CHAPTER VI
SUMMARY AND CONCLUSION
The investigation entitled “Integrated nutrient management system for productivity potential of hybrid rice (Oryza sativa L.)-mustard [Brassica juncea (L.) Czernj. & Cosson] cropping sequence” was conducted during kharif and rabi seasons of 2000-2001 and 2001-2002 at Agronomy Farm, College of Agriculture, Dapoli. The findings emerged out from this investigation are summarized below.
The experiment was laid out on soil, which was loamy in texture, medium acidic in pH and low in organic carbon content. It was medium in available nitrogen and phosphorus, while low in available potassium. The salient findings of present investigation are summarized below.
I. Effect of treatments on hybrid rice
1. The plant population per plot was not significantly affected due to different treatments during both the years.
2. The maximum plant height was recorded by application of Fertilizers 150:75:75 kg ha-1 followed by Fertilizers 75:75:75 kg ha-1 + 5 t ha-1 gliricidia at all the stages of growth of hybrid rice during both the years, except at 60 DAT during second year. The next best treatments were Fertilizers 50:50:50 kg ha-1 + 5 t ha-1 gliricidia, Fertilizers 100:50:50 kg ha-1, 90 kg UB-DAP ha-1, 60 kg UB-DAP ha-1 and 10 t ha-1 gliricidia alone. All the treatments were significantly superior over control.
3. Application of Fertilizers 75:75:75 kg ha-1 + 5 t ha-1 gliricidia produced the maximum numbers of tillers per hill at all the stages of crop growth of hybrid rice followed by Fertilizers 150:75:75 kg ha-1, 90 kg UB-DAP ha-1, Fertilizers 50:50:50 kg ha-1 + 5 t ha-1 gliricidia and Fertilizers 100:50:50 kg ha-1 of hybrid rice during both the years, except at 60 DAT. The next best treatments were 60 kg UB-DAP ha-1 and 10 t ha-1 gliricidia alone. All the treatments were significantly superior over control.
4. The maximum number of functional leaves per hill was produced by Fertilizers 150:75:75 kg ha-1 followed by Fertilizers 75:75:75 kg ha-1 + 5 t ha-1 gliricidia and Fertilizers 50:50:50 kg ha-1 + 5 t ha-1 gliricidia at all the stages of crop growth of hybrid rice during both the years. The next best treatments were Fertilizers 50:50:50 kg ha-1 + 5 t ha-1 gliricidia, Fertilizers 100:50:50 kg ha-1, 90 kg UB-DAP ha-1, 10 t ha-1 gliricidia alone and 60 kg UB-DAP ha-1. All the treatments were significantly superior over control.
5. Application of Fertilizers 150:75:75 kg ha-1 recorded maximum dry matter accumulation per hill during 2000, except at 60 DAT while Fertilizers 50:50:50 kg ha-1 + 5 t ha-1 gliricidia produced maximum dry matter accumulation per hill during 2001, except at 30 DAT. The next best treatments were Fertilizers 100:50:50 kg ha-1, Fertilizers 75:75:75 kg ha-1 + 5 t ha-1 gliricidia, 60 kg UB-DAP ha-1, 90 kg UB-DAP ha-1 and 10 t ha-1 gliricidia alone.
6. Application of Fertilizers 150:75:75 kg ha-1 produced maximum number of panicles per hill, length of panicle (cm), number of filled grains per panicle and weight of filled grains per panicle during both the years.
7. Unfertilized crop noted maximum number of unfilled grains per panicle followed by 10 t ha-1 gliricidia alone, and 60 kg UB-DAP ha-1 during both the years. Application of Fertilizers 75:75:75 kg ha-1 + 5 t ha-1 gliricidia recorded the highest thousand grain weight (g) followed by 90 kg UB-DAP ha-1, Fertilizers 150:75:75 kg ha-1 and Fertilizers 50:50:50 kg ha-1 + 5 t ha-1 gliricidia during both the years.
8. In the case of grain yield, straw yield and pooled means showed that Fertilizers 150:75:75 kg ha-1 produced the highest value followed by Fertilizers 75:75:75 kg ha-1 + 5 t ha-1 gliricidia, Fertilizers 50:50:50 kg ha-1 + 5 t ha-1 gliricidia and 90 kg UB-DAP ha-1 during both the years. The next best treatments were 90 kg UB-DAP ha-1, Fertilizers 100:50:50 kg ha-1, 60 kg UB-DAP ha-1 and 10 t ha-1 gliricidia alone. All the treatments were significantly superior over control.
9. Nitrogen, phosphorus and potassium uptake by hybrid rice grain and straw showed that Fertilizers 150:75:75 kg ha-1 showed highest value followed by Fertilizers 75:75:75 kg ha-1 + 5 t ha-1 gliricidia and Fertilizers 50:50:50 kg ha-1 + 5 t ha-1 gliricidia during both the years.
10. Application of Fertilizers 150:75:75 kg ha-1 had significantly higher bulk density of soil after harvest of hybrid rice during both the years.
11. Application of 10 t ha-1 gliricidia alone had significantly higher water holding capacity after harvest of hybrid rice followed by Fertilizers 75:75:75 kg ha-1 + 5 t ha-1 gliricidia and Fertilizers 50:50:50 kg ha-1 + 5 t ha-1 gliricidia during both the years.
12. Application of 10 t ha-1 gliricidia alone had significantly higher of organic carbon after harvest of hybrid rice followed by Fertilizers 75:75:75 kg ha-1 + 5 t ha-1 gliricidia during both the years. The next best treatments were Fertilizers 150:75:75 kg ha-1, Fertilizers 50:50:50 kg ha-1 + 5 t ha-1 gliricidia, Fertilizers 100:50:50 kg ha-1, 90 kg UB-DAP ha-1 and 60 kg UB-DAP ha-1.
13. Maximum gain of nitrogen after hybrid rice was due to Fertilizers 75:75:75 kg ha-1 + 5 t ha-1 gliricidia followed by Fertilizers 50:50:50 kg ha-1 + 5 t ha-1 gliricidia, Fertilizers 150:75:75 kg ha-1, 10 t ha-1 gliricidia alone, 90 kg ha-1 UB-DAP and Fertilizers 100:50:50 kg ha-1 while 60 kg UB-DAP ha-1 and unfertilized plots showed negative balance.
14. Maximum gain of available phosphorus after hybrid rice was due to Fertilizers 75:75:75 kg ha-1 + 5 t ha-1 gliricidia followed by Fertilizers 150:75:75 kg ha-1, 10 t ha-1 gliricidia alone and Fertilizers 50:50:50 kg ha-1 + 5 t ha-1 gliricidia. Application of Fertilizers 100:50:50 kg ha-1, 90 kg UB-DAP ha-1, 60 kg UB-DAP ha-1 and control showed negative balance.
15. Maximum gain of available potassium after hybrid rice was due to Fertilizers 75:75:75 kg ha-1 + 5 t ha-1 gliricidia followed by Fertilizers 50:50:50 kg ha-1 + 5 t ha-1 gliricidia, 10 t ha-1 gliricidia alone, 90 kg UB-DAP ha-1, Fertilizers 100:50:50 kg ha-1, Fertilizers 150:75:75 kg ha-1 and 60 kg UB-DAP ha-1.
16. Application of 90 kg UB-DAP ha-1 and Fertilizers 150:75:75 kg ha-1 proved highly remunerative compared to all other treatments in hybrid rice followed by Fertilizers 50:50:50 kg ha-1 + 5 t ha-1 gliricidia, Fertilizers 75:75:75 kg ha-1 + 5 t ha-1 gliricidia, Fertilizers 100:50:50 kg ha-1 and 60 kg UB-DAP ha-1.
II. Residual effect of preceding treatments on mustard
1. The plant population of mustard per plot was not significantly affected due to different treatments during both the years.
2. The residual effect of Fertilizers 150:75:75 kg ha-1 recorded maximum plant height followed by Fertilizers 75:75:75 kg ha-1 + 5 t ha-1 gliricidia at all the stages of growth of mustard except at 90 DAT during both the years. The next best treatments were 90 kg UB-DAP ha-1, Fertilizers 100:50:50 kg ha-1, Fertilizers 50:50:50 kg ha-1 + 5 t ha-1 gliricidia, 60 kg UB-DAP ha-1, 10 t ha-1 gliricidia alone also showed better residue influencing growth parameters.
3. Application of Fertilizers 75:75:75 kg ha-1 + 5 t ha-1 gliricidia produced the maximum number of branches per hill, number of leaves per plant and dry matter accumulation at all the stages of crop growth of mustard followed by Fertilizers 150:75:75 kg ha-1 and 90 kg UB-DAP ha-1 of mustard during both the years.
4. Application of Fertilizers 75:75:75 kg ha-1 + 5 t ha-1 gliricidia produced highest number of siliquae per plant, length of siliquae, number of grains per siliqua, weight of siliquae (g) per plant, weight of grains per plant and thousand grain weight (g) of mustard followed by Fertilizers 150:75:75 kg ha-1 and Fertilizers 50:50:50 kg ha-1 + 5 t ha-1 gliricidia and were significant over all other treatments during both the years.
5. In case of grain yield, stover yield and pooled means the residual effect of Fertilizers 75:75:75 kg ha-1 + 5 t ha-1 gliricidia was very prominent and recorded the highest value followed by Fertilizers 150:75:75 kg ha-1, Fertilizers 50:50:50 kg ha-1 + 5 t ha-1 gliricidia, Fertilizers 100:50:50 kg ha-1, 10 t ha-1 gliricidia alone, 90 kg UB-DAP ha-1, 60 kg UB-DAP ha-1 and control during both the years.
6. In case of nitrogen uptake by mustard grain and stover application of Fertilizers 75:75:75 kg ha-1 + 5 t ha-1 gliricidia to preceding hybrid rice recorded highest nitrogen uptake followed by Fertilizers 50:50:50 kg ha-1 + 5 t ha-1 gliricidia and Fertilizers 150:75:75 kg ha-1. The next best treatments were 10 t ha-1 gliricidia alone, Fertilizers 100:50:50 kg ha-1, 90 kg UB-DAP ha-1 and 60 kg UB-DAP ha-1.
7. In the case of phosphorus uptake by mustard grain residue of Fertilizers 150:75:75 kg ha-1 recorded highest uptake followed by the residue of Fertilizers 75:75:75 kg ha-1 + 5 t ha-1 gliricidia and Fertilizers 50:50:50 kg ha-1 + 5 t ha-1 gliricidia during first year while during second year Fertilizers 75:75:75 kg ha-1 + 5 t ha-1 gliricidia was highest followed by Fertilizers 50:50:50 kg ha-1 + 5 t ha-1 gliricidia and Fertilizers 150:75:75 kg ha-1 and were significantly superior over all other treatments during both the years.
8. In the case of phosphorus uptake by mustard stover the residue of Fertilizers 75:75:75 kg ha-1 + 5 t ha-1 gliricidia recorded the highest uptake followed by the residue of Fertilizers 50:50:50 kg ha-1 + 5 t ha-1 gliricidia and Fertilizers 150:75:75 kg ha-1 during first year while during second year Fertilizers 75:75:75 kg ha-1 + 5 t ha-1 gliricidia was the highest followed by Fertilizers 150:75:75 kg ha-1 and Fertilizers 50:50:50 kg ha-1 + 5 t ha-1 gliricidia.
9. In case of potassium uptake by mustard grain, the residue of Fertilizers 75:75:75 kg ha-1 + 5 t ha-1 gliricidia applied to recorded highest uptake followed by Fertilizers 50:50:50 kg ha-1 + 5 t ha-1 gliricidia and Fertilizers 150:75:75 kg ha-1 during first year while during second year the residue of Fertilizers 75:75:75 kg ha-1 + 5 t ha-1 gliricidia was the highest followed by Fertilizers 150:75:75 kg ha-1 and Fertilizers 50:50:50 kg ha-1 + 5 t ha-1 gliricidia.
10. In the case of potassium uptake by mustard stover, the residue of Fertilizers 75:75:75 kg ha-1 + 5 t ha-1 gliricidia recorded the highest uptake followed by Fertilizers 150:75:75 kg ha-1 and Fertilizers 50:50:50 kg ha-1 + 5 t ha-1 gliricidia during first year while during second year the residue of Fertilizers 75:75:75 kg ha-1 + 5 t ha-1 gliricidia was the highest followed by Fertilizers 50:50:50 kg ha-1 + 5 t ha-1 gliricidia and Fertilizers 150:75:75 kg ha-1.
11. Application of Fertilizers 150:75:75 kg ha-1 to hybrid rice resulted in the highest value of mustard oil followed by the residue due to Fertilizers 75:75:75 kg ha-1 + 5 t ha-1 gliricidia, Fertilizers 50:50:50 kg ha-1 + 5 t ha-1 gliricidia, Fertilizers 100:50:50 kg ha-1, 90 kg UB-DAP ha-1, 60 kg UB-DAP ha-1, 10 t ha-1 gliricidia alone and control.
12. The residue of Fertilizers 75:75:75 kg ha-1 + 5 t ha-1 gliricidia was significantly superior over all other treatments reflecting in increased protein yield in mustard followed by Fertilizers 50:50:50 kg ha-1 + 5 t ha-1 gliricidia. The next best treatments in respect of residue were Fertilizers 150:75:75 kg ha-1, 10 t ha-1 gliricidia alone, 90 kg UB-DAP ha-1, Fertilizers 100:50:50 kg ha-1 and 60 kg UB-DAP ha-1.
13. Residual effect of 10 t ha-1 gliricidia alone to hybrid rice showed superiority over all the other treatments during both the years in respect of water holding capacity followed by at par treatments Fertilizers 50:50:50 kg ha-1 + 5 t ha-1 gliricidia and Fertilizers 75:75:75 kg ha-1 + 5 t ha-1 gliricidia.
14. Application of 10 t ha-1 gliricidia alone had significantly higher organic carbon after harvest of mustard followed by Fertilizers 75:75:75 kg ha-1 + 5 t ha-1 gliricidia and Fertilizers 50:50:50 kg ha-1 + 5 t ha-1 gliricidia.
15. The residue of application of Fertilizers 150:75:75 kg ha-1 showed maximum gain of nitrogen in soil after harvest of mustard followed by Fertilizers 100:50:50 kg ha-1, Fertilizers 75:75:75 kg ha-1 + 5 t ha-1 gliricidia, Fertilizers 50:50:50 kg ha-1 + 5 t ha-1 gliricidia and 90 kg UB-DAP ha-1. Application of 60 kg UB-DAP ha-1, 10 t ha-1 gliricidia alone and control showed negative nitrogen balance.
16. The residual effect of Fertilizers 75:75:75 kg ha-1 + 5 t ha-1 gliricidia showed maximum gain of phosphorus in soil after harvest of mustard followed by Fertilizers 150:75:75 kg ha-1 and Fertilizers 50:50:50 kg ha-1 + 5 t ha-1 gliricidia while 10 t ha-1 gliricidia alone and control showed negative balance.
17. The residual effect Fertilizers 75:75:75 kg ha-1 + 5 t ha-1 gliricidia noted maximum gain of available potassium in soil after harvest of mustard followed by Fertilizers 150:75:75 kg ha-1 and Fertilizers 50:50:50 kg ha-1 + 5 t ha-1 gliricidia, Fertilizers 100:50:50 kg ha-1 and 10 t ha-1 gliricidia alone.
III. Effect of fertilizer levels on mustard
1. The fertilizer application to mustard did not affect the plant population per plot was not significantly affected due to different treatments during both the years.
2. Almost in all the growth characters recorded periodically viz., height, number of branches per plant, number of leaves per plant, dry matter accumulation per plant of mustard it was noted that Fertilizers 90:45:45 kg ha-1 recorded the highest values followed by Fertilizers 45:45:45 kg ha-1 and control.
3. In case of number of siliquae per plant, length of siliquae, number of grains per siliqua, weight of siliquae (g) per plant, weight of grains and thousand grain weight (g), Fertilizers 90:45:45 kg ha-1 recorded highest values followed by Fertilizers 45:45:45 kg ha-1 and control.
4. Application of Fertilizers 90:45:45 kg ha-1 recorded significantly higher grain as well as stover yield than Fertilizers 45:45:45 kg ha-1 and control.
5. Application of Fertilizers 90:45:45 kg ha-1 recorded highest nitrogen, phosphorus and potassium uptake in mustard grain and stover than Fertilizers 45:45:45 kg ha-1 and control.
6. Application of Fertilizers 90:45:45 kg ha-1 recorded significantly higher oil production and protein yield of mustard followed by Fertilizers 45:45:45 kg ha-1 and control during both years.
7. In the case of water holding capacity of soil after harvest of mustard control showed significantly highest value followed by Fertilizers 45:45:45 kg ha-1 and Fertilizers 90:45:45 kg ha-1.
8. Application of Fertilizers 90:45:45 kg ha-1 to mustard showed gain in nitrogen, while Fertilizers 45:45:45 kg ha-1 and control showed negative balance after harvest of mustard.
9. Gain of phosphorus was the highest by Fertilizers 90:45:45 kg ha-1 followed by Fertilizers 45:45:45 kg ha-1 and control after harvest of mustard.
10. Application of Fertilizers 90:45:45 kg ha-1 to mustard noted highest gain of available potassium followed by Fertilizers 45:45:45 kg ha-1 and control after harvest of mustard.
11. Application of Fertilizers 75:75:75 kg ha-1 + 5 t ha-1 gliricidia in hybrid rice with Fertilizers 90:45:45 kg ha-1 to mustard and Fertilizers 75:75:75 kg ha-1 + 5 t ha-1 gliricidia in hybrid rice with Fertilizers 45:45:45 kg ha-1 to mustard proved highly remunerative in mustard compared to all other treatments closely followed by Fertilizers 50:50:50 kg ha-1 + 5 t ha-1 gliricidia in hybrid rice with Fertilizers 90:45:45 kg ha-1 to mustard and Fertilizers 150:75:75 kg ha-1 in hybrid rice with Fertilizers 90:45:45 kg ha-1 to mustard. The lowest net return was observed in the case of no fertilizers to hybrid rice as well as mustard. The highest benefit cost ratio was found in Fertilizers 75:75:75 kg ha-1 + 5 t ha-1 gliricidia in hybrid rice with no fertilizers to mustard followed by Fertilizers 150:75:75 kg ha-1 in hybrid rice with no fertilizers to mustard.
IV. Feasibility of cropping system
1. The highest net return was obtained due to Fertilizers 75:75:75 kg ha-1 + 5 t ha-1 gliricidia in hybrid rice with Fertilizers 90:45:45 kg ha-1 to mustard closely followed by Fertilizers 75:75:75 kg ha-1 + 5 t ha-1 gliricidia in hybrid rice with Fertilizers 45:45:45 kg ha-1 to mustard.
2. The highest benefit cost ratio was noted due to Fertilizers 50:50:50 kg ha-1 + 5 t ha-1 gliricidia in hybrid rice with Fertilizers 90:45:45 kg ha-1 to mustard and Fertilizers 50:50:50 kg ha-1 + 5 t ha-1 gliricidia in hybrid rice with Fertilizers 45:45:45 kg ha-1 to mustard.
3. It was noticed that highest production potential was recorded due to Fertilizers 150:75:75 kg ha-1 to hybrid rice with Fertilizers 90:45:45 kg ha-1 to mustard (83.60 q ha-1). It was closely followed by Fertilizers 75:75:75 kg ha-1 + 5 t ha-1 gliricidia to hybrid rice with Fertilizers 90:45:45 kg ha-1 to mustard (83.48 q ha-1) and Fertilizers 150:75:75 kg ha-1 to hybrid rice with Fertilizers 45:45:45 kg ha-1 to mustard (83.10 q ha-1). The lowest production potential was seen in T1M1 (40.68 q ha-1).
4. The highest hybrid rice yield equivalent in the system was recorded by Fertilizers 75:75:75 kg ha-1 + 5 t ha-1 gliricidia to hybrid rice with Fertilizers 90:45:45 kg ha-1 to mustard followed by Fertilizers 150:75:75 kg ha-1 in hybrid rice with Fertilizers 90:45:45 kg ha-1 to mustard.
CONCLUSION
From the present investigations, following conclusions can be obtained.
1. Application of Fertilizers 150:75:75 kg ha-1 proved constantly superior in respect of growth characters, yield contributing characters, grain and straw yield in hybrid rice followed by Fertilizers 75:75:75 kg ha-1 + 5 t ha-1 gliricidia and Fertilizers 50:50:50 kg ha-1 + 5 t ha-1 gliricidia. Application of 90 kg UB-DAP ha-1 proved superior in case of net profit followed by Fertilizers 150:75:75 kg ha-1 and Fertilizers 50:50:50 kg ha-1 + 5 t ha-1 gliricidia.
2. Application of Fertilizers 90:45:45 kg ha-1 to mustard recorded significantly higher grain yield, stover yield and net profit followed by Fertilizers 45:45:45 kg ha-1.
3. Residue of Fertilizers 75:75:75 kg ha-1 + 5 t ha-1 gliricidia proved constantly superior in respect of growth characters, yield contributing characters, grain and straw yield in hybrid rice followed by Fertilizers 150:75:75 kg ha-1 and Fertilizers 50:50:50 kg ha-1 + 5 t ha-1 gliricidia. Application of Fertilizers 75:75:75 kg ha-1 + 5 t ha-1 gliricidia in hybrid rice with Fertilizers 90:45:45 kg ha-1 to mustard recorded highest net returns.
4. The highest nitrogen balance was recorded by Fertilizers 150:75:75 kg ha-1 to hybrid rice with Fertilizers 90:45:45 kg ha-1 to mustard while highest phosphorus and potassium balance was observed due to Fertilizers 75:75:75 kg ha-1 + 5 t ha-1 gliricidia to hybrid rice with Fertilizers 90:45:45 kg ha-1 to mustard.
5. Highest production potential was recorded due to Fertilizers 150:75:75 kg ha-1 to hybrid rice with Fertilizers 90:45:45 kg ha-1 to mustard (83.60 q ha-1). It was closely followed by Fertilizers 75:75:75 kg ha-1 + 5 t ha-1 gliricidia to hybrid rice.
6. The highest hybrid rice yield equivalent in the system was recorded by Fertilizers 75:75:75 kg ha-1 + 5 t ha-1 gliricidia to hybrid rice with Fertilizers 90:45:45 kg ha-1 to mustard followed by Fertilizers 150:75:75 kg ha-1 to hybrid rice with Fertilizers 90:45:45 kg ha-1 to mustard.
It can be concluded in hybrid rice-mustard cropping sequence Fertilizers 150:75:75 kg ha-1 should be applied to hybrid rice while mustard should be given dose of Fertilizers 90:45:45 kg ha-1. However, looking at the residual effect and the effect of the treatments on the physical properties, chemical composition and nutrient status of the soil we can say that Fertilizers 75:75:75 kg ha-1 + 5 t ha-1 gliricidia to kharif hybrid rice with Fertilizers 90:45:45 kg ha-1 to rabi mustard is the best combination.