57 research outputs found
Impact of harvest residues, fertilisers and N-fixing plants on growth and nutritional status of young Eucalyptus globulus plantations under Mediterranean conditions
Growth and nutritional status of young plants
of Eucalyptus were assessed in a field trial, under different
scenarios of harvest residue management and nutrient
availability. Treatments were as follows: incorporation of
harvest residues into the soil by harrowing (I); I with N
fertiliser application (IF); I with leguminous, Lupinus
luteus L., seeding (IL); removal of harvest residues (R); R
with N fertiliser application (RF); R with leguminous
seeding (RL); distribution of harvest residues on the soil
surface (S); S with N fertiliser application (SF). Treatments
were replicated four times in four blocks with a fully
randomised design. Tree growth (height and diameter at
breast height) was measured and understory biomass
destructively recorded. Tree nutritional status was assessed
by foliar analysis (N, Ca, Mg, P, K and leaf area). Significant
differences in growth between I, R and S treatments
were only detected at early stage. Intercropping with
Lupinus decreased tree growth during the early phase, but
after 5 years growth was similar to that measured in the I
and R treatments. Application of fertiliser enhanced tree
growth especially when harvest residues were retained on
the soil surface. Combining incorporation of harvest residues
with fertiliser application (IF) was the best option to
increase tree growth, which was significantly greater than
in the R and S. Initially, leaf N was positively affected by
the leguminous (RL and IL), but, after the first fertiliser
application (1 year after planting), greater N was observed in the IF, RF and SF, the difference decreasing gradually
over the following year
Studies on the association of the Quercus suber decline disease with Phytophthora cinnamomi in Portugal
En Portugal, la enfermedad de la “seca” se ha
descrito en los Quercus de hoja perenne (Quercus
suber L. and Q.ilex subsp. rotundifolia Lam.) desde
el final del siglo XIX. La mortalidad de estas
especies afecta, particularmente las regiones centrales
y meridionales del país, siendo uno de los problemas
forestales más graves. Phytophthora cinnamomi
Rands es el principal patógeno responsable de la
mortalidad de alcornoques y encinas en Portugal. Se
han desarrollado varios estudios teniendo como
objetivo una mejor comprensión del efecto de la
acción de P. cinnamomi en el decaimiento de los
Quercus.
El actual trabajo describe resultados preliminares
de algunos de estos estudios.___________________________________In Portugal, the decline disease has been described
in evergreen oaks (Quercus suber L. and Q.ilex
subsp. rotundifolia Lam.) since the end of the 19th
century. The mortality of these species affects,
particularly the central and southern regions of the
country, being one of the most severe forest
problems. Phytophthora cinnamomi Rands is the
main pathogen responsible for the cork and holm
oak mortality in Portugal. Several studies have
been developed aiming at a better understanding of
the effect of the P. cinnamomi action on the cork
oak trees decline.
The present work describes preliminary results of
some of these studies
Caracterização da cadeia produtiva de brássicas no Brasil
Brassica crops worldwide provide the greatest diversity of products used by man derived from a single genus. Collectively, leafy, flower and root vegetables can be eaten fresh, cooked and processed. The production of these vegetables in Brazil has been growing exponentially in the last decades, due to its economic importance, with major production volumes in several states and a quick monetary return for growers in areas considered of small acreage. With expansion, a number of aspects, including demands for quality and safety of these foods introduce themselves, strictly attached to the forms of production, logistics and their appearance. To meet the challenges and list the trends within the activities of different agents, a multiple case study was held in the states of Amazon, Minas Gerais, Paraná and Rio de Janeiro. Altogether, 55 stakeholders were interviewed, along with the compilation of different sources of data to characterize this productive chain. Changes in the scenario are imperative in order to maintain the activity of overcoming years, being related to cultivars adaptation, plant health, productions costs and difficulties during the establishment of crops. To overcome these adversities, a collective effort in terms of organization, technology transfer and R&D from official and private agents, technical assistance, and regional sanitary inspection is imperative, aiming, especially, in actions regarding themes like protected cultivation, mechanization/automation and adding value to products by processing and packaging, listed by stakeholders as priority. © 2019, Sociedade de Olericultura do Brasil. All rights reserved
Morphological Interpretation of Reflectance Spectrum (MIRS) using libraries looking towards soil classification
Cor do solo: uma abordagem da forma convencional de obtenção em oposição à automatização do método para fins de classificação de solos
Efeito da severidade de oídio e crestamento foliar de cercospora na produtividade da cultura da soja
Avaliação do desempenho e do rendimento de carcaça de quatro linhagens de frangos de corte em dois sistemas de criação
Comparison between detailed digital and conventional soil maps of an area with complex geology
Spatial variability of leaf wetness duration in cotton, coffee and banana crop canopies
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