Effects of Continuous Plastic Film Mulching on Soil Bacterial Diversity, Organic Matter and Rice Water Use Efficiency

Meiyan Wu,Ruochao Hao,Lianghuan Wu

doi:10.4236/gep.2016.44001

Abstract

Two field experiments were conducted to study the effects of 6-year plastic film mulching on bacterial diversity, organic matter of paddy soil and water use efficiency on different soils with great environmental variabilities in Zhejiang Province, China, under non-flooding condition. The experiment started in 2001 at two sites with one rice crop annually. Three treatments included plastic film mulching with no flooding (PM), no plastic film mulching and no flooding (UM), and traditional flooding management (TF). Soil samples were collected and analyzed for bacterial diversity by DGGE and organic matter content, and water use efficiency (WUE) was calculated. The results showed that PM treatment favored the development of a more total bacterial community compared with TF management, the total number of bands was 33.3, 31.7 at tiller stage and heading stage (p < 0.05*). Hence, organic matter content was decreased by 36.7% and 51.4% under PM at two sites. PM also produced similar rice grain yield as TF at Duntou site and Dingqiao site, the average was 7924 kg?ha?1 and 7015 kg?ha?1 for PM and 8150 kg?ha?1 and 6990 kg?ha?1 for TF, respectively. Compared to TF, WUE and irrigation water use efficiency were increased significantly by 70.2% - 80.4% and 273.7% - 1300.0% for PM. It is essential to develop the water-saving agriculture.

Highlights

Rice (Oryza sativa L.) is one of the major staple food crops in China
The DGGE fingerprinting of PCR-amplified 16S rDNA was shown in Figure 1(a) and Figure 1(b), which was extracted from the soils with different treatments at tiller and heading stages
The total number of bands was 31.7, 20.0, 28.3 for PM, traditional flooding management (TF), and UM treatment, respectively (p < 0.05*). These changes in the number of bands suggest that PM treatment favored the development of a more total bacterial community compared with TF management

Summary

Introduction

Rice (Oryza sativa L.) is one of the major staple food crops in China. About 86% of the total water in China hasHow to cite this paper: Wu, M.Y., Hao, R.C. and Wu, L.H. (2016) Effects of Continuous Plastic Film Mulching on Soil Bacterial Diversity, Organic Matter and Rice Water Use Efficiency. Plastic film mulching with no flooding (PM) has been adopted and developed as a new rice cultivation technique in China since the 1980s, and the total planting area under this management regime has reached 100,000 ha [2]. PM regime plastic film is used during rice-planting stages under non-flooded conditions, and only 30 - 50 mm per irrigation is applied when soil water content falls below 80% of soil field capacities from transplanting to tiller stage. The use of this new cultivation regime has led to soil temperature and the growth of weeds has been inhibited [3]

Objectives

Methods

Results