Agriculture Reference
In-Depth Information
TABLE 6.4
Increase in Yield of Various Crops by
Rhizobium
Inoculation (RI) of Seeds
(Mg ha
−1
)
Crop
Typical Yields
Yields with RI
Yield Increase (%)
Soybean
2.04
3.35
65
Lentils
0.86
1.20
40
Black gram
0.25
0.37
49
Groundnut
0.98
1.44
47
Broad beans
0.36
0.60
67
Source:
Modified from Sherchan, D.P., and K.B. Karki. 2006. Plant
nutrient management for improving crop productivity in Nepal.
Improving plant nutrient management for better farmer liveli-
hoods, food security and environmental sustainability. In:
Proceedings of a Regional Workshop, Beijing, December 12-16,
2005. FAO RAP Publ. 2006/27, pp. 41-57.
in enhancing yields and survivability in low-fertility soils (Sherchan and Karki 2006).
Moreover, owing to the development and large-scale production of compatible bacterial
strains, it has been pointed out that high biodiversity in intensively cropped soils may
not be necessary to ensure effective nitrogen fixation (Kahindi et al. 1997).
6.4.4 M
InIMuM
and
z
ero
t
Illage
Changing tillage practices from frequent and soil-inverting cultivation to reduced
or minimum tillage systems has been demonstrated to improve soil organic matter
status, biophysical properties, and yields in the long term. The Nepal Agricultural
Research Council, with support from the Rice-Wheat Consortium, has been con-
ducting trials on no-till, direct seeding of wheat following rainy season rice crop in
the hill and plains region. This technique has the advantage of allowing early sow-
ing and reduced labor costs, and hence has proven to be economical and resource
conserving (Giri 1998). Furthermore, use of a no-till seed drill offers cost savings of
nearly 50% and higher yields by 40%-70% compared with traditional farmer methods
(Bajracharya 2001; Sherchan and Karki 2006). Tripathi et al. (2005) confirmed the
cost-effectiveness and yield benefits of the zero-till seeding technology in on-farm
trials in the Terai region. No-till seed drills allow for timely seeding of wheat, and
with the direct seeding rice technology there is considerable cost saving with rice
yield either at par or increased compared with transplanted rice.
Atreya et al. (2006) found reduced tillage systems (elimination of one or more cul-
tivation operations) in upland maize-based cropping in central Nepal to be effective
against soil and nutrient losses, while maintaining yields at par with conventional
practices. Erosion and loss of nutrients such as soil organic matter, total nitrogen,
available phosphorus, and exchangeable potassium were all significantly reduced
