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Fertilizer application together with other improved crop management practices
may improve the yield of dryland crops. Implementation of water and soil conserva-
tion measures, before sowing and during the crop growth, optimum plant population
and managing the insect-pests and weeds below economic threshold level might be
useful to enhance the fertilizer use efficiency in dryland crops. The fertilizer use
efficiency in dryland soils can also be enhanced through use of suitable crop culti-
vars, planting at appropriate time, fertilizer application through right method, addi-
tion of organic manures and through water and soil conservation techniques.
Planting of improved crop cultivars utilize the N more efficiently than other tradi-
tional crop cultivars. For example, Tandon ( 1980 ) reported that improved crop man-
agement practices may enhance the sorghum yield by 10 % and fertilizer use
efficiency by 3.5 %. Increase in fertilizer use efficiency has also been reported on
the Vertisols of India in several crops by Randhawa and Singh ( 1983 ). They reported
that maintenance of optimum plant population in pearl millet together with applica-
tion at 25–30 kg ha−^1 N provided the highest grain yield when the plots were kept
weed free.
In India, several on-farm studies demonstrated that the yield of castor bean,
mungbean, groundnut and maize was enhanced with the application of B, Zn and S,
and the results were more apparent when they were combined with N and P applica-
tions (Sahrawat et al. 2010 ). In China, the application of fertilizer N with organic
manures can significantly enhance the nitrogen use efficiency, crop yield and water
use efficiency (Li et al. 2009a). They further reported that combine use of N and P
fertilizer can enhance the nitrogen fertilizer recovery, nitrogen and water use effi-
ciencies, and can reduce the losses of N through volatilization. In drylands of USA
and Canada, where the crop production is limited due to low N use and less soil
water availability, use of conservation tillage, harvesting the crop stubbles tall
enough to trap snow, crop diversification, and with long term diversified crop rota-
tions involving the legumes and cover crop helped increase the overwinter water
storage, decrease the soil degradation and enhance the yield of dryland crops
(Cutforth and McConkey 1997 ).
Table 3 Impact of nitrogen and various rates of organic fertilizers on percent increase in grain
yield and precipitation use efficiency of wheat
Nitrogen rate
(kg ha−^1 ) Organic fertilizer rate Yield increase (%) Increase in PUE (%)
00 No organic fertilizer (OF) – –
50 No organic fertilizer (OF) 10.1 9.7
50 OF (19 t ha−^1 ) 34.2 34.1
50 OF (38 t ha−^1 ) 37.5 37.1
50 OF (72 t ha−^1 ) 39.3 39.1
50 OF (124 t ha−^1 ) 39.7 41.0
50 OF (248 t ha−^1 ) 41.1 41.7Source: Cheng et al. 1987
PUE precipitation use efficiency
A. Nawaz and M. Farooq