不同碳氮比条件下鸡粪和椰糠高温堆肥腐熟过程研究

用鸡粪和椰糠作为基本堆肥原料进行高温堆肥试验,通过控制鸡粪和椰糠的添加量调节堆体初始C/N比,研究其对堆肥过程中堆体温度、p H值、C/N比及养分全量等理化指标的影响,探究鸡粪和椰糠高温堆肥的最适C/N比。结果表明,当C/N比为25时,堆体达到最高温度(57℃),且高温持续时间最长(14 d)。堆肥过程中各处理有机质、全碳、C/N比均呈下降趋势,p H值均呈先上升后下降趋势,全氮和种子发芽指数呈上升趋势。堆肥结束后,堆体F1(初始C/N比为20)、F2(初始C/N比为25)和F3(初始C/N比为30)的C/N比分别为11.13、11.19和10.24,总养分含量w分别为7.94%、8.63%和8.29%,种子发芽指数分别为77.90%、100.65%和93.30%。     

Effects of bio-organic fertilizers on pineapple heart rot and bacterial community structure北大核心CSCD

Heart rot is a common soil-borne disease in the pineapple industry, but the situation can be alleviated by the application of bio-fertilizers with beneficial microbiomes. Clarifying the controlling mechanism of bio-organic fertilizer on the high incidence of heart rot is critical in monocultural pineapple cropping patterns. In our study, the soil of continuous cropping pineapple orchards was collected. Three types of carriers (rapeseed cake, peat soil, and coconut bran), biocontrol strains (Bacillus subtilis HL2 and Streptomyces strain HL3), and organic fertilizer (YJ) were composted into different bio-fertilizers (KC, KN, KY, LC, LN, and LY), which were used in pot experiments. The controlling effect of the bio-fertilizer was determined based on the response of pineapple heart rot and bacterial communities to different fertilizing methods. Our results revealed that the incidence of heart rot in bio-fertilizer KC was the lowest, which decreased by 20% and 13.3%, respectively, compared to HF (chemical fertilizer, 16-16-16) and YJ (organic fertilizer). The richness and diversity of soil bacterial communities in all biofertilized treatments (KC, KN, KY, LC, LN, and LY) were significantly higher than those in HF. However, the α-diversity indices of the bio-fertilizers (KC, KN, and KY) were higher than those of LC, LN, and LY, and the bacterial community composition was significantly different. The bacteria GP4, GP6, Bacillus, and Azohydromonas were enriched in KC, KN, and KY, while the relative abundance of Streptomyces increased significantly in LC, LN, and LY. Furthermore, Spearman correlation analysis showed that the relative abundance of these bacterial groups was significantly negatively correlated with the incidence of pineapple heart rot. In summary, the application of bio-organic fertilizers can decrease the incidence of pineapple heart rot by altering the soil bacterial community structure and stimulating beneficial soil microorganisms, which is important for reconstructing the ecological balance in continuous pineapple orchards. © 2022 Authors. All rights reserved.     

香蕉茎秆、桉树皮和猪粪不同配比堆肥研究

通过固定猪粪添加量,依次增加桉树皮添加量,减少香蕉茎秆添加量,研究了桉树皮、香蕉茎秆和猪粪不同配比,不同C/N比值等对堆肥温度、pH值、微生物数量以及种子发芽率等堆肥发酵指标的影响,并用腐熟的有机肥进行香蕉幼苗盆栽试验。结果表明,堆肥材料C/N比值为25.24和27.01的处理堆肥温度较高,均达到56℃以上,持续高温时间分别为10和11 d,堆肥中各养分含量相对较高,达到NY 525—2012《有机肥料》标准。盆栽试验也表明,利用堆肥材料C/N比值为25.24和27.01的堆肥配制的有机肥对盆栽香蕉幼苗有一定的促生效果。     

轮作联用生物有机肥促进香蕉生长

为促进连作蕉园恢复香蕉高效栽培,采集连作蕉园土壤,利用盆栽实验研究连作蕉园土壤轮作菠萝与玉米联合生物有机肥施用,对连作土壤理化性质、可培养微生物和总细菌、总真菌数量及下茬香蕉生长的影响.结果显示:较之香蕉连作对照,连作土壤轮作菠萝或玉米后再植香蕉,其叶片数、株高、茎粗、叶面积、地下部鲜重和地上部鲜重均有不同程度提高,其中株高和叶面积显著高于连作对照处理,轮作菠萝处理促生效果优于轮作玉米处理;联合生物有机肥施用后,进一步促进了香蕉的生长;菠萝和玉米轮作后均对土壤pH有一定影响,菠萝-香蕉处理和玉米-香蕉处理土壤pH值高于对照,且菠萝-香蕉处理效果优于玉米-香蕉处理;菠萝-香蕉和玉米-香蕉处理土壤可培养镰刀菌属数量均减少,根际可培养芽孢杆菌和假单胞菌的数量均增加,且菠萝-香蕉处理提高了土壤总细菌拷贝数.本研究表明菠萝和玉米轮作均能显著改善连作香蕉土壤生态环境,促进下茬香蕉生长,缓解连作生物障碍,并且联合生物有机肥施用后效果更优.