Introduction
Organic manures have traditionally been the important input as sources of plant nourishment. Organic manures directly provided macro and micronutrient and indirectly facilitates in improving the physical, chemical and biological properties of soils.1 These manures, containing all the essential nutrients when applied to the preceding crop, leave the residual effect and this benefit is harvested by the succeeding crop to a great extent.2 Organic matter is the heart of fertile soil. It helps in increasing cations and anions holding capacity of soil particularly phosphorus and nitrates. Throughout the crop growth period these adsorbed nutrient ions are slowly available for the benefit of crop. Use of organic matter plays a significant role in improving the use efficiency of applied nutrients and thereby reducing the expenditure of nutrient. Organic manuring has also been reported to improve the efficiency of nitrogenous fertilizers in acidic soils.3 Buckwheat (Fagopyrum esculentum Moench) is a very old Asian crop, extensively grown throughout the globe. It is an important underutilized crop, plays a crucial role in meeting up the food security of the temperate and hilly regions of the countries in East Asia, East Europe and the Himalayan region.4 Though it is not a cereal, but the starchy seeds are generally classified among the cereal grains as of their similar usage. Ricebean (Vigna umbellata ) is a disease & insect resistant, fast growing legume crop and has the capability to produce huge amounts of healthy animal feed and high quality grain. Its cultivation is mainly confined to the Western, Northern and Eastern India and Nepal. It is broadly grown as an intercrop, predominantly of maize, and was traditionally being grown on residual moisture after rice. Ricebean can grow successfully in the large range of soils. Keeping the above facts in mind present experiment has been carried out to see the, direct and left over consequence of organics on the growth, yield and economics of buckwheat-ricebean cropping sequence.
Materials and Methods
This research trial was undertaken at the Research Farm of Uttar Banga Krishi Viswavidyalaya, Pundibari, Cooch Behar, West Bengal, India. The farm is located at 26019’86” N latitude and 89023’53” E longitude and at an elevation of 43 meters above mean sea level. The soil of the research plot was sandy loam in texture and acidic in nature having pH of 5.5. The initial organic carbon 0.639%, available nitrogen 107.59 kg ha-1, available phosphorus 15.36 kg ha-1 and available potash 71.68 kg ha-1 were recorded before buck wheat cultivation in 2012. In the first year buck wheat variety VL-7 was sown during mid January with a row and plant distance of 30 cm X 7-10 cm. Fourteen treatments were allocated in randomized complete block design and replicated thrice. Treatments comprises of T1 = Control (No manures/no fertilizers), T2 = RDF (40:20:20), T3 = Vermicompost @ 2.5 t ha-1, T4 = Vermicompost at 5 t ha-1, T5 = Mustard Cake @ 2.5 t ha-1, T6= Mustard Cake @5 t ha-1, T7 = Poultry Manure @ 2.5 t ha-1, T8 = Poultry Manure @ 5 t ha-1, T9 = F.Y.M @ 8 t ha-1, T10 = RDF +FYM @ 4 t ha-1, T11 = Vermicompost @ 2.5 t ha-1 + Mustard Cake @ 2.5 t ha-1, T12 = Vermicompost @ 2.5 t ha-1 + Mustard Cake @ 5 t ha-1, T13 = Vermicompost @ 2.5 t ha-1 + F.Y.M @ 4 t ha-1 and T14 = Vermicompost @ 2.5 t ha-1 + Mustard Cake @ 2.5 t ha-1 + Poultry Manure @ 2.5 t ha-1 + F.Y.M @ 4 t ha-1. Nutrient concentration of vermicompost, mustard cake, poultry manure and FYM were N: P: K., 1.15:0.48:0.72, 3.76:0.71:0.76, 2.71:2.31:2.10 and 0.56:0.18:0.52 respectively. After the harvest of buck wheat, ricebean (variety: RBL-6) was sown as a sequence in the end of April on residual soil fertility without disturbing the original layout of main crop. Crop management practices for buck wheat and ricebean are similar during both the year. All the organics, (well decomposed) were incorporated on dry weight basis 20 days before sowing of buck wheat. 20 days after application of organics as per treatment buck wheat were sown during 19th January and 21st January in 2012 and 2013, respectively with a seed rate of 40 kg ha-1. Improved agro techniques were followed for the crops. All the plants from individual plots were harvested at physiological maturity and data on agronomic parameters were recorded. Composite soil sample from each plot were collected after harvesting of both buck wheat and ricebean. The samples were systematically dried up in shade, pulverized, passed through 0.2 mm net and then determined for the available N, P and K. Standard statistical methods were used for comparing the treatment means. Treatments variations were analysed on the basis of F test results and critical differences were calculated at 5% level of probability. Economics was calculated based on the prevailing market price.
Results and Discussion
Stem Yield, Seed Yield and Harvest Index of Buckwheat
The seed and stem yield of buckwheat was, in general more in 2013 than in 2012 irrespective of organic sources for nutrient management (Table 1). Significantly, the highest stem (2.83 t ha-1 during 2012 and 2.97 t ha-1 during 2013) and seed yield (1.65 t ha-1 during 2012 and 1.77 t ha-1 during 2013) was observed in integrated use of vermicompost at 2.5 t ha-1 + mustard cake at 2.5 t ha-1 + poultry manure at 2.5 t ha-1 + F.Y.M at 4 t ha-1 (T14) might be due to more leaf area, dry matter accumulation, crop growth and yield attributes followed by joint application of vermicompost at 2.5 t ha-1 + mustard cake at 5 t ha-1 (T12) that was statistically equal with sole appliance of poultry manure at 5 t ha-1 (T8) during both the years of experimentation. The improvement of buckwheat yield due to different organic sources of nutrients could be attributed to the by and large advancement of crop growth, production and translocation of sufficient photosynthate. Unfertilized control (T1) recorded the lowest stem and seed yield of buck wheat during both the years of investigation. The results confirmed the experimental findings of Dietrych et al.,5, 6
It would further be seen from the said table that the highest harvest index (36.8 % and 37.3 % during 2012 and 2013, respectively) was recorded under the collective use of vermicompost at 2.5 t ha-1 + mustard cake at 2.5 t ha-1 + poultry manure at 2.5 t ha-1 + F.Y.M at 4 t ha-1 followed by joint use of vermicompost at 2.5 t ha-1 + mustard cake at 5 t ha-1 (34.1 % during 2012 and 35.2 % during 2013) which was statistically equal with sole appliance of poultry manure at 5 t ha-1 (33.3 % and 34.9 % during 2012 and 2013, respectively). Unfertilized control (T1) recorded significantly the lowest harvest index of 23.3 % and 25.3 % during 2012 and 2013, respectively.
Growth attributes and fodder yield of rice bean
Combine application of poultry manures, mustard cake and vermicompost to previous buckwheat crop significantly increased fodder yield of rice bean by 40 and 45 q ha-1, during 2012 and 2013, respectively, over 100 % RDF (Table 2) might be due to higher residual fertility for greater nutrient uptake and availability. Similar significant increases on plant height (115.6 and 117.8 cm), number of branches plant-1 (5.2 and 5.3) and number of leaves plant-1 (77.7 and 78.3) were also observed in T14 followed by joint use of vermicompost at 2.5 t ha-1 + mustard cake at 5 t ha-1 (T12) which was statistically equal with the sole application of poultry manure at 5 t ha-1 (T8) during both the years of experimentation. As soil of terai region is sandy loam with light textured, prevailing with high rainfall, causes leaching down of nutrients, that’s why combined application of all the organic manures was added in treatment T14. All the treatments comprised organic sources of plant nutrient exhibited positive left over consequence in terms of yield traits and fodder yield of rice bean than chemically treated and control plot. Chemically treated plot left insufficient amount of nutrient for the succeeding crop as most of the nutrients was utilized by the preceding crop and some portion was lost from the soil as compared to organically amended plots, as a result performance of rice bean was not at par with the organically amended plots. These results are in accordance with the findings of Iqbal et.al.,7,8 & 9
Soil Nutrient Status
Results showed that available nutrient content of soil depleted after completion of crop sequence as compared to their initial level (before buckwheat). Collective application of vermicompost at 2.5 t ha-1 + mustard cake at 2.5 t ha-1 + poultry manure at 2.5 t ha-1 + F.Y.M at 4 t ha-1 (T14) witnessed considerably highest values of available nitrogen (161.9 and 168.2 kg ha-1), phosphorus (26.2 and 34.3 kg ha-1 ) and potassium (124.0 and 127.5 kg ha-1) followed by vermicompost at 2.5 t ha-1 + mustard cake at 5 t ha-1 and mustard cake at 5 t ha-1 during both years of experimentation. Organically treated plots recorded higher values of available nitrogen, phosphorus and potassium than chemically treated plots during both the years of experimentation. The probable reason might be due to losses of nutrients from chemically treated plot. The available nitrogen was higher might be due to the fixation of atmospheric nitrogen by buckwheat. It was also found that whenever, poultry manure was applied either solely or combindly with other organic manures recorded maximum available potassium in both the years, it might be due to higher potassium content in poultry manure. The result of the present study is in agreement with the result of Singh et.al.,8, 9 & 10
Economics of buckwheat-rice bean sequence
The data on economics of buckwheat-ricebean cropping sequence in relation to organic manures and chemical fertilizers have been presented in Table 3 and 4. The economics analysis revealed that maximum gross return of ₹ 91500 and ₹ 97920 ha-1 were achieved with collective application of vermicompost at 2.5 t ha-1 + mustard cake at 2.5 t ha-1 + poultry manure at 2.5 t ha-1 + F.Y.M at 4 t ha-1 i.e. T14 closely followed by ₹81820 and ₹88300 ha-1 with vermicompost at 2.5 t ha-1 + mustard cake at 5 t ha-1 i.e. T12 during 2012 and 2013, respectively. Higher gross return was simply due to higher yield of both the crop in the sequence during both the years of experimentation. The results showed that all the organic treatments recorded higher gross returns as compared to chemically treated and control plots.
Among all treatments T8 (poultry manure at 5 t ha-1) registered the highest earnings to the tune of ₹51901 ha-1 in 2012 and ₹57941 ha-1 in 2013. This was next to T2 (₹44992 ha-1 in 2012 and ₹50351 ha-1 in 2013). The net returns were less in first year of experiment as compared to the second year simply due to lesser yield for buckwheat and ricebean in the first year. Among the organic manures mustard cake recoded comparatively lower net returns in both the years might be due to higher unit price (₹ 8.0 kg-1) of mustard cake. The highest benefit: cost ratio (2.33 and 2.59 during 2012 and 2013, respectively) was noticed in T2 (100 % RDF) followed by T10 (2.07 and 2.33 during 2012 and 2013, respectively). This was owing to the less cost incurred by these treatments. The results corroborate with the earlier findings of Panwar and Munda11 and Jaet et.al.,12
Table 1: Performances of buckwheat as influenced by organic sources of nutrient.
Treatments |
Seed yield (t ha-1) |
Stem Yield (t ha-1) |
Harvest index (%) |
||||||
2012 |
2013 |
Mean |
2012 |
2013 |
Mean |
2012 |
2013 |
Mean |
|
T1 |
0.37 |
0.48 |
0.43 |
1.20 |
1.41 |
1.31 |
23.3 |
25.3 |
24.3 |
T2 |
1.14 |
1.24 |
1.19 |
2.59 |
2.72 |
2.66 |
30.9 |
31.2 |
30.8 |
T3 |
1.00 |
1.11 |
1.06 |
2.54 |
2.68 |
2.61 |
28.2 |
29.3 |
28.7 |
T4 |
1.24 |
1.33 |
1.29 |
2.63 |
2.72 |
2.67 |
32.0 |
32.8 |
32.4 |
T5 |
1.13 |
1.23 |
1.18 |
2.60 |
2.70 |
2.65 |
30.2 |
31.2 |
30.7 |
T6 |
1.35 |
1.47 |
1.41 |
2.84 |
2.79 |
2.81 |
32.1 |
34.5 |
33.4 |
T7 |
1.12 |
1.22 |
1.17 |
2.59 |
2.69 |
2.64 |
30.1 |
31.1 |
30.6 |
T8 |
1.41 |
1.52 |
1.46 |
2.79 |
2.83 |
2.81 |
33.3 |
34.9 |
34.2 |
T9 |
1.17 |
1.26 |
1.22 |
2.57 |
2.76 |
2.66 |
31.1 |
31.3 |
31.2 |
T10 |
1.27 |
1.39 |
1.33 |
2.70 |
2.79 |
2.75 |
32.0 |
33.1 |
32.6 |
T11 |
1.39 |
1.48 |
1.43 |
2.82 |
2.79 |
2.80 |
32.1 |
34.8 |
33.7 |
T12 |
1.46 |
1.58 |
1.52 |
2.81 |
2.90 |
2.86 |
34.1 |
35.2 |
34.7 |
T13 |
1.31 |
1.42 |
1.36 |
2.76 |
2.78 |
2.77 |
32.1 |
33.7 |
32.9 |
T14 |
1.65 |
1.77 |
1.71 |
2.83 |
2.97 |
2.90 |
36.8 |
37.3 |
37.0 |
S.Em(±) |
0.08 |
0.10 |
0.09 |
0.08 |
0.10 |
0.08 |
0.94 |
0.94 |
0.94 |
CD (P=0.05) |
0.23 |
0.28 |
0.25 |
0.24 |
0.29 |
0.24 |
2.75 |
2.75 |
2.74 |
Table 2: Residual effect of organics on the performance of rice bean grown after buck wheat.
Treatments |
Plant height (cm) |
Number of branches plant-1 |
Number leaves plant-1 |
Fodder yield (t ha-1) |
||||||||
2012 |
2013 |
Mean |
2012 |
2013 |
Mean |
2012 |
2013 |
Mean |
2012 |
2013 |
Mean |
|
T1 |
98.1 |
102.5 |
100.3 |
3.3 |
3.7 |
3.5 |
29.7 |
31.0 |
30.4 |
11.00 | 11.20 | 11.10 |
T2 |
113.2 |
105.3 |
109.3 |
3.6 |
4.2 |
3.9 |
40.3 |
52.4 |
46.4 |
12.20 | 13.00 | 12.60 |
T3 |
114.2 |
102.9 |
108.5 |
3.4 |
3.8 |
3.6 |
32.7 |
34.3 |
33.5 |
11.50 | 11.40 | 11.50 |
T4 |
113.4 |
123.1 |
118.3 |
3.9 |
4.2 |
4.1 |
48.3 |
55.3 |
51.8 |
13.10 | 14.00 | 13.60 |
T5 |
114.2 |
113.6 |
113.9 |
3.5 |
4.0 |
3.7 |
38.7 |
40.0 |
39.4 |
12.00 | 12.30 | 12.20 |
T6 |
102.4 |
115.7 |
109.1 |
4.2 |
4.6 |
4.4 |
57.7 |
61.4 |
59.5 |
14.10 | 14.70 | 14.40 |
T7 |
112.7 |
114.4 |
113.5 |
3.5 |
3.9 |
3.7 |
35.7 |
37.2 |
36.4 |
11.70 | 12.00 | 11.90 |
T8 |
110.2 |
115.5 |
112.9 |
4.2 |
4.8 |
4.5 |
67.6 |
72.0 |
69.8 |
14.50 | 15.40 | 15.00 |
T9 |
114.6 |
115.3 |
114.9 |
3.9 |
4.2 |
4.1 |
45.7 |
53.6 |
49.6 |
12.30 | 13.50 | 12.90 |
T10 |
100.3 |
128.3 |
114.3 |
4.1 |
4.5 |
4.3 |
54.8 |
56.6 |
55.7 |
13.60 | 14.20 | 13.90 |
T11 |
113.5 |
114.9 |
116.7 |
4.2 |
4.8 |
4.5 |
60.7 |
66.9 |
63.8 |
14.30 | 15.00 | 14.70 |
T12 |
112.3 |
115.7 |
114.2 |
5.0 |
5.0 |
5.0 |
73.3 |
75.3 |
74.3 |
14.70 | 15.50 | 15.10 |
T13 |
115.3 |
116.5 |
114.0 |
4.2 |
4.5 |
4.3 |
55.7 |
56.7 |
56.2 |
13.70 | 14.50 | 14.10 |
T14 |
115.6 |
117.8 |
115.9 |
5.2 |
5.3 |
5.2 |
77.7 |
78.3 |
78.0 |
15.00 | 15.70 | 15.40 |
S.Em(±) |
6.75 |
7.31 |
7.01 |
0.156 |
0.15 |
0.147 |
2.76 |
2.96 |
2.82 |
0.76 | 0.84 | 0.93 |
CD (P=0.05) |
19.74 |
21.35 |
20.48 |
0.456 |
0.438 |
0.431 |
8.06 |
8.66 |
8.24 |
2.23 | 2.47 | 2.73 |
Table 3: Impact of organic sources of nutrients on soil fertility after harvesting of rice bean.
Treatments |
Available nitrogen (Kg ha-1) |
Available phosphorus (Kg ha-1) |
Available potassium (Kg ha-1) |
||||||
2012 |
2013 |
Mean |
2012 |
2013 |
Mean |
2012 |
2013 |
Mean |
|
T1 |
80.1 |
91.1 |
85.6 |
7.40 |
11.2 |
9.30 |
21.1 |
22.6 |
21.9 |
T2 |
70.2 |
75.2 |
72.7 |
10.2 |
14.3 |
12.2 |
31.2 |
31.7 |
31.5 |
T3 |
68.1 |
73.9 |
71.0 |
5.00 |
8.20 |
6.60 |
33.4 |
39.3 |
36.4 |
T4 |
75.1 |
80.1 |
77.6 |
14.2 |
19.0 |
16.6 |
66.3 |
72.8 |
69.6 |
T5 |
102.6 |
105.1 |
103.9 |
11.3 |
16.3 |
13.8 |
87.9 |
95.5 |
91.7 |
T6 |
142.9 |
156.4 |
149.7 |
22.3 |
26.4 |
24.3 |
96.2 |
101.2 |
98.7 |
T7 |
80.1 |
80.2 |
80.2 |
24.3 |
26.4 |
25.3 |
98.1 |
104.7 |
101.4 |
T8 |
120.1 |
125.0 |
122.5 |
27.1 |
29.3 |
28.2 |
103.0 |
110.3 |
106.7 |
T9 |
73.1 |
75.3 |
74.2 |
7.30 |
12.2 |
9.70 |
39.9 |
43.7 |
41.8 |
T10 |
76.3 |
77.2 |
76.7 |
15.2 |
21.3 |
18.2 |
63.0 |
72.2 |
67.6 |
T11 |
113.1 |
118.1 |
115.6 |
14.3 |
20.6 |
17.4 |
108.1 |
115.7 |
111.9 |
T12 |
159.3 |
165.1 |
162.2 |
23.4 |
26.3 |
24.8 |
114.1 |
120.6 |
117.3 |
T13 |
68.1 |
70.1 |
69.1 |
7.40 |
14.2 |
10.8 |
40.9 |
44.2 |
42.6 |
T14 |
161.9 |
168.2 |
165.1 |
26.2 |
34.3 |
30.2 |
124.0 |
127.5 |
125.7 |
S.Em(±) |
4.81 |
4.64 |
3.65 |
1.26 |
1.07 |
0.95 |
2.26 |
2.70 |
1.60 |
CD (P=0.05) |
14.04 |
13.56 |
10.68 |
3.68 |
3.13 |
2.78 |
6.61 |
7.90 |
4.69 |
Table 4: Cost of production of buckwheat and ricebean as influenced by organic sources of nutrients.
Treatments cost (₹ ha-1) |
General cost for buckwheat production (₹ ha-1) |
General cost for ricebean production (₹ ha-1) |
Total cost of production (buckwheat + ricebean) (₹ ha-1) |
|||||
Treatments |
2012 |
2013 |
2012 |
2013 |
2012 |
2013 |
2012 |
2013 |
T1 |
– |
– |
15195 |
15195 |
2104 |
2104 |
17299 |
17299 |
T2 |
2029 |
2150 |
15195 |
15195 |
2104 |
2104 |
19328 |
19449 |
T3 |
1000 |
10000 |
15195 |
15195 |
2104 |
2104 |
27299 |
27299 |
T4 |
20000 |
20000 |
15195 |
15195 |
2104 |
2104 |
37299 |
37299 |
T5 |
20000 |
20000 |
15195 |
15195 |
2104 |
2104 |
37299 |
37299 |
T6 |
40000 |
40000 |
15195 |
15195 |
2104 |
2104 |
57299 |
57299 |
T7 |
5000 |
5000 |
15195 |
15195 |
2104 |
2104 |
22299 |
22299 |
T8 |
10000 |
10000 |
15195 |
15195 |
2104 |
2104 |
27299 |
27299 |
T9 |
8000 |
8000 |
15195 |
15195 |
2104 |
2104 |
25299 |
25299 |
T10 |
6029 |
6150 |
15195 |
15195 |
2104 |
2104 |
23328 |
23449 |
T11 |
30000 |
30000 |
15195 |
15195 |
2104 |
2104 |
47299 |
47299 |
T12 |
50000 |
50000 |
15195 |
15195 |
2104 |
2104 |
67299 |
67299 |
T13 |
14000 |
14000 |
15195 |
15195 |
2104 |
2104 |
31299 |
31299 |
T14 |
39000 |
39000 |
15195 |
15195 |
2104 |
2104 |
56299 |
56299 |
Input cost of urea, single super phosphate, muriate of potash, farm yard manure, vermicompost, poultry manure and mustard cake were 6,8,15,1,4,2 and 8kg-1 respectively.
Table 5: Economics of buckwheat-ricebean sequence as influenced by organic sources of nutrients.
Treatments |
Return from buckwheat (₹ ha-1) |
Return from rice bean(₹ ha-1) |
Gross return (₹ ha-1) |
Net return (₹ ha-1) |
Benefit: Cost ratio |
|||||
2012 |
2013 |
2012 |
2013 |
2012 |
2013 |
2012 |
2013 |
2012 |
2013 |
|
T1 |
18500 |
24000 |
6600 |
6720 |
25100 |
30720 |
7801 |
13421 |
0.45 |
0.78 |
T2 |
57000 |
62000 |
7320 |
7800 |
64320 |
69800 |
44992 |
50351 |
2.33 |
2.59 |
T3 |
50000 |
55500 |
6900 |
6840 |
56900 |
62340 |
29601 |
35041 |
1.08 |
1.28 |
T4 |
62000 |
66500 |
7860 |
8400 |
69860 |
74900 |
32561 |
37601 |
0.87 |
1.01 |
T5 |
56500 |
61500 |
7200 |
7380 |
63700 |
68880 |
26401 |
31581 |
0.71 |
0.85 |
T6 |
67500 |
73500 |
8460 |
8820 |
75960 |
82320 |
18661 |
25021 |
0.33 |
0.44 |
T7 |
56000 |
61000 |
7020 |
7200 |
63020 |
68200 |
40721 |
45901 |
1.83 |
2.06 |
T8 |
70500 |
76000 |
8700 |
9240 |
79200 |
85240 |
51901 |
57941 |
1.90 |
2.12 |
T9 |
58500 |
63000 |
7380 |
8100 |
65880 |
71100 |
40581 |
45801 |
1.60 |
1.81 |
T10 |
63500 |
69500 |
8160 |
8520 |
71660 |
78020 |
48332 |
54571 |
2.07 |
2.33 |
T11 |
69500 |
74000 |
8580 |
9000 |
78080 |
83000 |
30781 |
35701 |
0.65 |
0.75 |
T12 |
73000 |
79000 |
8820 |
9300 |
81820 |
88300 |
14521 |
21001 |
0.22 |
0.31 |
T13 |
65500 |
71000 |
8220 |
8700 |
73720 |
79700 |
42421 |
48401 |
1.36 |
1.55 |
T14 |
82500 |
88500 |
9000 |
9420 |
91500 |
97920 |
35201 |
41621 |
0.63 |
0.74 |
Selling price of buck wheat and faba bean were ₹70 and 40 kg-1, respectively.
Acknowledgements
The authors are thankful to the Department of Agronomy, Uttar Banga Krishi Viswavidyalaya for the financial support and Directorate of Farm for all kinds of assistance throughout the experimentation.
Reference
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