Niu Yining, Bainard Luke D, May William E, Hossain Zakir, Hamel Chantal, Gan Yantai
Swift Current Research and Development Centre, Agriculture and Agri-Food Canada, Swift Current, SK, Canada.
State Key Laboratory of Aridland Crop Biology, Gansu Agricultural University, Lanzhou, China.
Front Microbiol. 2018 Aug 23;9:1909. doi: 10.3389/fmicb.2018.01909. eCollection 2018.
The association of plants and microbial communities is crucial for crop production, and host plants influence the composition of rhizosphere microbiomes. Pulse crops play an important role in the development of sustainable cropping systems, and producers in the Canadian prairies often increase the frequency of pulses in their cropping systems. In this study, we determined the shifts in the fungal community of pea ( L.) rhizosphere, as influenced by the frequency of pulses in rotation, using high throughput sequencing. Six cropping systems containing pea (P), lentil ( Medik., L), hybrid canola ( L., C), wheat ( L., W), and oat ( L., O) in different intensities were tested. The fungal communities were assessed at the flowering stage in the fourth and fifth year of the 4-year rotations. Cropping system had a significant impact on the composition of the rhizosphere fungal community, and the effect of crop rotation sequence was greater and explained more of the variation than the effect of previous crops. The rotation with consecutive pulses (WPLP) decreased fungal evenness and increased the proportion of pathotrophs. was a dominant and ubiquitous pathotrophic genus. , and were generally more abundant in pulse intensive rotations (WPLP, WLOP, and WPOP), the exception being which was not promoted by lentil. Reads of and were most abundant in pea preceded by lentil followed by the reads of in pea preceded by wheat. Pea consistently had higher grain yield when grown in diversified rotations including wheat, canola/lentil, and oat than rotations with two repeated crops (canola or pea). Cropping system affected the soil physicochemical properties, and soil pH was the main driver of fungal community shift. No evidence of beneficial microorganisms involvement in plant productivity was observed, but the high abundance of pathotrophs in pulse intensified rotations suggests the possibility of pathogen buildup in the soil with increasing pulse frequency. Diversifying rotation sequences minimized disease risk and increased pea production, in this study. Careful selection of plant species appears as a strategy for the management of rhizosphere fungal communities and the maintenance of crop production system's health.
植物与微生物群落的关联对作物生产至关重要，宿主植物会影响根际微生物群落的组成。豆类作物在可持续种植系统的发展中发挥着重要作用，加拿大草原地区的生产者经常在其种植系统中增加豆类作物的种植频率。在本研究中，我们使用高通量测序技术，确定了轮作中豆类作物种植频率对豌豆（L.）根际真菌群落的影响。测试了六种不同强度的种植系统，其中包含豌豆（P）、小扁豆（Medik., L）、杂交油菜（L., C）、小麦（L., W）和燕麦（L., O）。在4年轮作的第四年和第五年开花期对真菌群落进行评估。种植系统对根际真菌群落的组成有显著影响，与前茬作物的影响相比，轮作顺序的影响更大，解释的变异更多。连续种植豆类作物（WPLP）降低了真菌的均匀度，增加了致病营养型真菌的比例。是一个占主导地位且普遍存在的致病营养型属。在豆类作物密集轮作（WPLP、WLOP和WPOP）中，和通常更为丰富，但小扁豆并未促进的生长。在小扁豆之后种植的豌豆中，和的 reads 最为丰富，其次是在小麦之后种植的豌豆中的 reads。与两种重复作物（油菜或豌豆）的轮作相比，当豌豆种植在包括小麦、油菜/小扁豆和燕麦的多样化轮作中时，其籽粒产量始终较高。种植系统影响土壤理化性质，土壤pH是真菌群落变化的主要驱动因素。未观察到有益微生物参与植物生产力的证据，但豆类作物强化轮作中致病营养型真菌的高丰度表明，随着豆类作物种植频率增加，土壤中病原体积累的可能性。在本研究中，多样化轮作顺序可将病害风险降至最低并提高豌豆产量。谨慎选择植物物种似乎是管理根际真菌群落和维持作物生产系统健康的一种策略。
