Is conservation agriculture a potential option for cereal-based sustainable farming system in the Eastern Indo-Gangetic Plains of Nepal?

Figures & data

Figure 1. Map of Nepal showing study sites in Sunsari district.

Table 1. Summary results for cereals (rice, wheat, and maize) grain yields in 2015 and 2016 in Sunsari district of Nepal

Yield (t ha^−1)	N	Treatment
		CTTPR-CTW	CTTPR-ZTW	ZTDSR-ZTW	UPTPR-ZTW
Rice	162	3.02 ± 0.05	3.2 ± 0.04	3.21 ± 0.04	3.14 ± 0.04
		CT		ZT
Wheat	153	3.15 ± 0.04		3.06 ± 0.04
		CTTPR-CTM	CTTTPR-ZTM	ZTDSR-ZTM	UPTPR-ZTM
Maize	100	6.49 ± 0.06	5.81 ± 0.06	5.86 ± 0.04	6.86 ± 0.06

CTTPR = Conventional tillage and manual transplanted rice, ZTDSR = Zero tillage direct seeded rice, UPTPR = Unpuddled mechanized or manually transplanted rice, CTW = Conventional tillage wheat, ZTW = Zero tillage wheat, CT = Conventional tillage, ZT = Zero tillage, CTM = Conventional tillage maize, and ZTM = Zero tillage maize.

Table 2. ANOVA analysis: two way factor analysis

ANOVA: Two factor without replication
Crop yield	F	P value	F crit
Rice
Rows	1.194	0.078	1.228
Columns	4.070	0.007	2.623
Wheat
Rows	0.957	0.607	1.307
Columns	1.879	0.172	3.903
Maize
Rows	1.598	0.001	1.297
Columns	88.826	0.000	2.635

Table 3. Partial economics of long term trials on rice–wheat farming system (n = 18) and rice–maize farming system (n = 6) in 2015 and 2016 in Sunsari district of Nepal

Treatment	Grain yield	Biomass	Harvest Index	Crop establishment cost	Total variable cost	Gross return	Net profit	Benefit cost ratio	Labor use (person day^−1 ha^−1)
	t ha^−1			NRs ha^−1
Rice–wheat system 2015/2016
CTTPR+CTW	8.08	15.91	0.51	43,508	102,727	232,767	130,040	2.27	100
CTTPR+ZTW	8.19	16.09	0.51	33,759	94,267	237,923	143,656	2.52	89
ZTDSR+ZTW	7.15	14.42	0.50	14,180	78,395	217,781	139,386	2.78	57
UPTPR+ZTW	8.11	15.72	0.52	18,853	80,409	237,923	157,514	2.96	71
Rice–maize system 2015/2016
CTTPR+CTM	11.75	24.13	0.49	33,598	106,030	285,540	179,510	2.69	106
CTTPR+ZTM	11.07	24.14	0.46	23,446	94,428	272,004	177,576	2.88	82
ZTDSR+ZTM	11.06	23.51	0.47	14,341	95,073	270,393	175,320	2.84	65
UPTPR+ZTM	13.1	26.54	0.49	17,242	96,039	333,479	237,440	3.47	74

Table 4. Advantages experienced with CA based practices of sampled households in 2015 and 2016 of Sunsari district (n = 60)

S.N.	Factors	ZT-wheat	ZT-maize	DS-rice
1	Optimum sowing time	58(96%)	42(70%)	52(87%)
2	Less seeds per unit area	54(90%)	54(90%)	57(95%)
3	Seed germination high	58(96%)	55(91%)	35(58%)
4	Crop establishment good	57(95%)	57(95%)	30(50%)
5	Low weed infestation	54(90%)	54(90%)	26(43%)
6	Pond time low	60(100%)	60(100%)	52(87%)
7	Increased irrigation efficiency	60(100%)	60(100%)	60(100%)
8	Increased fertilizer efficiency	57(95%)	51(85%)	47(78%)
9	Disease/Insect infestation low	33(55%)	37(61%)	26(43%)
10	Days to maturity early	54 (90)	49(81.67)	60 (100)
11	Increase in yield	41(68.34)	32(53.34)	37(61.67)

The number informs the frequency of the observed parameter and the number in bracket reflects its percentage.

Figure 2. Quantity of inputs (seed and fertilizer types) used for different cereal cultivation under conventional tillage (CT), direct seeded rice (DSR), unpuddled mechanized or manually transplanted rice (UPTPR), and zero tillage (ZT) in Sunsari district of Nepal in 2015 and 2016. In figure, CT and ZT values are expressed with mean ± standard error. Recommended rate stands for the specific amount of inputs given by the Government of Nepal for that particular location.

Figure 3. Weed management cost under CT and ZT/DSR practices for rice, maize, and wheat crop in Sunsari district of Nepal in 2015 and 2016. (NRs. 103 = $1 USD).In figure, CT and ZTR values are expressed with mean ± standard error.

Table

Wheat		Maize		Rice
YES	NO	YES	NO	YES	NO

Table

Wheat		Maize		Rice
YES	NO	YES	NO	YES	NO

Table

Wheat		Maize		Rice
YES	NO	YES	NO	YES	NO

Table

Wheat		Maize		Rice
YES	NO	YES	NO	YES	NO

Table

Wheat		Maize		Rice
YES	NO	YES	NO	YES	NO

Table

Wheat		Maize		Rice
YES	NO	YES	NO	YES	NO

Table

Wheat		Maize		Rice
YES	NO	YES	NO	YES	NO

Table

Wheat		Maize		Rice
YES	NO	YES	NO	YES	NO

Table

Wheat		Maize		Rice
YES	NO	YES	NO	YES	NO

Table

Wheat		Maize		Rice
YES	NO	YES	NO	YES	NO

Table

Wheat		Maize		Rice
YES	NO	YES	NO	YES	NO