Effects of different regulatory methods on improvement of greenhouse saline soils, tomato quality, and yield.

Hou Maomao,Zhai Yaming,Shao Xiaohou

doi:10.1155/2014/953675

Abstract

To identify effective regulatory methods scheduling with the compromise between the soil desalination and the improvement of tomato quality and yield, a 3-year field experiment was conducted to evaluate and compare the effect of straw mulching and soil structure conditioner and water-retaining agent on greenhouse saline soils, tomato quality, and yield. A higher salt removing rate of 80.72% in plough layer with straw mulching was obtained based on the observation of salt mass fraction in 0~20 cm soil layer before and after the experiment. Salts were also found to move gradually to the deeper soil layer with time. Straw mulching enhanced the content of soil organic matter significantly and was conductive to reserve soil available N, P, and K, while available P and K in soils of plough layer with soil structure conditioner decreased obviously; thus a greater usage of P fertilizer and K fertilizer was needed when applying soil structure conditioner. Considering the evaluation indexes including tomato quality, yield, and desalination effects of different regulatory methods, straw mulching was recommended as the main regulatory method to improve greenhouse saline soils in south China. Soil structure conditioner was the suboptimal method, which could be applied in concert with straw mulching.

Highlights

Soil salinization is one of the most serious environmental problems and is increasing steadily in many areas of the world, in arid and semiarid regions [1]
In all 3 seasons, changes of soil Electrical Conductivity (EC) in plough layer were not obvious from October to the following February; this was probably because there were less evaporations after entering the winter, the vertical migration of soil saline was mild in this period, soil EC in plough layer of CK was significantly higher than that of other treatments, and water-retaining agent had some effects on decreasing soil EC in plough layer, while the effects were not evident as straw mulching and soil structure conditioner
The 3-year locating observation in this study showed that the 3 regulatory methods could all decrease the soil EC in plough layer; decreasing effects from high to low were straw mulching > soil structure conditioner > waterretaining agent

Summary

Introduction

Soil salinization is one of the most serious environmental problems and is increasing steadily in many areas of the world, in arid and semiarid regions [1]. Greenhouse vegetable cultivation is developing rapidly in China and accounts for 11.6% of the national agricultural acreage [4]. Tomato has quickly become one of the major vegetables grown in solar greenhouse in China because of its high potential yield, water productivity, and profitability [5]. Every year economic loss occurs because of the reductions in greenhouse tomato productivity caused by various environmental stresses, and salt stress is one distinct type of stress for plants. Hu et al [8] suggested that soil salt stress is the main factor that affects tomato yields, which can inhibit crop growth and development, reducing agricultural production. For tomato plant, salinity is the major factor to enhance Na+ uptake [9, 10], inhibit K+, Ca2+, and NO3− uptake [11, 12], damage cells [13], induce oxidative stress [2], and inhibit the activity of the key enzymes and photosynthesis [14, 15]

Methods

Results

Conclusion