Growth and yield responses to amendments to the sugarcane monoculture: towards identifying the reasons behind the response to breaks

2011 ◽  
Vol 62 (9) ◽  
pp. 776 ◽  
Author(s):  
A. L. Garside ◽  
M. J. Bell

Experiments involving breaks to the sugarcane monoculture, soil fumigation and the application of biocides were conducted in Bundaberg, the Burdekin Valley and at Tully, three sugarcane-growing regions in Queensland, Australia. The aim was to elucidate the cause(s) of previously observed positive yield responses to breaks in the monoculture and assess persistence into a subsequent cane cycle. In all three experiments there was a positive response in the plant cane crop to fumigation of land that was under sugarcane monoculture, the response being 32, 39 and 21% for the Burdekin, Tully and Bundaberg experiments, respectively. Further, at Tully, the response was maintained into the ratoons. Fumigation after breaks also enhanced yields but the results were variable and were generally less than the response following sugarcane monoculture. At Tully, fumigating after bare fallow, grain crop and pasture breaks enhanced cane yields by 23, 26 and 29%, respectively, while in the Burdekin, responses to fumigation were much smaller at 9% (bare fallow), 4% (grain crop) and 8% (pasture). In Bundaberg, responses ranged from nil following a long-term (70 months) grass pasture up to 35% following a short-term (12 months) grass pasture, with a general trend for the response to fumigation being larger following short-term than long-term breaks. In the Tully experiment, biocides had variable effects on sugarcane growth and yield. Fungicide application produced as good a yield as fumigation whereas nematicides had little direct influence. However, when combined with fungicides, nematicides provided a synergistic effect in terms of shoot development. The results suggested that at the Tully site, fungi were the major detrimental biota associated with poor yields in long-term sugarcane monoculture, but nematodes had some influence once fungi were controlled. In two additional experiments at Bundaberg and Burdekin, it was shown that if the cane stool was removed after the plant crop (Bundaberg) and second ratoon (Burdekin) and sugarcane re-planted, there were no residual effects of breaks and fumigation. Thus it appears that the positive effects of breaks and fumigation measured in the ratoons were more associated with the development of a healthy stool in the plant crop than any residual effect on soil biota. In general the similarly positive response to fumigation and breaks indicated that a considerable part of the overall response to breaks was due to reducing the adverse effect of detrimental soil biota (largely fungi although there was an effect on nematodes). The type and duration of break was also important with long-term pasture being the most effective. However, the duration of the fumigation and break effects on soil biota only lasted for the plant crop.

2011 ◽  
Vol 62 (5) ◽  
pp. 396 ◽  
Author(s):  
A. L. Garside ◽  
M. J. Bell

Yield decline has been a major issue limiting productivity improvement in the Australian sugar industry since the early 1970s and is suspected to be largely due to growing sugarcane in a long-term monoculture. In order to address this issue, rotation experiments were established in several sugarcane-growing regions in Queensland, Australia, to ascertain whether breaking the sugarcane monoculture could, at least in part, assist in overcoming yield decline. The rotation experiments involved other crop species, pasture and bare fallow for different periods of time. When cane was replanted, the growth and yield following breaks was compared with that in a sugarcane monoculture system where the soil was unamended or fumigated before replanting. Yield increases were recorded in the plant and first ratoon (R1) crops in all experiments: in response to soil fumigation (average of 42 and 18%, respectively), and breaks (average of 27 and 30%, respectively). The data indicated that the response to breaks, while smaller in the plant crop, may have greater longevity than the response to fumigation. Further, there were indications that the response to breaks could continue into later ratoons (R2 and R3). Break type had little overall effect with the average response in the plant and R1 crops being 35% for breaks in excess of 30 months. Breaks of longer duration produced larger yield responses: 17% (<12 months), 24% (18–30 months) and 28% (>30 months) in the plant crop. However, the average yield increase over a plant and three ratoon crops when one cane crop was missed (6–12 months’ break) and a grain legume or maize break included was ~20%. Yield increases with breaks and fumigation were due to either increased stalk number, increased individual stalk weight or a combination of both. The component accounting for the majority of the variance changed between experiments, with a general trend for individual stalk weight to have more impact under better late season growing conditions and/or conditions that hampered early stalk development, while stalk number was more important under conditions of late season water stress and/or low radiation input. The results demonstrate that the long-term sugarcane monoculture is having an adverse effect on productivity. Further, breaking the sugarcane monoculture and sacrificing one sugarcane crop is likely to have minimal impact on the supply of cane to the mill. The increase in yield during other stages of the cane cycle is likely to compensate for the loss of 1 year of sugarcane, especially as the crop that is sacrificed is the last and almost always lowest-yielding ratoon.


Nutrients ◽  
2021 ◽  
Vol 13 (3) ◽  
pp. 1019
Author(s):  
Barbara Frączek ◽  
Aleksandra Pięta ◽  
Adrian Burda ◽  
Paulina Mazur-Kurach ◽  
Florentyna Tyrała

The aim of this meta-analysis was to review the impact of a Paleolithic diet (PD) on selected health indicators (body composition, lipid profile, blood pressure, and carbohydrate metabolism) in the short and long term of nutrition intervention in healthy and unhealthy adults. A systematic review of randomized controlled trials of 21 full-text original human studies was conducted. Both the PD and a variety of healthy diets (control diets (CDs)) caused reduction in anthropometric parameters, both in the short and long term. For many indicators, such as weight (body mass (BM)), body mass index (BMI), and waist circumference (WC), impact was stronger and especially found in the short term. All diets caused a decrease in total cholesterol (TC), low-density lipoprotein cholesterol (LDL-C), and triglycerides (TG), albeit the impact of PD was stronger. Among long-term studies, only PD cased a decline in TC and LDL-C. Impact on blood pressure was observed mainly in the short term. PD caused a decrease in fasting plasma (fP) glucose, fP insulin, and homeostasis model assessment of insulin resistance (HOMA-IR) and glycated hemoglobin (HbA1c) in the short run, contrary to CD. In the long term, only PD caused a decrease in fP glucose and fP insulin. Lower positive impact of PD on performance was observed in the group without exercise. Positive effects of the PD on health and the lack of experiments among professional athletes require longer-term interventions to determine the effect of the Paleo diet on athletic performance.


Author(s):  
Valentina Tocchioni ◽  
Alessandra Petrucci ◽  
Alessandra Minello

In the last years, there has been a large increase in high-educated and high-skilled people’s mobility as a consequence of the internationalization and globalization, the weakening of research and university systems of sending countries (the “brain drain” process), the increase in skilled demand and improvements in higher education of host countries (the “brain gain” process). At the micro-level, academic mobility has positive consequences on occupational prospects and careers of researchers, both in the short- and long- run. Nevertheless, numerous research studies have demonstrated the challenges of engaging in international academic mobility for people with caring responsibilities, particularly women. Using Italian data on occupational conditions of PhDs collected in 2018 by Istat and modelling multinomial logistic regression analyses, we intend to verify if female researchers are associated with a lower international mobility irrespective their field of study, and the extent to which gender interacts differently in the various fields of study in affecting the probability of moving abroad after PhD qualification. Also, the distinction between long-term and short-term mobility, which has been mainly neglected in the literature concentrating on longer stays, has taken into account. In this respect, short-term mobility is a potentially high-value investment that may be pursued also by those researchers and scientists who cannot move for longer periods, such as women with caring responsibilities. In the literature, it is acknowledged that an experience abroad during early career may have positive effects on future occupational prospects. With our work, we intend to shed light on potential disparities on moving abroad that may exist among researchers in their early career by gender, and which could contribute to leave behind women in academia.


Author(s):  
Dhani Ichsanuddin Nur

Background: The research purpose to analyzing impacts of funding source changes on pharmacy company profits that went public on Indonesian Stock Exchange, with analysis period of 2008 to 2013. Methods: The research applied analysis means in line with requirements of change variable measurements of funding sources in its interconnectedness with company profits; the applied model was Auto-regressive. Results: The research results indicated that changes of the last one-period short term debts had negative effects insignificantly on company profits, the last two-period short term debts had positive effects significantly on company profits, changes of the last one-period and two-period long term debts had negative effects insignificantly on company profits, equity changes of the last period had positive effects significantly on company profits, the last period profit changes had negative effects significantly on company profits. Conclusion: Last one-period short term, last one-period long term, last two-period long term debt changes, and last period profit have negative insignificant effect on company profit. Last two-period short term debt changes, last one-period equity changes, and last two-period equity changes have positive significant effect on company profit.


2020 ◽  
Vol 182 (4) ◽  
pp. 405-411
Author(s):  
S H Donze ◽  
L Damen ◽  
E F Mahabier ◽  
A C S Hokken-Koelega

Objective Children with Prader–Willi syndrome (PWS) have mild to moderate cognitive impairment. Short-term studies showed positive effects of growth hormone (GH) on cognitive development. This study investigated the effects of 8 years of GH on cognitive development in children with PWS. We also investigated whether starting GH during infancy results in higher cognitive functioning after 8 years of GH. Design Longitudinal study in 43 children with PWS during 8 years of GH (median age at GH start 8.1 years). Cognitive functioning after 8 years was compared to another group of 22 children with PWS (median age at GH start 1.4 years). Methods Cognitive functioning was measured by Wechsler Intelligence Scale for Children. Vocabulary, Similarities and Block Design subtests were expressed as standard deviation scores (SDS) and total IQ (TIQ) calculated. Results Estimated mean (95%CI) Block Design SDS changed from −2.2 (−2.6; −1.8) at GH start to −1.8 (−2.2; −1.4) after 8 years of GH (P = 0.18), similarly SDS from −1.5 (−2.1; −0.9) to −1.3 (−1.9; −0.7, P = 0.66) and TIQ from 66 (60; 72) to 69 (63; 75, P = 0.57). Vocabulary SDS remained similar, being −1.9 (−2.3; −1.4) at GH start and −1.9 (−2.4; −1.5) after 8 years (P = 0.85). After 8 years of GH Vocabulary, SDS and TIQ were higher in the children who started GH during infancy, compared to those who started GH later in childhood (P < 0.01, P = 0.04, respectively). Conclusions Cognitive functioning in children with PWS remains similar during long-term GH and develops at the same pace as healthy peers.


2018 ◽  
Vol 69 (1) ◽  
pp. 17-28
Author(s):  
Heide Spiegel ◽  
Teresa Mosleitner ◽  
Taru Sandén ◽  
Johann G. Zaller

Summary Organic fertilization has been shown to benefit soil biota. A field experiment was established in 1991 at the AGES experimental research station Ritzlhof to investigate the effects of long-term fertilization on soil biota and crop yields. Experimental plots were cultivated using a crop rotation with maize, wheat, barley, and pea. Eight treatments consisted of compost application (urban organic waste, green waste, cattle manure, and sewage sludge compost). Composts were applied exclusively (organic) or amended with mineral nitrogen (N) fertilizers (80 kg N ha−1, organic-mineral) and compared to 0 (control) and mineral (40, 80, and 120 kg N ha−1) fertilization. Earthworm activity and biomass, litter decomposition, crop growth, and yield parameters were investigated under winter barley (Hordeum vulgare L.) in 2014 after uniform mineral fertilization and 1.5 years after the last compost application. Earthworm activity was significantly increased under long-term organic-mineral fertilization compared to the control, whereas earthworm biomass was unaffected by compost application. Litter decomposition rate was highest in the control. Only barley stem growth was affected by fertilization, whereas other barley parameters including yield were unaffected. The results showed that long-term fertilization affects soil biota even if compost is not applied every year.


Author(s):  
Erika dos Santos Souza ◽  
Albertina P. Lima ◽  
William E. Magnusson ◽  
RICARDO ALEXANDRE KAWASHITA-RIBEIRO ◽  
Rodrigo Ferreira Fadini ◽  
...  

Ecological succession in tropical savannas is limited by seasonal fire, which affects habitat quality. Although fire may cause negligible or positive effects on animals occupying savannas, most short-term studies (months to a few years) are based on a single temporal sampling snapshot, and long-term studies (decades) are rare. We sampled four lizard species in Amazonian savannas to test the effects of fire and vegetation cover on lizard densities at two temporal scales. In the short-term, we use three sampling snapshots to test the effects of fire and vegetation cover on estimated lizard densities over the subsequent 1–5 years. In the long-term, we test the effects of fire and changes in vegetation cover over 21 years on current lizard density differences. In the short-term, species responses were usually consistent with foraging and thermoregulation modes. However, the results were not consistent among species and years, although the variances in species density explained by year as a random factor were generally low. In the long-term, the main effects of fire and vegetation cover show that lizard densities may change spatially, but not necessarily temporarily. Wildfire is a natural resource of savannas and apparently have little impact on resident lizards of that ecosystem.


Sports ◽  
2019 ◽  
Vol 7 (6) ◽  
pp. 148 ◽  
Author(s):  
Nadja Walter ◽  
Lucie Nikoleizig ◽  
Dorothee Alfermann

(1) Background: Self-talk (ST) is used to influence athletes’ thoughts, feelings, and behaviors. Samples of squad and competitive athletes are underrepresented, although research has proven the positive effects of ST in the context of sports. Thus, the present study focused on the impact of ST on psychological and performance outcomes of junior sub-elite athletes. (2) Methods: N = 117 athletes (55 females, 62 males; M = 16.0 years) were randomly assigned to either one of two experimental groups or to a control group (n = 30). The experimental groups received an ST intervention for either one week (n = 36) or eight weeks (n = 38), and the control group received no ST training. The dependent variables (competitive anxiety, volitional skills, self-efficacy, and coaches’ performance ratings) were assessed three times before and after the intervention. It was expected that (a) an ST intervention would reduce the competitive anxiety and increase volitional skills, self-efficacy, and performance; and, (b) long-term training would lead to higher effects than short-term training. (3) Results: As expected, ST training led to (less) somatic state anxiety and (higher) state self-confidence, self-optimization, self-efficacy, and performance. Additionally, long-term training was more effective than short-term training. (4) Conclusions: Targeted ST interventions may help to improve junior athletes’ psychological states and performance.


2020 ◽  
Vol 22 (2) ◽  
pp. 135-142

This review provides an overview of the literature regarding digital technology use and adolescent well-being. Overall, findings imply that the general effects are on the negative end of the spectrum but very small. Effects differ depending on the type of use: whereas procrastination and passive use are related to more negative effects, social and active use are related to more positive effects. Digital technology use has stronger effects on short-term markers of hedonic well-being (eg, negative affect) than long-term measures of eudaimonic well-being (eg, life satisfaction). Although adolescents are more vulnerable, effects are comparable for both adolescents and adults. It appears that both low and excessive use are related to decreased well-being, whereas moderate use is related to increased well-being. The current research still has many limitations: High-quality studies with large-scale samples, objective measures of digital technology use, and experience sampling of well-being are missing.


Agronomy ◽  
2021 ◽  
Vol 11 (3) ◽  
pp. 577
Author(s):  
Fang He ◽  
Björn Thiele ◽  
David Kraus ◽  
Souhaila Bouteyine ◽  
Michelle Watt ◽  
...  

Vegetable product quality is an important consideration for consumers. Long-term root cooling could improve certain food quality of horticultural crops, but often comes at the expense of reduced shoot biomass or yield. Since few studies have investigated how fast Chinese broccoli (Brassica oleracea var. alboglabra Bailey) responds to changes of root temperature, we shortened the duration of the root cooling treatment to one week before harvest to make the production system more effective. The aim of this study was to improve the food quality of Chinese broccoli without causing deleterious effects on plant growth and yield. The seedlings were cultivated hydroponically at two root temperatures (10 and 20 °C) during the last week prior to harvest in summer 2018 (Exp-1) and autumn 2019 (Exp-2). Plant growth, yield, physiological variables, soluble sugars, total chlorophyll, glucosinolates and mineral elements concentration were examined. The results showed that the yield reduction was alleviated compared to results over the long-term. Specifically, yield was not affected by root cooling in Exp-1 and reduced by 18.9% in Exp-2 compared to 20 °C. Glucose and fructose concentrations of the leaves were increased when the root temperature was 10 °C in both experiments with a more pronounced impact in Exp-2. In addition, root cooling produced a significant accumulation of individual glucosinolates, such as progoitrin, gluconapin, 4-methoxyglucobrassicin and 4-hydroxyglucobrassicin, in the stems of Exp-1 and the leaves of Exp-2. Minerals, such as N, showed reductions in the shoot, but accumulation in the root. Therefore, compared to long-term root cooling, short-term (one week) reduction of the root temperature is more economical and could help improve certain quality characteristics of Chinese broccoli with less or even no yield reduction.


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