Effects of Rhizosphere Ventilation on Soil Enzyme Activities of Potted Tomato under Different Soil Water Stress

Abstract

In order to improve the growing environment of root zone, and investigate the effects of different rhizosphere ventilation environments on soil enzyme activities, we supplied gas for potted tomato by air compressor, and set three irrigation levels (70-90% field capacity). Each irrigation level has different ventilation volume coefficient (0.4, 0.8, 1.2, and 1.6) with the reference standard as 50% soil porosity. The results showed that the changing trend of soil catalase, urease, and dehydrogenase activity showed the first increase and then the decrease in the tomato growth period, and activities of soil catalase, urease, and dehydrogenase under the ventilation treatment are higher than those of the non-ventilation. When the irrigation level was 80% the field capacity and the ventilation coefficient was 0.8, the activities of three soil enzyme reached the highest value. Their activities of soil catalase, urease, and dehydrogenase were particularly sensitive to rhizosphere ventilation in fruit expanding process. Tomato had more dry matter accumulation and output under the ventilation treatment than that of the non-ventilation. The results prove that rhizosphere ventilation can improve the potted tomato root zone environment, increase the soil enzyme activity, and promote the nutrients uptake, thus promoting plant growth and fruit output and improving soil quality.

Effects of Artificial Soil Aeration Volume and Frequency on Soil Enzyme Activity and Microbial Abundance when Cultivating Greenhouse Tomato

“…This enzyme is also closely related to soil respiration intensity and microorganismal activities and is an important enzyme in the evaluation of soil fertility (Trasar-Cepeda et al, 1999). Throughout the growth period, the activities of the three enzymes exhibited an initial increase followed by a decrease, primarily because the rhizosphere soil enzyme activities were correlated with the growth stages, which is consistent with previous studies (Niu et al, 2012b). This phenomenon may occur because soil enzymes are secreted by crop roots and rhizosphere microorganisms and because the abundance of rhizosphere microorganisms is affected by root activity.…”

“…Artificial soil aeration can enhance air permeability and improve soil oxygen content, effectively relieving hypoxic stress on roots (Bhattarai et al, 2006(Bhattarai et al, , 2008(Bhattarai et al, , 2010Chen et al, 2011;Pendergast et al, 2013) while maintaining soil microorganism and enzyme activities (Niu et al, 2012b). Thus, soil moisture and soil aeration are coupled, and the soil water content influences soil aeration (Boone et al, 1986).…”

“…Our previous studies have also shown that artificial soil aeration can improve the tomato (Lycopersicon esculentum Mill.) root zone environment, increase soil enzyme activity, and promote the uptake of nutrients, thus promoting plant growth and fruit output and improving soil quality (Li et al, 2015a;Niu et al, 2012aNiu et al, , 2012b.…”

“…Because the tomato is one of the most sensitive species to water and air in the soil (Bradford and Yang, 1981), the present study used greenhouse tomatoes as its study subject. Higher tomato yields are related to higher oxygen contents in the soil root zone (Meek et al, 1983;Niu et al, 2012aNiu et al, , 2012b. Observed changes in plant growth were mainly because of the changes in nutrient cycling and physiological status, and soil-available nutrients were affected by soil microorganisms and soil enzyme activity.…”

Impact of post-infiltration soil aeration at different growth stages of sub-surface trickle-irrigated tomato plants

“…Artificial aeration has been shown to promote root metabolism and growth (Bortolini, 2005;Niu et al, 2012b;Su and Midmore, 2005), enhance nutrient absorption, and soil redoxase enzyme activity (Brzezińska et al, 2001a(Brzezińska et al, , 2001bNiu et al, 2012c), and accelerate the growth and yield of vegetables (Bhattarai et al, 2006;Nakano, 2007). Aeration through subsurface trickle irrigation tubes stimulated root growth (Bhattarai et al, 2006(Bhattarai et al, , 2008.…”