不同花生棉花间作模式对花生生育后期生理特性及产量的影响

棉花花生间作是充分利用土地资源、缓解棉油争地矛盾的重要种植方式。在大田栽培条件下,以‘花育25’和‘聊棉19’为试验材料,设置花生和棉花种植比例分别为4∶4(H₄M₄)、6∶4(H₆M₄)和4∶2(H₄M₂)3种间作模式,以单作花生(DH)和单作棉花(DM)为对照,研究不同花生棉花间作比例对花生生育后期生理特性、产量及经济效益的影响。结果表明: 与花生单作相比,棉花花生间作促进了花生茎秆的生长,但降低了叶面积指数、主茎绿叶数和干物质积累总量,易造成花生的旺长和倒伏。不同间作模式相比,H₆M₄和H₆M₄的花生叶片叶绿素含量、净光合速率、硝酸还原酶活性和根系活力显著高于H₄M₄,并提高了超氧化物歧化酶、过氧化物酶和过氧化氢酶活性,降低了丙二醛含量。不同间作模式显著降低了花生产量和棉花产量,但经济总产值较单作棉花增加。各间作模式间相比,在H₆M₄间作模式中,花生减产幅度最小,经济总产值显著高于其他处理且土地当量比大于1,具有明显的间作优势。说明在花生棉花间作种植体系中,适当减小棉花在间作中所占的比例能够维持花生较高的光合能力,促进根系对养分的吸收,有利于延缓衰老,减弱对花生产量的影响。

Effects of different peanut-cotton intercropping modes on physiological characteristics and yield of peanut in late growth stage

Using peanut cultivar Huayu 25 and cotton cultivar Liaomian 19 as experimental material, we examined the effects of different intercropping patterns on physiological characteristics of peanut in later growth stage, yield and economic benefit, based on an experiment with five treatments, including intercropping modes of 4 rows peanut and 4 rows cotton (H₄M₄), 6 rows peanut and 4 rows cotton (H₆M₄), 4 rows peanut and 4 rows cotton (H₄M₂), sole peanut (DH) and sole cotton (DM). The results showed that intercropping mode increased the length of main stem and branches of peanut, but decreased green leaves number of main steam, leaf area index, and total dry matter accumulation. Among the intercropping modes, chlorophyll content, chlorophyll fluorescence parameters, root vigor, nitrate reductase activity under H₆M₄ and H₄M₂ were significantly higher than that under H₄M₄, as well as higher superoxide dismutase, peroxidase, catalase activity and decreased malondialdehyde content. Intercropping significantly reduced peanut and cotton yields, but enhanced the gross economic output value. The yield reduction of H₆M₄ was the lowest and the economic output was the highest among all the intercropping modes. In addition, the land equivalent ratio of H₆M₄ was greater than 1, indicating the obvious advantage of intercropping. Our results indicated that appropriate reduction of the ratio of cotton under the peanut-cotton intercropping systems could strengthen root vigor and increased nitrate reductase activity, promote nutrient absorption capacity, reduce senescence, and increase the economic output.