向日葵和马铃薯间作模式的生产力及水分利用

本研究通过对不同间作模式中作物水分吸收和利用的分析比较,探讨间作提高产量的机理,提出适合当地生态环境的最优间作模式,并提供一定理论依据。于2009年和2010年在内蒙古武川进行了大田试验,研究马铃薯/向日葵不同间作模式水分吸收和利用,结果表明,马铃薯/向日葵2种间作模式:2行马铃薯:2行向日葵(2P:2S)和4行马铃薯:4行向日葵(4P:4S)的土地当量比LER为1.2～1.3,都具有较强的间作产量优势。其中,4P:4S间作体系2年平均的LER为1.26,间作优势最大。4P:4S间作马铃薯的农田蒸散量ET与单作马铃薯的ET相比差异不显著。单作向日葵和间作向日葵的农田蒸散量ET无显著差异。虽然,2P:2S间作模式和4P:4S间作模式的马铃薯水分利用效率WUE比单作分别降低了81%和66%,但2种间作模式下向日葵的水分利用效率与单作相当。因此,在马铃薯和向日葵间作模式中,整体的水分利用效率提高了,水分当量比WER在1.2～1.3,其中4P:4S间作系统的水分当量比2a均为1.3,说明该体系具有显著的水分利用优势。综合分析认为,马铃薯/向日葵间作特别是4P:4S间作模式有利于提高土地生产力和农田水分的利用效率,在可持续雨养农业发展中具有很好的应用价值。

Productivity and water use in sunflower intercropped with potato

In this paper, we analyzed water uptake and water use of plant under different intercroppings, probed the mechanism that intercropping can increase yield, propounded optimal intercropping model that suited for the local ecological environment, and provided some theoretical basis. Field experiments were carried out from 2009 to 2010 in Wuchuang, Inner Mongolia, and water uptake and water use under different potato/sunflower intercroppings was studied. Results showed that the two potato/sunflower intercrops had yield advantage. The land equivalent ratios (LER) of two rows potato and 2 rows sunflower (2P:2S) and four rows potato and four rows sunflower (4P:4S) intercropping systems ranged from 1.2 to 1.3. That for 4P:2S was highest (1.26), had a significant advantage in land productivity. The actual evapotranspiration (ET) of potato between intercropping and sole systems was not significantly different. The same results were existed for sunflower. Comparison with water use efficiency (WUE) of sole potato, although the WUE of intercropped potato in 2P:2S intercrop and 4P:4S intercrop decreased 81% and 66%, but the WUEs of intercropped sunflower in two intercrops were as the same as that of the monoculture, therefore, the WUEs of the intercropping systems at field level were increased. Water use equivalent ratios (WER) of two intercrops ranged from 1.2 to 1.3, especially, in 4P:4S intercropping system were 1.3, indicated that this intercropping system had highest advantage in water use. It is concluded that the potato/sunflower intercrops, especially for 4P:4S intercrop, improve the land productivity and water use efficiency, and could be applied in sustainable development in the region of rainfed agricutlure.