FYM (1:1) in mineralization of native as well as nutrients in soil through added fertilizers in addition of its own nutrient content which enhanced the available nutrient pool of the soil. The higher N content concentration in FYM was might be due to nitrate reductase in the synthesis of protein in grain because it is a primary component of amino acids which are building blocks of protein molecules
(Kumar et al., 2014). These results were similar to the findings of
Devidyal et al., (1999) and
Dadhich et al., (2001).
Among the different treatment during summer 2016 and 2017 significantly highest total P uptake in green gram was recorded with treatment T
11-25 % yearly replacement of RDF through FYM on N-basis where as significantly highest total K uptake in green gram during summer 2016 and 2017 was recorded with treatment T
12 -75%NPK +25% N through Vermicompost and FYM which was found statistically at par with total K uptake recorded with treatment T
16, T
2, T
6, T
7 and T
11 in total K uptake during summer 2016 and 2017. The increase in NPK uptake was might be due to improved in the physico-chemical and biological properties in the root environment wherever organics and in organics were applied together. Another reason was might be that legume crop (green gram) add large amount of organic residues through leaf fall and produced intermediate acids during organic residue decomposition and also solubilise the fixed form of N and P in soil resulting in increased uptake of N and P by the crop. These results were in conformity with the findings of
Henri et al., 2008 and
Dhakal 2016.
Economics
The data of relative economics presented in Table 5 showed that cost of cultivation of green gram was significantly influenced by differential substitution of nutrients through organics.
During summer 2016 highest cost of cultivation (Rs 19916.00/ha) was recorded with treatment 100% N through Vermicompost where as lowest cost of cultivation (Rs 14546.40/ha) was recorded with treatment 100% N through FYM. Treatment 100% N through Vermicompost was followed by treatments T
4 >T
3 >T
14> T
2=T
6 >T
15 >T
13 >T
12= T
16 >T
1 >T
7 =T
11 >T
9 >T
8 >T
10 in cost of cultivation. During summer 2017 highest cost of cultivation (Rs 19866.96/ha) of green gram was also recorded with treatment 100% N through Vermicompost followed by treatments T4 >T
3 =T
6> T
14>T
2 >T
15 >T
13 =T
16 >T
12 >T
1 >T
7 >T
8 =T
11>T
9 and T
10 with lowest cost of cultivation (Rs 14772.78/ha) with treatment 100% N through FYM. The highest cost of cultivation in treatment 100% N through Vermicompost was might be due to highest per kg cost of vermicompost associated with treatment. During summer 2016 and 2017 highest gross returns (Rs 49951.00/ha and Rs 58203.00/ha), net returns (Rs 33689.38/ha and Rs 41941.38/ha) and B:C ratio (2.07 and 2.58) were recorded with treatment T
1-100% NPK (Recommended dose of fertilizer) where as lowest gross returns (Rs 32238.25/ha and Rs 40084.25/ha) were recorded with treatment 25%NPK+75% N through FYM, lowest net returns (Rs 12709.62/ha and Rs 20602.92/ha) were recorded with treatment 25% NPK+75% N through Vermicompost and lowest B:C ratio (0.65 and 1.05) were recorded with treatment 100% N through Vermicompost during both crop growing seasons. The highest gross returns in T
1 were might be due to difference in yield of green gram between the treatments during the respective years. Difference in net returns and B:C ratio was might be due to cumulative effects of yield and price of green gram under these treatments. These results were in agreement with the findings of
Yakadri et al., (2004) and
Yadav et al., (2014).