Autotoxicity of continuoulys cropped passion fruit (Passiflora edulis Sims) soil

2021 ◽  
Vol 53 (1) ◽  
pp. 101-110
Author(s):  
Q.X. Zhang ◽  
X.T. Chen ◽  
Y.C. Wang ◽  
Y.H. Wang ◽  
C.L. Zhu ◽  
...  

We determined the soil autotoxicity in the rhizosphere soil of passion fruit continued cropping up to 3 years, and analyzed the changes in the enzyme activity, microbial quantity and diversity in rhizosphere soil. The results showed that the autotoxicity of passion fruit rhizosphere soil increases with the increase in continuous cropping years. The microbial biomass carbon, microbial respiration, and the activity of enzymes (protease, urease and catalase) in passion fruit rhizosphere soil decreased with increases in passion fruit continuous cropping years. Contrarily, the activity of polyphenol oxidase was opposite, showing an upward trend. The results of BIOLOG eco-plate showed that the differences in soil carbon sources between different continuous cropping years were mainly amino acids, carboxylic acids, phenolic acids and amine carbon sources. The ratio of bacteria, bacteria/fungus ratio, actinomycetes, protozoa and total marker PLFA in the rhizosphere soil decreased significantly with the increase of soil planting years, while the total PLFA of fungi increased. Thus, with the increase of continuous cropping years of passion fruit, the soil autotoxicity was intensified and the soil enzyme activity and soil microbial diversity decreased.

2021 ◽  
Vol 49 (4) ◽  
pp. 12532
Author(s):  
Ali I. MALLANO ◽  
Xianli ZHAO ◽  
Yanling SUN ◽  
Guangpin JIANG ◽  
Huang CHAO

Continuous cropping systems are the leading cause of decreased soil biological environments in terms of unstable microbial population and diversity index. Nonetheless, their responses to consecutive peanut monocropping cycles have not been thoroughly investigated. In this study, the structure and abundance of microbial communities were characterized using pyrosequencing-based approach in peanut monocropping cycles for three consecutive years. The results showed that continuous peanut cultivation led to a substantial decrease in soil microbial abundance and diversity from initial cropping cycle (T1) to later cropping cycle (T3). Peanut rhizosphere soil had Actinobacteria, Protobacteria, and Gemmatimonadetes as the major bacterial phyla. Ascomycota, Basidiomycota were the major fungal phylum, while Crenarchaeota and Euryarchaeota were the most dominant phyla of archaea. Several bacterial, fungal and archaeal taxa were significantly changed in abundance under continuous peanut cultivation. Bacterial orders, Actinomycetales, Rhodospirillales and Sphingomonadales showed decreasing trends from T1>T2>T3. While, pathogenic fungi Phoma was increased and beneficial fungal taxa Glomeraceae decreased under continuous monocropping. Moreover, Archaeal order Nitrososphaerales observed less abundant in first two cycles (T1&T2), however, it increased in third cycle (T3), whereas, Thermoplasmata exhibit decreased trends throughout consecutive monocropping. Taken together, we have shown the taxonomic profiles of peanut rhizosphere communities that were affected by continuous peanut monocropping. The results obtained from this study pave ways towards a better understanding of the peanut rhizosphere soil microbial communities in response to continuous cropping cycles, which could be used as bioindicator to monitor soil quality, plant health and land management practices.


2019 ◽  
pp. 1578-1585
Author(s):  
Catia Aparecida Simon ◽  
Sebastião Ferreira de Lima ◽  
Meire Silvestrini Cordeiro ◽  
Vinícius Andrade Secco ◽  
Guilherme Nacata ◽  
...  

Carbon sources are exuded and deposited by different soil cover plants. They promote growth, diversity and enhancement of soil microbial community functionality, due to organic matter degradation by participating in major biochemical cycles and the availability of inorganic nutrients to plants. In this way, it is necessary to evaluate the microbiological attributes of the soil after cover cropping, which allows for surveying and monitoring the soil quality, thereby enabling rapid responses in relation to managing changes in the soil. Thus, the objective of this study was to evaluate soil microbiological attributes and soybean grain yield under the influence of different cover crops. The experiment was installed in the year 2015. The treatments were constituted by the following vegetation coverages: sorghum, millet, Urochloa ruziziensis, forage turnip, Urochloa brizantha, crambe and fallow area, with cover crops sown in succession to the soybean crop for three years prior to the date of installation of the experiment .The evaluated parameters were soil microbial biomass carbon, soil basal respiration, metabolic quotient, enzymatic activity of acid phosphatase and soil β-glucosidase, plant phytomass produced by the different cover crops and soybean yield in each area. The use of cover crops promotes higher soybean yield. The microbial activity and its efficiency were modulated according to the type of cover crop used. Soil under sorghum mulch provided lower microbial efficiency. The U. ruziziensis plant residues remain for less time on the soil. The results show that U. brizantha may be the most suitable for its use as a soil cover plant, providing improvements in its attributes.


2021 ◽  
Author(s):  
Jun Li ◽  
Xiaoyu Cheng ◽  
Wei Chen ◽  
Hanjie Zhang ◽  
Tianlang Chen ◽  
...  

Abstract Continuous cropping of cut chrysanthemum causes soil degradation and chrysanthemum quality decline, but the biotic and abiotic mechanisms behind it remain unclear. This impedes our ability to assess the true effects of continuous cropping on agricultural soil functions and our ability to repair impaired soils. Here we examined the impact of different replanting years on microbial communities and enzyme activities in rhizosphere soil of cut chrysanthemum (Chrysanthemum morifolium). Our results showed that soil total nitrogen (TN) and organic carbon (SOC) contents were significantly lower in the soil with 12 years of continuous cropping (Y12) than that in the soil with 1 year of cropping (Y1). Compared with Y1, Y12 treatment decreased alkaline phosphatase and β -glucosidase by 12.1 and 24.4%, but increased the activities of soil urease and catalase by 98.2 and 34.8%, respectively. Soil bacterial populations in Y6 (continuous cropping for 6 years) and Y12 treatments decreased by 52.3 and 87.5% compared with that in Y1 treatment. Moreover, the bacterial α-diversity (Shannon index) significantly decreased by 37.3 and 57.6% over 6 and 12 years of continuous cropping, respectively. Long-term monoculture cropping shifted the bacterial community composition, with decreased abundances of dominant phyla such as Proteobacteria and Acidobacteria, but with an increase in the relative abundances of Actinobacteria and Chloroflexi, and Gemmatimonadetes. Moreover, Y6 and Y12 treatments harbored less microbial network complexity, lower bacterial taxa, and fewer linkages among bacterial taxa, relative to Y1. Soil pH, SOC, and TN were the main edaphic factors affecting soil bacterial community compositions and diversity. Overall, our results demonstrate that continuous cropping has a significant negative impact on soil microbial diversity and complexity.


2021 ◽  
Vol 42 (5) ◽  
pp. 1370-1378
Author(s):  
S. Aechra ◽  
◽  
R.H. Meena ◽  
S.C. Meena ◽  
S.L. Mundra ◽  
...  

Aim: A field experiment was conducted during rabi season to determine the effect of biofertilizers and split application of vermicompost on biological properties (microbial biomass carbon and nitrogen, microbial populations and enzyme activities) in rhizosphere of wheat. Methodology: The experiment was laid out in factorial randomized block design with three replications consisting of twenty treatment combinations. Soil samples were collected from the plots at 0-15 cm depth after harvest of wheat crop and soil biological properties analyzed using standard analytical procedure. Results: The experiment results indicated that among biofertilizers treatments, seed inoculation with Azotobacter + PSB + KMB + ZnSB (B5) resulted in a significant higher soil microbial biomass carbon, microbial biomass nitrogen, population of bacteria, fungi and actinomycetes, dehydrogenase activity and acid phosphatase enzyme activity in comparison to control. Similarly, application of vermicompost as 50 % VC at sowing + 50 % VC at tillering (V3) were obtained improved microbial biomass carbon and nitrogen, microbial population, dehydrogenase activity and acid phosphatase enzyme activity while remaining at par with 75 % VC at sowing + 25 % VC at tillering (V4) proved superior in comparison to rest of the treatments due to continuous supply of nutrients throughout the crop cycle. Grain and straw yield of wheat also increased due to the application of biofertilizers and vermicompost over the control. Interpretation: Biofertilizers (Azotobacter, PSB, KMB and ZnSB) and split application of vermicompost enhanced the soil microbial population and enzymatic activities which sustained the soil health for better wheat production.


2020 ◽  
Vol 452 (1-2) ◽  
pp. 119-135 ◽  
Author(s):  
Hong Shen ◽  
Wenhui Yan ◽  
Xingyong Yang ◽  
Xinhua He ◽  
Xin Wang ◽  
...  

2020 ◽  
Vol 100 (6) ◽  
pp. 683-691
Author(s):  
Xiao-Ming Chen ◽  
Qi Zhang ◽  
Shao-Min Zeng ◽  
Yao Chen ◽  
Yong-Yan Guo ◽  
...  

The use of rain shelters in pear cultivation has been shown to improve yields and the appearance and quality of fruit, as well as reduce diseases and pests; however, how rain shelters affect soil chemical properties, soil enzyme activity, and soil microbial diversity remains unknown. Here, we studied pear trees under rain-shelter cultivation and open-field cultivation in the same orchard and compared fruit quality, soil chemical characteristics, soil enzyme activity, and soil microbial diversity. Results showed that rain shelters can significantly (p < 0.05) increase the sugar content (sweetness) of pear fruits and decrease the content of acids. The levels of available phosphorus, available potassium, organic matter, and water in soils under rain shelters were significantly (p < 0.05) lower than in soils in open fields. Rain-shelter treatment increased soil polyphenol oxidase activity and decreased phosphomonoesterase, urease, and sucrase activity. Analysis of microbial carbon-source utilization rates and microbial diversity showed that open-field cultivation is beneficial for microbial carbon-source utilization and microbial diversity in rhizosphere soil. Our study found that rain-shelter cultivation is not beneficial to soil fertility, microbial carbon-source metabolism and utilization, matter cycling, or microbial diversity and that the use of rain shelters may require appropriate nutrient and organic matter supplementation to maintain long-term cultivation of crops; whereas, the effects of environmental factors on open-field cultivation are greater, and more refined water and fertilizer management is required to improve fruit quality.


Agronomy ◽  
2020 ◽  
Vol 10 (11) ◽  
pp. 1675
Author(s):  
Manaka J. Makgato ◽  
Hintsa T. Araya ◽  
Christian P. du Plooy ◽  
Salmina N. Mokgehle ◽  
Fhatuwani N. Mudau

Plant-beneficial microorganisms are determinants of plant health and productivity. However, the effects associated with secondary plant metabolism and interactions in the rhizosphere for Cancer bush Lessertia frutescens (L.) is unclear. The study was conducted to understand the mechanism of rhizobium inoculation for L. frutescens, variations in phytochemicals, soluble sugars, and soil–plant interactions in the rhizosphere. Four rhizobium inoculation levels (0, 100, 200, and 400 g) were evaluated under the field conditions to establish the antioxidant properties, soluble sugars, and rhizosphere soil microbial diversity at 150, 240, and 330 days after planting (d.a.p). Although inoculation did not significantly affect plant biomass and N2 fixation of L. frutescens, total phenolics and flavonoids were enhanced with the application of 200 g at 240 days after planting. The antioxidant values analyzed through FRAP (Ferric reducing power assay) were highest with 100 g inoculation at 240 days after planting. Water-soluble sugars such as fructose, sucrose, and glucose increased with the application of 400, 200, and 100 g rhizobium inoculation. The rhizosphere′s carbon source utilization profiles (CSUP) did not vary significantly, depicting the weaker ability in converting C, P, and N profiles. The lowest ß glucosidase activity was observed in the bulk soil with the lowest alkaline and acid phosphatase activities. Soil microbial populations present in the bulk sample demonstrated the smallest overall enzyme activities. The variation of different variables studied indicate the potential of rhizobium inoculation. However, further studies are required to ascertain the inoculation′s effectiveness for plant growth and rhizosphere microbial populations of L. frutescens.


Sign in / Sign up

Export Citation Format

Share Document