Abstract: Crop growth and yield is inhibited in soda salinized land. To select suitable soil amendments for soda salinized cultivated land in Xiliaohe Plain of Inner Mongolia, three widely used soil amendments, organic silicon fertilizer (SF), humic acid fertilizer (HF) and microbial fertilizer (MF), were deployed, with no soil amendments as the control (CK). We evaluated the effects of different soil amendments on photosynthetic characteristics, dry matter accumulation and distribution of sugar beet. The results showed that soil amendments improved the photosynthetic characteristics of sugar beet. Organic silicon fertilizer showed significant regulation effects in the whole growing period, while humic acid fertilizer and microbial fertilizer showed significant effects after the rapid growing period of leaf clumps and in the early growth stage, respectively. The regulating effect of organic silicon fertilizer was stronger than that of humic acid fertilizer and microbial fertilizer. Compared with that in CK, the P_n, C_i, T_r, G_s and SPAD value of SF increased by 10.32%-21.77%, 9.08%-19.62%, 23.14%-43.35%, 17.44%-40.93% and 23.15%-28.87%; increased by 5.63%-12.33%, 2.37%-13.60%, 4.22%-31.01%, 14.65%-32.79% and 7.93%-20.06% for HF; and increased by 3.82%-10.36%, 4.51%-10.14%, 1.46%-26.54%, 6.72%-20.45% and 5.54%-18.18% for MF, respectively. Soil amendments showed a positive regulation effect on photosynthetic characteristics and facilitated dry matter accumulation, with the best performance of organic silicon fertilizer. Compared with CK, dry matter accumulation of SF, MF, and HF was increased by 12.20%-58.06%, 3.15%-13.06%, and 5.91%-20.96%, respectively. Organic silicon fertilizer showed significant effects on regulating the distribution of dry matter in different organs compared with CK, which was conducive to transport of dry matter from leaves to petioles during the rapid growing period of leaf clusters, and promoted the transport of dry matter from leaves and petioles to roots after entering the root and sugar growth period. From the rapid growth of foliage to harvest, the proportion of dry matter in leaves decreased by 4.01%-17.43%, that in petioles decreased by 7.40%-15.87%, and that in roots increased by 3.34%-5.01%. The root shoot ratio of sweet cabbage after root tuber and sugar growth period was significantly improved by 10.88%-23.34%, compared with CK. Moreover, photosynthetic characteristics, dry matter distribution ratio of different organs were significantly correlated with sugar beet yield and sugar content. Soil amendments could improve the yield and quality of sugar beet by regulating photosynthetic characteristics and improving dry matter accumulation and distribution, with the best performance of organic silicon fertilizer.

Key words: soda salinized cultivated land, soil amendment, sugar beet, photosynthetic characteristics, dry matter.