Abstract:

Bared soil causes the decline of soil fertility in the banana cropping system, which is one of the crucial factors limiting the sustainable development of banana industry. Plant covering could be an effective way to alleviate the decline of soil fertility in banana cropping system. The functional diversity of soil microbial communities could sensitively reflect the variation of soil properties, and is an important indicator for assessing soil quality. In this study, conventional planting method with bare soil between rows was used as control (CK), natural weeds covering (NW) and artificially planted legumes [Macroptilium atropurpureum (DC.) Urb.] covering (CP) were taken as the treatments in banana cropping system. The effects of plant covering on the functional diversity of soil microorganisms under banana cropping system were studied with microbial Biolog identification technology. The results showed that the carbon utilization of soil microorganisms had significant differences under different covering plants, ranked as: CP> NW> CK. Compared with CK, plant covering significantly (P<0.05) improved the Richness Index, Shannon-Wiener Index and Simpson Index of soil microorganisms under banana cropping system; the soil microorganisms showed a high utilization rate of sugars, amino acids and carboxylic acids. The soil microorganisms under NW showed better utilization of carboxylic acid carbon sources, and the soil microorganisms under CP showed better utilization of sugars and amino acid carbon sources. Different covering plants had significantly affected soil microbial community functional diversity under banana cropping system. Compared with CK, CP could improve the soil microbial community and effectively mitigate the degree of soil degradation. Promoting soil microbial diversity by covering plant diversity, the healthy and sustainable utilization of soil could be achieved in banana industry.

Key words: plant covering, banana, soil microorganism, Biolog-ECO, soil fertility