Correlación entre superficie foliar y producción en vid

En el presente trabajo se demuestra que existe correlación entre la producción de una plata de vid y la superficie foliar media de sus hojas Nº 6 provenientes de brotes fructíferos primarios, y que al aumentar el rendimiento, en peso, de frutos disminuye la graduación glucométrica en ellos. Asimismo se ha determinado que la producción en fruto está en función de la superficie foliar media de las hojas Nº 6, 7 y 8, conjuntamente, pero que el valor de la "r" en este caso no alcanza la elevada significancia que tiene cuando se estudia con respecto a la superficie media de las hojas Nº 6, solamente. Se acompañan 8 gráficos donde se puede apreciar la distribución de las observaciones y los respectivos valores de "r".

Correlación entre superficie foliar y rendimiento, como posible fundamento de una poda racional en vid

En el presente trabajo se confirman conclusiones anteriores respecto a la correlación existente entre la superficie total media de las hojas sextas de brotes fructíferos primarios y el rendimiento, en peso, de uvas. Las conclusiones se hacen extensivas a las hojas quintas, con ubicación similar a las anteriores. En esta correlación no influye la riqueza de poda, manteniéndose inalterable al variar aquélla en intensidad. Se realiza un estudio detenido de las relaciones entre intensidad de poda, producción de frutos, graduación glucométrica de éstos y superficie foliar, concluyendo que a medida que se incrementa el número de yemas dejadas sobre la planta en la poda, aumenta correlativamente el rendimiento de frutos y su concentración azucarina, pero esto último hasta un cierto límite, traducido gráficamente en el punto máximo de una curva, que sería el punto de equilibrio entre vigor de la planta, producción y calidad de ésta. Luego disminuye progresivamente la riqueza de azúcar de la uva mientras aumenta el rendimiento de frutos. La superficie foliar total de la hojas sextas consideradas sigue el ritmo de la producción de uva. Se sugiere considerar como base de la poda vitícola que tienda al logro de un producto de calidad, en el punto de equilibrio establecido, por lo que será importante determinar para cada variedad vitícola el número de yemas dejadas en la poda con la que se concretará el máximo de rendimiento y concentración de azúcar, lo que se considera puede transformarse en el fundamento de la futura tipificación vitivinícola regional

Algunas consideraciones acerca de la superficie foliar del viñedo

Las hojas representan el centro básico de la actividad de la vid, en ellas se realizan múltiples funciones que van desde las funciones fisiológicas más conocidas entre las que destaca la fotosíntesis, a través de la cual las hojas captan de la atmosfera la energía luminosa, que trasforman en energía química para trasformar el anhídrido carbónico (CO2) atmosférico en hidratos de carbono, en azúcares, que son el primer eslabón de todas las cadenas metabólicas de la planta, azúcares que la vid utilizará para edificar los diferentes tejidos y órganos, que empleará como fuente de energía para las diferentes funciones de crecimiento y metabolismo, azúcares que acumula como reserva en frutos o en los o en otras partes de las plantas (hojas, tallos o raíces); con el concurso de los azúcares las plantas obtienen los restantes compuestos orgánicos, desde las proteínas, las hormonas o los ácidos orgánicos tienen su origen en los azucares.

La superficie foliar del viñedo: Más reflexiones

La superficie foliar total del viñedo LAI (m2/m2) es un indicador de la potencialidad general, su medición en el viñedo es muy laboriosa, pues si se quiere con precisión hay que recurrir a medidores de superficie portátiles o recurrir a métodos destructivos que requieren tomar muestras muy grandes de hojas y medir en laboratorio, en otros casos hay cierto equipamiento más o menos sofisticado que da buenas aproximaciones.

Absorption and mobility of foliar-applied boron in soybean as affected by plant boron status and application as a polyol complex

In the present study (i) the impact of plant Boron (B) status on foliar B absorption and (ii) the effect of B complexation with polyols (sorbitol or mannitol) on B absorption and translocation was investigated. Soybean (Glycine max (L.) Meer.) plants grown in nutrient solution containing 0 μM, 10 μM, 30 μM or 100 μM 11B labelled boric acid (BA) were treated with 50 mM 10B labelled BA applied to the basal parts of two leaflets of one leaf, either pure or in combination with 500 mM sorbitol or mannitol. After one week, 10B concentrations in different plant parts were determined. In B deficient leaves (0 μM 11B), 10B absorption was significantly lower than in all other treatments (9.7% of the applied dose vs. 26%–32%). The application of BA in combination with polyols increased absorption by 18–25% as compared to pure BA. The absolute amount of applied 10B moving out of the application zone was lowest in plants with 0 μM 11B supply (1.1% of the applied dose) and highest in those grown in 100 μM 11B (2.8%). The presence of sorbitol significantly decreased the share of mobile 10B in relation to the amount absorbed. The results suggest that 11B deficiency reduces the permeability of the leaf surface for BA. The addition of polyols may increase 10B absorption, but did not improve 10B distribution within the plant, which was even hindered when applied a sorbitol complex.

Long-term foliar persistence and efficacy of spinosad against beet armyworm under greenhouse conditions.

BACKGROUND: The immediate lethality caused by spinosad has been widely studied on Spodoptera exigua (H ¿ ubner). However, long-term effects can also provide valuable information on insecticide toxic action. Here, the persistence of spinosad on Capsicum annuum L. foliage and the lethal and sublethal effects of greenhouse-aged foliar residues of this insecticide on third instars of S. exigua are reported. RESULTS: Foliage was collected at 0, 3, 5, 10, 20, 30, 40 and 50 days after application, and spinosad residues were measured. Residues decreased over time according to first-order kinetics. The average rate constant and half-life of disappearance were 4.44×10?3 and156 daysand5.80×10?3 and120 days for60and120 mg L?1 respectively. Larval mortalitygradually decreased, corresponding to the residues, but was still appreciable (35 and 65% for 60 and 120 mg L?1 respectively) when the larvae were fed with foliage collected 50 days after treatment. Subsequently, pupal development was reduced and varied between 20 and 60% and between 21 and 41% for 60 and 120 mg L?1, respectively, in all ages of leaf residues that were bioassayed. At all time points, the consumption rate by the larvae was reduced between 62 and 84% for both concentrations that were bioassayed. CONCLUSION: It is concluded that, under the present greenhouse conditions, the degradation of spinosad was slower than that reported by other authors in the field, and, because of that, its residues could cause lethal and sublethal effects to S. exigua larvae.

Ensayo de fertilización foliar sobre regenerado de pino rodeno en Cuéllar (Segovia)

El regenerado de Pinus pinaster Ait. en la tierra de pinares segoviana presenta frecuentemente, en estado de monte bravo, un desarrollo deficiente de la guía y de las ramas del tercio superior de la copa. El objetivo del presente estudio es tratar de determinar si este deficiente desarrollo está relacionado con alguna carencia nutricional. Para ello se realiza un ensayo de fertilización foliar y se analiza su influencia sobre la Longitud de las acículas y la Longitud de los ramillos desarrollados en el periodo vegetativo siguiente a la fertilización. Se consideran cuatro localizaciones diferentes y tres tratamientos distintos (Testigo, T, sin fertilización; fertilización simple, F; y fertilización doble, FF).

From plant surface to plant metabolism: the uncertain fate of foliar-applied nutrients

The application of agrochemical sprays to the aerial parts of crop plants is an important agricultural practice world-wide. While variable effectiveness is often seen in response to foliar treatments, there is abundant evidence showing the beneficial effect of foliar fertilizers in terms of improving the metabolism, quality, and yields of crops. This mini-review is focused on the major bottlenecks associated with the uptake and translocation of foliar-applied nutrient solutions. A better understanding of the complex scenario surrounding the ultimate delivery of foliar-applied nutrients to sink cells and organs is essential for improving the effectiveness and performance of foliar fertilizers.

Impact on agronomic parameters in Vines and wine quality of foliar treatments with specific fractions of yeast derivatives

In hot Spanish climate, Toledo, Syrah and Sauvignon blanc Vineyard were treated in pre veraison with yeast derivatives RD-LM and RD- LA to stimulate phenolic and aromatic maturity respectively (application of yeast derivatives specifically designed to be used with the patent foliar application technology WO/2014/024039, Lallemand Inc. Canada). For studied effects in berry and wine composition three harvest time had been done. Experimented yeast derivatives had no significant effects on yield components and vegetative growth in both varieties. The Syrah RD-LM variety presented higher total and extractable anthocyanins and also more amount of tannins, although this last ones are not evident in the sensory analysis. The sensory analysis of wine has given very similar results in both varieties but with significant results in favored by phenols and tannins derived RD- LM and RD-LA respectively.

A mitogen-activated protein kinase of the corn leaf pathogen Cochliobolus heterostrophus is involved in conidiation, appressorium formation, and pathogenicity: Diverse roles for mitogen-activated protein kinase homologs in foliar pathogens

Fungal pathogens perceive and respond to molecules from the plant, triggering pathogenic development. Transduction of these signals may use heterotrimeric G proteins, and it is thought that protein phosphorylation cascades are also important. We have isolated a mitogen-activated protein kinase homolog from the corn pathogen Cochliobolus heterostrophus to test its role as a component of the transduction pathways. The new gene, CHK1, has a deduced amino acid sequence 90% identical to Pmk1 of the rice blast fungus Magnaporthe grisea and 59% identical to Fus3 of Saccharomyces cerevisiae. A series of chk1 deletion mutants has poorly developed aerial hyphae, autolysis, and no conidia. No pseudothecia are formed when a cross between two Δchk1 mutants is attempted. The ability of Δchk1 mutants to infect corn plants is reduced severely. The growth pattern of hyphae on a glass surface is strikingly altered from that of the wild type, forming coils or loops, but no appressoria. This set of phenotypes overlaps only partially with that of pmk1 mutants, the homologous gene of the rice blast fungus. In particular, sexual and asexual sporulation both require Chk1 function in Cochliobolus heterostrophus, in contrast to Pmk1, but perhaps more similar to yeast, where Fus3 transmits the mating signal. Chk1 is required for efficient colonization of leaf tissue, which can be compared with filamentous invasive growth of yeast, modulated through another closely related mitogen-activated protein kinase, Kss1. Ubiquitous signaling elements thus are used in diverse ways in different plant pathogens, perhaps the result of coevolution of the transducers and their targets.

Sulfuric acid rain effects on crop yield and foliar injury /

Mode of access: Internet.

The increase in length of foliar traces in certain evergreen plants /

Thesis (M.S.)--Cornell University, 1916.

Important biological and morphological characteristics of the foliar-feeding aphids of pecan /

Issued May 1978.

Effects of boron foliar applications on vegetative and reproductive growth of sunflower

Foliar application may be used to supply boron (B) to a crop when B demands are higher than can be supplied via the soil. While B foliar sprays have been used to correct B deficiency in sunflower (Helianthus annuus L.) in the field, no studies have determined the amount of B taken up by sunflower plant parts via foliar application. A study was conducted in which sunflower plants were grown at constant B concentration in nutrient solution with adequate B (46 mum) or with limited B supply (0.24, 0.40 and 1.72 mum) using Amberlite IRA-743 resin to control B supply. At the late vegetative stage of growth (25 and 35 d after transplanting), two foliar sprays were applied of soluble sodium tetraborate (20.8 % B) each at 0, 28, 65, 120 and 1200 mm (each spray equivalent to 0, 0.03, 0.07, 0.13 and 1.3 kg B ha(-1) in 100 L water ha(-1)). The highest rate of B foliar fertilization resulted in leaf burn but had no other evident detrimental effect on plant growth. Under B-deficient conditions, B foliar application increased the vegetative and reproductive dry mass of plants. Foliar application of 28-1200 mm B increased the total dry mass of the most B-deficient plants by more than three-fold and that of plants grown initially with 1.72 mum B in solution by 37-49 %. In this latter treatment, the dry mass of the capitulum was similar to that achieved under control conditions, but in no instance was total plant dry mass similar to that of the control. All B foliar spray rates increased the B concentration in various parts of the plant tops, including those that developed after the sprays were applied, but the B concentration in the roots was not increased by B foliar application. The B concentration in the capitulum of the plants sprayed at the highest rate was between 37 and 93 % of that in the control plants. This study showed that B foliar application was of benefit to B-deficient sunflower plants, increasing the B status of plant tops, including that of the capitulum which developed after the B sprays were applied. (C) 2003 Annals of Botany Company.

Estimation and mapping of foliar chemical levels in a coastal eucalypt forest using CASI data

Proceedings of the 11th Australasian Remote Sensing and Photogrammetry Conference