scholarly journals Photo-selective shading screens as a cover for production of purple lettuce

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Ramon Amaro de Sales ◽  
Evandro Chaves de Oliveira ◽  
Eduardo Buzatto ◽  
Robson Ferreira de Almeida ◽  
Marcus José Alves de Lima ◽  
...  
Keyword(s):  
Abiotic Stress ◽  
Phenolic Compounds ◽  
Dry Matter ◽  
Physiological Responses ◽  
Stem Length ◽  
Cultivation Conditions ◽  
Fresh Matter ◽  
Protected Cultivation ◽  
Cultivation Practices ◽  
Chlorophyll Index

AbstractPhoto-selective shading screens are emerging practices that aim to combine crop physical protection with different solar radiation filtration to achieve desired physiological responses. The objective of the present study was to evaluate the effect of photo-selective shading screens on the growth and physiology of purple lettuce for two transplanting seasons in tropical climate in Brazil. A 2 × 4 factorial arrangement was used, being considered the first factor, the transplanting season (spring and fall), and the second factor is the three 35% shading photo-selective shading screens (red, black and silver) and full sun control. The experimental design was a randomized complete block with four replications. The variables studied were: total fresh matter, total dry matter, leaf number, stem diameter, stem length, leaf area, SPAD chlorophyll index, nitrogen balance indexes, chlorophyll, flavonoids and anthocyanins. The photo-selective shading screens influenced the microclimate and the growth variables of purple lettuce, mainly when these plants were sown in the fall. Planting lettuce during spring may result in lower yields due to the higher investment of plants in secondary metabolites to defend against abiotic stress. According to the results, photo-selective shading screens are an appropriate agronomic technique to reduce phenolic compounds and improve lettuce cultivation conditions and can be implemented within protected cultivation practices to improve crop performance.

scholarly journals PERFORMANCE OF LETTUCE SUBMITTED TO THE ROCK DUST REMINERALIZER AND DOSES OF EFFICIENT MICROORGANISMS

2021 ◽  
Vol 8 (2) ◽  
pp. e5526
Author(s):  
Westefann Dos Santos Sousa ◽  
Thiago Souza Campos ◽  
Ane Gabriele Vaz Souza ◽  
Pedro Henrique Nascimento Cintra ◽  
Layanara Oliveira Faria ◽  
...  
Keyword(s):  
Stem Length ◽  
Cultivated Plants ◽  
Cultivation Conditions ◽  
Fresh Matter ◽  
Iceberg Lettuce ◽  
Number Of Leaves ◽  
Lettuce Cultivar ◽  
Stem Leaf ◽  
Different Doses ◽  
Rock Dust

The use of soil remineralizers with efficient microorganisms (EM) can represent an effective and sustainable alternative to improve the growth, development, and yield of cultivated plants. Thus, the present study aimed to evaluate the effect of different doses of EM, in the presence or absence of rock dust (RD), on the development of iceberg lettuce, cultivar Lucy Brown. The design used was completely randomized, arranged in a 2 x 5 factorial scheme, with four replications. The treatments consisted of the presence and absence of RD in the substrate composition, combined with five commercial product doses based on EM (0, 2, 4, 6, and 8 L ha-1). At 30 days after transplanting, root and stem length, head circumference, the number of leaves, stem diameter, leaf area, fresh matter of root, stem, leaf, and shoot, and dry matter of root, stem, leaf, and shoot were evaluated. There was an interaction between the factors for most variables of economic importance. The dose of 4.5 L ha-1 of the product based on EM, combined with PR, implied the best performance of iceberg lettuce under the studied cultivation conditions.

scholarly journals Avaliação fenoprodutiva e teores clorofilianos de rabanete sob fertilização com urina de vaca e cobertura morta

2018 ◽  
Vol 1 (42) ◽  
pp. 31
Author(s):  
Francisco De Assis Bezerra Junior ◽  
José Lucínio De Oliveira Freire ◽  
Jandeilson Alves De Arruda ◽  
Thiago Anderson Oliveira de Azevedo ◽  
Luana Apoena Dantas
Keyword(s):  
Leaf Area ◽  
Specific Leaf Area ◽  
Dry Matter ◽  
Growth Yield ◽  
Plant Production ◽  
Fresh Matter ◽  
Area Index ◽  
Tuberous Roots ◽  
Cow Urine ◽  
Chlorophyll Index

The radish (Raphanus sativus L.) is a short-cycle vegetable that has a rapid demand for nutrients to grow and produce. Because of the small number of reports on organic fertilization with this crop, this work was conducted in the Plant Production Sector of the Course of Agroecology of the Picuí Campus ,IFPB and aimed to evaluate the attributes of growth, yield and chlorophyll index of radish in response to the application of cow urine, via soil, as an alternative fertilization. The experimental design was organized in randomized blocks, with four replications, in a 6 x 2 factorial arrangement, which corresponded to six concentrations of cow urine (0.00%, 0.25%, 0.50%, 0.75%, 1 , 00% and 1,25% - v / v), applied weekly with and without mulch. The variables analyzed were plant height, number of leaves, leaf area, specific leaf area, leaf area index, Falker a, b and total chlorophyll index, longitudinal and equatorial diameters of tuberous roots, fresh tuberous root mass, Axial root length, total dry mass, percentage of commercial tuberous roots, productivity and dry matter yield. The use of mulch reduced specific leaf area, fresh matter and radish productivity, regardless of the concentration of cow urine applied. The leaf chlorophyll index of radish was higher in the plants without mulching. Longer radishes were obtained on substrates without mulching or 0.51% cow urine. Possibly, due to the production of secondary metabolites (allelochemicals) from the mulch (rice straw), the application of 0.54% cow urine without mulching provided higher radish productivity. The concentration of cow urine of 0.38% provided higher yields of dry matter.

scholarly journals Early prediction of biomass in hybrid rye based on hyperspectral data surpasses genomic predictability in less-related breeding material

2021 ◽  
Vol 134 (5) ◽  
pp. 1409-1422
Author(s):  
Rodrigo José Galán ◽  
Angela-Maria Bernal-Vasquez ◽  
Christian Jebsen ◽  
Hans-Peter Piepho ◽  
Patrick Thorwarth ◽  
...  
Keyword(s):  
Dry Matter ◽  
Genetic Relatedness ◽  
Snp Array ◽  
Matter Content ◽  
Hyperspectral Data ◽  
Winter Rye ◽  
Dry Matter Content ◽  
Early Prediction ◽  
Bivariate Model ◽  
Fresh Matter

Abstract Key message Hyperspectral data is a promising complement to genomic data to predict biomass under scenarios of low genetic relatedness. Sufficient environmental connectivity between data used for model training and validation is required. Abstract The demand for sustainable sources of biomass is increasing worldwide. The early prediction of biomass via indirect selection of dry matter yield (DMY) based on hyperspectral and/or genomic prediction is crucial to affordably untap the potential of winter rye (Secale cereale L.) as a dual-purpose crop. However, this estimation involves multiple genetic backgrounds and genetic relatedness is a crucial factor in genomic selection (GS). To assess the prospect of prediction using reflectance data as a suitable complement to GS for biomass breeding, the influence of trait heritability ($$H^{2}$$ H 2 ) and genetic relatedness were compared. Models were based on genomic (GBLUP) and hyperspectral reflectance-derived (HBLUP) relationship matrices to predict DMY and other biomass-related traits such as dry matter content (DMC) and fresh matter yield (FMY). For this, 270 elite rye lines from nine interconnected bi-parental families were genotyped using a 10 k-SNP array and phenotyped as testcrosses at four locations in two years (eight environments). From 400 discrete narrow bands (410 nm–993 nm) collected by an uncrewed aerial vehicle (UAV) on two dates in each environment, 32 hyperspectral bands previously selected by Lasso were incorporated into a prediction model. HBLUP showed higher prediction abilities (0.41 – 0.61) than GBLUP (0.14 – 0.28) under a decreased genetic relationship, especially for mid-heritable traits (FMY and DMY), suggesting that HBLUP is much less affected by relatedness and $$H^{2}$$ H 2 . However, the predictive power of both models was largely affected by environmental variances. Prediction abilities for DMY were further enhanced (up to 20%) by integrating both matrices and plant height into a bivariate model. Thus, data derived from high-throughput phenotyping emerges as a suitable strategy to efficiently leverage selection gains in biomass rye breeding; however, sufficient environmental connectivity is needed.

scholarly journals 267 Supplementing Ca salts of soybean oil to late-gestating beef cows: Impacts on performance and physiological responses of the offspring

2020 ◽  
Vol 98 (Supplement_4) ◽  
pp. 192-192
Author(s):  
Alice Brandão ◽  
Reinaldo F Cooke ◽  
Kelsey Schubach ◽  
Bruna Rett ◽  
Osvaldo Souza ◽  
...  
Keyword(s):  
Soybean Oil ◽  
Dry Matter ◽  
Body Condition Score ◽  
Physiological Responses ◽  
Average Daily Gain ◽  
Plasma Concentrations ◽  
Beef Cows ◽  
Late Gestation ◽  
Muscle Area ◽  
Matter Basis

Abstract This experiment compared performance and physiological responses of the offspring from cows supplemented with Ca salts of soybean oil (CSSO) or prilled saturated fat (CON) during late gestation. Non-lactating, pregnant Angus × Hereford cows (n = 104) that conceived during the same fixed-time artificial insemination protocol, using semen from 2 sires, were used in this experiment. Cows were ranked by pregnancy sire, body weight (BW), and body condition score (BCS). On d 180 of gestation (d -15), cows were randomly assigned to receive (dry matter basis) 415 g of soybean meal per cow daily in addition to 1) 195 g/cow daily of CSSO (n = 52) or 2) 170 g/cow daily of CON (n = 52). Cows were maintained in 2 pastures (26 cows/treatment per pasture), and received daily 12.7 kg/cow (dry matter basis) of grass-alfalfa hay. From d 0 until calving, cows were segregated into 1 of 24 feeding pens thrice weekly and received treatments individually. Cow BW and BCS were recorded, and blood samples were collected on d -15 of the experiment and within 12 h after calving. Calf BW was also recorded and blood sample collected within 12 h of calving. Calves were weaned on d 290 of the experiment, preconditioned for 35 d (d 291 to 325), and transferred to a feedyard where they remained until slaughter. Upon calving, CSSO cows and calves had greater (P < 0.01) plasma concentrations of linoleic acid and total ω - 6 FA compared with CON cohorts. No differences in calf birth BW, weaning BW, and final preconditioning BW were noted (P ≥ 0.36) between treatments. Average daily gain and final BW in the feedlot were greater (P ≤ 0.05) in steers from CSSO cows compared with CON. The incidence of calves diagnosed with BRD that required a second antimicrobial treatment was less (P = 0.03) in calves from CSSO cows, resulting in reduced (P = 0.05) need of treatments to regain health compared with CON (Table 5). Upon slaughter, longissimus muscle area was greater (P = 0.03) in calves from CSSO cows compared with CON. Collectively, these results suggest that supplementing CSSO to late-gestating beef cows stimulated programming effects on postnatal offspring growth and Page 2 of 15 For Peer Review health. Therefore, supplementing late-gestating beef cows with CSSO appears to optimize offspring welfare and productivity in beef production systems.

Wetting and the physiological responses of grain-fed cattle in a heated environment

2004 ◽  
Vol 55 (3) ◽  
pp. 253 ◽  
Author(s):  
John B. Gaughan ◽  
M. Shane Davis ◽  
Terry L. Mader
Keyword(s):  
Heat Stress ◽  
Experimental Design ◽  
Rectal Temperature ◽  
Environmental Conditions ◽  
Dry Matter ◽  
Physiological Responses ◽  
Dry Matter Intake ◽  
Metabolic Responses ◽  
Hot Days ◽  
Carry Over

A controlled crossover experimental design was used to determine the effect of altered water sprinkling duration on heifers subjected to heat stress conditions. Heifers were subjected to 3 days of thermoneutral conditions followed by 3 days of hot conditions accompanied by water sprinkling between 1300 and 1500 h (HOT1–3). Then on the following 2 days (HOT4–5), environmental conditions remained similar, but 3 heifers were sprinkled between 1200 and 1600 h (WET) and 3 were not sprinkled (NONWET). This was followed by a 1-day period (HOT6) in which environmental conditions and sprinkling regimen were similar to HOT1–3. Rectal temperature (RT) was collected hourly, and respiration rate (RR) was monitored every 2 h on HOT Days 2, 4, 5, and 6. Dry matter intake and rate of eating were also determined. Sprinkling reduced RR and RT (P < 0.01) of all heifers during HOT1–3. During HOT4–5, WET heifers had lower (P < 0.05) RT than NONWET from 1300 to 700 h and lower RR from 1400 to 2000 h. Dry matter intake of NONWET heifers was reduced by 30.6% (P < 0.05) during HOT4–5 and by 51.2% on HOT6. On HOT4–5 the dry matter intakes of WET heifers were similar to intakes under thermoneutral conditions. During HOT6, RT was again reduced following sprinkling in all heifers. Comparison of RT and RR of NONWET and WET heifers on HOT1–3 v. HOT6 revealed that under similar environmental conditions, NONWET heifers had increased RT, partially due to carry-over from HOT4–5. However, NONWET heifers had 40% lower feed intake but tended to have lower RR on HOT6 v. HOT1–3. Only RR of WET heifers was greater on HOT6, possibly a result of switching from a 4-h back to a 2-h sprinkling period, while maintaining a 62% greater intake (5.80 v. 3.58 kg/day) than NONWET heifers during this time. Results suggest that inconsistent cooling regimens may increase the susceptibility of cattle to heat stress and elicit different physiological and metabolic responses.

scholarly journals Photosynthesis rate, chlorophyll content and initial development of physic nut without micronutrient fertilization

2013 ◽  
Vol 37 (5) ◽  
pp. 1334-1342 ◽  
Author(s):  
Elcio Ferreira dos Santos ◽  
Bruno José Zanchim ◽  
Aline Grella de Campos ◽  
Raphael Florencio Garrone ◽  
José Lavres Junior
Keyword(s):  
Chlorophyll Content ◽  
Photosynthetic Rate ◽  
Dry Matter ◽  
Complete Solution ◽  
Physiological Responses ◽  
Dry Matter Production ◽  
Physic Nut ◽  
Initial Development ◽  
Cu Deficiency ◽  
Matter Production

Few studies in Brazil have addressed the need for micronutrients of physic nut focusing on physiological responses, especially in terms of photosynthesis. The objective of this study was to evaluate the effects of omission of boron (B), copper (Cu), iron (Fe), manganese (Mn) and zinc (Zn) on Jatropha curcas L.. The experimental design was a randomized block with four replications. The treatments were complete solution (control) and solution without B, Cu, Fe, Mn, and Zn. We evaluated the chlorophyll content (SPAD units), photosynthetic rate, dry matter production and accumulation of micronutrients in plants, resulting from different treatments. The first signs of deficiency were observed for Fe and B, followed by Mn and Zn, while no symptoms were observed for Cu deficiency. The micronutrient omission reduced the dry matter yield, chlorophyll content and photosynthetic rate of the plants differently for each omitted nutrient. It was, however, the omission of Fe that most affected the development of this species in all parameters evaluated. The treatments negatively affected the chlorophyll content, evaluated in SPAD units, and the photosynthetic rate, except for the omission of B. However this result was probably due to the concentration effect, since there was a significant reduction in the dry matter production of B-deficient plants.

scholarly journals Floristic composition and growth of weeds under custard apple (Annona squamosa) progenies

2004 ◽  
Vol 22 (4) ◽  
pp. 529-537 ◽  
Author(s):  
P.S.L. Silva ◽  
Z. Barbosa ◽  
O.F. Oliveira ◽  
R.P. Antonio ◽  
P.I.B. Silva
Keyword(s):  
Leaf Area ◽  
Dry Matter ◽  
Management Practices ◽  
Block Design ◽  
Floristic Composition ◽  
Negative Influence ◽  
Weed Species ◽  
Fresh Matter ◽  
Custard Apple ◽  
Root Collar

Weeds have a negative influence on several fruit tree characteristics, such as yield, making it difficult to management practices in orchards. Alternative weed management methods, aiming to reduce the use of herbicides, have become attractive since herbicides are costly and cause environmental degradation. The use of cultivars with greater competitive ability against weeds has attracted international attention. The objective of this work was to evaluate the floristic composition and growth of weeds under the canopies of irrigated custard apple tree progenies. Twenty halfsibling progenies around three years of age were evaluated in a random block design with five replicates and four plants per plot. A circle with a 0.5 m² area was established around the trunk of each plant. Floristic composition, fresh matter, and dry matter mass of the above-ground part of the weeds, were evaluated in this area. Root collar and canopy diameters, as well as leaf area of the progenies were also evaluated. Fifty-eight weed species were recorded. The five weed families with the most species were Leguminosae, Convolvulaceae, Euphorbiaceae, Malvaceae and Sterculiaceae, in decreasing order. The number of weed species per plot ranged from 6 to 18, but there was no difference between the mean percentages of different weeds under the canopies of the progenies. The lowest weed fresh and dry matter masses occurred in progenies JG1 and SM8, respectively. There were no differences between progenies with regard to root collar diameter and leaf area; however, one of the lowest weed dry matter yields was observed under the canopy of progeny FE4, which showed the largest canopy diameter.

scholarly journals Correlations and path analysis of morphological and yield traits of cactus pear accessions

2013 ◽  
Vol 13 (3) ◽  
pp. 203-207 ◽  
Author(s):  
Diogo Gonçalves Neder ◽  
Fabiane Rabelo da Costa ◽  
Ricardo Loiola Edvan ◽  
Lenildo Teixeira Souto Filho
Keyword(s):  
Path Analysis ◽  
Dry Matter ◽  
Selection Process ◽  
Morphological Characteristics ◽  
Indirect Selection ◽  
Strongly Correlated ◽  
Fresh Matter ◽  
Cactus Pear ◽  
Green Matter ◽  
Selection For

The objectives of this study were to evaluate the relationships between morphological characteristics and fresh matter yield of cactus pear and identify their direct and indirect effects. Nineteen accessions were evaluated for the following traits: number (NCl), thickness (ThCl), length (LCl) and width (WCl) of cladodes, plant height (PH) and plant width (PW), and green matter yield (GMY), dry matter yield (DMY) and dry matter percentage (DM). The correlations were estimated, and path analysis was performed by the method proposed by Wright. GMY was strongly correlated with DMY, allowing indirect selection for this trait. NCl and ThCl had a direct effect on GMY and can be used for indirect selection or as secondary traits in the selection process. Given the lack of significant correlations between MS and DMY, it is possible to select a palm variety with high DMY and DM.

scholarly journals NONLINEAR AGROMETEOROLOGICAL MODELS FOR ESTIMATING LYCHEE FRUIT GROWTH

2017 ◽  
Vol 39 (2) ◽  
Author(s):  
LUCAS EDUARDO DE OLIVEIRA APARECIDO ◽  
RAFAEL BIBIANO FERREIRA ◽  
GLAUCO DE SOUZA ROLIM ◽  
BIANCA SARZI DE SOUZA ◽  
PAULO SERGIO DE SOUZA
Keyword(s):  
Fruit Development ◽  
Dry Matter ◽  
Potential Evapotranspiration ◽  
Climatic Conditions ◽  
Fruit Growth ◽  
Multivariate Models ◽  
Degree Days ◽  
Fresh Matter ◽  
Meteorological Elements ◽  
Fruit Diameter

ABSTRACT The influence of climate on the development of lychee fruit is complex, but few studies have discussed the problem. We developed agrometeorological models for simulating the development of fruit fresh matter (FM), fruit dry matter (DM), fruit length (LE), fruit diameter (DI), fruit volume (VO), and fruit number per cluster (FN) of the “Bengal” lychee cultivar as functions of climatic conditions. We conducted three analyses: (a) the influence of mean meteorological elements on the rates of fruit growth, (b) estimation of fruit development by the agrometeorological models using sigmoidal adjustments, and (c) simulation of fruit development using multiple nonlinear regression of two meteorological elements to improve the accuracy. A rate of water deficit (WD) near 5 mm d-1 maximised FM, DM, LE, DI, and VO. Increases in potential evapotranspiration (PET), degree days (DD), and actual evapotranspiration (AET) were correlated with increases in VO and decreases in LE and NF. Models estimating fruit development indicated that the accumulation of WD, PET, AET, and DD had sigmoidal relationships with all variables of fruit growth except FN. FN decreased as WD, PET, AET, and DD increased. The adjusted multivariate models were accurate, with the largest error of 6.45 cm3 (VO). The best models were: FM = f(SWD, DD), LE = f(SAET, DD), DI = f(SWD, DD), VO = f(SWD, DD), and FN = f(SAET, WD).

scholarly journals Pruning of the main stem of Marigold: effect on capitula yield

2017 ◽  
Vol 35 (3) ◽  
pp. 425-427
Author(s):  
Jana Koefender ◽  
André Schoffel ◽  
Diego P Golle ◽  
Candida E Manfio ◽  
Alice PB Dambróz ◽  
...  
Keyword(s):  
Dry Matter ◽  
Block Design ◽  
Factorial Experiment ◽  
Main Stem ◽  
Flower Bud ◽  
Fresh Matter ◽  
Randomized Complete Block Design

ABSTRACT The purpose of this work was to evaluate the influence of cutting the apex of the main stem of marigold plants on floral capitula yield. The experiment was carried out in a randomized complete block design, with five replicates. The following removal stages of the main stem apexes were studied: control (without pruning), up to 10 leaves, up to 15 leaves and visible flower bud. Three harvest periods were also evaluated: July, August and September, composing a factorial experiment in a 4x3 arrangement. The diameter, number, fresh matter and the dry capitula were evaluated. The most significant effect of cutting the apex of the main stem on fresh and dry matter of the capitula was obtained when the technique was performed at the time the plants had up to 15 leaves and visible flower bud. The harvesting performed in September showed to be the most promising, since it presented the larger diameter, higher number and higher fresh matter and the dry capitula.

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