Academic literature on the topic 'Vigne – Irrigation'

Deficit irrigation is one of the most researched irrigation water management techniques for vines with many potential benefits for successful grape production. For optimal growth and grape quantity of individual variety, suitable water quantity over growing season should be provided. Due to more frequent droughts vine irrigation will be needed also in Slovenia. The principle of deficit irrigation is affecting vine growth and quality and quantity of the yield by adding smaller amount of water than optimal. Decreased vine growth (reduced growth of shoots, 15.5 % for 'Monastrell, reduced leaf area, reduced pruning mass), smaller berries, and thus yield quantity from 38 % to 57 % for ‘Monastrell’ and 24 % to 27 % for 'Tempranillo', respectively, improved berry composition (higher sugar and antocianin content, lower acid content), better water use efficiency, meaning higher yield per unit of added water, are expected. Most suitable method for deficit irrigation management of vines is by measuring plant water potential. For successful transfer of deficit irrigation in practice, good knowledge of critical growth stages of irrigated vine variety and its behavior in a certain environment is needed. Successful application of this irrigation method in practice will be possible only with financial and expert support.

This paper describes an investigation on the effects of deficit irrigation treatments on phenolic compounds and physiological activities of Fantasy Seedless table grape variety. Research was conducted in Viticultural Research Institute of Manisa, located in Aegean Region of Turkey, during two consecutive years (2016–2017). Three irrigation treatments were assayed; namely full irrigation (T-F), deficit irrigations (T-35 and T-65). In T-F, soil water deficit in the 90 cm within the one week intervals was completed to the field capacity. T-35 and T-65 treatments received 35% and 65% of water applied to T-F. Sub-surface drip irrigation system was used in the research and soil water content was measured by MobiCheck probe while vine water status was monitored through midday leaf water potential before the irrigations. Results showed that water deficit treatments (T-35 and T-65) affected berry composition particularly individual phenolics [Gallic acid, (+)(−) Catechine, (−)-Epigallocatechin gallate, (−)-Epicatechin gallate, Caftaric acid, Chlorogenic acid, Caffeic acid, p-Coumeric acid, Ferulic acid, Sinapic acid, Trans-Resveratrol, Myricetin, Quercetin hydrate, Kaempferol, Oenin Chloride, Delphinidin Chloride, Cyanidin Chloride, Malvidin Chloride] differently. The highest Catechine content in the samples was obtained from T-65, T-35 and T-F treatments, respectively. Furthermore it was determined that DI treatments did not change the Myricetin and Quercetin hydrate contents in 2017. On the other hand minimum Ψmd value was observed from the T-35 treatment in both years. Last of all, our findings show a strong relationship between the amount of water and berry composition values especially individual phenolics which are benefical to health.

The effect of foliar salt uptake on potted grapevine growth and ionic composition was investigated in a split plot trial. The main plot was a 2 × 2 factorial consisting of separately irrigating the roots and foliage with nonsaline or saline (25 mm NaCl) solutions. The subplot was a 4 × 2 factorial consisting of four grape (Vitis vinifera) cultivars on their own roots or `Ramsey' (Vitis champini) rootstock. Saline foliar irrigation over 27 weeks reduced total vine growth by 14% while saline root irrigation had no effect. Leaf Na and Cl concentrations were elevated by saline foliar and saline root irrigation. The increases in concentrations with saline foliar irrigation were four times those with saline root irrigation. Leaf K concentration was reduced by saline foliar irrigation and increased by saline root irrigation. With saline irrigation of roots and foliage the Cl and Na levels were highest in the leaves of `Shiraz', but with saline irrigation of only the roots `Sultana' had the higher levels of leaf Cl and `Shiraz' the highest leaf Na. Saline foliar irrigation had no effect on the concentrations of Na, Cl, and K in the roots. In `Sultana', saline foliar irrigation did not affect the leaf concentrations of N, NO3-N, P, Mg, Zn, and Cu. It increased the leaf concentration of Fe, and decreased that of Mn. Rootstock modified the effect of salinity on Fe concentrations. The B concentration was decreased by saline irrigation of either the foliage or the roots, but not by saline irrigation of both. In roots, saline foliar irrigation increased B in own-rooted vines, but not in those on `Ramsey' rootstock.

<p style="text-align: justify;"><strong>Aims</strong>: A study was conducted to compare traditional vineyard irrigation (TI) using one drip emitter per vine, and partial root zone drying irrigation (PRD) using two drip emitters per vine (one per each vine side), at 2 rates of water application (controlled deficit (TI4 and PRD4) and non limiting (TI8 and PRD8)).</p><p style="text-align: justify;"><strong>Methods and results</strong>: Individual vine transpiration and vine water status were estimated from sap flow measurements by a stem heat balance method and midday stem water potential. The quality of the harvest was not significantly changed by the treatments. However, the vegetative growth was lower for the low irrigation rate treatments (TI4 and PRD4) and the PRD8 (compared to TI8). The total amount of water transpired by the vines during the season was estimated to 147 l/m2 without water limitation. A limiting water supply (TI4) lessened vine water use and improved the fraction of supplied water trapped by the vines (81 % for TI4 and 66 % for TI8). PRD decreased the transpiration of the vines, but also the efficiency of use of irrigation water.</p><p style="text-align: justify;"><strong>Significance and impact of study</strong>: Limited water supply saved water and improved the water capture efficiency by the roots of the vines. PRD irrigation saved water but the vine water capture efficiency was lower, limiting the practical interest of the method.</p>

A weighing lysimeter (with a soil container 2 m wide, 4 m long and 2 m deep) was installed at the University of California's Kearney Ag Center in 1987. Diurnal, daily and seasonal vine water use has been measured yearly since then. Vine water use was 350, 400 and 580 mm the first, second and third years after planting. respectively. Vine water use (from budbreak to October 31) the subsequent four years averaged 815 mm per year. Reference crop ET (ETo) averaged 1172 mm (from budbreak to October 31) over the course of the study. Diurnal vine water use was highly correlated with the diurnal course of solar radiation. Maximum ET averaged 50 L vine-1 day-1 during the middle part of the growing season. Experimental vines surrounding the lysimeter were irrigated at various fractions (from 0 to 140% in increments of 20%) of vine water was measured with the weighing lysimeter. Maximum yields were obtained with the 80% irrigation treatment This study demonstrated the deleterious effects of both over and under irrigation on yield of grapevines.

Plastic mulch ground cover and drip irrigation have produced substantial increases in yield and earliness of melons. However, such practices affect water movement, and nutrient and salt distribution in the soil. Salt levels in the soil after a melon crop using drip or flood irrigation increased in bare soil but decreased where plastic mulch had been used. Apparently capillary rise of water in response to surface evaporation brought salts up into the root zone. Very little of the applied N was detectable at the end of the study. However, enhanced early vine growth due to N application where drip irrigated but not where flood irrigated indicated that flood irrigation may have caused earlier N losses. Yield responses to N regardless of irrigation method indicated that early availability may have been most important. Yield increases were found for drip vs flood irrigation, and for plastic mulch vs bare soil, both of which may have been earliness effects; but the later treatments did not get the chance to catch up due to the occurrence of vine decline.

Precision irrigation of wine grape is hindered by the lack of an automated method for monitoring vine water status. The objectives of this study were to: Validate an automated model for remote calculation of a daily crop water stress index (CWSI) for the wine grape (Vitis vinifera L.) cultivar Malbec and evaluate its suitability for use in irrigation scheduling. Vines were supplied weekly with different percentages of evapotranspiration-based estimated water demand (ETc) over four growing seasons. In the fifth growing season, different daily CWSI threshold values were used to trigger an irrigation event that supplied 28 mm of water. All three indicators of vine water status (CWSI, midday leaf water potential (Ψlmd), and juice carbon isotope ratio (δ13C)) detected an increase in stress severity as the irrigation amount decreased. When the irrigation amount decreased from 100% to 50% ETc, 70% to 35% ETc, or the daily CWSI threshold value increased from 0.4 to 0.6, berry fresh weight and juice titratable acidity decreased, juice δ13C increased, the weekly CWSI increased, and Ψlmd decreased. Under the semi-arid conditions of this study, utilizing a daily CWSI threshold for irrigation scheduling reduced the irrigation amount without compromising the yield or changes in berry composition and remotely provided automated decision support for managing water stress severity in grapevine.

Several irrigation treatments were evaluated on ‘Sovereign Coronation’ (Vitis labruscana) table grapes at two vineyard sites in Ontario, Canada in 2003 to 2005 to assess the usefulness of the Food and Agriculture Organization of the United Nations Penman-Monteith equation for predicting vine irrigation needs. Data (relative humidity, wind speed, solar radiation, and temperature) for calculating reference evapotranspiration (ETo) were downloaded from the Ontario Weather Network. The five irrigation treatments were nonirrigated control plus four based on combinations of one of two ETo values [100% (ET100) or 150% (ET150)] and two crop coefficients [Kc (fixed at 0.75 or 0.5–0.8 based upon increasing canopy volume)] used to calculate the required irrigation water volume. Transpiration (Ts), leaf water potential (ψ), and soil moisture data were collected in all three seasons. Yield components data were collected and berries were analyzed for soluble solids, pH, titratable acidity (TA), anthocyanins, methyl anthranilate (MA), and total volatile esters (TVE). Irrigation typically increased Ts rate and soil moisture; the nonirrigated treatment showed consistently lower Ts and soil moisture over the three seasons. Irrigation also increased leaf ψ, which was lower throughout the three seasons for nonirrigated vines. Irrigation additionally increased yield and its various components (clusters per vine, cluster weight, and berries per cluster) in 2005. Berry weights were higher for irrigated treatments at both sites, and were consistently the main variable leading to yield increases. Soluble solids was highest for the Kc = 0.75 treatments. pH, TA, anthocyanins, and phenols were highest in nonirrigated treatments in 2003 and 2004, but were highest in irrigated treatments in 2005. MA and TVE were highest in the ET150 treatments. The use of irrigation was effective in reducing water stress and for improving yield and fruit composition of ‘Sovereign Coronation’ table grapes in the Niagara region of Ontario. The ET150 treatments were particularly beneficial. Soil and vine water status measurements indicated that irrigation was required for Summer 2003 and 2005 due to dry conditions.

Esca disease and Botryosphaeria dieback are currently considered as serious grapevine diseases which affect vineyard health and induce economic losses. Both of these trunk diseases (GTDs) are caused by a complex of pathogens, and foliar expression is influenced by several factors, including environmental factors such as water stress. To manage water stress in some vine areas, culture practice based on irrigation systems for limiting water stress have been developed; however, little knowledge of the influence of such systems on GTD emergence is currently available. The present paper addresses the impact of irrigation systems and climatic factors (rainfall and temperature) on the expression of GTDs, specifically esca and Botryosphaeria dieback. A field experiment on Chardonnay in North East Spain, a vine growing area where drought is present and which is managed by an irrigation system, was therefore carried out during a 3-year period. The water stress impact on GTD expression was evaluated by measuring the GTD incidence and analysing different physiological parameters at different phenological stages, including principal component analysis and gene expression. The main finding of this study was the significant roles of vine transpiration and water availability, which depend on irrigation volume and rainfall amount; together, they may explain the erratic symptom expression in plants infected by GTD fungi depending on the year. All these parameters are discussed to better understand the relationship between GTD expression, irrigation system and climatic factors.

Compte tenu des changements climatiques, la vigne dans les régions méditerranéennes est de plus en plus soumise à des conditions de sécheresse estivale prononcée provoquant des contraintes hydriques plus ou moins intenses. L’absorption d’azote, extrêmement dépendante de l’eau du sol, peut être très réduite, voire bloquée, entraînant une résonance importante sur la composition des baies, en particulier au niveau de la concentration en azote avec des conséquences sur la fermentescibilité des moûts. Ce travail comporte une étude très fine de la composition azotée des baies dans leurs différents compartiments tout au long du cycle végétatif. A la lumière des résultats, des solutions sont proposées, permettant d’assurer la qualité des raisins issus de vignes soumises à des conditions de contrainte hydrique sévère, parmi lesquelles la fertilisation foliaire azotée apparaît comme un moyen efficace. Notre travail met en évidence l’effet améliorateur, sur la composition azotée des baies de plants de Vitis vinifera, de pulvérisations foliaires d’azote à différents niveaux de contrainte hydrique : les effets « dose », « stade d’apport » et ceux de l’interaction croisée « dose-stade d’apport » sont explorés. L’effet de l’interaction « alimentation hydriquehauteur de haie foliaire » est également étudié. D’une manière générale, la fertilisation foliaire affirme son efficacité dans toutes les expérimentations et révèle que plus la carence azotée ou hydrique est marquée, plus l’effet de la fertilisation foliaire est important. L’apport à véraison, par rapport aux autres stades de développement, est le plus approprié pour améliorer la teneur des baies en azote. Dès la dose de 10 kg N/ha apportée à cette période clé, les carences azotées des moûts sont enrayées. Ce travail contribue à la connaissance de la distribution de l’azote apporté par voie foliaire, de l’évolution de certains acides aminés comme la glutamine et l’arginine ainsi que du métabolisme et de la remobilisation de l’azote dans la vigne durant la maturation. Nous révélons aussi l’incidence de la fertilisation foliaire azotée, de l’irrigation et de la hauteur de haie foliaire sur la synthèse des précurseurs d’arômes en particulier ceux du sulfure de diméthyle.

Les relations entre les états de développement végétatif ou reproductif de la vigne et la sensibilité aux attaques de l’oïdium et du botrytis sont complexes et pauvrement documentées dans la littérature. L’état de croissance de la plante peut agir de façon directe ou indirecte sur les maladies et ce travail a cherché à étudier et à décrire ces relations. Pour cela, un dispositif expérimental a été installé sur une parcelle près de Montpellier avec différentes modalités de gestion du sol (enherbement permanent ou semi-permanent, désherbage total, irrigation) qui ont permit de créer des conditions de croissance contrastées. L’hypothèse selon laquelle le développement épidémique de l’oïdium et du botrytis est positivement corrélé aux états de croissance de la vigne a été vérifiée. Pour le botrytis, les deux facteurs principaux qui expliquent cette relation positive sont les conditions climatiques et micro climatiques en interaction avec les états de croissance de la vigne. Pour l’oïdium, le facteur explicatif majeur a été la population d’organes sensibles à partir de la floraison. Un schéma théorique général qui prend en compte cette relation croissance-maladie, ainsi que les mécanismes explicatifs est proposé. Les conditions qui défavorisent la croissance et le rendement de la vigne défavorisent aussi le développement des maladies. Paradoxalement ces conditions ne permettent pas forcement de satisfaire les objectifs de rendement et de qualité. En effet, l’état de croissance qui produit le rendement le plus élevé est celui de la modalité irriguée et fertilisée (optimum de production). Le niveau de croissance qui prévient le plus les dégâts sur grappes est celui de la modalité avec un enherbement permanent (optimum sanitaire). Entre ces deux extrêmes, on trouve la modalité avec un enherbement semi-permanent, qui produit des rendements et des dégâts de maladies intermédiaires ainsi que le raisin qui a été jugé le meilleur pour la production de vin

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The objective of this study was to evaluate the responses of cowpea (Vigna Unguicullata L. Walp) produced under the effect of different irrigation with saline water and liquid biofertilizer doses. Held this experiment in an experimental area Federal Institute of CearÃ, located in the municipality of Umirim - CE with the cultivar of cowpea âBRS Pujanteâ. The experiment obeyed in a randomized block, in a split plot, totaling sixteen treatments and four repetitions. The plot consisted application of four different irrigation water with saline water (75; 100; 125 and 150% of crop evapotranspiration - ETc) and the subplots consisted of four different biofertilizer doses (0; 60; 120 e 180ml/plant). To perform irrigation was using a system drip. The water utility is classified as C4S1 and has electrical conductivity 3.81 dS.m-1. The biofertilizer was prepared in aerobic system, using water and cattle manure in the proportions of 1:1. The doses used were divided in three applications, this being performed at 10, 40 and 70 days after sowing â DAS. To 15, 45 and 75 DAS, they were analyzed chlorophyll content A e B and gas exchange in plants of cowpea, and the end of the experiment the growth, productive components and grain yield per plant. The results were subjected to the analysis of variance by F and their means compared by test Tukey and regression analysis. The results showed significant interaction between factors, getting meaningful answers to 75 DAS for the chlorophyll A. For gas exchange dose 120ml / bio-fertilizer plant was the best interacted with the laminae to 15 and 45 DAS. To 75 DAS the water depth was significant, adjusting the linear model for photosynthesis and stomatal conductance and quadratic for the concentration internal CO2 and transpiration. For growth , the increase in water depth provided to increase dry matter and total leaf Ãrea, being observed respectively adding up 32,42 and 64%. The increase of biofertilizer dose provided increment the number of sheets , fitting the quadratic model and reaching peak on the dose of 80 ml/plant. The production of dry grains , the interaction between the factors was significant , with higher averages in the blades of 100% of ETc and reaching a production of 23.76 and 23.07 g under the doses of 0 and 60 ml/plant of biofertilizers, respectively. Thus the application of different irrigation responded significantly culture , observed higher values when applied blades above 100 % of the ETc. For biofertilizers its application did not respond significantly the variables analyzed.
O objetivo deste trabalho foi avaliar as respostas do feijÃo-caupi (Vigna Unguicullata L. Walp) produzido sob efeito de diferentes lÃminas de irrigaÃÃo com Ãgua salina e doses de biofertilizante lÃquido. Para isso realizou-se este experimento em uma Ãrea experimental do Instituto Federal do CearÃ, localizado no municÃpio de Umirim - CE com a cultivar de feijÃo-caupi âBRS Pujanteâ. O experimento obedeceu ao delineamento em blocos ao acaso, em parcelas subdivididas, totalizando dezesseis tratamentos e quatro repetiÃÃes. As parcelas consistiram na aplicaÃÃo de 4 diferentes lÃminas de irrigaÃÃo com Ãgua salina (75; 100; 125 e 150% da evapotranspiraÃÃo da cultura - ETc) e as subparcelas diferentes doses de biofertilizante bovino (0; 60; 120 e 180 ml/planta). Para realizaÃÃo da irrigaÃÃo foi utilizado um sistema por gotejamento. A Ãgua utilizada foi classificada como C4S1 e possui condutividade elÃtrica de 3,81 dS.m-1. O biofertilizante foi preparado em sistema aerÃbico, utilizando Ãgua e esterco bovino fresco nas proporÃÃes de 1:1. As doses utilizadas foram parceladas em trÃs aplicaÃÃes, sendo estas realizadas aos 10, 40 e 70 dias apÃs a semeadura â DAS. Aos 15, 45 e 75 DAS, foram analisados o Ãndice de clorofila A e B e trocas gasosas em plantas de feijÃo-caupi, e ao final do experimento o crescimento, os componentes produtivos e produÃÃo de grÃos por planta. Os resultados obtidos foram submetidos a anÃlise de variÃncia pelo teste F e feito o teste de Tukey e anÃlise de regressÃo. Os resultados demonstraram interaÃÃo significativa entre os fatores, obtendo respostas significativas aos 75 DAS para o Ãndice de clorofila A. Para as trocas gasosas, a dose 120 ml/planta de biofertilizante foi a que melhor interagiu com as lÃminas de irrigaÃÃo aos 15 e 45 DAS. Aos 75 DAS a lÃmina de irrigaÃÃo foi significativa, ajustando-se ao modelo linear para a fotossÃntese e condutÃncia estomÃtica e quadrÃtica para a concentraÃÃo de interna de CO2 e transpiraÃÃo. Para o crescimento, o aumento da lÃmina de irrigaÃÃo proporcionou aumento para a matÃria seca total e Ãrea foliar, sendo observado respectivamente, acrÃscimo de atà 32,42 e 64%. O aumento da dose de biofertilizante proporcionou incremento ao nÃmero de folhas, ajustando-se ao modelo quadrÃtico e atingindo ponto mÃximo sobre a dose de 80 ml/planta. Quanto a produÃÃo de grÃos secos, a interaÃÃo entre os fatores se mostrou significativa, apresentando maiores mÃdias sob a lÃminas de 100% da ETc e atingindo uma produÃÃo de 23,76 e 23,07 g sob as doses de 0 e 60 ml/planta de biofertilizante, respectivamente. Desta forma à aplicaÃÃo de diferentes lÃminas de irrigaÃÃo respondeu de forma significativa a cultura, sendo observados maiores valores quando aplicado lÃminas acima de 100% da ETc. Para o biofertilizante sua aplicaÃÃo nÃo respondeu de forma significativa as variÃveis analisadas.

Conselho Nacional de Desenvolvimento CientÃfico e TecnolÃgico
As culturas agrÃcolas demandam grandes volumes de Ãgua no processo produtivo, sendo oportuno identificar quais os estÃdios de desenvolvimento com maior sensibilidade hÃdrica visando definir uma estratÃgia de manejo da irrigaÃÃo. Assim, objetivou-se, com esta pesquisa, avaliar os efeitos do dÃficit hÃdrico em diferentes estÃdios fenolÃgicos das cultivares de feijÃo-caupi, Sempre Verde e SetentÃo, com o intuito de obter informaÃÃes sobre a viabilidade tÃcnica do uso da irrigaÃÃo deficitÃria na cultura. O experimento foi conduzido na Ãrea experimental da EstaÃÃo AgrometeorolÃgica do Departamento de Engenharia AgrÃcola. O delineamento experimental foi de blocos ao acaso, com oito tratamentos e quatro repetiÃÃes, definidos em funÃÃo da Ãpoca de induÃÃo do dÃficit hÃdrico (em um, dois ou trÃs estÃdios fenolÃgicos), correspondente à aplicaÃÃo da metade da lÃmina de irrigaÃÃo do tratamento sem dÃficit hÃdrico. Foram avaliadas ao tÃrmino de cada estÃdio fenolÃgico as variÃveis: taxas de fotossÃntese, transpiraÃÃo e condutÃncia estomÃtica. Ao tÃrmino do ciclo foram analisadas a matÃria seca da parte aÃrea e a participaÃÃo de cada uma delas em relaÃÃo à produÃÃo de fitomassa seca total e o Ãndice de colheita. Avaliaram-se os componentes de produÃÃo (massa de cem grÃos, nÃmero de vagens por planta, comprimento das vagens, nÃmero de grÃos por vagem e produtividade). Estimaram-se ainda, os Ãndices de eficiÃncia de uso da Ãgua para a produÃÃo de matÃria seca total da parte aÃrea e para a produtividade de grÃos. As variÃveis foram submetidas à anÃlise estatÃstica realizando-se anÃlise de variÃncia (Teste F) e Teste de Tukey para comparaÃÃo de mÃdias. Os resultados mostraram que a cultivar SetentÃo foi superior estatisticamente em todas as variÃveis de trocas gasosas. A fotossÃntese e a transpiraÃÃo foram influenciadas pela interaÃÃo entre os tratamentos x cultivares x Ãpocas, com exceÃÃo da condutÃncia estomÃtica. A Ãpoca de floraÃÃo apresentou os maiores valores de transpiraÃÃo, e a condutÃncia estomÃtica atingiu os maiores valores na Ãpoca vegetativa. Os dÃficits de irrigaÃÃo e as cultivares interagiram e afetaram a produÃÃo e partiÃÃo da matÃria seca da parte aÃrea, Ãndice de colheita, componentes de produÃÃo e produtividade, porÃm nÃo influenciou o nÃmero de vagens por planta. O dÃficit hÃdrico, no estÃdio de formaÃÃo da produÃÃo (T2), nÃo influenciou a produÃÃo de matÃria seca total da parte aÃrea. O manejo da irrigaÃÃo com dÃficit na cultura do feijÃo-caupi pode resultar em maior eficiÃncia de uso da Ãgua por parte da cultura.
Agricultural crops require large volumes of water in the production process and it is important to identify the appropriate stages of development with higher water sensitivity in order to define a strategy for irrigation management. Thus, the aim of this research was to evaluate the effects of water stress at different growth stages of two cowpea cultivars, Sempre Verde and SetentÃo, in order to obtain information on the technical feasibility of using deficit irrigation for this crop. The experiment was conducted at the experimental site of the Agrometeorological Station of the Department of Agricultural Engineering. The experimental design was a randomized block with eight treatments and four replicates, according to the time of drought induction (in one, two or three phenological stages), and corresponding to the application of half the sheet of water of the treatment without water deficit. Rates of photosynthesis, transpiration and stomatal conductance were assessed at the end of each phenological stage. At the end of the growth cycle, shoot dry matter and its participation in total dry matter and harvest index were analyzed. The components of production (weight of one hundred grains, number of pods per plant, pod length, number of grains per pod and productivity) were evaluated. In addition, the water use efficiency for total shoot dry matter production and for grain yield was estimated. The variables were analyzed statistically by performing analysis of variance (F test) and Tukey's test for comparison of means. The results showed that the cultivar SetentÃo was statistically higher in all gas exchange variables. Photosynthesis and transpiration were influenced by the interaction between cultivars x treatments x times, but not stomatal conductance. Transpiration was highest during flowering while stomatal conductance was highest during vegetative growth. There was interaction between irrigation deficits and cultivars, which affected shoot dry matter production and partitioning, harvest index, yield components and yield, but not the number of pods per plant. Water shortages in the stage of yield formation (T2) did not influence total shoot dry matter. Irrigation management with deficits in cowpea can result in greater efficiency of water use by the crop.

Changes in the microclimate in a intercropping can also change the responses of plants to some abiotic factors, including, salinity. The aim of this study was to evaluate the influence of salinity of irrigation water on gas exchange, ion levels, growth, productivity and efficiency of land use in single and intercropped systems, using plant corn and beans-in-corda. The experiment was conducted for two years following a design in randomized blocks in split plots, and the plots formed by the year of cultivation (2012 and 2013), the subplots by salinity of irrigation water (0.9, 2.5 and 5.0 dS m-1), and the split of crop systems (bean-to-rope, corn and more bean-to-string corn in consortium). The irrigated crops were conducted during the dry seasons of the years 2012 and 2013, and samples were taken soil samples before and after each crop, and after the passage of the rainy seasons of 2013/2014. To facilitate the description of the results, the thesis was divided into two chapters. The first is related to growth and productivity. The variables analyzed were: biomass production, productivity and efficiency of land use. The second is related to gas and mineral nutrition exchanges. The variables analyzed were: stomatal conductance, photosynthesis, transpiration, water use efficiency, levels of Na+, K+ and Cl+ in the leaves and stem. The accumulation of salts in the soil increased in proportion to the electrical conductivity values of irrigation water, with the highest observed in maize, a fact explained by the longer cycle and increased the employed irrigation depth in this culture. Rainfall totals recorded in the rainy seasons of 2013 and 2014 were sufficient to promote the leaching of excess salts below the root zone of crops. The accumulation of salts in the soil did not influence gas exchange and efficiency of water use, but caused an increase in the levels of Na+ in the leaves and stems. Despite the differences observed in the levels of Na, one can not relate them the variables of gas exchange, since they were not affected by the irrigation water salinity. The effects of salts on the production of total biomass and productivity of the plants were more expressive in plants under monoculture, especially in the bean-to-rope culture. The microclimate condition of intercropping system may have contributed to reduce the influence of salinity on productivity, mainly of bean-to-rope culture, resulting in higher values of efficient land use.
As alteraÃÃes no microclima em um cultivo consorciado podem tambÃm alterar as respostas das plantas a alguns fatores abiÃticos, dentre eles, a salinidade. O objetivo do presente trabalho foi avaliar a influÃncia da salinidade da Ãgua de irrigaÃÃo sobre as trocas gasosas, teores de Ãons, crescimento, produtividade e eficiÃncia do uso da terra em sistemas de monocultivo e consÃrcio, utilizando-se plantas de milho e feijÃo-de-corda. O experimento foi realizado durante dois anos seguindo um delineamento em blocos ao acaso, em parcelas subsubdivididas, sendo as parcelas formadas pelo ano de cultivo (2012 e 2013), as subparcelas pela salinidade da Ãgua de irrigaÃÃo (0,9, 2,5 e 5,0 dS m-1) e as subsubparcelas pelos sistemas de cultivo (feijÃo-de-corda, milho e milho mais feijÃo-de-corda em consÃrcio). Os cultivos irrigados foram conduzidos durante as estaÃÃes secas dos anos 2012 e 2013, e foram realizadas coletas de amostras de solo antes e apÃs cada cultivo, e apÃs a passagem das estaÃÃes chuvosas de 2013/2014. Para facilitar a descriÃÃo dos resultados, a tese foi dividida em dois capÃtulos. O primeiro à referente ao crescimento e produtividade. As variÃveis analisadas foram: produÃÃo de biomassa, produtividade e eficiÃncia do uso da terra. O segundo à referente Ãs trocas gasosas e nutriÃÃo mineral. As variÃveis analisadas foram: condutÃncia estomÃtica, fotossÃntese, transpiraÃÃo, eficiÃncia do uso da Ãgua, teores de Na+, K+ e Cl+ nas folhas e caule. O acÃmulo de sais no solo aumentou proporcionalmente aos valores de condutividade elÃtrica da Ãgua de irrigaÃÃo, sendo os maiores observados na cultura do milho, fato explicado pela maior duraÃÃo do ciclo e maior lÃmina de irrigaÃÃo empregada nesta cultura. Os totais de chuvas verificados nas estaÃÃes chuvosas de 2013 e 2014 foram suficientes para promover a lixiviaÃÃo do excesso de sais abaixo da zona radicular das culturas. O acÃmulo de sais no solo nÃo influenciou as trocas gasosas e a eficiÃncia do uso da Ãgua, mas provocou aumento nos teores de Na+ nas folhas e caules. Apesar das diferenÃas observadas nos teores de Na, nÃo se pode relacionÃ-las as variÃveis de trocas gasosas, visto que estas nÃo sofreram influÃncia da salinidade da Ãgua de irrigaÃÃo. Os efeitos dos sais sobre a produÃÃo de biomassa total e produtividade das plantas se mostraram mais expressivos nas plantas sob monocultivo, notadamente na cultura do feijÃo-de-corda. A condiÃÃo microclimÃtica do sistema de consÃrcio pode ter contribuÃdo para reduzir a influÃncia da salinidade na produtividade, principalmente da cultura do feijÃo-de-corda, resultando em maiores valores do uso eficiente da terra.

CoordenaÃÃo de AperfeÃoamento de Pessoal de NÃvel Superior
Salinity has constituted today one of the main problems facing irrigated agriculture. Failure to proper management of the practice of irrigation by farmers, associated the prevailing climatic conditions in arid and semi-arid regions has contributed to the accelerated process of salinization, thus leaving several inactive irrigated areas for agriculture. In this context, the work herein developed was to examine the propensity of different strategies for handling irrigation through the use of lower quality water in salinization and sodification soil, besides evaluating the morphological, physiological, biochemical and productive responses, cultivars cowpea beans, to obtain information about the better understanding of the processes involved in the responses of salt tolerance, and enable the election cultivars adapted irrigation with saline water conditions. The experiment was conducted in pots in the open, in the experimental area of the weather station of the Federal University of CearÃ, Fortaleza, CearÃ, under an experimental design of randomized blocks in split plots. The two water regimes (plots) were based on the potential crop evapotranspiration (100 and 50% of ETpc). Already irrigation water salinity levels (0.95; 2.45; 3.95; 5.45 and 6.95 dS m-1) were distributed in the subplots, while the cultivars (Epace 10 and BRS Itaim) in subsubplots. The increased concentration of salts in irrigation water reduced the plant height, number of leaves, dry weight of shoot and the pH of the soil solution, except for the electrical conductivity of the soil that kept adding to the imposition of different salt concentrations. Due to the absence of leaching, the treatments irrigated with a blade 50% of ETpc maintained higher values of soil electrical conductivity and potassium levels in the soil, providing reduction in leaf area. Through the morphological variables, the cultivar Epace 10 showed better performance than BRS Itaim. The physiological responses analyzed, it was found that the levels of chlorophyll pigments a, b, and total carotenoid contents of the well are reduced by increasing the salt concentration in the irrigation water. Under conditions of lower water availability (50% of ETpc), to cultivate Epace 10 was higher for the content of photosynthetic pigments. There was no significant change in parameters associated with the emission of fluorescence due to salt and water stress. In general, we observed reductions in the behavior of gas exchange under the rise in salinity levels, thereby enhancing the interdependence between the variables analyzed. On the productive potential and biochemical responses analyzed it was found that the concentration of salts in irrigation water provided greater accumulation of N-aminossolÃveis content, proline and Cl- in the bean cowpea leaves. Under a water system 50% of ETpc, the N-aminossolÃveis content and K+ are higher than the system 100% of ETpc. The cultivar Epace 10 has higher accumulations N-aminossolÃveis and Cl-, besides presenting more free proline accumulation, under a water system 50% of ETpc. The total yield potential of the cowpea is reduced by the addition of salts in the irrigation water. The cultivar Epace 10 showed greater tolerance imposed management conditions, making it more suitable growing conditions in regions subject to water stress and / or saline.
A salinidade tem se constituÃdo hoje num dos principais problemas enfrentados pela agricultura irrigada. A falta de manejo adequado da prÃtica de irrigaÃÃo pelos produtores, associado as condiÃÃes climÃticas reinantes em regiÃes Ãridas e semiÃridas tem contribuÃdo para o acelerado processo de salinizaÃÃo dos solos, deixando assim diversas Ãreas irrigadas inativas para a prÃtica agrÃcola. Neste contexto, o trabalho desenvolvido buscou analisar a propensÃo de diferentes estratÃgias de manejo da irrigaÃÃo, atravÃs da utilizaÃÃo de Ãguas de qualidades inferiores, em salinizar ou sodificar o solo, alÃm de avaliar as respostas morfolÃgicas, fisiolÃgicas, bioquÃmicas e produtivas, de cultivares de feijÃo caupi, visando obter informaÃÃes acerca do melhor entendimento dos processos envolvidos nas respostas de tolerÃncia à salinidade, alÃm de possibilitar a eleiÃÃo de cultivares adaptadas as condiÃÃes de irrigaÃÃo com Ãguas salinas. O experimento foi conduzido em vasos, a cÃu aberto, na Ãrea experimental da EstaÃÃo AgrometeorolÃgica da Universidade Federal do CearÃ, Fortaleza, CearÃ, sob um delineamento estatÃstico de blocos ao acaso em parcelas subsubdivididas. Os dois regimes hÃdricos (parcelas) foram baseados pela evapotranspiraÃÃo potencial da cultura (100 e 50% da ETpc). Jà os nÃveis de salinidade da Ãgua de irrigaÃÃo (0,95; 2,45; 3,95; 5,45 e 6,95 dS m-1) foram distribuÃdos nas subparcelas, enquanto as cultivares (Epace 10 e BRS Itaim) nas subsubparcelas. O aumento da concentraÃÃo de sais na Ãgua de irrigaÃÃo reduziu a altura das plantas, o nÃmero de folhas, a massa seca da parte aÃrea e o pH da soluÃÃo do solo, no entanto, proporcionou um aumento linear na condutividade elÃtrica do solo. Devido a ausÃncia de lixiviaÃÃo, os tratamentos irrigados com uma lÃmina de 50% da ETpc mantiveram valores superiores da condutividade elÃtrica e dos teores de potÃssio no solo, propiciando reduÃÃo na Ãrea foliar. AtravÃs das variÃveis morfolÃgicas estudadas, a cultivar Epace 10 demonstrou melhor desempenho que a cultivar BRS Itaim. Quanto as respostas fisiolÃgicas analisadas, constatou-se que, os teores dos pigmentos da clorofila a, b e total, alÃm dos teores de carotenoides sÃo reduzidos com o aumento da concentraÃÃo de sais na Ãgua de irrigaÃÃo. Sob condiÃÃes de menor disponibilidade hÃdrica (50% da ETpc), a cultivar Epace 10 apresentou valores superiores nos teores de pigmentos fotossintÃticos. NÃo se verificou alteraÃÃo significativa nos parÃmetros associados à emissÃo da fluorescÃncia, devida ao estresse salino e hÃdrico. De maneira geral, foi possÃvel observar reduÃÃes nas respostas das trocas gasosas sob o aumento dos nÃveis de salinidade, reforÃando assim, a interdependÃncia entre as variÃveis analisadas. Sobre o potencial produtivo e respostas bioquÃmicas analisadas verificou-se que o aumento da concentraÃÃo de sais na Ãgua de irrigaÃÃo propiciou maior acÃmulo dos teores de N-aminossolÃveis, prolina e Cl- nas folhas do feijoeiro caupi. Sob um regime hÃdrico de 50% da ETpc, os teores de N-aminossolÃveis e K+ sÃo superiores aos do regime de 100% da ETpc. A cultivar Epace 10 apresenta maiores acÃmulos N-aminossolÃveis e de Cl-, alÃm de apresentar maior acÃmulo de prolina livre, sob um regime hÃdrico de 50% da ETpc. O potencial produtivo total do feijÃo caupi à reduzido pelo acrÃscimo de sais na Ãgua de irrigaÃÃo. A cultivar Epace 10 apresentou maior tolerÃncia as condiÃÃes de manejo impostas, tornando-se mais adaptada as condiÃÃes de cultivo em regiÃes sujeitas a estresse hÃdrico e/ou salino.

Conselho Nacional de Desenvolvimento CientÃfico e TecnolÃgico
O feijÃo-caupi à uma cultura tradicionalmente produzida nas regiÃes Norte e Nordeste. No estado do PiauÃ, seu baixo rendimento mÃdio ainda persiste nos dias atuais, apesar da cultura ser bem adaptada Ãs condiÃÃes edafoclimÃticas da regiÃo e de existirem cultivares melhoradas disponÃveis no mercado. Assim, estudos que descrevam melhores prÃticas de manejo da cultura com a combinaÃÃo adequada da densidade de plantas e lÃmina de irrigaÃÃo, sÃo importantes à medida que sÃo capazes de apresentar alternativas que possibilitem o aumento da eficiÃncia de utilizaÃÃo da Ãgua pela cultura e a reduÃÃo dos custos com insumos agrÃcolas. O objetivo desse trabalho foi avaliar a possÃvel interaÃÃo de nÃveis de Ãgua e densidade de plantas do feijÃo-caupi sobre os parÃmetros de crescimento, trocas gasosas, componentes de produÃÃo, produtividade de grÃos, eficiÃncia do uso da Ãgua e distribuiÃÃo da umidade no solo. O experimento foi conduzido no perÃodo de julho a setembro de 2012, no campo experimental da Embrapa Meio-Norte, localizado no municÃpio de Teresina, PiauÃ. Os tratamentos consistiram de cinco lÃminas de irrigaÃÃo (L5-150%, L4-120%, L3-90%, L2-60% e L1-30% da ETo) e quatro densidades populacionais (D1-150.00; D2-200.000; D3-250.000; D4-300.000 plantas ha-1). Houve interaÃÃo significativa, entre os nÃveis de irrigaÃÃo e as densidades populacionais nos componentes de produÃÃo, nÃmero de vagens por planta, peso de vagens, produtividade de vagens, comprimento de vagem, peso de cem grÃos, produtividade de grÃos e eficiÃncia do uso da Ãgua. A produtividade de grÃos apresentou valor mÃximo de 1.668,86 kg ha-1 com uma lÃmina de irrigaÃÃo de 390,88 mm associada à densidade de 241.000 plantas ha-1. Obteve-se o valor mÃximo de eficiÃncia do uso da Ãgua, 4,78 kg ha-1 mm-1, com a lÃmina de 342,97 mm e densidade populacional de 233.000 plantas ha-1. No que se refere à distribuiÃÃo da umidade do solo, sob as maiores lÃminas de irrigaÃÃo e nas diferentes densidades de semeadura, houve consumo hÃdrico diferenciado do feijÃo-caupi em funÃÃo da densidade de raÃzes. O padrÃo de extraÃÃo de Ãgua do solo pelas raÃzes do feijÃo-caupi foi diretamente proporcional Ãs densidades de semeadura avaliadas. NÃo houve grande variaÃÃo da extraÃÃo de Ãgua nas diferentes densidades do feijÃo-caupi quando submetido Ãs menores lÃminas de irrigaÃÃo. Sob uma lÃmina de irrigaÃÃo de L5 â 150% ETo e densidade de plantas de 241.000 plantas ha-1, o feijÃo-caupi responde melhor em termos produtivos, com a manutenÃÃo da capacidade de Ãgua disponÃvel no solo, na faixa aproximada de 80% (na camada de 0,10 m) a 60% (na camada de 0,30 m). A interaÃÃo significativa entre os nÃveis de irrigaÃÃo e as densidades populacionais para Ãrea foliar do feijÃo-caupi, indica que hà reduÃÃo nesse parÃmetro de crescimento com diminuiÃÃes nos nÃveis de Ãgua e densidade de plantas. Os maiores valores ocorrem com lÃmina de irrigaÃÃo de 367,86 mm e densidade de 188.000 plantas ha-1. Isoladamente, a aplicaÃÃo contÃnua de Ãgua elevou a taxa fotossintÃtica, a condutÃncia estomÃtica e a transpiraÃÃo com reduzidos valores nas menores lÃminas de irrigaÃÃo 201,73 mm e 260,39 mm.
The cowpea is a crop traditionally produced in the North and Northeast regions. In the state of PiauÃ, its low average income still persists today, despite the culture was well adapted to soil and climatic conditions of the region and there are improved cultivars available on the market. Thus, studies that describe best practices in crop management with the proper combination of plant density and irrigation levels, are important as they are able to present alternatives that enable increased efficiency of water use by the crop and reduce costs with agricultural inputs. The aim of this study was to evaluate the possible interaction of water levels and plant density on cowpea growth parameters, gas exchange, yield components, grain yield, efficiency of water use and distribution of soil moisture. The experiment was conducted during the period July to September 2012 in the experimental field of Embrapa Meio-Norte, located in the city of Teresina, PiauÃ. Treatments consisted of five irrigation (L5 -150%, L4 -120%, L3 - 90%, L2 - 60% and L1 - 30 % of ETo) and four densities (D1 â 150,000, D2 - 200,000, D3 -250,000, D4 â 300,000 plants ha-1). There was a significant interaction between irrigation levels and population densities for yield components, number of pods per plant, weight of pods, pod yield, pod length, pod weight of hundred grains, grain yield and water use efficiency. Grain yield showed the maximum value of 1668.86 kg ha- 1 with a water depth of 390.88 mm associated with the density of 241,000 plants ha- 1. Obtained the maximum efficiency of use of water, 4.78 kg ha-1 mm-1 with the blade of 342.97 mm and density of 233,000 plants ha-1. As regards the distribution of soil moisture under the higher irrigation regimes and different seeding rates, water consumption was different cowpea depending on the density of roots. The pattern of water extraction from the soil by roots of cowpea was directly proportional to the seeding densities evaluated. There was wide variation in water extraction in different densities of cowpea when subjected to minor irrigation. Under a water depth of L5 - 150% ETo and plant density of 241,000 plants ha- 1, the cowpea responsive in terms of production, maintaining the available water capacity in the soil, in the approximate range of 80% (in the layer of 0.10 m) to 60% (in the layer of 0.30 m). A significant interaction between irrigation levels and population densities for leaf area of cowpea, indicates that there is a reduction in growth with decreases in water levels and plant density parameter. The highest values occur with irrigation depth of 367.86 mm and density of 188,000 plants ha- 1. Separately, the continuous application of water increased the photosynthetic rate, stomatal conductance and transpiration with reduced values in the smaller irrigation 201.73 mm and 260.39 mm .

Mestrado em Viticultura e Enologia - Instituto Superior de Agronomia / Faculdade de Ciências. Universidade do Porto
The purpose of this work was to compare the effects of four strategies of deficit irrigation and analyse the differences of physiology, vegetative growth, yield and quality of grapes of Alvarinho. The study was performed in 2014, at Quinta da Aveleda, located in the Vinhos Verdes region, in Penafiel. So the following treatments were tested: not watered control (R0), without any intervention; irrigation based on leaf water potential (R1); irrigation with 75% ETc (R2) and irrigation with 100% ETc (R3). The evolution of the basic leaf water potential has shown that the vines were always in water comfort. Irrigation with 100% Etc presented higher total leaf area but didin’t obtain a high production. Regarding the composition of the must in the vintage, the modalities apparently showed similar values, resulting in more efficient use of irrigation water. This was a year with atypical weather conditions, registering a lot of rainfall during the summer months. So the results shouldn’t be extrapolated for future years.

O feijÃo-de-corda à uma cultura muito importante na dieta das camadas sociais inferiores. O baixo rendimento dessa cultura faz com que cada vez mais a irrigaÃÃo venha como ferramenta para auxiliar no aumento da produtividade. PorÃm, com o advento da irrigaÃÃo o problema da salinidade aumentou bastante. Neste trabalho, avaliou-se o acÃmulo de sais no solo e a produtividade do feijÃo-de-corda [Vigna unguiculata (L.) Walp.], cv. Epace 10, em funÃÃo da fraÃÃo de lixiviaÃÃo e da salinidade da Ãgua de irrigaÃÃo. O experimento foi realizado durante a estaÃÃo seca na Ãrea experimental do LaboratÃrio de HidrÃulica e IrrigaÃÃo/UFC, seguindo um delineamento em blocos ao acaso, com quatro tratamentos e cinco repetiÃÃes, sendo que cada parcela consistiu de 4 linhas de plantio com o comprimento de 5,0m. No tratamento 1 as plantas foram irrigadas com Ãgua do poÃo (CEa = 0,8 dS m-1), sem fraÃÃo de lixiviaÃÃo; os tratamentos 2, 3 e 4, consistiram de Ãgua salina com CEa de 5,0 dS m-1, sem fraÃÃo de lixiviaÃÃo, com fraÃÃo de lixiviaÃÃo de 0,14 e 0,28, respectivamente. Durante as fases de floraÃÃo e frutificaÃÃo foram feitas quatro avaliaÃÃes de trocas gasosas foliares e trÃs determinaÃÃes dos teores de Na+, Ca+2, K+ e Cl-. Ao final do ciclo foram determinadas parÃmetros de crescimento vegetativo e reprodutivo, bem como o acumulo de sais no solo. A aplicaÃÃo de Ãgua salina provocou acÃmulo de sais no solo, porÃm esses efeitos foram parcialmente revertidos pelo aumento da fraÃÃo de lixiviaÃÃo; a salinidade reduziu a produtividade de grÃo, porÃm nÃo afetou sua qualidade e provocou um aumento de 10% no Ãndice de colheita; a reduÃÃo na produtividade ocasionada pela salinidade da Ãgua deveu-se, em parte, à reduÃÃo na assimilaÃÃo lÃquida de carbono durante as fases de floraÃÃo e frutificaÃÃo, associada aos efeitos osmÃticos e ao acÃmulo de Ãons potencialmente tÃxicos nos tecidos foliares; as fraÃÃes de lixiviaÃÃo nÃo tiveram muita influÃncia na superaÃÃo dos danos provocados pela salinidade sobre a produtividade das plantas.
The cowpea is a very important crop in the diet of the inferior social classes, but its productivity is very low, especially is non-irrigated areas. However, the irrigation in semi-arid areas has been associated to soil salinization. The study had the objective to evaluate the effect of water salinity and the leaching fraction on the growth and the productivity of grains of cowpea plants (Vigna unguiculata), cv, Epace 10. The experiment was set up in the experimental area of the LaboratÃrio de HidrÃulica e IrrigaÃÃo/UFC, during the dry season. A completely randomized block design, with five repetitions, was adopted. Each experimental unit consisted of 4 lines of plantation of 5.0 m. The treatments studied were:: 1. Well water with ECw of 0.8 dS m-1 (without leaching fraction); 2. saline water with ECw of 5.0 dS m-1 (without leaching fraction); 3. saline water with ECw of 5.0 dS m-1 with leaching fraction of 0.14; and 4. saline water with ECw of 5.0 dS m-1 with leaching fraction of 0.28. During the flowering and fruit development four measurements of gas exchange and three determinations ion concentrations (Na+, Ca+2, K+, and Cl-) were performed. At the end of the crop cycle, some parameters of vegetative growth and plant yield, and salt accumulation in the soil were observed. The saline water application provoked salt accumulation in the soil profile, but this effect was partially reverted by the increase of the leaching fraction. Salinity reduced plant yield, but it did not affect its quality and caused a 10% increase in the harvest index. The reduction in plant yield was related, at least in part, to decrease in net assimilation of carbon during flowering and fruit development due to osmotic effects and to accumulation of potentially toxic ions. In general, the increase in leaching fraction did not reduce the effect of the salinity on plant development.

ASSIS JÚNIOR, José Otacílio de. Produtividade do feijão-de-corda e acúmulo de sais no solo em função da salinidade da água e da fração de lixiviação. 2007. 63 f. Dissertação (Mestrado em engenharia agrícola)- Universidade Federal do Ceará, Fortaleza-CE, 2007.
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The cowpea is a very important crop in the diet of the inferior social classes, but its productivity is very low, especially is non-irrigated areas. However, the irrigation in semi-arid areas has been associated to soil salinization. The study had the objective to evaluate the effect of water salinity and the leaching fraction on the growth and the productivity of grains of cowpea plants (Vigna unguiculata), cv, Epace 10. The experiment was set up in the experimental area of the Laboratório de Hidráulica e Irrigação/UFC, during the dry season. A completely randomized block design, with five repetitions, was adopted. Each experimental unit consisted of 4 lines of plantation of 5.0 m. The treatments studied were:: 1. Well water with ECw of 0.8 dS m-1 (without leaching fraction); 2. saline water with ECw of 5.0 dS m-1 (without leaching fraction); 3. saline water with ECw of 5.0 dS m-1 with leaching fraction of 0.14; and 4. saline water with ECw of 5.0 dS m-1 with leaching fraction of 0.28. During the flowering and fruit development four measurements of gas exchange and three determinations ion concentrations (Na+, Ca+2, K+, and Cl-) were performed. At the end of the crop cycle, some parameters of vegetative growth and plant yield, and salt accumulation in the soil were observed. The saline water application provoked salt accumulation in the soil profile, but this effect was partially reverted by the increase of the leaching fraction. Salinity reduced plant yield, but it did not affect its quality and caused a 10% increase in the harvest index. The reduction in plant yield was related, at least in part, to decrease in net assimilation of carbon during flowering and fruit development due to osmotic effects and to accumulation of potentially toxic ions. In general, the increase in leaching fraction did not reduce the effect of the salinity on plant development.
O feijão-de-corda é uma cultura muito importante na dieta das camadas sociais inferiores. O baixo rendimento dessa cultura faz com que cada vez mais a irrigação venha como ferramenta para auxiliar no aumento da produtividade. Porém, com o advento da irrigação o problema da salinidade aumentou bastante. Neste trabalho, avaliou-se o acúmulo de sais no solo e a produtividade do feijão-de-corda [Vigna unguiculata (L.) Walp.], cv. Epace 10, em função da fração de lixiviação e da salinidade da água de irrigação. O experimento foi realizado durante a estação seca na área experimental do Laboratório de Hidráulica e Irrigação/UFC, seguindo um delineamento em blocos ao acaso, com quatro tratamentos e cinco repetições, sendo que cada parcela consistiu de 4 linhas de plantio com o comprimento de 5,0m. No tratamento 1 as plantas foram irrigadas com água do poço (CEa = 0,8 dS m-1), sem fração de lixiviação; os tratamentos 2, 3 e 4, consistiram de água salina com CEa de 5,0 dS m-1, sem fração de lixiviação, com fração de lixiviação de 0,14 e 0,28, respectivamente. Durante as fases de floração e frutificação foram feitas quatro avaliações de trocas gasosas foliares e três determinações dos teores de Na+, Ca+2, K+ e Cl-. Ao final do ciclo foram determinadas parâmetros de crescimento vegetativo e reprodutivo, bem como o acumulo de sais no solo. A aplicação de água salina provocou acúmulo de sais no solo, porém esses efeitos foram parcialmente revertidos pelo aumento da fração de lixiviação; a salinidade reduziu a produtividade de grão, porém não afetou sua qualidade e provocou um aumento de 10% no índice de colheita; a redução na produtividade ocasionada pela salinidade da água deveu-se, em parte, à redução na assimilação líquida de carbono durante as fases de floração e frutificação, associada aos efeitos osmóticos e ao acúmulo de íons potencialmente tóxicos nos tecidos foliares; as frações de lixiviação não tiveram muita influência na superação dos danos provocados pela salinidade sobre a produtividade das plantas.

Chapter 3 gives examples of how grapevines, being woody perennials, have the potential to develop extensive, deep root systems when soil conditions are favorable. One of the most important factors governing root growth is a soil’s structure, the essential attributes of which are • Spaces (collectively called the pore space or porosity) through which roots grow, gases diffuse, and water flows • Storage of water and natural drainage following rain or irrigation • Stable aggregation • Strength that not only enables moist soil to bear the weight of machinery and resist compaction but also influences the ease with which roots can push through the soil The key attributes of porosity, aeration and drainage, water storage, aggregation, and soil strength are discussed in turn. Various forces exerted by growing roots, burrowing animals and insects, the movement of water and its change of state (e.g., from liquid to ice) together organize the primary soil particles—clay, silt, and sand—into larger units called aggregates. Between and within these aggregates exists a network of spaces called pores. Total soil porosity is defined by the ratio . . . Porosity = Volume of pores/Volume of soil . . . A soil’s A horizon, containing organic matter, typically has a porosity between 0.5 and 0.6 cubic meter per cubic meter (m3/m3)—also expressed as 50% to 60%. In subsoils, where there is little organic matter and usually more clay, the porosity is typically 40% to 50%. Box 4.1 describes a simple way of estimating a soil’s porosity. Total porosity is important because it determines how much of the soil volume water, air, and roots can occupy. Equally important are the shape and size of the pores. The pores created by burrowing earthworms, plant roots, and fungal hyphae are roughly cylindrical, whereas those created by alternate wetting and drying appear as cracks. Overall, however, we express pore size in terms of diameter (equivalent to a width for cracks). Table 4.1 gives a classification of pore size based on pore function.