Effects of soil conditioner on soil salinity,pH of saline-alkali soil,and yield of Kirin watermelon
The effects of soil conditioner (0,300,600 kg·hm-2) on soil salt content and pH value,as well as the growth,yield and quality of Kirin watermelon 'Meidu ' were measured through field experiments in Yin-chuan,Ningxia in 2022.The goal was to provide a theoretical basis and technical support for improving saline-alka-line soils and achieving high-yield,high-efficiency production of Kirin watermelon.Results showed that soil salt content and pH value decreased with the increase of application rate of soil conditioner.Compared with no soil con-ditioner application ( CK),the soil salinity in 0~20 cm of the treatments with conditioner application rate of 300 kg·hm-2 and 600 kg·hm-2 decreased by 23.20% and 27.99%,respectively,and soil pH decreased by 1.87% and 3.62%,respectively.Soil conditioner treatments increased soil nitrate nitrogen,ammonium nitrogen,available phosphorus contents and watermelon main vine length,stem thickness,leaf area,leaf SPAD value and photosyn-thesis at different extent,and the 600 kg·hm-2 treatment had a better promotion effect.Compared with CK,the fruit yield of Kirin watermelon increased by 6.72% and 10.97% with 300 kg·hm-2 and 600 kg·hm-2 of soil con-ditioner,respectively.The peel hardness and fruit diametar and vertical diameter of watermelon increased with the application of soil conditioner,and the differences between the 600 kg·hm-2 and CK treatments were significant ( P<0.05) .Meanwhile,the application of 600 kg·hm-2 significantly increased soluble solids and lycopene content of watermelon hearts,which were 5.66% and 3.54% higher than that of the CK treatment,respectively.In conclu-sion,the soil conditioner significantly reduced the salt content and pH value of saline-alkali soil,increased the soil nutrient contents,and simultaneously promoted the growth of Kirin watermelon,improving both its yield and quality.The recommended application rate of soil conditioner was 600 kg·hm-2 in the experiment.