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| Registros recuperados: 51 | |
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| Doole, Graeme J.. |
| Many important problems in agricultural and natural resource economics concern an intertemporal choice between alternate dynamic systems. This significance has motivated a theoretical literature generalizing the necessary conditions of Optimal Control Theory to multiple-phase problems. However, gaining detailed insight into their practical management is difficult because general numerical solution methods are not available. This paper resolves this deficiency through the development of a flexible and efficient computational algorithm based on a set of necessary conditions derived for finite-time, multiple-phase systems. Its effectiveness is demonstrated in an application to a nontrivial crop rotation problem. |
| Tipo: Journal Article |
Palavras-chave: Crop management; Multiple-phase systems; Optimal control; Crop Production/Industries; Resource /Energy Economics and Policy. |
| Ano: 2009 |
URL: http://purl.umn.edu/50082 |
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| Mussei, Ahaz; Mwanga, Judicate; Mwangi, Wilfred; Verkuijl, Hugo; Mongi, Rose; Elanga, Anthony. |
| This study was conducted to gain an understanding of how small-scale farmers in Mbeya District have adopted improved wheat technologies promoted by the wheat research program at MARTI-Uyole. The specific objectives were to assess farmers’ wheat management practices, determine the technical and socioeconomic factors affecting the adoption of improved wheat technologies, and draw implications for research, extension, and policy. A purposive multistage sampling procedure was used to select 202 farmers, 160 from Tembela Division and 42 from Isangati Division, which are two important wheat-growing areas in Mbeya District. Primary data were collected using structured questionnaires and supplemented by secondary information obtained from MARTI-Uyole. Juhudi was... |
| Tipo: Report |
Palavras-chave: Tanzania; Wheats; Varieties; Innovation adoption; Technology transfer; Economic indicators; Socioeconomic environment; Plant breeding methods; Research programs; Crop management; Fertilizer application; Food production; Small farms; Highlands; Crop Production/Industries; E14; E30. |
| Ano: 2001 |
URL: http://purl.umn.edu/56190 |
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| GASPAROTTO, L.; PEREIRA, J. C. R.; PEREIRA, M. C. N.; COSTA, M. M. da. |
| A Sigatoka negra, causada pelo fungo Mycosphaerella fijiensis (fase anamórfica: Paracercospora fijiensis (Morelet) Deighton, é a doença mais grave da bananeira, causando perdas de 100% da produção, quando não se efetua o controle. Os fungicidas trifloxistrobin, difenoconazole e propiconazole, foram eficientes no controle da Sigatoka negra, aplicados a intervalos regulares de 14 dias. |
| Tipo: Folhetos |
Palavras-chave: Mal de sigatoka; Brasil; Amazonas; Manaus; Plant diseases; Chemical controls; Banana; Cercosporiose; Controle Químico; Doença de Planta; Fungicida; Fungo; Manejo; Musa Acuminata; Crop management; Fungi; Fungicides. |
| Ano: 2000 |
URL: http://www.infoteca.cnptia.embrapa.br/infoteca/handle/doc/668638 |
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| BARRETO, J. F.; DIAS, M. C.; XAVIER, J. J. B. N.; MARTINS, G. C.; FIGUEIREDO, E. A.. |
| Visando disponibilizar variedades melhoradas e adaptadas as condicoes ambientais do Amazonas, a Embrapa Amazonia Ocidental em conjunto com a Embrapa Milho e Sorgo, apos varias etapas de selecao, com enfase maior para as varzeas, em solos classificados como gley pouco humido e caracterizados como de alta fertilidade natural e, tambem de maior concentracao de produtores da cultura. Estas variedades selecionadas e adaptadas as condicoes de varzea, se bem exploradas, contribuirao substancialmente para o aumento da producao de milho no Estado. |
| Tipo: Folders |
Palavras-chave: Cultivo; Brasil; Amazonas; Humaita; Maize; Milho; Variedade; Zea Mays; Crop management; Varieties. |
| Ano: 2000 |
URL: http://www.infoteca.cnptia.embrapa.br/infoteca/handle/doc/670183 |
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| SCHOENINGER,Karine; SOUZA,Jorge L.P.; KRUG,Cristiane; OLIVEIRA,Marcio L.. |
| ABSTRACT We surveyed parasitoid wasps (Hymenoptera) in two guarana plantations in the central Brazilian Amazon (one conventionally, and one organically managed), as well as in adjacent forest and edge areas between crop and forest. We evaluated differences between management systems in parasitoid diversity and abundance, and assessed the importance of the surrounding matrix as a source of parasitoid wasps for guarana cultivation. Parasitoid wasp richness, abundance and taxonomic composition (at family level) were compared between plantations, and among habitats within plantations. Wasps were sampled using Malaise and Moericke traps. A total of 25,951 parasitoid wasps (10,828 in the conventional, and 15,123 in the organic crop area) were collected, and were... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Agroecosystem; Chalcidoidea; Crop management; Encyrtidae; Natural enemies. |
| Ano: 2019 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0044-59672019000400283 |
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| LANZA,T.R.; MACHADO,A.F.L.; MARTELLETO,L.A.P.. |
| ABSTRACT The objective is to evaluate the effects of plant density in banana crops against weed suppression. Six treatments were used: 1,200 (3.33 x 2.5 m), 1,600 (2.5 x 2.5 m), 2,000 (2.0 x 2.5 m), 2,400 (1.67 x 2.5 m), 2,800 (1.43 x 2.5 m) and 3,200 (1.25 x 2.5 m) banana plants per hectare, arranged in an experimental design of randomized blocks with four replications. The phytosociological study of weed communities was carried out one month after transplanting and then every 90 days, totaling six samples in 16 months of cultivation, always those being held 15 days after mowing. With the data of dry mass and number of individuals per species Relative density (De.R) Relative frequency (Fr.R) Relative dominance (Do.R), importance value value (IVI) of weed... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Banana crop; Phytosociology; Crop management. |
| Ano: 2017 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-83582017000100252 |
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| Studnicki,Marcin; Mądry,Wiesław; Derejko,Adriana; Noras,Kinga; Wójcik-Gront,Elżbieta. |
| Cultivars have to be evaluated under different crop management systems across agro-ecosystems and years using multi-environment trials (MET) before releasing them to the market. Frequently, data collected in METs are arranged according to cultivar (G), management (M), location, (L) and year (Y) combinations in a four-way G x M x L x Y data table that is highly unbalanced for cultivars across locations and time. Therefore, we present the restricted maximum likelihood method (REML) for linear mixed models (LMM) with a factor analytic variance-covariance matrix for assessing cultivar adaptation to crop management systems and environments based on unbalanced datasets. Such a multi-environmental trial system has been in operation in Poland for winter wheat... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Crop management; Restricted maximum likelihood methods; Unbalanced data; Winter wheat. |
| Ano: 2015 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0103-90162015000500411 |
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| Viais Neto,Daniel dos S.; Cremasco,Camila P.; Bordin,Deyver; Putti,Fernando F.; Silva Junior,Josué F.; Gabriel Filho,Luís R. A.. |
| ABSTRACT It was used statistical techniques for the evaluation of agricultural experiments, but there are mathematical theories that allow finer adjustments, highlighting among them, the fuzzy logic. The objective of the study was characterizing a method of fuzzy modeling from an agronomic experiment. For this study it was used data from an experiment conducted at the School of Agriculture of São Paulo State University (UNESP) in Botucatu-SP. The system input variables based in fuzzy rules were soil water tension and doses of water salinity, being defined three fuzzy sets. The output variables was elected from the biometric and productivity analysis that showed statistically significant differences, namely, plant height, stem diameter, leaf area, green... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Fuzzy logic; Drought; Salt stress; Crop management. |
| Ano: 2019 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-69162019000300294 |
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| A busca por cultivos de café bem manejados do ponto de vista sanitário é questão essencial. E, em se tratando do ambiente Amazônico, as condições edafoclimáticas (temperatura e pluviosidade média elevadas) constituem-se grande desafio aos cafeicultores e técnicos envolvidos no manejo da cultura, diferindo?se significativamente das demais regiões produtoras Nesse sentido, torna-se premente a correta identificação dos problemas fitossanitários associados à cultura, de forma a facilitar as decisões referentes às necessidades de qual, quando e como realizar o manejo. Objetiva-se assim auxiliar os produtores, técnicos e demais interessados na cultura do cafeeiro, como uma fonte de consulta rápida e portátil, auxiliando a tomada de decisões, por meio de... |
| Tipo: Livros |
Palavras-chave: Coffee plant; Cafezal; Doença de Planta; Praga de Planta; Identificação; Manejo; Pratica Cultural; Plant diseases and disorders; Plant pests; Pathogen identification; Plant cultural practices; Crop management; Amazonia. |
| Ano: 2020 |
URL: http://www.infoteca.cnptia.embrapa.br/infoteca/handle/doc/1125364 |
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| Carvalho,Saul Jorge Pinto de; Nicolai,Marcelo; Ferreira,Renato Rodrigues; Figueira,Antonio Vargas de Oliveira; Christoffoleti,Pedro Jacob. |
| Herbicide selectivity is an agricultural technology largely exploited in chemical strategies of weed control. The joint action of several protection mechanisms avoids phytotoxicity from herbicide treatment, maintaining the level of agronomically accepted damage to a minimum, or even totally avoiding them. The major mechanism of herbicide selectivity derives from the differential metabolism between weed and crop plant species, with weeds presenting a limited ability to perform it under agronomically recommended conditions. In this case, phytotoxicity can be interpreted as an overcoming of the maximum protection capacity offered by the mechanisms of selectivity, or when considering metabolism as the main factor, the overcoming of the inherent plant ability... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Phytotoxicity; Injuries; Yield; Experimental design; Crop management. |
| Ano: 2009 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0103-90162009000100020 |
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| Registros recuperados: 51 | |
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