Agriculture Reference
In-Depth Information
TABLE 8.9
Water Use Efficiency (WUE) of Principal Food, Vegetable, and Fruit Crops in Brazil
WUE (kg ha
−
1
mm
−
1
)
a
Crop
Scientific Name
Reference
Rice
Oryza sativa
L.
4.6
Coelho et al. (2009)
Dry bean
Phaseolus vulgaris
L.
3.9
Coelho et al. (2009)
Corn
Zea mays
L.
17.2
Coelho et al. (2009)
Wheat
Triticum aestivum
L.
9.6
Coelho et al. (2009)
Soybean
Glycine max
L. Merr.
5.7
Coelho et al. (2009)
Cotton
Gossypium hirsutum
L.
6.8
Lima et al. (1999)
Garlic
Allium sativum
L.
12.3
Lima et al. (1999)
Onion
Allium cepa
L.
40.9
Lima et al. (1999)
Potato
Solanum tuberosum
L.
38.2
Coelho et al. (2009)
Tomato
Lycopersicon esculentum
Mill.
167.6
Coelho et al. (2009)
Banana
Musa paradisiaca
L.
11.6
Coelho et al. (2009)
Water melon
Citrullus lanatus
(Thunb.) Matsum. & Nakai
29.8
Lima et al. (1999)
Cantaloupe
Cucumis melo
L.
23.1
Coelho et al. (2009)
Grape
Vitis vinifera
L.
37.7
Lima et al. (1999)
Source:
Adapted from M. A. Coelho, E. F., Coelho Filho, and A. J. P. Silva. 2009. In: Simpósio nacional sobre o uso
da água na agricultura, 3, 2009, Passo Fundo. Disponível em: http://www.upf.br/coaju/download/Eugenio.pdf.
Acesso em: 11 set. 2009; Lima, J. E. F. W., R. S. A. Ferreira, and D. Christofidis. 1999. In:
O estado das águas
no Brasil
, pp. 73-101. Brasília: MME, MMA/SRH, OMM.
a
Calculated on the basis of data of water consumed by the crops given by the authors and average yield of the irrigated
crops.
Benjamin and Nielsen (2004) and Benjamin et al. (2013) reported that plant response to dry soil
conditions can vary with the plant species and growth stage of a plant within a species. They found
that the root system of soybean was relatively unaffected by water-deficit conditions, whereas field
pea and chickpea responded to the water deficit by growing more roots deeper in the soil profile.
Campbell et al. (1995) reported that in the semiarid climate of southwestern Saskatchewan, wheat
yield, and therefore the nitrogen use efficiency response to N, was directly influenced by available
water.
Matching phenology to the water supply is an important strategy in improving WUE and conse-
quently N use efficiency. Genotypic variation in growth duration is one of the most obvious means
of matching seasonal transpiration with the water supply and thus maximizing the water transpiring
(Ludlow and Muchow, 1990). Early flowering tends to give a higher yield and greater yield stability
than later flowering, if rain does not occur during the latter half of the growing season. Moreover,
if it enables a cultivar to escape drought during the critical reproductive stages, harvest index is
improved (Ludlow and Muchow, 1990). Data presented in Table 8.10 show clearly that short-dura-
tion cultivars of upland rice were having higher grain yields compared to longer-duration cultivars
planted in the Oxisols of the central part of Brazil.
Selecting crop genotypes having a vigorous root system is also an important strategy in increas-
ing the water and nutrient uptake and consequently higher N use efficiency. Fageria et al. (2012)
studied the root system of dry bean genotypes under two P levels. The maximum root length and
root dry weight were significantly influenced by the P level as well as genotype treatments (Table
8.11). The maximum root length varied from 8.00 to 29.67 cm, with an average value of 18.86 cm
at a low P level. At a high P level, the maximum root length varied from 17.00 to 30.67 cm, with
an average value of 22.65 cm. There was a 20% increase in maximum root length at a high P level
