Top PDF Performance of crisphead lettuce cultivars under protected environment in different times of production

Performance of crisphead lettuce cultivars under protected environment in different times of production

Performance of crisphead lettuce cultivars under protected environment in different times of production

The objective of this work was to evaluate the behavior of Crisphead lettuce as a function of production seasons under different forms of protected environment. Two experiments were carried out in the field at different times: September to December 2017 and June to August 2018, in a randomizaed blocks desing, in a 4 x 7 factorial scheme, the first one being production environments under shade nets: red screen, chromatinet ® screen, black screen and full sun, and the second, lettuce cultivars: Winslow, Irene, Balsamo, Rafaela, Iron Wood, Great Lakes and Delícia. The harvest was carried out at forty-two days after transplanting, where the following variables were analyzed: stem length (cm), total production and commercial productivity (t.ha -1 ). The data were submitted to analysis of variance, and a joint analysis was performed to analyze the treatments effect, then the means were compared by the Scott-Knott test, at 5% probability. The microclimate was altered in the shaded beds, which affected the cultivars development. The cultivation in protected environment provides higher productivity of Crisphead lettuce from September to December, at that time the cultivars Balsamo and Delicia were highlighted under chromatinet ® . In the period of mild temperatures, a better performance was observed for cv. Balsamo in full sun.
Mostrar mais

9 Ler mais

Bell pepper production under saline stress and fertigation with different K+/Ca2+ ratios in a protected environment

Bell pepper production under saline stress and fertigation with different K+/Ca2+ ratios in a protected environment

These results agreed with those reported by various authors who studied the bell pepper crop under saline stress conditions, cultivated in either soil (Leonardo et al., 2007; Lima et al., 2016) or substrate (Arruda et al., 2011; Rubio et al., 2011; Nunes et al., 2013; Furtado et al., 2017; Lima et al., 2017). Reductions in fruit size and weight due to saline stress and, consequently, in the economic performance of the crop, are caused by physiological and biochemical changes in the cells or at the molecular level (Munns & Tester, 2008).
Mostrar mais

11 Ler mais

GREENHOUSE CRISPHEAD LETTUCE GROWN WITH MULCHING AND UNDER DIFFERENT SOIL WATER TENSIONS

GREENHOUSE CRISPHEAD LETTUCE GROWN WITH MULCHING AND UNDER DIFFERENT SOIL WATER TENSIONS

As lettuce is a short-cycle and rapid-growth vegetable, it is very demanding in terms of climate conditions, water and nutrients supply; however, it provides fresh mass in rapid increments throughout its cycle. The strengthening of these needs can be better administered by cultivation in protected environments, in which vegetables can achieve outstanding productions with excellent product quality. It happens because these environments provide a more propitious climate for crop development throughout the year, lessen problems with pests and diseases, protect against climate changes, lower leaching and reduce fertilization costs, enabling thus greater production compared to open environments. However, it is of upmost importance the use of irrigation to reach highest yields (OLIVEIRA et al., 2011).
Mostrar mais

9 Ler mais

Costs, viability and risks of organic tomato production in a protected environment

Costs, viability and risks of organic tomato production in a protected environment

ABSTRACT - The aim of this research was to evaluate the agro-economic performance of two table-tomato cultivars (Santa Clara and Siluet), under organic cultivation and in a protected environment. Through the analysis of production costs, economic viability and project risk, it was sought to generate a proposal for agricultural profitability having less socio-environmental impact on family farming. To achieve that, the Operating and Total Production Costs, Net Present Value (NPV) and Internal Rate of Return (IRR) were calculated. A sensitivity analysis and economic risk analysis were then carried out. Both cultivars under consideration presented satisfactory economic indicators for the period being analysed. Judging by the criterion of Net Present Value, almost all discount rates (except for the rates of 10 and 12% for the Santa Clara cultivar) were found to be economically viable, with internal rates of return higher than the annual rate of 6%, the minimum rate of financial attractiveness considered. The sensitivity analysis revealed that price received and productivity have the greatest interference on project profitability, followed by packaging and labour costs. The estimated economic risk was relatively low, with a probability of obtaining a negative NPV of 30.31% in the case of the ‘Santa Clara’, and 4.48% for the ‘Siluet’. It is therefore concluded that the organic production of ‘Siluet’ and ‘Santa Clara’ tomatoes under protected cultivation is an economically viable activity, with emphasis on the agro-economic superiority of the Siluet cultivar. Key words: Solanum lycopersicum. Management. Economy. Sustainability.
Mostrar mais

8 Ler mais

AGRONOMIC PERFORMANCE OF SINGLE HEAD BROCCOLI CULTIVARS UNDER PROTECTED ENVIRONMENT IN TROPICAL CONDITIONS

AGRONOMIC PERFORMANCE OF SINGLE HEAD BROCCOLI CULTIVARS UNDER PROTECTED ENVIRONMENT IN TROPICAL CONDITIONS

In this study it was verified cycle means of 111 days, based on the four cultivars object of study, and to curd emission the time required by the culture was of 96.52 days. These values observed are so important to knowledge of the culture and better applicability in the production systems. Farnham & Bjorkman (2010), analyzing abiotic stresses concluded that temperature affect its cycle and yield. This information can be confirmed when verifying the great variation of results found in this study when compared to other authors.
Mostrar mais

12 Ler mais

Costs, viability and risks of organic tomato production in a protected environment

Costs, viability and risks of organic tomato production in a protected environment

ABSTRACT - The aim of this research was to evaluate the agro-economic performance of two table-tomato cultivars (Santa Clara and Siluet), under organic cultivation and in a protected environment. Through the analysis of production costs, economic viability and project risk, it was sought to generate a proposal for agricultural profitability having less socio-environmental impact on family farming. To achieve that, the Operating and Total Production Costs, Net Present Value (NPV) and Internal Rate of Return (IRR) were calculated. A sensitivity analysis and economic risk analysis were then carried out. Both cultivars under consideration presented satisfactory economic indicators for the period being analysed. Judging by the criterion of Net Present Value, almost all discount rates (except for the rates of 10 and 12% for the Santa Clara cultivar) were found to be economically viable, with internal rates of return higher than the annual rate of 6%, the minimum rate of financial attractiveness considered. The sensitivity analysis revealed that price received and productivity have the greatest interference on project profitability, followed by packaging and labour costs. The estimated economic risk was relatively low, with a probability of obtaining a negative NPV of 30.31% in the case of the ‘Santa Clara’, and 4.48% for the ‘Siluet’. It is therefore concluded that the organic production of ‘Siluet’ and ‘Santa Clara’ tomatoes under protected cultivation is an economically viable activity, with emphasis on the agro-economic superiority of the Siluet cultivar.
Mostrar mais

8 Ler mais

Qualitative performance of lettuce cultivars in four seasons in Mossoró, Rio Grande do Norte State, Brazil

Qualitative performance of lettuce cultivars in four seasons in Mossoró, Rio Grande do Norte State, Brazil

was a different behavior from the one observed in this study for cultivars of the same lettuce group, where the highest values of titratable acidity values were found in autumn and winter and the lowest values in summer and spring. This can be explained by the difference in climate conditions between the regions in the study, with maximum temperatures of up to 38.87°C in autumn and low relative humidity of 45.76% (Figure 1). These values are different from those observed in Minas Gerais state, which has a milder climate with average annual temperature of 21°C (Pizolato Neto et al., 2011), evidencing that chemical composition of plants can vary according to the cultivar
Mostrar mais

10 Ler mais

Hydroponic lettuce production in different concentrations and flow rates of nutrient solution

Hydroponic lettuce production in different concentrations and flow rates of nutrient solution

additivated with 5% light diffusor and 150 micron thickness and lateral parts protected with white anti-aphid screen (mesh= 0.64 x 0.20 mm). The maximum and the minimum temperatures were registered daily, as well as the air relative humidity (UR) inside the greenhouse, at 9 a.m. and 3 p.m., using maximum and minimum thermometers and a direct reading hygrometer. The average of maximum and minimum temperatures (°C) and UR% were 32.3; 18.6 and 59.1, respectively, for the period when the experiment was in progress.

5 Ler mais

Performance of sunflower cultivars at different seeding periods in central Brazil

Performance of sunflower cultivars at different seeding periods in central Brazil

Sunflower (Helianthus annuus L.) is a very important crop for Brazil, and especially for Chapada do Parecis which is the largest domestic producer, because of its climate and soil conditions are adequate to the development of the specie. The performance of cultivars and sunflower seed sowing periods were evaluated in Central Brazil. Experimental design comprised an 8 x 5 factorial randomized complete block, with eight sunflower cultivars (Aguará 06, Aguará 04, MG 305, CF 101, SYN 3950HO, SYN 045, GNZ NEON and HELIO 251) and five decennial seeding periods, with three replicates. Analysis of variance and Scott-Knott´s test (p<0.05) were applied. Cultivars GNZ NEON and SYN 045 provide the highest production rates in achenes, with higher value in favor of GNZ NEON. SYN 3950HO (this with higher value), CF101, MG 305, SYN 045 and Aguará 04 gets the highest oil rates in the achenes, with SYN 045, GNZ NEON, Aguará 04, CF101 and SYN 3950HO with the highest oil production. The first seed sowing period is the most productive and the first and fifth periods have the best results for oil productivity. Cultivar GNZ NEON and the first period exceede the others with regard to vegetative and reproductive variables. Index terms: Agronomic characteristics; varietal performance; planting date; Helianthus annuus; plant productivity.
Mostrar mais

10 Ler mais

Performance of juice and wine grape cultivars in different training systems

Performance of juice and wine grape cultivars in different training systems

the CD training system, no statistical difference was observed between Isabel Precoce and Isabel cultivars, which presented the highest soluble solids content, respectively 17.7 and 17.6 °Brix, while for BRS Violeta and Concord cultivars, which did not show averages differing statistically, values were 16.5 and 16.7 °Brix. For training systems with higher number of bunches, Borges et al. (2014) observed soluble solids content of 12.4 °Brix for Concord cultivar in pergola; Ribeiro et al. (2012) of 21.0 °Brix for Isabel Precoce cultivar in trellis system and Sato et al., (2009) 16.7 °Brix for Isabel cultivar in the Geneva Double Curtain system. Values obtained by Ribeiro et al. (2012) were higher because vines were cultivated in Petrolina-PE, where water and thermal conditions, favor the accumulation of sugars in grapes. However, the differences found by the various authors are probably due to the climatic differences among production sites and harvest year, because when grape maturation and harvest coincides with a less rainy period, the process is favored, allowing greater accumulation of sugars in grapes (SANTOS et al., 2011; REGINA et al., 2011).
Mostrar mais

8 Ler mais

PRODUCTION OF BARUZEIRO SEEDLING IN DIFFERENT PROTECTED ENVIRONMENTS AND SUBSTRATES EDILSON COSTA

PRODUCTION OF BARUZEIRO SEEDLING IN DIFFERENT PROTECTED ENVIRONMENTS AND SUBSTRATES EDILSON COSTA

ABSTRACT: The high seedlings quality is essential for deployment of homogeneous orchards. This study evaluated the baruzeiro (Dipteryx alata Vog) seedlings formation on different substrates within protected environments. It was used substrates with100% of cattle manure; 100% of cassava stems; 100% of vermiculite; 50% of cattle manure + 50% of cassava stems; 50% of cattle manure + 50% of vermiculite; 50% of cassava stems + 50% of vermiculite; and + ⅓ of cattle manure + ⅓ of cassava stems + ⅓ of vermiculite. These substrates were tested in protected areas: greenhouse; black shade net of 50% shading; and aluminized thermo-reflective screen of 50% shading. A completely randomized experimental design with five replicates of four plants was adopted. Initially, data were submitted to analysis of individual variance of the substrates, in each environment of cultivation, then performing the evaluation of the residual mean square and the analysis of these environments together for comparison. The best substrate for baruzeiro seedlings was pure vermiculite. The substrates with 100% of manure and the substrate with 33.33% of the mixed studied materials can be used for seedlings formation. The environment with screen can be indicated for the production of baruzeiro seedlings, since it gave vigor to the seedlings.
Mostrar mais

9 Ler mais

Evapotranspiration of rose cultivated in protected environment

Evapotranspiration of rose cultivated in protected environment

The objective of this study was to determine the evapotranspiration and crop coefficient for the cut rose (cv. Carola) cultivated in protected environment and the coefficient of small tank installed inside the greenhouse during the period of one year. Five rows of plants were planted with spacing of 1.20 m between rows and 0.20 m between plants. Each line consisted of five plots with five plants per plot. Plants of the second and fourth rows and of the second and fourth plots were installed in four drainage lysimeters with dimensions of 1.20 x 1.20 x 0.80 m. The plants of the remaining plots were considered as border plants. A drip irrigation system was used. An automatic weather station was installed in the greenhouse and the data were collected and stored daily at an interval of one hour in a data-logger. The crop coefficient (Kc) showed mean values of 0.75 in the vegetative phase and 1.18 during the productive phase. The small pan (tank) coefficient (Ktr) was 0.72.
Mostrar mais

8 Ler mais

Variability, plot size and border effect in lettuce trials in protected environment

Variability, plot size and border effect in lettuce trials in protected environment

ABSTRACT: The variability within rows of cultivation may reduce the accuracy of experiments conducted in a complete randomized block design if the rows are considered as blocks, however, little is known about this variability in protected environments. Thus, our aim was to study the variability of the fresh mass in lettuce shoot, growing in protected environment, and to verify the border effect and size of the experimental unit in minimizing the productive variability. Data from two uniformity trials carried out in a greenhouse in autumn and spring growing seasons were used. In the statistical analyses, it was considered the existence of parallel cultivation rows the lateral openings of the greenhouse and of columns perpendicular to these openings. Different scenarios were simulated by excluding rows and columns to generate several borders arrangements and
Mostrar mais

13 Ler mais

Performance of blueberry cultivars under mild winter conditions

Performance of blueberry cultivars under mild winter conditions

Studies that relate ratio with acceptability of blueberry fruits are rather scarce and according to SAFTNER et al. (2008) the acceptability of fruits is best related to flavor, succulence, sweetness and appearance than with instrumental measurements. However, BEAUDRY (1992) mentions that a blueberry ratio between 10 and 33 indicates that the fruit displays good quality. ‘Climax’ stood out in the 2013/2014 cycle with high soluble solids content and low acidity, reaching a ratio of 20.57. However, in the next cycle, because of the high acidity (1.28%), it was ranked among the cultivars with smaller ratio (8.89). Acid value was much higher than reported by GÜNDÜZ et al. (2015), who reported 0.27% for this cultivar in the region of Manor-Georgia (EUA), while the ratio reached was 48.6. The difference between the years may be related to climatic factors, as in the second cycle the cultivars generally showed an increase in acidity and reduction of the ratio. In the second cycle, the harvest took place in November, which was rainier and had lower temperatures than December of the previous year (Table 2).
Mostrar mais

8 Ler mais

MINERAL NUTRITION OF CRISPHEAD LETTUCE GROWN IN A HYDROPONIC SYSTEM WITH BRACKISH WATER

MINERAL NUTRITION OF CRISPHEAD LETTUCE GROWN IN A HYDROPONIC SYSTEM WITH BRACKISH WATER

ABSTRACT - Water availability in the Brazilian semiarid is restricted and often the only water source available has high salt concentrations. Hydroponics allows using these waters for production of various crops, including vegetables, however, the water salinity can cause nutritional disorders. Thus, two experiments were conducted in a greenhouse at the Department of Agricultural Engineering of the Federal Rural University of Pernambuco, to evaluate the effects of salinity on the mineral nutrition of crisphead lettuce, cultivar Taina, in a hydroponic system (Nutrient Film Technique), using brackish water in the nutrient solution, which was prepared by adding NaCl to the local water (0.2 dS m -1 ). A randomized blocks experimental design was used in
Mostrar mais

9 Ler mais

Variability, plot size and border effect in lettuce trials in protected environment

Variability, plot size and border effect in lettuce trials in protected environment

Protected environments may be as, or more hetero- geneous as natural environments due to the variation in micrometeorological conditions that may occur within the protected environment, provided by its specific structural characteristics (Santos et al. 2010; Lúcio et al. 2011). In addition, characteristics inherent to horticultural crops such as the presence or absence of fruits suitable for harvesting, the multiple harvests that are carried out in some crops, and the more intensive cultural management in relation to other crops, are additional sources of variability (Lorentz et al. 2005; Lúcio et al. 2008). Thus, in this type of experiment, often strategies to reduce experimental error such as the use of concomitant observations, adequate experimental design, selection of the experimental unit size and shape, choice of sample size and number of replications cannot be used due to space limitations, or even when used, satisfactory results are not obtained. In these cases, the experiments do not present the necessary precision in order to adequately identify the differences between treatments.
Mostrar mais

13 Ler mais

PERFORMANCE OF TREATED SEEDS OF DIFFERENT SOYBEAN CULTIVARS IN FUNCTION OF ENVIRONMENTS AND STORAGE PERIODS

PERFORMANCE OF TREATED SEEDS OF DIFFERENT SOYBEAN CULTIVARS IN FUNCTION OF ENVIRONMENTS AND STORAGE PERIODS

The objective of this study was to evaluate the performance of seeds of different soybean cultivars treated in function of environments and storage periods, at Alto Garças, State of Mato Grosso, Brazil. The experimental design was completely randomized in 2 x 5 x 6 factorial design (controlled temperature and RH conditions, 10 ºC with 50% RH and at room temperature) five storage periods: 0, 2, 4, 6, and 8 months; seeds from six soybean cultivars (TMG 1176, TMG 1179, TMG 115, TMG 132, TMG 133, and GB 874) were used for the following determinations: germination, accelerated aging, electrical conductivity, cold test, and seedling emergence. Seeds of soybean cultivars treated with insecticide (Imidacloprid + Thiodicarb) and fungicide (Carboxin + Thiram) stored under controlled temperature and relative humidity conditions maintain the physiological quality for eight months of storage. At room temperature conditions storaged at Alto Garças, MT, the deterioration rate of seeds treated with insecticide (Imidacloprid + Thiodicarb) and fungicide (Carboxin + Thiram) is accentuated after six months of storage.
Mostrar mais

17 Ler mais

Production of laying hens in different rearing systems under hot weather

Production of laying hens in different rearing systems under hot weather

The heat loss in birds is through the blood flow in the body surface, modifying the respiratory tract (Abreu, Abreu, Coldebella, Jaenish, & Paiva, 2007), so when birds are under heat stress they remain part of the time with the beak open. Birds try to perform an energy exchange with the environment, making physiological adjustments essential for the maintenance of thermal equilibrium (Silva, 2008).

6 Ler mais

Sensory quality attributes of lettuce obtained using different harvesting performance systems

Sensory quality attributes of lettuce obtained using different harvesting performance systems

The objective of this study was to determine the best lettuce cultivar (American ‘Graciosa’, ‘Vanda’, ‘Marcela’ and ‘Lavínia’) harvesting method. Therefore, quality and shelf-life were evaluated using sensory analyses. Lettuce heads was harvested with the root on by the producer, so that they were cut in different ways in the laboratory. The samples were stored in a cold chamber at 10 °C and 80% ± 2% of relative humidity for nine days, and the sensorial analyses were performed according to Qualitative Descriptive Analysis method on days 1, 3, 6, and 9 of storage by twelve trained testers. The results were evaluated by variance analysis, principal component analysis, and the Tukey test with a reliability of 95%. The results indicate that there was a reduction in the quality of lettuce between the 1 st and the 5 th day of storage and that after the sixth day of storage the lettuce samples were
Mostrar mais

6 Ler mais

EFFECT OF PURPLE LETTUCE AQUEOUS EXTRACT IN CYTOGENETICS ACTIVITY OF LETTUCE ROOT UNDER SALT STRESS

EFFECT OF PURPLE LETTUCE AQUEOUS EXTRACT IN CYTOGENETICS ACTIVITY OF LETTUCE ROOT UNDER SALT STRESS

Abstract : Salinity can affect cell division, causing cytotoxicity, which can lead to inhibition of the mitotic index or chromosomal abnormalities such as the formation of micronuclei, chromosome stickiness, c-mitosis and multipolar anaphases. Plants react to salt stress with biochemical, physiological, cellular adjustments and activate enzymatic and non-enzymatic antioxidative defense mechanisms. Purple lettuce is rich in anthocyanins, compounds that give it high antioxidant activity helping to defend the plant from de salt stress. The aim of this study was to evaluate the effect of different leaf extract concentrations of purple lettuce on the cytogenetic activity of lettuce roots, cv. Regina, from seeds subjected to salt stress. Four extract concentrations of purple lettuce (0, 50, 100 and 150 g lettuce leaves L-1 water) and five concentrations of sodium chloride (0, 30, 60, 90 and 120 mM) were tested, constituting 20 treatments, with distilled water for a negative control. The analyses were of mitotic index (MI), phase index of mitosis (prophase, metaphase, anaphase and telophase) and the presence of chromosomal aberrations. Salt reduces the mitotic index and all index phases of the lettuce roots. The purple lettuce extract does not affect the mitotic index, reduces the cell index in prophase and increases the cells in telophase of lettuce roots. The purple lettuce extract and salt cause chromosomal abnormalities in lettuce root cells; however, a smaller number of mutations is found by applying 100 g L-1 extract.
Mostrar mais

14 Ler mais

Show all 10000 documents...

temas relacionados