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Rational Phosphorus Application Facilitates the Sustainability of the Wheat/Maize/Soybean Relay Strip Intercropping System.

Chen Y, Zhou T, Zhang C, Wang K, Liu J, Lu J, Xu K - PLoS ONE (2015)

Bottom Line: With P application rates increasing, the W/M/S system decreased the PRE from 35.9% to 12.3% averaged over the three years.A rational P application rate, 72 kg P ha-1, or an appropriate soil Olsen-P level, 19.1 mg kg-1, drives the W/M/S system to maximize total grain yield while minimizing P surplus, as a result of the PRE up to 28.0%.We conclude that rational P application is an important approach for relay intercropping to produce high yield while mitigating P pollution and the rational P application-based integrated P fertilizer management is vital for sustainable intensification of agriculture in the Southwest of China.

View Article: PubMed Central - PubMed

Affiliation: Department of Plant Nutrition and Microbiology, College of Resource Science, Sichuan Agricultural University, Chengdu, China.

ABSTRACT
Wheat (Triticum aestivum L.)/maize (Zea mays L.)/soybean (Glycine max L.) relay strip intercropping (W/M/S) system is commonly used by the smallholders in the Southwest of China. However, little known is how to manage phosphorus (P) to enhance P use efficiency of the W/M/S system and to mitigate P leaching that is a major source of pollution. Field experiments were carried out in 2011, 2012, and 2013 to test the impact of five P application rates on yield and P use efficiency of the W/M/S system. The study measured grain yield, shoot P uptake, apparent P recovery efficiency (PRE) and soil P content. A linear-plateau model was used to determine the critical P rate that maximizes gains in the indexes of system productivity. The results show that increase in P application rates aggrandized shoot P uptake and crops yields at threshold rates of 70 and 71.5 kg P ha-1 respectively. With P application rates increasing, the W/M/S system decreased the PRE from 35.9% to 12.3% averaged over the three years. A rational P application rate, 72 kg P ha-1, or an appropriate soil Olsen-P level, 19.1 mg kg-1, drives the W/M/S system to maximize total grain yield while minimizing P surplus, as a result of the PRE up to 28.0%. We conclude that rational P application is an important approach for relay intercropping to produce high yield while mitigating P pollution and the rational P application-based integrated P fertilizer management is vital for sustainable intensification of agriculture in the Southwest of China.

No MeSH data available.


Diagram showing the arrangement of wheat intercropped with maize (A) and maize intercropped with soybean (B) in the field plot.
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pone.0141725.g002: Diagram showing the arrangement of wheat intercropped with maize (A) and maize intercropped with soybean (B) in the field plot.

Mentions: The field experiment was designed as a randomized block with five P treatment levels and four replicates (blocks) over three years in the same location. Every block consisted of five plots measuring 4 × 9 m2 each in which wheat (Triticum aestivum L. cv. Chuanmai No. 37), maize (Zea mays L. cv. Chuandan No. 418) and soybean (Glycine max L. cv. Gongxuan No.1) were cultivated to make the wheat/maize/soybean (W/M/S) strip relay intercropping system (S1 Fig). Each plot included two duplicates of one planting unit which was consisted of a 1-m wide wheat-soybean strip and an identical width maize strip. Each double crops strip had four rows of wheat followed by two rows of soybean after wheat was harvested, and each maize strip included two rows of maize (Fig 2). Wheat was sown in rows at spacing of 25 cm between rows. Two maize seedlings were transplanted per hole at a spacing of 40 cm between holes and 50 cm between rows. Soybean was directly sown after wheat harvested without soil tillage at spacing of 35 cm between plants and 40 cm between rows. The space was 25 cm between wheat and maize and 55 cm between maize and soybean (Fig 2). Density of intercropped wheat was about 240 plants m-2, maize 5 plants m-2, soybean 5.7 plants m-2. Wheat was sown on 11th November in 2010, 11th November in 2011, and 10th November in 2012 and harvested on 25th May in 2011, 30th May in 2012, and 11th May in 2013 respectively. Maize was transplanted on 16th April in 2011, 15th April in 2012, and 7th April in 2013 and harvested on 10th August in 2011, 6th August in 2012, and 6th August in 2013 respectively. Soybean was sown on 15th June in 2011, 14th June in 2012, and 12th June in 2013 and harvested on 27th October in 2011, 30th October in 2012, and 5th November in 2013 respectively. The coexisting periods of wheat with maize, and maize with soybean were approximately 45 days and 55 days respectively (Fig 1). With regard to soil tillage, before the experiment of annually W/M/S system i.e. before wheat sowing or after soybean harvested every year, the soil of whole experiment including both wheat-soybean strip and maize strip were identically turned over to 20 cm in depth and then smashed and plattened all by hand. During the experiment of annually W/M/S system there is no soil tillage.


Rational Phosphorus Application Facilitates the Sustainability of the Wheat/Maize/Soybean Relay Strip Intercropping System.

Chen Y, Zhou T, Zhang C, Wang K, Liu J, Lu J, Xu K - PLoS ONE (2015)

Diagram showing the arrangement of wheat intercropped with maize (A) and maize intercropped with soybean (B) in the field plot.
© Copyright Policy
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4634977&req=5

pone.0141725.g002: Diagram showing the arrangement of wheat intercropped with maize (A) and maize intercropped with soybean (B) in the field plot.
Mentions: The field experiment was designed as a randomized block with five P treatment levels and four replicates (blocks) over three years in the same location. Every block consisted of five plots measuring 4 × 9 m2 each in which wheat (Triticum aestivum L. cv. Chuanmai No. 37), maize (Zea mays L. cv. Chuandan No. 418) and soybean (Glycine max L. cv. Gongxuan No.1) were cultivated to make the wheat/maize/soybean (W/M/S) strip relay intercropping system (S1 Fig). Each plot included two duplicates of one planting unit which was consisted of a 1-m wide wheat-soybean strip and an identical width maize strip. Each double crops strip had four rows of wheat followed by two rows of soybean after wheat was harvested, and each maize strip included two rows of maize (Fig 2). Wheat was sown in rows at spacing of 25 cm between rows. Two maize seedlings were transplanted per hole at a spacing of 40 cm between holes and 50 cm between rows. Soybean was directly sown after wheat harvested without soil tillage at spacing of 35 cm between plants and 40 cm between rows. The space was 25 cm between wheat and maize and 55 cm between maize and soybean (Fig 2). Density of intercropped wheat was about 240 plants m-2, maize 5 plants m-2, soybean 5.7 plants m-2. Wheat was sown on 11th November in 2010, 11th November in 2011, and 10th November in 2012 and harvested on 25th May in 2011, 30th May in 2012, and 11th May in 2013 respectively. Maize was transplanted on 16th April in 2011, 15th April in 2012, and 7th April in 2013 and harvested on 10th August in 2011, 6th August in 2012, and 6th August in 2013 respectively. Soybean was sown on 15th June in 2011, 14th June in 2012, and 12th June in 2013 and harvested on 27th October in 2011, 30th October in 2012, and 5th November in 2013 respectively. The coexisting periods of wheat with maize, and maize with soybean were approximately 45 days and 55 days respectively (Fig 1). With regard to soil tillage, before the experiment of annually W/M/S system i.e. before wheat sowing or after soybean harvested every year, the soil of whole experiment including both wheat-soybean strip and maize strip were identically turned over to 20 cm in depth and then smashed and plattened all by hand. During the experiment of annually W/M/S system there is no soil tillage.

Bottom Line: With P application rates increasing, the W/M/S system decreased the PRE from 35.9% to 12.3% averaged over the three years.A rational P application rate, 72 kg P ha-1, or an appropriate soil Olsen-P level, 19.1 mg kg-1, drives the W/M/S system to maximize total grain yield while minimizing P surplus, as a result of the PRE up to 28.0%.We conclude that rational P application is an important approach for relay intercropping to produce high yield while mitigating P pollution and the rational P application-based integrated P fertilizer management is vital for sustainable intensification of agriculture in the Southwest of China.

View Article: PubMed Central - PubMed

Affiliation: Department of Plant Nutrition and Microbiology, College of Resource Science, Sichuan Agricultural University, Chengdu, China.

ABSTRACT
Wheat (Triticum aestivum L.)/maize (Zea mays L.)/soybean (Glycine max L.) relay strip intercropping (W/M/S) system is commonly used by the smallholders in the Southwest of China. However, little known is how to manage phosphorus (P) to enhance P use efficiency of the W/M/S system and to mitigate P leaching that is a major source of pollution. Field experiments were carried out in 2011, 2012, and 2013 to test the impact of five P application rates on yield and P use efficiency of the W/M/S system. The study measured grain yield, shoot P uptake, apparent P recovery efficiency (PRE) and soil P content. A linear-plateau model was used to determine the critical P rate that maximizes gains in the indexes of system productivity. The results show that increase in P application rates aggrandized shoot P uptake and crops yields at threshold rates of 70 and 71.5 kg P ha-1 respectively. With P application rates increasing, the W/M/S system decreased the PRE from 35.9% to 12.3% averaged over the three years. A rational P application rate, 72 kg P ha-1, or an appropriate soil Olsen-P level, 19.1 mg kg-1, drives the W/M/S system to maximize total grain yield while minimizing P surplus, as a result of the PRE up to 28.0%. We conclude that rational P application is an important approach for relay intercropping to produce high yield while mitigating P pollution and the rational P application-based integrated P fertilizer management is vital for sustainable intensification of agriculture in the Southwest of China.

No MeSH data available.