Ling Ning, Deng Kaiying, Song Yang, Wu Yunchen, Zhao Jun, Raza Waseem, Huang Qiwei, Shen Qirong
Agricultural Ministry Key Lab of Plant Nutrition and Fertilization in Lower-Middle Reaches of the Yangtze River, Jiangsu Key Lab and Engineering Center for Solid Organic Waste Utilization, Nanjing Agricultural University, 210095, China.
Agricultural Ministry Key Lab of Plant Nutrition and Fertilization in Lower-Middle Reaches of the Yangtze River, Jiangsu Key Lab and Engineering Center for Solid Organic Waste Utilization, Nanjing Agricultural University, 210095, China.
Microbiol Res. 2014 Jul-Aug;169(7-8):570-8. doi: 10.1016/j.micres.2013.10.004. Epub 2013 Oct 30.
The application method for a novel bioorganic fertilizer (BIO) was developed to improve its biocontrol efficacy of Fusarium wilt (Ling et al. 2010). However, its efficacy on controlling Fusarium wilt and the variations of microbial community after long-term application for watermelon production had not been elucidated. To clarify, a 4-years pot experiment of mono-cropping watermelon was conducted. The results revealed that though the disease incidences were increased in all treatments with the increase of continuous cropping years, the treatment of BIO application both in nursery and pot soil always maintained the lowest disease incidence. The real-time PCR results showed that the population of Paenibacillus polymyxa was decreased with continuous cropping years, but in all seasons, the treatment with BIO application both in nursery and pot soil had a highest population of P. polymyxa than the other treatments. On the other hand, the abundance of the pathogen FON was increased with the increase of continuous cropping years and the lowest rate of increase was found by BIO application in both nursery and pot soil. DGGE patterns showed that the bacterial diversity was weakened after mono-cropping of watermelon for 4 years, but the consecutive applications of BIO at nursery and transplanting stage resulted in the minimal change of bacterial diversity. More detailed differences on bacterial diversity between control and double application of BIO treatment after 4-years monoculture were analyzed by 454 pyrosequencing, which showed the dominant phyla found in both samples were Firmicutes, Proteobacteria and Actinobacteria, and the consecutive applications of BIO recruited more beneficial bacteria than control, such as Bacillus, Paenibacillus, Haliangium, Streptomyces. Overall, these results, to a certain extent, approved that the consecutive applications of BIO at nursery and transplanting stage could effectively suppress watermelon Fusarium wilt by regulating the rhizosphere bacterial diversity. These results could give some clues that how to regulate the soil microbial community to an appropriate level which can keep the plant healthy and thus control the soil-borne diseases.
为提高新型生物有机肥（BIO）对枯萎病的生防效果，已研发出其施用方法（Ling等人，2010年）。然而，长期施用该肥料对西瓜生产中枯萎病的防治效果以及微生物群落变化尚未阐明。为了弄清楚这一点，开展了为期4年的西瓜单作盆栽试验。结果表明，尽管随着连作年限增加，所有处理的发病率均上升，但在育苗土和盆栽土中均施用BIO的处理发病率始终最低。实时荧光定量PCR结果显示，多粘芽孢杆菌数量随连作年限增加而减少，但在所有季节中，育苗土和盆栽土中均施用BIO的处理多粘芽孢杆菌数量均高于其他处理。另一方面，尖孢镰刀菌丰度随连作年限增加而上升，而在育苗土和盆栽土中均施用BIO的处理其上升速率最低。变性梯度凝胶电泳图谱显示，西瓜单作4年后细菌多样性减弱，但在育苗期和移栽期连续施用BIO导致细菌多样性变化最小。通过454焦磷酸测序分析了4年单作后对照与BIO双施处理之间细菌多样性的更详细差异，结果表明两个样品中主要的菌门均为厚壁菌门、变形菌门和放线菌门，连续施用BIO比对照招募了更多有益细菌，如芽孢杆菌属、多粘芽孢杆菌属、盐单胞菌属、链霉菌属。总体而言，这些结果在一定程度上证明，在育苗期和移栽期连续施用BIO可通过调节根际细菌多样性有效抑制西瓜枯萎病。这些结果可为如何将土壤微生物群落调节到能保持植物健康从而控制土传病害的适当水平提供一些线索。
