Plant Species Mediate Rhizosphere Microbial Activity and Biodegradation Dynamics in a Riparian Soil Treated with Bensulfuron-methyl

Song

et al. 2013

Microbial community responses to alternative management may be indicative of soil quality change. In this study, soils were collected from research plots over one year. The rhizosphere soils were studied by measuring microbial abundance (bacteria, fungi, actinomycetes, and ammonifiers), enzyme activities (invertase, catalase, urease, and phosphatase), and their relationship. Rhizosphere microbial abundance of different plant species varied greatly across seasons. The rhizosphere environment generated by Phragmites australis and Echinochloa crus-galli is suitable for microbial growth. In addition, the significant differences in rhizosphere enzyme activities of different plant species across seasons were also observed. There was a significant linear correlation between rhizosphere soil enzyme activities and microbial abundances except for between bacteria and catalase and between fungi and urease, but no such significant relationship was found between all rhizosphere soil microbial abundance and phosphatase except between fungi and acid phosphatase. We concluded that different plant species in coastal areas have different rhizosphere soils, due to the impact of the different root exudates and plant residues of the microbial properties.

Section: Discussionmentioning

confidence: 91%

Seasonal Dynamics of Rhizosphere Soil Microbial Abundances and Enzyme Activities under Different Vegetation Types in the Coastal Zone, Shandong, China

Song

et al. 2013

“…At the latter stage, the tomato root activity decreased as the root reached senescence, during which the root activity between the treatments was not significant. Rhizosphere ventilation treatments could significantly enhance root activity [17][18][19][20][21][22][23][24][25][26][27][28][29], increase root absorption capacity [12][13][14][15][16][17][18][19], and promote the growth of aerial parts of tomato. The effects of ventilation treatment in the M soil moisture treatment on root activity were relatively larger, indicating that the appropriate combination of water vapor can effectively promote tomato root growth, thus contributing to promote the tomato plant height, stem diameter, and leaf area growth [19][20][21][22][23][24][25][26][27][28][29].…”

Section: Influences On Root Vitalitymentioning

confidence: 99%

Effects of Soil Rhizosphere Aeration on the Root Growth and Water Absorption of Tomato

Niu

et al. 2012

Soil rhizosphere aeration status is an important aspect of soil quality and soil ecology. The objective of the current study was to determine the appropriate moisture environment that facilitates rhizosphere soil aeration and ensures normal root respiration in tomato. In the potted experiment, five treatments of soil aeration were used (0.4, 0.8, 1.2, 1.6 ventilation volume of 50% porosity of soil, and no ventilation) under conditions of the different soil moisture upper limits. The effects of different rhizosphere soil aerations on the physiological indicators and water absorption of tomato were studied. Under the same soil moisture condition, plant growth and root vitality initially increased, and then decreased when the soil ventilation volume increased. The combination of soil moisture with 80% of field capacity and 0.8 ventilation volume with 50% soil porosity raised the chlorophyll content by 29.98% and the root vitality by 61.55%, as compared with the non-ventilated treatment. Therefore, the appropriate volume of rhizosphere ventilation can effectively improve the capacity of water absorption in tomato. The result provides a new view about soil quality and soil ecology in terms of soil-root system.

“…Soil urease is produced by soil microbes; it can catalyze the decomposition of urea into ammonia, carbon dioxide, and water that is beneficial for plants absorption, which is important for improving the utilization of soil nitrogen and promoting nitrogen cycle. Dehydrogenase mainly live in living biological cells can catalyze redox reactions and promote the dehydrogenation of organic matter, which is an important sensitive indicator of soil activity and quality 35–47. In addition to soil moisture, temperature, and humidity can affect soil enzyme activity.…”

Section: Introductionmentioning

confidence: 99%

“…Soil air permeability and soil air composition and other factors can also affect soil enzyme activity. Therefore, the effect of rhizosphere ventilation on soil enzyme activity for potted tomato is significant to elucidate the principles of rhizosphere ventilation that can improve soil quality and promote plant growth, further optimizing the cultivation technology of potted tomato 23, 24, 39–47. Many scholars study the soil permeability and soil air components in combination with plant growth, the results showed that soil has higher carbon dioxide content and lower oxygen content compared to atmosphere.…”

Section: Introductionmentioning

confidence: 99%

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

Niu

Zang

et al. 2011

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.