Yield reduction of direct-seeded rice under returned straw can be mitigated by appropriate water management improving soil phosphorus availability

2020 ◽  
Vol 71 (2) ◽  
pp. 134
Author(s):  
Haishui Yang ◽  
Jinxia Feng ◽  
Martin Weih ◽  
Yi Meng ◽  
Yifan Li ◽  
...  

The yield of direct-seeded rice has been shown to decrease after straw amendment. However, the reasons for the yield decrease, and any measures to alleviate it, are currently unknown. We hypothesised that straw return exerts negative effects on soil fertility and on root growth of direct-seeded rice, which subsequently reduces the remobilisation of reserves to grains under continuous flooding (CF); and that alternate wetting and drying (AWD) irrigation can alleviate these negative impacts. Field and greenhouse experiments were conducted to test the hypotheses, by comparing CF and AWD in combination with two wheat-straw treatments (incorporation and mulching). Under CF, wheat-straw incorporation decreased soil available phosphorus by 23–79%, root biomass by 10%, leaf biomass by 13%, and leaf area by 15% compared with the control with no straw incorporation; negative effects on these characteristics were lessened if the straw was mulched. The AWD treatment alleviated the negative effects of straw incorporation compared with CF, and straw mulching with AWD had no negative effects or resulted in positive effects. The results suggest that CF along with straw incorporation limits soil phosphorus availability, root growth and grain yield by affecting photosynthate accumulation and remobilisation. AWD irrigation mitigates these undesirable effects by decreasing soil total reductants, which subsequently increases soil pH and plant-available phosphorus. The proposed AWD treatment could be a promising strategy for the sustainable production of direct-seeded rice.

2011 ◽  
Vol 322 ◽  
pp. 43-46
Author(s):  
Shu Qing Guo ◽  
Xiang Yuan Dong

Hydrothermal humification (HTH) is a novel way to treat biomass in order to produce soil conditioner or organic fertilizer. A plant seed germination technique was used to assess the effect of HTH material derived from garden waste on seed germination, root elongation and germination index (GI) of cucumber at different stages of incubation. The incubation experiment was carried out with the mixture of HTH material and soil at a ratio of 1:3, 1:5 and 1:10 (HTH material:soil, wet weight) in soil. The results showed there are direct positive effects of the HTH material on seed germination and root growth. GI all were over 80%. High addition rates had non significantly negative effects on plant growth.


Agronomy ◽  
2021 ◽  
Vol 11 (12) ◽  
pp. 2442
Author(s):  
Zhenhao Zou ◽  
Lichao Fan ◽  
Xin Li ◽  
Chunwang Dong ◽  
Liping Zhang ◽  
...  

Biochar is widely used in agriculture to improve soil fertility and plant growth. However, a comprehensive assessment of how biochar amendment affects plant root growth is lacking. This study investigated the change in plant root biomass in response to biochar application, including impact factors such as the biochar feedstock and application rate, plant type, and soil pH. The Science Direct, Web Of Science, and Scopus databases were employed to search for literature published before 2021. The published papers with at least three replicates of biochar-amended treatments and a control at the same site were selected for meta-analysis. Our results showed that 165 (81.3%) of 203 datasets from 47 published studies indicated positive effects of biochar amendment on root growth with a mean relative increase of 32%. The feedstocks of biochar and its rate of application were the main factors that determined its effects on plant root growth. The increment of root biomass following biochar amendment was the greatest for trees (+101.6%), followed by grasses (+66.0%), vegetables (+26.9%), and cereals (+12.7%). The positive effects mainly depended on feedstock sources, with the highest positive effect (+46.2%) for gramineous, followed by woody plants (+25.8%) and green wastes (+21.1%). Linear regression analysis and SEM (Structural equation modeling) analysis showed that total nitrogen (TN) and available phosphorus (AK) are one of the most important factors affecting the increase of root biomass. These results suggest that biochar can be considered an effective amendment to improve root growth and soil fertility. Biochar feedstock sources, application rates, and plant types should be considered to assess the potential benefits of biochar for root growth and soil quality.


2020 ◽  
Vol 51 (5) ◽  
pp. 1436-1447
Author(s):  
Al-Jorani & et al.

The aim of this research was to study the effect of feeding of goat kids on Panicum Mombasa grass on productive traits, carcass characteristics and meat production. 25 of local cross breed male goat kids; average weight 18.3 kg were divided randomly to five treatments, the first one T1 was fed with wheat straw, T2 green alfalfa, T3 green Panicum Mombasa, T4 alfalfa hay and T5 Panicum Mombasa hay. Animals reared in single cages for two weeks as a preliminary period, the experiment period lasted for 70 days. Concentrate diet provided with 3% of body weight, roughage feeds provided freely. At the end of the experiment, three animals were slaughtered from each treatment randomly, data showed no positive effects were observed for feeding the Punicum Mombasa grass when compared with the traditional roughages feed used in Iraq for most of the productive traits and the carcasses and meat characteristics studied. At the same time, no negative effects were reported on the Punicum Mombasa feed in those traits and characteristics.


2015 ◽  
Vol 209 (2) ◽  
pp. 823-831 ◽  
Author(s):  
Deshan Zhang ◽  
Chaochun Zhang ◽  
Xiaoyan Tang ◽  
Haigang Li ◽  
Fusuo Zhang ◽  
...  

2020 ◽  
Author(s):  
Pengfa Li ◽  
Ming Liu ◽  
Guilong Li ◽  
Kai Liu ◽  
Tianshun Liu ◽  
...  

Abstract Background The soil disease-suppressiveness may depend on complex interactions between pathogens and microbiome in response to limiting nutrients. However, these interactions remain poorly understood. Thus, we investigated the significance of soil available phosphorus (AP) in modulating pathogen-microbiome interactions for the emergence or suppression of peanut wilt using receiver operating characteristic curve (ROC) analysis and structural equation modeling (SEM) approaches. Results We observed significant differences in the relative abundance of pathogenic and beneficial microbes, alpha- and beta-diversity indices between disease-conducive and -suppressive soils. The pathogenic ( Ralstonia) and beneficial ( Burkholderia and Bacillus ) taxa dominated the rhizosphere of wilted and healthy peanut plants. The rhizosphere of healthy rather than wilted plants showed significantly higher microbial biodiversity. Moreover, co-occurrences between Ralstonia and microbiome species were highly positive and negative in the disease-conducive and -suppressive soil, respectively, thus predicting facilitative ( Rudaea ) and suppressive ( Burkholderia , Enterobacter , Bacillus ) role of indigenous microbes in Ralstonia invasion in soil. Moreover, both ROC and SEM analyses revealed that Ralstonia invaded rhizospheric microbial networks and caused peanut wilt, very likely by competently utilizing soil phosphorus under copiotrophic (high AP) than oligotrophic (low AP) conditions. Conclusion Our results suggest the importance of soil phosphorus availability in altering the interactions between pathobiome and beneficial microbiome. Our study concludes that feeding soil with labile nutrients could deplete microbial biodiversity and interactions while paving the way for pathogen invasion.


2018 ◽  
Vol 62 (2) ◽  
pp. 97-107 ◽  
Author(s):  
Nina Keith

Abstract. The positive effects of goal setting on motivation and performance are among the most established findings of industrial–organizational psychology. Accordingly, goal setting is a common management technique. Lately, however, potential negative effects of goal-setting, for example, on unethical behavior, are increasingly being discussed. This research replicates and extends a laboratory experiment conducted in the United States. In one of three goal conditions (do-your-best goals, consistently high goals, increasingly high goals), 101 participants worked on a search task in five rounds. Half of them (transparency yes/no) were informed at the outset about goal development. We did not find the expected effects on unethical behavior but medium-to-large effects on subjective variables: Perceived fairness of goals and goal commitment were least favorable in the increasing-goal condition, particularly in later goal rounds. Results indicate that when designing goal-setting interventions, organizations may consider potential undesirable long-term effects.


2016 ◽  
Vol 28 (3) ◽  
pp. 123-135 ◽  
Author(s):  
Raffael Heiss ◽  
Jörg Matthes

Abstract. This study investigated the effects of politicians’ nonparticipatory and participatory Facebook posts on young people’s political efficacy – a key determinant of political participation. We employed an experimental design, using a sample of N = 125 high school students (15–20 years). Participants either saw a Facebook profile with no posts (control condition), nonparticipatory posts, or participatory posts. While nonparticipatory posts did not affect participants’ political efficacy, participatory posts exerted distinct effects. For those high in trait evaluations of the politician presented in the stimulus material or low in political cynicism, we found significant positive effects on external and collective efficacy. By contrast, for those low in trait evaluations or high in cynicism, we found significant negative effects on external and collective efficacy. We did not find any effects on internal efficacy. The importance of content-specific factors and individual predispositions in assessing the influence of social media use on participation is discussed.


2019 ◽  
pp. 59-73 ◽  
Author(s):  
Nikolai M. Svetlov ◽  
Renata G. Yanbykh ◽  
Dariya A. Loginova

In this paper, we assess the effects of agricultural state support of corporate farms on their revenues from agricultural production sales in 14 Russian regions that differ in technology, environment and institutional conditions. In addition to the direct effect of the state support, the indirect effects via labor and capital are revealed. For this purpose, we identify production functions and statistical models of production factors for each of these regions separately. We find out diverse effects of the state support on revenues among the regions. Positive effects prevail. Negative effects are mainly caused by labor reductions that follow subsidy inflows. Another cause of negative effects is the soft budget constraints phenomenon.


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