不同基因型棉花磷效率特征及其根系形态的差异

在水培条件下,以棉花磷高效品种新海18号和低效品种新陆早13号为材料,研究不同供磷条件下其生物量、磷素积累量、根系参数的差异。结果表明,在低磷与适磷时,高效基因型新海18号的磷利用效率分别为1129.2 g·g-1和262.7 g·g-1,而低效基因型新陆早13号为1090.9 g·g-1和123.0 g·g-1;新海18号地上部分磷积累量占全株磷积累量的比例分别为57.5%和48.3%,新陆早13号分别是49.9%和53.8%。低磷时,新海18号总根长、根总表面积和根总体积分别增加36.0%、145.7%和96.9%,新陆早13号总根长和根总表面积则显著下降,新海18号根系各参数均高于新陆早13号。表明高效品种具有较强的磷素利用效率和较好的根系形态参数。

Differences of Phosphorus Efficiency Characteristics and Root Morphology between Two Cotton Genotypes

To provide a basis for exploring the mechanism of high phosphorus(P) use efficiency and uptake efficiency in cotton genotypes, phosphorus efficiency characteristics and root morphology were investigated in two different cotton genotypes. Using a solution culture method, a high phosphorus efficiency genotype(Xinhai18) and a low phosphorus efficiency genotype(Xinluzao13) were evaluated for differences in dry matter weight, phosphorus accumulation and root parameters under different P application rates. The results showed that the P-efficiency of the genotype Xinhai18 was 1129.2 g·g^-1 and 262.7 g·g^-1 at low(0.01×10^-3 mol·L^-1) and high(1×10^-3 mol·L^-1) P levels, respectively, while that of the genotype XinluZao13 was 1090.9 g·g^-1 and 123.0 g·g^-1. In addition, the genotype Xinhai18 had greater ability to transfer P to the shoot than Xinluzao13. Under the two different P levels, shoot P accumulation in Xinhai18 was 57.5% and 48.3% of the whole plant, while that of Xinluzao13 was 49.9% and 39.4%. When P was insufficient, the total root length, total root surface area and total root volume of Xinhai18 increased by 36.0%, 145.7% and 96.9%, respectively, while the total root length and total root surface area of Xinluzao13 significantly decreased. Particularly when the environmental P concentration was low, Xinhai18 had a better root system than Xinluzao13. These experiments indicated that high efficiency genotypes have the capacity for greater phosphorus use efficiency and optimal root morphology parameters.