低磷胁迫对不同磷效率棉花干物质及养分吸收的影响

Effect of Phosphorus Stress on Dry Matter Accumulation and Nutrient Absorption of Cotton Genotypes with Different Phosphorus Efficiency

以磷高效基因型棉花新海18号(XH18)、中棉42号(CCRI-42)、新陆早19号(XLZ19)和磷低效新陆早13号(XLZ13)、新陆早17号(XLZ17)为材料,通过特殊土培系统,研究不同磷效率棉花在不同磷水平下(磷胁迫0 kg·hm-2、正常供磷150 kg·hm-2)干物质及养分吸收变化,旨在为提高养分利用效率的遗传改良提供科学依据。结果表明:低磷胁迫下,各基因型棉花生物量较适磷降低了38.6%,氮、磷、钾积累量分别降低了42.9%、44.9%和41.25%。低磷胁迫环境下,磷高效基因型棉花整株干物质及氮、磷、钾积累量分别是磷低效的1.47、1.52、1.44和1.46倍。低磷胁迫降低了棉花功能叶中SPAD值,在相同磷水平下,磷高效基因型棉花功能叶SPAD值显著高于磷低效。因此,磷高效基因型棉花在低磷胁迫环境中,能更有效地地吸收利用土壤中的养分,积累较多的生物量,从而能较好适应低磷胁迫环境。

A pot experiment was carried out to test the effects of phosphorus （P） supply levels （ phosphorus stress 0 kg .hm -2, suitable phosphorus 150 kg . hm-2） with two P genotype（ efficient XH18, CCRI-42, XLZ19; inefficient XLZ13, XLZ17）cotton on changes of dry matter and nutrient absorption, and to offer science-based fertilizer recommendations for improving efficiency of nutrient utilization of genetic improvement. The results showed that cotton biomass reduced 38.4 %, nitrogen, phosphorus and potassium accumulation decreased by 42. 9 %, 44.9 % and 41.25 % by low P stress. Efficient genotype cotton biomass and nitrogen, phosphorus, potassium accumulation were 1. 47,1.52,1.44 and 1.46 times as much as those of inefficient genotype cotton by low P stress. The content of SPAD in the leaves were significantly reduced by low P stress. The content of SPAD in the leaves of Phosphorus efficient genotype cotton was significantly higher than P-inefficient. It is concluded that P efficient genotype cotton adapted to low P stress through more effective absorbed and used nutrients in the soil, and accumulate more biomass.