Short-term complete submergence of rice at the tillering stage increases yield.

Yajie Zhang,Lei Li,Qun Zhou,Zhensheng Wang,Yao Xiao,Xing Wei,Mingyao Zhou

doi:10.1371/journal.pone.0127982

Abstract

Flooding is a major threat to agricultural production. Most studies have focused on the lower water storage limit in rice fields, whereas few studies have examined the upper water storage limit. This study aimed to explore the effect of waterlogging at the rice tillering stage on rice growth and yield. The early-ripening late japonica variety Yangjing 4227 was selected for this study. The treatments included different submergence depths (submergence depth/plant height: 1/2 (waist submergence), 2/3 (neck submergence), and 1/1 (complete submergence)) and durations (1, 3, and 5 d). The control group was treated with the conventional alternation of drying and wetting. The effects of waterlogging at the tillering stage on root characteristics, dry matter production, nitrogen and phosphorus accumulation, yield, yield components, and 1-aminocyclopropane-1-carboxylic acid synthase (ACS) gene expression were explored. Compared with the control group, the 1/1 group showed significant increases in yield, seed-setting rate, photosynthetically efficient leaf area, and OS-ACS3 gene expression after 1 d of submergence. The grain number per panicle, dry weight of the aboveground and belowground parts, and number of adventitious roots also increased. Correlation analysis revealed a significant positive correlation between the panicle number and nitrogen content; however, no significant correlation was found for phosphorus content. If a decrease in rice yield of less than 10% is acceptable, half, 2/3, and complete submergence of the plants can be performed at the tillering stage for 1-3 d; this treatment will increase the space available for rice field water management/control and will improve rainfall resource utilization.

Highlights

Flooding is a major threat to agricultural production
Each pot was filled with 18 kg of well-mixed, sifted surface soil, which was obtained from the preceding wheat field
Based on the results obtained in this study, the following conclusions can be drawn: 1. The decrease in rice yield can be controlled to 10% after the plants suffer from half, 2/3, and complete submergence for 1–3 d of field water storage; 2

Summary

Introduction

Flooding is a major threat to agricultural production. China is one of the largest agricultural production areas in the world, and large areas of the country are devoted to rice cultivation. Rice planting areas in China are primarily located in the southern region, which is characterized by heavy rainfall, humid conditions, and frequent flooding, as well as in northern low-lying swamp zones. Flooding has become a major threat to rice production, and the PLOS ONE | DOI:10.1371/journal.pone.0127982. Submergence Increases Rice Yield data collection and analysis, decision to publish, or preparation of the manuscript Flooding has become a major threat to rice production, and the PLOS ONE | DOI:10.1371/journal.pone.0127982 May 22, 2015

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