How insects promote crop pollination remains poorly understood in terms of the contribution of functional trait differences between species. We used meta-analyses to test for correlations between ...community abundance, species richness and functional trait metrics with oilseed rape yield, a globally important crop. While overall abundance is consistently important in predicting yield, functional divergence between species traits also showed a positive correlation. This result supports the complementarity hypothesis that pollination function is maintained by non-overlapping trait distributions. In artificially constructed communities (mesocosms), species richness is positively correlated with yield, although this effect is not seen under field conditions. As traits of the dominant species do not predict yield above that attributed to the effect of abundance alone, we find no evidence in support of the mass ratio hypothesis. Management practices increasing not just pollinator abundance, but also functional divergence, could benefit oilseed rape agriculture.
There is a growing concern in society about the continuing intensive usage of pesticides in farming and its effects on environmental and human health. Insight in the intentions of farmers to reduce ...pesticide use may help identify pathways towards farming systems with reduced environmental impacts. We used the Reasoned Action Approach to identify which social-psychological constructs determine farmers' intentions to decrease pesticide use. We analysed 681 responses to an online survey to assess which constructs drive intention, and identified which beliefs pose barriers and drive the motivation of farmers to decrease pesticide use. Our results show that the intention to reduce pesticide use is strongly determined by whether other farmers also act. Furthermore, farmers perceive limited capacity and autonomy to reduce pesticide use, and motivations to reduce pesticide use were based on environmental considerations. Finally, decreasing pesticide use was considered risky, but the relative importance of risk attitude was offset by the environmental considerations of farmers. This indicates that farmers need successful examples of how to decrease pesticide use, either via exchange with peer farmers or knowledge provisioning on alternative pest control methods. These insights may be useful to direct policy making to influence farmers' intentions to decrease pesticide use.
•Farmers' intention to reduce pesticide use was strongly determined by whether other farmers also act.•Farmers perceived limited capacity and autonomy to reduce pesticide use.•Farmers motivations to reduce pesticide use were based on environmental considerations.•Decreasing pesticide use was considered risky, but the relative importance of risk attitude was offset by the environmental considerations of farmers.
Background and aims
Myocardial infarction triggers an inflammatory response involved in cardiac repair. We studied the association of the interleukin 6 (IL-6) cascade with infarct size and cardiac ...function after ST-elevation myocardial infarction (STEMI).
Methods
In 369 STEMI patients IL-6, soluble IL-6 receptor (sIL-6R), and soluble glycoprotein (sgp) 130 were measured at baseline (hospital admission), 24 h, 2 weeks, 7 weeks, 4 months, and 1 year post-PCI and sIL-6R/IL-6 ratio was calculated. At 4 months, infarct size and left ventricular ejection fraction (LVEF) were assessed by magnetic resonance imaging. Diastolic function (
E
/
e
′) was determined by echocardiography.
Results
Hospital admission levels for IL-6, sIL-6R, sgp 130 were 3.7 pg/ml (IQR 2.1–6.7 pg/ml), 51.6 ng/ml (IQR 37.3–69.0 ng/ml), and 332 ng/ml (IQR 280–399 ng/ml), respectively. 24 h after admission, IL-6 had increased threefold compared to baseline (
p
< 0.001) and returned below baseline (
p
< 0.001) 2 weeks after STEMI. sIL-6R and sgp130 levels at 24 h remained similar to baseline but were increased at 2 weeks (
p
< 0.001;
p
< 0.001, respectively). IL-6 and sIL-6R/IL-6 ratio at 24 h were independently associated with infarct size
β
5.4 (95% CI 3.3–7.5);
p
< 0.001,
β
− 4.0 (95% CI − 6.1 to − 1.9);
p
< 0.001, respectively. Higher levels of IL-6 at 24 h were associated with lower LVEF
β
− 4.2 (95% CI -6.7 to − 1.8);
p
= 0.001.
Conclusions
Higher IL-6 and lower sIL-6R/IL-6 ratio early after presentation with STEMI are indicative for larger infarct size and decreased cardiac function at 4 months.
Mixed cultivation of crops often results in increased production per unit land area, but the underlying mechanisms are poorly understood. Plants in intercrops grow differently from plants in single ...crops; however, no study has shown the association between plant plastic responses and the yield advantage. Here, we assessed the productivity of wheatâmaize intercropping as compared to sole wheat and sole maize, and the associated differences in wheat shoot and leaf traits. In two field experiments, intercrop wheat and maize were both grown in alternating strips consisting of six rows of wheat and two rows of maize. The traits of wheat plants in border rows of the strips were compared to the traits of plants in the inner rows as well as those in sole wheat. Leaf development, chlorophyll concentration and azimuth, as well as the final leaf and ear sizes, tiller dynamics of wheat and yield components of both crops were determined. The relative densities of wheat and maize in the intercrop were 0.33 and 0.67, respectively, but the corresponding relative yields compared to the respective monocultures were 0.46 for wheat and 0.77 for maize. Compared to wheat plants in the inner rows of the intercrop strips as well as in the monoculture, borderârow wheat plants in the intercrop strips had (a) more tillers owing to increased tiller production and survival, and thus more ears, (b) larger top leaves on the main stem and tillers, (c) higher chlorophyll concentration in leaves, (d) greater number of kernels per ear and (e) smaller thousandâgrain weight. Grain yield per metre row length of borderârow wheat was 141% higher than the sole wheat, and was 176% higher than the innerârow wheat. The results demonstrate the importance of plasticity in architectural traits for yield advantage in multispecies cropping systems.
•Current practice is unsustainable, leading to 1.6m/year groundwater decline.•44% yield reduction when switching to groundwater neutral cropping.•21–33% yield reduction for groundwater neutral with ...plastic film mulching in maize.•50% yield reduction when groundwater extraction no longer possible.•Increased frequency of complete crop failures when groundwater extraction no longer possible.
Groundwater levels in the North China Plain (NCP), the bread basket of China, have dropped more than one meter per year over the last 40 years, putting at risk the long term productivity of this region. Groundwater decline is most severe in the Alluvial Fans where our study site is located. Avoiding a foreseeable systems collapse requires region-wide changes in crop systems management, underpinned by sound environmental policies. Here, we explore the potential of crop system adaptation to remedy the excessive water use and quantify the likely yield penalties associated with more sustainable water use practices. Using simulations with the APSIM cropping systems model we explore production opportunities in an area within the NCP with intensive cropping and no access to irrigation from rivers. We estimate the attainable production levels for wheat and maize if agriculture were made groundwater neutral, through changes in crop sequence, irrigation practices and water conservation technologies (e.g. mulching with plastic film). Total grain production would drop by 44% compared to current practice if agriculture were made groundwater neutral. Water conservation by plastic film could limit this reduction to 21–33% but possible environmental impacts of plastic film need attention. This analysis facilitates a much needed debate on alternative agronomic practices and incentives through a quantitative comparison of adaptation options. Our biophysical analysis needs to be complemented with socio-economic considerations and discussions with all stakeholders. Similar analyses in other parts of the NCP are possible but require more accurate modelling of landscape hydrology and (towards the coast) risk of salt water intrusion.
Aim
Cereal-legume intercropping can result in yield gains compared to monocrops. We aim to identify the combination of crop traits and management practices that confer a yield advantage in strip ...intercropping.
Methods
We developed a novel, parameter-sparse process-based crop growth model (Minimalist Mixture Model, M
3
) that can simulate strip intercrops under well-watered but nitrogen limited growth conditions. It was calibrated and validated for spring wheat (
Triticum aestivum
) and spring faba bean (
Vicia faba
) grown as monocrops and intercrops, and used to identify the most suitable trait combinations in these intercrops via sensitivity analyses.
Results
The land equivalent ratio of intercrops was greater than one over a wide range of nitrogen fertilizer levels, but transgressive overyielding, with total yield in the intercrop greater than that of either sole crop, was only obtained at intermediate nitrogen applications. We ranked the local sensitivities of the individual yields of wheat and faba bean of the whole intercrop under various nitrogen input levels to various crop traits.
Conclusions
The total intercrop yield can be improved by selecting specific traits related to phenology of both species, as well as light use efficiency of faba bean and, under high nitrogen applications, of wheat. Changes in height-related crop traits affected individual yields of species in intercrops but not the total intercrop yield.
Objectives
Transcatheter aortic valve implantation (TAVI) is an important treatment option for patients with severe aortic stenosis. To improve patient selection, shared decision‐making is ...recommended to elicit patients' treatment expectations and goals. We assessed patients' expectations and goals before TAVI treatment and whether these were met after treatment. Additionally, we evaluated how meeting these goals aligned with quality of life and functional recovery.
Design
A mixed method study.
Setting
An academic medical center.
Participants
Seventy‐four patients undergoing TAVI between 2015 and 2017.
Measurements
Patients' expectations and goals were assessed qualitatively before treatment. Six to twelve months post procedure, quality of life was measured with the EuroQuol‐5D and any change in the number of dependencies in (instrumental) activities of daily living was assessed.
Results
Mean age of patients was 81.5 years, and 37.8% were male. Regaining the ability to engage in a specific hobby or activity was the most important treatment goal (33 patients, 54.1%), followed by reducing symptoms (19 patients 31.1%). 66.2% of patients stated that their treatment goal was met. Quality of life was higher in this group, as compared with patients who had not met their treatment goal. Twenty‐three patients (31.1%) showed functional improvement.
Conclusion
TAVI patients were quite capable of eliciting treatment goals and a majority stated, after treatment, that these had been met patients' experience of treatment benefits regarding these goals had poor alignment with functional outcomes. This raises questions regarding relevant outcome measurements in this population, and could aid in improving shared decision‐making and patient selection for TAVI.
Intercropping of wheat and cotton is practiced at a large scale in northern China, but the productivity of intercrops, compared to monoculture, and the productivity and growth patterns of different ...alternative intercropping patterns have not been quantitatively documented. In this study, four typical wheat–cotton intercropping patterns were examined as to their growth and productivity in field experiments over three growing seasons in Anyang, Henan Province, China. The systems varied in the number of wheat and cotton rows in the alternating strips of either crop, and were labeled accordingly as 3:1, 3:2, 4:2 and 6:2. Dry matter accumulation, yield, land equivalence ratio (LER) and lint quality were determined.
Grain yield of wheat, averaged over three seasons, ranged from 4600 to 5200
kg
ha
−1 in intercropping, corresponding to 70–79% of the yield in the monoculture (6550
kg
ha
−1). The 3:1 system gave the highest wheat yield (79% of monoculture), followed by the 6:2 (73%), 3:2 (70%) and 4:2 (70%) systems. Cotton lint yield, averaged over three seasons, ranged from 590 to 740
kg
ha
−1 in intercropping, corresponding to 54–69% of the yield in cotton monoculture (1085
kg
ha
−1). The 3:2 and 4:2 systems gave the highest lint yields (69% and 68% of monoculture, respectively), which was significantly lower than in monoculture but significantly higher than in the 3:1 (58%) and 6:2 (54%) systems. The land equivalent ratio was 1.39 in the 3:1, 3:2 and 4:2 systems, and significantly lower, 1.28, in the 6:2 system. All systems provide a substantial land use advantage.
Cotton growth patterns in monocultures and intercrops were characterized by fitting expolinear growth equations to periodic harvest data. Fitted parameters indicate a growth delay, compared to cotton monoculture, of 11.8
d in the 3:1 system, 6.3
d in the 3:2 system, 6.9
d in the 4:2 system and 5.6
d in the 6:2 system. Estimated growth rate during the linear growth phase was lowest in the 6:2 system (5.9
g
m
−2
d
−1), significantly greater in the 3:1 (7.0
g
m
−2
d
−1), 4:2 (7.7
g
m
−2
d
−1) and 3:2 (8.4
g
m
−2
d
−1) systems, and greatest, but not significantly different from 3:2 and 4:2 systems, in the monoculture (8.9
g
m
−2
d
−1). These results are interpreted in terms of the competitive effect of wheat during the seedling phase of cotton, which is strongest in the 3:1 system, causing a comparatively long growth delay, and the ability of the cotton leaf canopy to intercept radiation after wheat harvest, which is diminished in the 6:2 system due to the large distance between cotton rows, resulting in a comparatively low rate of linear growth.
Effects of intercropping on the quality of cotton were minor and mostly below detection threshold.
Pine wood nematode (PWN), Bursaphelenchus xylophilus, is a threat for pine species (Pinus spp.) throughout the world. The nematode is native to North America, and invaded Japan, China, Korea, and ...Taiwan, and more recently Portugal and Spain. PWN enters new areas through trade in wood products. Once established, eradication is not practically feasible. Therefore, preventing entry of PWN into new areas is crucial. Entry risk analysis can assist in targeting management to reduce the probability of entry. Assessing the entry of PWN is challenging due to the complexity of the wood trade and the wood processing chain. In this paper, we develop a pathway model that describes the wood trade and wood processing chain to determine the structure of the entry process. We consider entry of PWN through imported coniferous wood from China, a possible origin of Portuguese populations, to Europe. We show that exposure increased over years due to an increase in imports of sawn wood. From 2000 to 2012, Europe received an estimated 84 PWN propagules from China, 88% of which arose from imported sawn wood and 12% from round wood. The region in Portugal where the PWN was first reported is among those with the highest PWN transfer per unit of imported wood due to a high host cover and vector activity. An estimated 62% of PWN is expected to enter in countries where PWN is not expected to cause the wilt of pine trees because of low summer temperatures (e.g., Belgium, Sweden, Norway). In these countries, PWN is not easily detected, and such countries can thus serve as potential reservoirs of PWN. The model identifies ports and regions with high exposure, which helps targeting monitoring and surveillance, even in areas where wilt disease is not expected to occur. In addition, we show that exposure is most efficiently reduced by additional treatments in the country of origin, and/or import wood from PWN-free zones. Pathway modelling assists plant health managers in analyzing risks along the pathway and planning measures for enhancing biosecurity.
In China, a large acreage of cultivated land is devoted to relay intercropping of winter wheat and cotton. Wheat is sown in strips with interspersed bare soil in October and harvested in June of the ...next year, while cotton is sown in the interspersed paths in the wheat crop in April and harvested before the next wheat sowing in October. This paper addresses the question how strip width and number of plant rows per strip of wheat or cotton affect light interception (LI) and light use efficiency (LUE) of both component crops.
Field experiments were carried out in three consecutive years: 2002, 2003 and 2004. Light interception and productivity were estimated in monocultures of wheat and cotton and four intercropping designs differing in strip and path width as well as number of rows per strip. The intercrop systems were identified by the number of rows per strip of wheat and cotton, respectively, as 3:1, 3:2, 4:2 and 6:2. Total light interception over a season was calculated from LAI measurements, using a model for light interception in a row crop. The spatial distribution and diurnal course of light in intercrops were also measured with sensors.
Wheat monocrops intercepted 618
MJ
m
−2 photosynthetically active radiation (PAR) from 18 March to harvest in 2002, 337
MJ
m
−2 from 29 April to harvest in 2003, and 457
MJ
m
−2 from 13 April to harvest in 2004. Averaged over 3 years, wheat in the four intercrops (3:1, 3:2, 4:2 and 6:2, respectively) intercepted 83, 71, 73 and 75% as much PAR as the sole wheat. From sowing to harvest, cotton monocrops intercepted 491
MJ
m
−2 PAR in 2002, 426
MJ
m
−2 in 2003, and 415
MJ
m
−2 in 2004. Cotton in the four intercrops (3:1, 3:2, 4:2 and 6:2, respectively) intercepted 73, 93, 86 and 67% as much PAR as the sole cotton. LUE of wheat was 2.12
±
0.14
g
total
dry
matter
MJ
−1 PAR during the reproductive period, while that of cotton was 1.33
±
0.02
g
dry
matter
MJ
−1 PAR over the whole growing period. No differences in LUE of wheat or cotton were found between systems.
The analysis indicates that the high productivity of intercrops, compared to monocultures, can be fully explained by an increase in accumulated light interception per unit cultivated area. The component crops are thus complementary in their interception of light over space and time. The model results indicate that light interception can be modified by choice of the number of crop rows per strip and strip width. The best distribution of light is attained in systems with narrow strips, a high proportion of border rows, and high planting densities of cotton. Suggestions for system improvement are given.
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