Farming intensity indirectly reduces crop yield through negative effects on agrobiodiversity and key ecological functions

RESUMO – O milho é uma planta monoica, e a geração de novos híbridos exige a remoção do pendão das plantas.Sabe-se que a remoção do pendão possui efeito negativo na produtividade da cultura. Contudo, a aplicação de Ncomplementar, via foliar, poderia minimizar essas perdas. Assim, o objetivo deste estudo foi avaliar como o Ncomplementar afeta a produtividade e os componentes de rendimento da cultura do milho submetida ao despendoamento.O estudo foi conduzido em delineamento de blocos casualizados em esquema fatorial 2 x 3 x 5, sendo duas safras(2014/15 e 2015/16), três momentos de despendoamento (sem despondoamento, arranquio de 2-3 folhas e arranquiode 4-5 folhas antes do pendoamento) e cinco doses de N complementar (0, 5, 10, 15, 20 L ha-1) aplicadas no estádio depré-pendoamento (VT). Não foi verificada interação N complementar X despendoamento para nenhuma das variáveisestudadas. A menor produtividade foi verificada no despendoamento de 4-5 folhas. A aplicação de N complementaraumentou a produtividade da cultura do milho, e a aplicação de 11,5 L ha-1 incrementou a produtividade em 448 kgha-1. O despendoamento diminuiu a produtividade da cultura do milho, quanto mais precoce o despendoamento, maisnegativo é o efeito na produtividade.Palavras-chave: Melhoramento genético, N complementar, pendoamento, produção de sementes, Zea mays.FOLIAR APPLICATION OF COMPLEMENTARY NITROGEN,IN MAIZE SUBJECTED TO DETASSELINGABSTRACT – Maize is a monoic plant and the generation of new hybrids requires the removal of the tassel from theplants, which has a negative effect on crop yield. However, the use of complementary leaf nitrogen (N) fertilization,could minimize the yield losses. Therefore, the objective of this study was to evaluate the effect os the application ofcomplementary N affects on yield of the maize crop subjected to detasseling. The study was carried out in a randomizedcomplete block design, with a 2 x 3 x 5 factorial scheme and four replications. Two growing seasons (2014/15 and2015/16), three detasseling moments (without detasseling, detasseling of 2-3 leaves, and detasseling of 4-5 leaves)and five doses of complementary N (0, 5, 10, 15, 20 L ha-1) applied at the VT stage. There was no interaction betweencomplementary N and detasseling for any of the variables studied. The lowest yield was verified with the detasselingof 4-5 leaves. The application of complementary N showed a positive effect on maize yield, and the application of 11.5L ha-1 of complementary N provided yield increase of 448 kg ha-1. The detasseling technique had negative effects onmaize crop yield, the earlier is the detasseling, the more negative is the effect on yield.Keywords: Genetic improvement, Seed production, tasseling, Zea mays.

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Genetic Diversity Assessment and Marker-Assisted Selection in Crops

Genes ◽

10.3390/genes11121481 ◽

2020 ◽

Vol 11 (12) ◽

pp. 1481

Author(s):

Francesco Mercati ◽

Francesco Sunseri

Keyword(s):

Genetic Diversity ◽

Global Warming ◽

Reproductive Success ◽

Crop Yield ◽

Marker Assisted Selection ◽

Climate Changes ◽

Negative Effects ◽

Diversity Assessment ◽

Earth’S Climate

Global warming is negatively impacting on crop yield and Earth’s climate changes can bring possible negative effects on the growth and reproductive success of crops [...]

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Reinspecting the Climate-Crop Yields Relationship at a Finer Scale and the Climate Damage Evaluation: Evidence from China

Complexity ◽

10.1155/2020/9424327 ◽

2020 ◽

Vol 2020 ◽

pp. 1-8

Author(s):

Yongbin Zhu ◽

Yajuan Shi ◽

Changxin Liu ◽

Bing Lyu ◽

Zhenbo Wang

Keyword(s):

Winter Wheat ◽

Crop Yield ◽

Spring Wheat ◽

Crop Yields ◽

Growth Stages ◽

Climate Variables ◽

Negative Effects ◽

Summer Maize ◽

Climate Effects ◽

Positive Effects

This paper reinvestigated the climate-crop yield relationship with the statistical model at crops’ growing stage scale. Compared to previous studies, our model introduced monthly climate variables in the production function of crops, which enables separating the yield changes induced by climate change and those caused by inputs variation and technique progress, as well as examining different climate effects during each growing stage of crops. By applying the fixed effect regression model with province-level panel data of crop yields, agricultural inputs, and the monthly climate variables of temperature and precipitation from 1985 to 2015, we found that the effects of temperature generally are negative and those of precipitation generally are positive, but they vary among different growth stages for each crop. Specifically, GDDs (i.e., growing degree days) have negative effects on spring maize’s yield except for the sowing and ripening stages; the effects of precipitation are negative in September for summer maize. Precipitation in December and the next April is significantly harmful to the yield of winter wheat; while, for the spring wheat, GDDs have positive effects during April and May, and precipitation has negative effects during the ripening period. In addition, we computed climate-induced losses based on the climate-crop yield relationship, which demonstrated a strong tendency for increasing yield losses for all crops, with large interannual fluctuations. Comparatively, the long-term climate effects on yields of spring maize, summer maize, and spring wheat are more noticeable than those of winter wheat.

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On the Strategies of Optimizing the Landscape of the Urban Green Space: Based on Ecological Security

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.357-360.2014 ◽

2013 ◽

Vol 357-360 ◽

pp. 2014-2017

Author(s):

Feng Quan Ji ◽

Jin Long Chu

Keyword(s):

Sustainable Development ◽

Green Space ◽

Urban Ecosystem ◽

Urban Green Space ◽

Ecological Security ◽

Negative Effects ◽

Ecological Functions ◽

Protection Measures ◽

The Sustainable Development ◽

Urban Green

The design and planning of the urban green landscape is manipulated to attain the integrity and sustainability of the process of landscaping the urban green space. Based on the analysis of the problems in landscaping the urban green space, this study attempts to explore the strategies of optimizing the landscape of the urban green space so as to improve the ecological functions of the eco-city, better the layout of the urban planning, and increase the green quantity. Appropriate regulation and protection measures have been adopted to prevent the negative effects in planning the urban green space, guarantee the safety of the urban ecosystem, and maintain the sustainable development of the vegetation sources of the gardens and green lands.

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PATRONES DEL PAISAJE Y ESCENARIOS DE RESTAURACIÓN EN COLOMBIA: ACERCANDO ESCALAS

Acta Biológica Colombiana ◽

10.15446/abc.v21n1supl.50848 ◽

2016 ◽

Vol 21 (1Supl) ◽

pp. 229-239 ◽

Cited By ~ 3

Author(s):

Dolors Armenteras ◽

Orlando Vargas

Keyword(s):

Land Use ◽

Ecological Impacts ◽

Negative Effects ◽

Ecological Functions ◽

Complex Interactions ◽

Landscape Processes ◽

Toma De Decisiones ◽

Landscape Scales ◽

Natural Dynamics ◽

Land Use And Management

El paisaje, entendido como un mosaico heterogéneo, es una unidad donde interactúan ecosistemas, especies y el hombre con el uso que este último hace del mismo. El paisaje es el resultado de complejas interacciones, no solo producto de dinámicas naturales sino del balance de la oferta y la demanda de la sociedad ante la preferencia por los recursos que este ofrece. Este equilibrio causa impactos ecológicos sobre los ecosistemas y la diversidad de organismos que ocupan los paisajes. El uso y manejo del territorio aumenta la heterogeneidad espacial, en muchos casos a través de la pérdida y fragmentación de hábitat. Estos procesos traen alteraciones sobre el funcionamiento de los ecosistemas, afectando funciones y procesos ecológicos que dependen del flujo de energía y materiales a través de paisajes. El objetivo de este trabajo es avanzar en la comprensión de los orígenes de la heterogeneidad resultante de estas dinámicas, para mitigar sus efectos y entender cómo planificar y manejar los paisajes. Restaurar, rehabilitar y recuperar ecosistemas son estrategias para asegurar la conservación, sostenibilidad y en algunos casos la recuperación de servicios ecosistémicos. En ocasiones las escalas de paisaje y aquellas a las cuales se realizan actividades de restauración se encuentran alejadas en la práctica. Este artículo presenta una revisión de conceptos claves en ecología del paisaje y de restauración, acercando escalas intrínsecas de los fenómenos y de toma de decisiones para el desarrollo de escenarios de manejo y restauración en Colombia. AbstractThe landscape, understood as a heterogeneous mosaic is a unit where ecosystems, species and man’s land use interact. It is the result of complex interactions, not only as a result of natural dynamics but also the balance created between the supply and the demand of society driven by the preference for certain resources. This balance causes ecological impacts both on ecosystems and the diversity of organisms that occupy the landscape. Land use and management tend to increase the spatial heterogeneity in many cases through landscape processes such as the habitat loss and fragmentation. These processes bring alterations in the functioning of ecosystems, affecting the ecological functions and those processes that depend on the flow of energy and materials through landscapes. The objective of this paper is to advance in the understanding of the origins of such heterogeneity in order to mitigate its negative effects and to better plan and manage landscapes. All restore, rehabilitate and ecosystems recovery, are strategies toensure the conservation, sustainability, and in some cases recovery of ecosystem services. Often landscape scales and those to whichrestoration activities are carried away are very distant in practice. This article presents a reflection carried out within the frameworkof the Chair Mutis 2015, it presents an overview of the key concepts in landscape ecology and restoration and an attempt to bridgeintrinsic and decision making scales to advance in the development of restoration scenarios in Colombia starting from the landscape scale but integrating local knowledge and actions.

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Manipulating Crop Row Orientation to Suppress Weeds and Increase Crop Yield

Weed Science ◽

10.1614/ws-09-094.1 ◽

2010 ◽

Vol 58 (2) ◽

pp. 174-178 ◽

Cited By ~ 37

Author(s):

Catherine P. D. Borger ◽

Abul Hashem ◽

Shahab Pathan

Keyword(s):

Weed Control ◽

Crop Yield ◽

Cropping System ◽

Farming System ◽

Control Technique ◽

Negative Effects ◽

Weed Biomass ◽

Weed Growth ◽

Field Peas ◽

East West

Crop rows oriented at a right angle to sunlight direction (i.e., east–west within the winter cropping system in Western Australia) may suppress weed growth through greater shading of weeds in the interrow spaces. This was investigated in the districts of Merredin and Beverley, Western Australian (latitudes of 31° and 32°S) from 2002 to 2005 (four trials). Winter grain crops (wheat, barley, canola, lupines, and field peas) were sown in an east–west or north–south orientation. Within wheat and barley crops oriented east–west, weed biomass (averaged throughout all trials) was reduced by 51 and 37%, and grain yield increased by 24 and 26% (compared with crops oriented north–south). This reduction in weed biomass and increase in crop yield likely resulted from the increased light (photosynthetically active radiation) interception by crops oriented east–west (i.e., light interception by the crop canopy as opposed to the weed canopy was 28 and 18% greater in wheat and barley crops oriented east–west, compared with north–south crops). There was no consistent effect of crop row orientation in the canola, field pea, and lupine crops. It appears that manipulation of crop row orientation in wheat and barley is a useful weed-control technique that has few negative effects on the farming system (i.e., does not cost anything to implement and is more environmentally friendly than chemical weed control).

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Does Neem trigger the same response as Ivermectin? Dung beetle behaviour and physiology

10.7287/peerj.preprints.26770 ◽

2018 ◽

Author(s):

Agnis Souza ◽

Ronara Ferreira-Châline ◽

Nicolas Châline ◽

Vanesca Korasaki ◽

Wallace Beiroz ◽

...

Keyword(s):

Body Fat ◽

Physiological Stress ◽

Soxhlet Extraction ◽

Dung Beetle ◽

Fat Content ◽

Dung Beetles ◽

Negative Effects ◽

Ecological Functions ◽

Veterinary Pharmaceutical ◽

Body Fat Content

Potential negative effects of the synthetic veterinary pharmaceutical, Ivermectin, on non-target fauna have generated a search for less-toxic alternatives. Thus, Neem plant extract (Azadirachta indica A. Juss) has been used as a natural alternative to replace Ivermectin worldwide. However, little is known about the effects of this natural veterinary pharmaceutical’s residues on the behaviour and physiology of adult dung beetles (Coleoptera: Scarabaeinae), which use livestock dung as a feeding and nesting resource. To understand such effects, we performed a non-choice experiment using Dichotomius nisus Oliver, 1798. We evaluated effects of Neem and Ivermectin residues on the ecological functions of dung burial and soil bioturbation performed by dung beetles. Additionally, we performed Soxhlet extraction of dung beetle body fat content to evaluate physiological stress in response to ingestion of Ivermectin or Neem. Our results showed that D. nisus do not alter their behaviour in the presence of Neem and Ivermectin residues in dung when contrasted with the control after 48 hours. However, individuals feeding on dung with Ivermectin residues for a period of twenty days had 5% more body fat content than those from control and Neem treatments. Our findings provide the first evidence that Neem can be a less toxic alternative to non-target fauna than Ivermectin.

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MAIN WAYS TO OPTIMIZE THE CULTIVATED PLANT PRODUCTIVITY ON LAND LIABLE TO DEGRADATION

Land Degradation and Desertification: Problems of Sustainable Land Management and Adaptation ◽

10.29003/m1684.978-5-317-06490-7/96-100 ◽

2020 ◽

Author(s):

K. Tsivka ◽

Aleksandr Popov ◽

M. Hafez ◽

M. Rashad ◽

Natalya Kovaleva

Keyword(s):

Crop Yield ◽

Global Climate ◽

Plant Productivity ◽

Climatic Conditions ◽

Cultivated Plants ◽

Negative Effects ◽

Additional Increase ◽

Physical Chemical ◽

Productive Process ◽

Cultivated Plant

The purpose of this publication was to describe the main ways to optimize the productive process of cultivated plants on land subject to degradation. There are three kinds of correction: physical, chemical and biological. Biological correction is new way to optimize the production process of crops, which is a set of methods of directive effect on plant biology. The key points and essence of biological correction are considered. One of the most effective and economically justified methods of biological correction of plant productivity is non-root treatment of crops by humic substances (HSs) solutions, especially those containing essential macro-and microelements. Such treatments can reduce the negative effects of projected global climate change (excessive UV-B radiation, drought, etc.) on agricultural plants. As confirmation, the results of a field experiment conducted in the arid territory of Egypt are presented. Means of biological correction, such as: Azospirillum sp., vermicompost and HSs solutions (without and with trace elements) were very effective, they increased (more than 2.5 times!) the yield of wheat grain. Thus, to obtain a consistently high crop yield on land subject to degradation, especially in changing climatic conditions, it is necessary to apply three kinds of correction: physical, chemical and biological. Both physical correction and chemical one create the necessary conditions for the growth and development of plants, and biological correction "forces" plants to show their reserve functions, contributing to an additional increase in crop yield.

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Effects of Nanomaterials on Plant Growth at Molecular Level

Current Materials Science ◽

10.2174/2666145414666210521213759 ◽

2021 ◽

Vol 14 ◽

Author(s):

Yuxin Li ◽

Yukui Rui ◽

Bo Huang ◽

Mengyuan Liu ◽

Adeel Muhammad ◽

...

Keyword(s):

Cell Wall ◽

Plant Growth ◽

Crop Yield ◽

Molecular Level ◽

Negative Effects ◽

Stimulate Plant Growth ◽

Carbon Based Nanomaterials ◽

The Impact ◽

Positive Effect ◽

Increase Crop Yield

Abstract: Nanomaterials are widely used in all walks of life, bringing great changes to our life and production. In addition, nanomaterials have also been used in agriculture. The most common ones are carbon-based nanomaterials and TiO2 nanoparticles, which can stimulate plant growth and increase crop yield. However, not all nanomaterials have a positive effect on plant growth. Therefore, it is necessary to understand the influence of nanomaterials on plants after entering the environment. Nanomaterials can be inhaled directly or through endocytosis. Some nanomaterials will become the corresponding ion state to enter the plant, while some larger nanomaterials will block cell wall channels or adsorb on the surface of plants. Nanoparticles (NPs) enter the plant can produce positive or negative effects on the plant's genes, proteins. This paper discusses the impact of nanomaterials on plant growth and the molecular level.

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Micromorphological and Chemical Approaches to Understand Changes in Ecological Functions of Metal-Impacted Soils under Various Land Uses

Applied and Environmental Soil Science ◽

10.1155/2011/521329 ◽

2011 ◽

Vol 2011 ◽

pp. 1-12 ◽

Cited By ~ 1

Author(s):

J. A. Acosta ◽

S. Martinez-Martinez ◽

A. Faz ◽

J. M. Van Mourik ◽

J. M. Arocena

Keyword(s):

Soil Fauna ◽

Total Concentration ◽

Industrial Site ◽

Land Uses ◽

Potentially Toxic Metals ◽

Negative Effects ◽

Ecological Functions ◽

Ecological Functions Of Soils ◽

Solid Phases ◽

Mn Oxides

We investigated the changes in faunal activities as measures of the ecological functions of soils impacted by potentially toxic metals (PTMs) under urban, industrial, agricultural, and natural uses. Concentrations and distributions of Zn, Cd, Pb, Cu, Mn, and Fe were estimated by sequential chemical extractions, while relicts and present faunal activities were studied by micromorphological analyses. Urban and natural lands were contaminated with Pb, Cd, and Zn. Microarthropods and fungi are observed to be active in the litter decomposition in natural, agricultural and urban lands which indicates that total concentration of PTMs in soils is not a good indicator to evaluate the limitations of PTMs to fauna activity. Metals immobilization on carbonates and Fe/Mn oxides, and fertilizations reduced the negative effects of metals on faunal activity. Micromorphological analyses showed the impacts of metal on soil ecological functions in industrial site, where the surface soils are devoid of any evidence of faunal activity; likely due to high proportion of Pb and Zn in organic components. Therefore, the impacts of metals in soil fauna activities, hence ecological functions of soils, are best evaluated by the knowledge of metal partitioning on solid phases in combination with observations of fauna activities using micromorphological techniques.

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