201 research outputs found
Thinning kiwifruit
Durante la temporada 1999-2000 un
lote de plantas de kiwi (Actinidia deliciosa
(A. Chev.) C. F. Liang et A. R. Ferguson var.
deliciosa cv Hayward) fue sometido a tres
intensidades de raleo: 30, 40 y 50 frutos/m2
a los 19 días post-floración. Se evaluó la
calidad de los frutos desarrollados en 3 tipos
de ramificación lateral: fuerte, medio y
débil. Se registró la evolución del crecimiento
del fruto. Se determinó peso, contenido
de sólidos solubles, firmeza de la pulpa y
pH del jugo al momento de cosecha.
• Las intensidades de raleo de 30, 40 y
50 frutos/m2 produjeron frutos de peso promedio
125, 121 y 113 g respectivamente.
En los tres casos se superó el peso mínimo
exigido para exportación.
• Los laterales de tipo débil produjeron los frutos
de menor peso y más blandos a cosecha.
No se encontraron diferencias entre laterales
en contenido de sólidos solubles y pH.
• Los raleos intensos favorecieron la tasa
de crecimiento del fruto pero la mayor intensidad
de raleo (30 frutos/m2) comprometió
el rendimiento del cultivo.During 1999-2000 season kiwifruit
plants (Actinidia deliciosa (A. Chev.) C. F.
Liang et A. R. Ferguson var. deliciosa cv
Hayward) were thinned 19 days after full
bloom, according to 3 thinning levels (30,
40 and 50 fruits/m2). Three fruiting shoot
types were identified: strong, medium and
week. Growth evolution was registered. At
harvest, weight, solid soluble content,
firmness and pH were measured.
• The highest, medium and lowest levels:
30, 40 and 50 fruits/m2) produced 125, 121
and 113 g average weight respectively. All
fruits overcome the minimum exportation
weight.
• Week fruiting shoots produced the lightest
and softest fruits. No effects of fruiting shoots
were found for solid soluble content and pH.
• Fruit growth rate was favored by intense
thinning but thinning at 30 fruits/m2 affected
crop yield.Fil: Godoy, Carlos.Fil: Arpaia, Rodolfo.Fil: Tognetti, Jorge
Morphological Description of Selected Pigeonpea (\u3ci\u3eCajanus cajan\u3c/i\u3e (L.) Millsp.) Lines
Seventeen pigeonpea pure line accessions selected for desirable forage traits and three commercial cultivars were described according to morphological characters. The following descriptors were used: growth habit, plant height, number of primary and secondary branches, stem color and thickness, leaf shape and hairiness, flower base and second color, pattern of flower streaks, flowering pattern, immature and mature pod color, pod form and hairiness, seed color pattern, base and second seed color, seed eye (region around hilum) color and seed shape and width. Each individual line and cultivar was satisfactorily distinguished from the others by the chosen characters
Alternative splicing and transcription elongation in plants
Alternative splicing and transcription elongation by RNA polymerase II (RNAPII) are two processes which are tightly connected. Splicing is a co-transcriptional process, and different experimental approaches show that splicing is coupled to transcription in Drosophila, yeast and mammals. However, little is known about coupling of transcription and alternative splicing in plants. The kinetic coupling explains how changes in RNAPII elongation rate influence alternative splicing choices. Recent work in Arabidopsis shows that expression of a dominant negative transcription elongation factor, TFIIS, enhances exon inclusion. Furthermore, the Arabidopsis transcription elongation complex has been recently described, providing new information about elongation factors that interact with elongating RNAPII. Light regulates alternative splicing in plants through a chloroplast retrograde signaling. We have recently shown that light promotes RNAPII elongation in the affected genes, while in darkness elongation is lower. These changes in transcription are consistent with elongation causing the observed changes in alternative splicing. Altogether, these findings provide evidence that coupling between transcription and alternative splicing is an important layer of gene expression regulation in plants.Fil: Godoy Herz, Micaela Amalia. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Fisiología, Biología Molecular y Neurociencias. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Fisiología, Biología Molecular y Neurociencias; ArgentinaFil: Kornblihtt, Alberto Rodolfo. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Fisiología, Biología Molecular y Neurociencias. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Fisiología, Biología Molecular y Neurociencias; Argentin
Seasonal Variation of Tannin Content on Pigeon Pea (\u3cem\u3eCajanus Cajan\u3c/em\u3e (L.) Millsp) Plants
Tannins reduce forage digestibility and palatability by reacting with proteins (Makkar, 1989) and due to that, tannin content is considered to be an important characteristic of leguminous crops and it has been used as a selection criterion on pigeon-pea improvement programs (Godoy et al., 1994). In Southeastern Brazil, pigeon pea is less consumed by bovines in the rainy season (October through March) than in the dry season (from April on), when flowering occurs. Alencar et al. (1991) found very little consumption by Canchim cows during the rainy season, and Lourenço et al. (1984) recommend pigeon-pea for feeding bovines in the dry season
Leaf, Pod and Whole Plant Tannin Contents in Pigeon Pea (\u3cem\u3eCajanus cajan\u3c/em\u3e (L.) Millsp)
Tannin content is an important characteristic of leguminous crops and it has been used as a selection criterion in pigeon-pea improvement programmes (Godoy et al., 1994). In south-eastern Brazil, pigeon pea is often consumed by bovines in the dry season (from April though October), after flowering occurs, and is recommended in some cases, specifically for that time of the year (Lourenço et al., 1994). Since tannin content is being used as a selection criterion and the animals in the dry season preferentially eat pods and leaves, an experiment was conducted to compare whole plant, leaf and pod tannin content
Irrigação do amendoim por sulcos de infiltração
A trial was carried out in Piracicaba, State of São Paulo, Brazil, during 1974, to evaluate the effect of furrow irrigation on the peanut (Arachis hypogaea L.) crop grown during late dry season. Six irrigations of 25.5 mm were made as needed, totalizing 153 mm. During the period of this study 161.3 mm of rainfall were registered. Weekly data were taken per plant of irrigated and non-irrigated plots, including: root dry weight, shoot dry weight and pod dry weight. Final data were taken on number of plants per meter of row and yield. The following conclusion could be drawn from this experiment: late planting allowed longer vegetation period than the usual; irrigated plants had better development than the non-irrigated; irrigation improved yield per hectare but not per plant.Com a finalidade de avaliar o comportamento da cultura da seca de amendoim (Arachis hypogaea L.), quando submetida à irrigação, foi realizado em Piracicaba, São Paulo, um experimento, comparando a cultura normal da seca, com a cultura irrigada através de sulcos de infiltração, ambas semeadas em época mais tardia que a usual. A cultura irrigada recebeu um total de 153 mm de água de irrigação, dividido em seis aplicações de 25,5 mm, em adição a 161,3 mm de precipitações naturais. Semanalmente, foram efetuadas as seguintes determinações para as duas culturas: média, por planta, do peso das raízes, parte aérea e frutos secos. Ao final do experimento, foram determinados o número de plantas por metro e produção, por planta e por hectare. As principais conclusões foram: a semeadura tardia provocou aumento na duração do ciclo da cultura; as plantas da cultura irrigada tiveram maior desenvolvimento que as da cultura não irrigada; a irrigação possibilitou maior produção por hectare, mas não por planta
Fast Mid-IR Flashes Detected During Small Solar X-Ray Bursts
Solar observations in the mid-infrared 8-14 \mu\m band continuum were carried
out with cadence of 5 frames per second, in December 2007. Rapid small heated
sources, with typical duration of the order of seconds, were found on the
bright plage-like areas around sunspots, in association with relatively weak
GOES soft X-ray bursts. This work presents the analysis of fast mid-infrared
flashes detected during a GOES B2.0-class event on 10 December 2007, beginning
at about 10:40 UT. Rapid brightness temperature enhancements of 0.5 to 2.0 K
were detected at the Earth by a microbolometer array, using a telescope with
10.5 cm diameter aperture producing a diffraction limited field-of-view of 25
arcsec. Minimum detectable temperature change was of 0.1 K. The corresponding
fluxes are 30-130 solar flux units. At the solar surface the estimated rapid
brightenings were of 50-150 KComment: 12 pages including 6 figures. Accepted by Solar Physics, April 201
Evaluation of Pigeon Pea Lines for Biological Soil Decompaction
Soil decompaction is generally achieved through mechanical cultivation practices; however biological processes can significantly add to this process through root growth, development, and later senescence. This study was carried out in Piracicaba, SP, Brazil and had the purpose of selecting, among forty one pure pigeon pea lines, the most efficient genotypes that promote soil decompaction by roots penetrating compacted soil layers. Utilizing artificially compacted 30 mm high soil blocks, in a series of experiments, these lines were compared to the cultivar Fava Larga taken as a standard. Three lines were preliminarily selected out of the initial group, and afterwards, in more detailed screenings by monitoring soil resistance to penetration and also evaluating the behavior of Tanzania grass plants seeded after pigeon pea, two of them, g5-94 and g8-95, were selected as possessing the most fit root system to penetrate compacted soil layers
Testes de vigor em sementes de algodão (Gossypium Hirsutum L.) deslintadas quimicamente
With the purpose of determining the best vigor tests for cotton seeds, laboratory tests and a field experiment were made, using chemically delinted seeds of two cultivars, I AC 13-1 and IAC RM-3, stored in a dry chamber and under laboratory conditions. The following laboratory tests were performed: 1. percentage of emergence; 2. velocity of emergence - based on the number of plants emerged daily; 3 germination - being it's first counting as a vigor test; 4. rapid aging - the seeds were kept in the rapid aging chamber for 36, 48 60 and 72 hours; 5 ammonium chloride - the seeds were imerged in a 4% solution for 1,2 and 3 hours. Seed yield and the percentage and velocity of emergence were evaluated in the field experiment. The statistical analysis and interpretation of the results indicated that: the number of days required to make the last counting of the germination can be reduced; the first counting of this test was not efficient to determine the seed vigor; the best vigor test was obtained by keeping the seeds in the rapid aging chamber for 72 hours.Sementes deslintadas quimicamente de duas cultivares de algodão, IAC 13-1 e IAC RM 3, armazenadas em câmara sêca e ambiente de laboratório, sem controle de temperatura e umidade, foram submetidas a diversos testes de vigor e a um experimento de campo, com a finalidade de se procurar determinar os testes mais indicados para este tipo de sementes. Foram utilizados os seguintes testes, em cada época: porcentagem de emergência, calculando-se a porcentagem final de emergência em canteiros para cada tratamento; velocidade de emergência, anotando-se diariamente, no teste anteriormente descrito, o número de plântulas emersas e fazendo-se o cálculo do índice de velocidade de emergência; teste de germinação utilizando-se a sua primeira contagem como teste de vigor; quatro testes de envelhecimento rápido, variando entre eles os tempos de permanência das sementes na câmara de envelhecimento, que foram de 36, 48, 60 e 72 horas, após o que eram instalados testes de germinação; três testes de cloreto de amonio, à 4%, variando entre eles períodos de imersão das sementes na solução, que foram de 1, 2 e 3 horas, após o que as sementes eram lavadas e em seguida eram instalados testes de germinação. Os resultados destes testes foram submetidos a análise de correlação; estes mesmos resultados, mais os de porcentagem de emergência, velocidade de emergência e produção, obtidos no ensaio de campo, foram submetidos a análise de variância e teste de Tukey. As análises e interpretações dos resultados permitiram as seguintes conclusões principais: o número de dias para a última contagem do teste de germinação pode ser reduzido; a primeira contagem do teste de germinação não se revelou eficiente como teste de vigor; o teste de envelhecimento rápido, com o período de permanência das sementes na câmara de envelhecimento de 72 horas, foi o melhor teste de vigor
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