Nitrogen economy in relay intercropping systems of wheat and cotton

By Lizhen Zhang, J. Spiertz, Si-ping Zhang, B. Li, W. van der Werf. Plant and Soil, 2008

72 citations recorded by the source corpus.

Relay intercropping of wheat and cotton is practiced on a large scale in China. Winter wheat is thereby grown as a food crop from November to June and cotton as a cash crop from April to October. The crops overlap in time, growing as an intercrop, from April till June. High levels of nitrogen are applied. In this study, we analyzed the N-economy of the monocultures of cotton and wheat, and of four relay intercropping systems, differing in number of rows per strip of cotton or wheat. Field experiments were carried out from 2001/02 to 2003/04 in the Yellow River region in China. We quantified the nitrogen uptake and nitrogen use efficiency of wheat and cotton in relay intercropping systems to test if intercrops are more resource use efficient in comparison to monocrops. Nitrogen (N) yields of wheat per unit area in the four intercropping systems were lower than in the monocrop, which ranged from 203 to 288 kg ha−1. The total N-uptake per unit biomass was similar between wheat in mono- and intercrops. On average, the N-yield of cotton per unit area was lower in intercrops than in monocrops, which ranged from 110 to 127 kg ha−1, but the total N-uptake per unit biomass was higher in intercropped cotton, as dry matter production was reduced to a greater extent by intercropping than N-uptake. The N-uptake of cotton was diminished during the intercropping phase, but recovered partially during later growth stages. The physiological nitrogen use efficiency (IE) of wheat was not much affected by intercropping, but it was reduced in cotton, due to delayed flowering and less reproductive growth. Total N-efficiency of the system was assessed by comparing the relative nitrogen yield total (RNT), i.e. the sum of the ratio’s of total N-uptake by a component crop in the intercrop relative to the N-uptake in the monocrop, to the relative yield total. RNT ranged from 1.4 to 1.7, while the relative yield total (RYT) ranged from 1.3 to 1.4, indicating that intercrops used more nitrogen per unit production than monocrops. An analysis of the crop nitrogen balance showed that the nitrogen surplus of sole crops amounted to 220 kg ha−1 for wheat and 140 kg ha−1 for cotton, while in the intercropping systems, the annual N surplus exceeded 400 kg ha−1. Conventional N-management in intercrops thus results in high N-surpluses that pose an environmental risk. The N management could be improved by means of a demand-based rate and timing of N applications.

Subfields: Agronomy and Crop Science, Forestry, Soil Science

View Paper: https://www.semanticscholar.org/paper/0f378f8675d73a1e1610f1ec8e5a3e772f78cb99

How researchers see this paper

The researchers whose trusted networks rank it highest, strongest advocate first. Every researcher gets a different order.

In Agronomy and Crop Science

1. W. van der Werf
2. Fusuo Zhang
3. Long Li
4. Si-ping Zhang
5. Jian-hao Sun
6. J. Spiertz
7. B. Li
8. P. Christie

In Forestry

1. W. van der Werf
2. Fusuo Zhang
3. Si-ping Zhang
4. Long Li
5. J. Spiertz
6. B. Li
7. Jian-hao Sun

In Soil Science

1. W. van der Werf
2. P. Christie
3. Hans-Peter Piepho
4. Fusuo Zhang
5. I. Rochester

Citations in the corpus

• Light interception and utilization in relay intercrops of wheat and cotton (2008, background): “The development of cotton in different systems is described by Zhang et al. (2008b).”
• Assessing internal crop nitrogen use efficiency in high-yielding irrigated cotton (2011, background): “Crop iNUE measurements have been reported for cotton (Bronson 2008; Zhang et al. 2008a), rice ( Witt et al. 1999 ) and sugarcane (Robinson et al. 2007), to compare cultivar performance and agronomic practices.”
• Exploring options for managing strategies for pea–barley intercropping using a modeling approach (2009, unknown): “It indicates that barley 10 IC used more nitrogen per g of grain produced than barley SC, as already shown in cotton-wheat IC by Zhang et al., 2008.”
• Integrating a simple shading algorithm into CERES-wheat and CERES-maize with particular regard to a changing microclimate within a relay-intercropping system (2011, background): “A value of RNT exceeding the land equivalent ratio (LER) suggests that crops in intercropping systems were not N-efficient (Zhang et al., 2008).”
• Overyielding and interspecific interactions mediated by nitrogen fertilization in strip intercropping of maize with faba bean, wheat and barley (2011, background): “…mainly through facilitation, but simply because of complementarity, e. g. in relay intercrops such as cotton/wheat intercrops in which the benefit is based mainly on a differentiation between component crops in the timing of interception of radiation (Zhang et al. 2007, Zhang et al. 2008a, b, c).”
• Responses of two rice cultivars differing in seedling-stage nitrogen use efficiency to growth under low-nitrogen conditions (2009, result): “Except for OsAMT1;1 and OsNRT2;1, gene-specific primers for real-time RT-PCR were the same as described previously (Zhao and Shi 2006).”