Effect of treatments on sequence duration and employment generation
Table 1 indicates that cotton - summer pearlmillet cropping system required 337 days to complete the cropping sequence with 92.33% land use efficiency which was the maximum as compared to other cropping systems which indicates that land was continue cultivated. Only for 28 days in year land was on rest because cotton crop was followed by pearlmillet crop immediately after harvesting of cotton.
Among all treatments, treatment C
3R
0F
2 (Greengram - mustard - summer pearlmillet + no residue incorporation + 75% RDN through inorganic fertilizer + 25% RDN through FYM) generated highest human labours (265 human labours). This might be due to three crops in sequence which required more labours for completing all operations.
Performance of cropping systems
Prevailing market price become an additional important factor in choosing the components of cropping systems and so sequence crop yields were converted into pearlmillet equivalent yield (Table 2 and Fig 1). Pearlmillet equivalent yield was significantly higher (15,241 kg/ha) with cotton - summer pearlmillet cropping system than rest of the treatment but it remained at par with greengram - mustard - summer pearlmillet. The magnitude of increase in pearlmillet equivalent yield in cotton - summer pearlmillet cropping system was to the tune of 8%, 44% and 57% over greengram - mustard - summer pearlmillet, greengram +
kharif castor (relay) and greengram -
rabi castor, respectively. Higher pearlmillet equivalent yield secured in cotton - summer pearlmillet cropping system might be due to higher biomass production of cotton crop during
kharif as well as summer pearlmillet gave higher yields when it is grown after cotton in sequence. These finding are in conformity with those reported by SDAU (2010) and SDAU (2011). They reported that cotton - summer pearlmillet was remunerative cropping system as compared to others.
System productivity in terms of pearlmillet equivalent yield was the highest in cotton - summer pearlmillet cropping system (41.76 kg/ha/day) as depicted in Table 2. The magnitude of increase in system productivity in cotton - summer pearlmillet cropping system was to the extent of 8%, 44% and 57% compared to greengram - mustard - summer pearlmillet, greengram +
kharif castor (relay) and greengram -
rabi castor. The system productivity was the highest in this treatment as a result of the higher quantity of yield produced. These findings are in close conformity with those reported by SDAU (2010), SDAU (2011) and SDAU (2013).
System profitability is a function of the quantity of yield produced, the cost of cultivation and the prevailing market price of the produce to obtain an overall net profit per day. System profitability among the treatments, in terms of net realization to the days in a year was significantly the highest in cotton - summer pearlmillet cropping system (₹380/ha/day) as indicted in Table 2. Cotton - summer pearlmillet cropping system secured 19%, 52% and 81% higher profitability as compared to greengram - mustard - summer pearlmillet, greengram +
kharif castor (relay) and greengram -
rabi castor. Cotton and summer pearlmillet in the system gave an economic advantage in terms of the quantity of yield produced which resulted higher amount of net realization. These results lend support of the findings reported by
SDAU (2010),
SDAU (2011) and
SDAU (2013).
The cropping system greengram +
kharif castor (relay) proved its superiority by recording significantly the lowest total number of weeds per m
2 and total weed dry weight of sequence. This might be due to dense crop canopy of greengram and
kharif castor relay system restricted the weed growth by smothering effect which was also responsible for lower dry weight of weeds. In addition to this, sowing of relay castor required clean area between greengram rows reduced the weed infestation in greengram at harvest as castor crop was sown just before harvesting of greengram.
Effect of residue incorporation
Pearlmillet equivalent yield was significantly affected by residue incorporation treatments (Table 2 and Fig 1). Among the treatments in the experiment, the highest pearlmillet equivalent yield (13,306 kg/ha) was under residue incorporation which was 16% higher over no residue incorporation. Higher pearlmillet equivalent yield secured in treatment might be due to residue incorporation increased organic matter in soil and availability of nutrients to crops which resulted higher biomass production. These finding are in conformity with those reported by
Kaleeswari et al., (2007), Singh et al., (2010) and
SDAU (2011). Kaleeswari
et al., (2007) observed that incorporation of crop residue in soil recorded higher grain yield of maize and maize grain equivalent yield.
Singh et al., 2010 reported that incorporation of crop residues has improved the mean rice equivalent yields of system by 7.86% as compared to their removal.
SDAU (2011) observed that residue incorporation significantly increased pearlmillet equivalent yield.
System productivity among the treatments, in terms of pearlmillet equivalent yield per day was highest in residues incorporation (36.46 kg/ha/day) as depicted in Table 2. The magnitude of increase in system productivity in residue incorporation was to the extent of 16% as compared to no residue incorporation. The system productivity was the highest in the residue incorporation as a result of the higher quantity of yield produced by application of residue in soil which increased organic carbon and helps to improve soil physico chemical properties.
From the evidence (Table 2) it seems that system profitability in terms of net realization per day was significantly the highest in residue incorporation (₹322/ha/ day). Residue incorporation secured 25% higher profitability as compared to no residue incorporation. Higher amount of net realization obtained in this treatment possibly the main reason for higher profitability.
Residue incorporation treatment rank first by recording significantly the lowest total number of weeds per m
2 of sequence. This might be due to the organic acid produced by residues might have become barrier for germination of weeds. Moreover while incorporation of residue the upper layer of weed seeds placed at depth which is also responsible for lower number of weeds. Total weeds dry weight of sequence was found to be non-significant.
Effect of fertilizer dose
Among the treatments, the highest pearlmillet equivalent yield (12,824 kg/ha) was observed under 75% RDN through inorganic fertilizer + 25% RDN through FYM which was 7% higher over 100% RDN through inorganic fertilizer (Table 2 and Fig 1). Higher pearlmillet equivalent yield secured in this treatment might be due to application of FYM which increased organic matter in soil and availability of nutrients to crops which resulted higher biomass production. These finding are in conformity with those reported by
Kaleeswari et al., 2007, Patil et al., (2007) and
Jat et al., (2011). Patil et al., (2007) recorded that application of recommended package of practice (½ N through urea + ½ N through FYM) registered significantly higher maize equivalent yield as compared to farmers practice except fertilizer + RDF.
Jat et al., (2011) found that application of FYM 5 t/ha + 50% RDF to groundnut recorded significantly higher groundnut equivalent yield.
System productivity among the treatments, in terms of pearlmillet equivalent yield per day was the highest in treatment 75% RDN through inorganic fertilizer + 25% RDN through FYM (35.13 kg/ha/day) as depicted in Table 2. The magnitude of increase in system productivity in this treatment was to the extent of 7% as compared to 100% RDN through inorganic fertilizer. The system productivity was the highest in this treatment as a result of the higher quantity of yield produced by application of FYM which increased organic matter in soil helps to improve soil physico chemical properties. These results lend support of the findings reported by
Jat et al., (2011). They observed that use of organic and inorganic nutrients (FYM 5 t/ha + 50% RDF) to
kharif groundnut recorded significantly higher total system productivity in term of groundnut equivalent yield over the use of inorganic nutrients.
From the evidence (Table 2) it seems that system profitability among the treatments in terms of net return per day was significantly the highest under 75% RDN through inorganic fertilizer + 25% RDN through FYM (₹297/ha/day). This treatment secured 5% higher profitability as compared to 100% RDN through inorganic fertilizer. Higher amount of net realization obtained in this treatment possibly the main reason for higher profitability.
Interaction effect
Weed counts
Interaction effect of cropping systems and fertilizer dose (C x F) and residue incorporation and fertilizer dose (R x F) as well as cropping systems, residue incorporation and fertilizer dose (C x R x F) were found to be significant with respect to weed count.
From the interaction data (Table 2.1), it is revealed that treatment combination C
2F
1 (Greengram +
kharif castor (relay) + 100% RDN through inorganic fertilizer) recorded significantly the lowest total weeds (45.3) but was at par with combination C
4F
1. This might be due to the organic acid produced by residues might make a barrier for germination of weeds. Moreover while incorporation of residue, the upper layer of weed seeds placed at depth which is also responsible for lower number of weeds. Beside this, chemical fertilizer does not contain weed seeds which could be responsible for higher total weeds.
Residue incorporation + 100% RDN through inorganic fertilizer (R
1F
1) recorded significantly the lowest total number of weeds (51.0).
The treatment combination C
2R
1F
1 (Greengram +
kharif castor (relay) + residue incorporation + 75% RDN through inorganic fertilizer + 25% RDN through FYM) recorded significantly lower total number of weeds which was at par with C
4R
1F
1 and C
2R
0F
1. Lower number of weeds in this combination because greengram and
kharif castor relay system suppress growth of weed by their dense crop canopy imparted smothering effect as well as residues incorporation reduced germination of weeds as seeds of weed placed deep during incorporation. Beside this, chemical fertilizer does not contain weed seeds which could be responsible for higher total weeds.
Weed dry matter
Combined effect of cropping systems and fertilizer dose (C x F) on total of weeds dry weight was found to be significant with respect to weed dry matter.
It is revealed (Table 2.2) that lower weed dry weight (86.5 g/m
2) was recorded with treatment combination C
2F
1 (Greengram +
kharif castor (relay) + 100% RDN through inorganic fertilizer) but it was at par with C
4F
1. Lower total number of weeds in this combination was main reason for low weed dry weight. This is true because the total number of weeds were less in this treatment combination.