生物炭对不同连作年限棉田棉花光合特性的影响

摘要

Hybrid cotton C111 was chosen as experimental material. The cotton fields continuous cropping for 2, 6, 11 and 14 years were selected, the soil were treated by the biochar in 0(C1),20(C2) and 40 t/hm2 (C3). Photosynthetic gas exchange parameters, photosynthetic physiological parameters, chlorophyll content and yield of cotton were investigated in seeding stage (D1), bud stage (D2), flowering and boll-setting period (D3) and boll opening stage (D4). The results showed that net photosynthetic rate (Pn), gs,AQY, CE, RUBPmax, chlorophyll content and yield of cotton were significantly increased in C2 and C3 treatments compared with C1 treatment (P﹤0.05), and C3 treatment was also higher than C2 (P﹤0.05). Biochar treatments in different continuous cropping years were not significantly different compared with the control in Ci, it was considered that the reduction in Pn under long continuous cropping years was mainly caused by non-stomatal restriction. Transpiration rate (E) could be reduced by biochar treatment, however, it was non-significant (P>0.05).%以品种C111为试材,选择2、6、11和14年4种连作年限的土壤,采用0(C1)、20(C2)和40 t/hm2(C3)共3个浓度生物炭处理,在苗期(D1)、蕾期(D2)、花铃期(D3)和吐絮期(D4)测定了不同处理对棉花叶片光合气体交换参数、光合生理参数、叶绿素含量和产量的影响。结果表明,与C1处理相比,C2和C3处理显著提高了棉花叶片的净光合速率(Pn)、气孔导度(gs)、光合能力(Pm)、表观量子效率(AQY)、羧化效率(CE)、RUBP最大再生速率(RUBPmax)、叶绿素含量和子棉产量(P﹤0.05),并且40 t/hm-2生物炭处理(C3)显著高于20 t/hm2(C2)处理；不同连作年限生物炭处理胞间CO2浓度(Ci)与对照比差异不显著(P>0.05),连作年限长时光合速率下降的主要原因是非气孔因素；添加生物炭处理可以降低蒸腾速率(E),但差异不显著。