Cao Yune, Gao Yanming, Tian Yongqiang, Li Jianshe
College of Agriculture, Ningxia University, Helanshan Xilu No. 489, Yinchuan 750021, China.
College of Horticulture, China Agricultural University, Yuanmingyuan West Road No. 2, Haidian District, Beijing 100193, China.
Plants (Basel). 2022 Jun 21;11(13):1621. doi: 10.3390/plants11131621.
Due to the increase in the human population, it is necessary to seek efficient methods of increasing crop productivity and, simultaneously, sustaining the soil. One way is to grow high demand crops continuously without rotating with other crops. This practice is often accompanied by increased rates of fertilizer application that can affect efficient nitrogen (N) cycling in the plant rhizosphere soil which, in turn, affects both plant growth and environmental pollution. In the present study, twelve various cucumber soils were selected from monoculture systems presenting different cropping years and divided into two groups including soils with relatively high mineral N (HMN) content (N > 100 mg kg−1 soil) and those with a lower mineral N (LMN) content (N < 100 mg kg−1 soil). All soils were amended with the addition of compost alone or in combination with bacterial inoculation to evaluate their effects on plant growth, microbial numbers, N mineralization, and N cycling genes. In general, the HMN soils increased (p < 0.05) net N mineralization (NNM) but did not statistically (p > 0.05) affect plant biomass compared to the LMN soils; however, compost addition increased both NNM and plant biomass in the HMN soils. In addition, the HMN soils had higher fungal pathogen numbers (FPNs) but lower total microbial biomass (TMB) and bacterial numbers (BNs) compared to the LMN soils; however, compost addition decreased FPNs but increased TMB and BNs in the HMN soils (all p < 0.05). Plant biomass was positively related to TMB, BN and NNM but was negatively related to FPN (all p < 0.05). In summary, compost addition reduced the high mineral N levels’ adverse effects on the rhizosphere soil and plant growth.
由于人口增长，有必要寻求提高作物产量并同时保持土壤肥力的有效方法。一种方法是连续种植高需求作物而不与其他作物轮作。这种做法通常伴随着化肥施用量的增加，这会影响植物根际土壤中有效的氮（N）循环，进而影响植物生长和环境污染。在本研究中，从不同种植年限的单一栽培系统中选取了12种不同的黄瓜土壤，并将其分为两组，包括矿物氮（HMN）含量相对较高（N>100 mg kg−1土壤）的土壤和矿物氮（LMN）含量较低（N<100 mg kg−1土壤）的土壤。所有土壤均单独添加堆肥或与细菌接种相结合进行改良，以评估它们对植物生长、微生物数量、氮矿化和氮循环基因的影响。总体而言，与LMN土壤相比，HMN土壤增加了（p<0.05）净氮矿化（NNM），但对植物生物量没有统计学上的影响（p>0.05）；然而，添加堆肥增加了HMN土壤中的NNM和植物生物量。此外，与LMN土壤相比，HMN土壤中的真菌病原体数量（FPNs）较高，但总微生物生物量（TMB）和细菌数量（BNs）较低；然而，添加堆肥降低了HMN土壤中的FPNs，但增加了TMB和BNs（所有p<0.05）。植物生物量与TMB、BN和NNM呈正相关，但与FPN呈负相关（所有p<0.05）。总之，添加堆肥减少了高矿物氮水平对根际土壤和植物生长的不利影响。
