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Gas exchanges and water-use efficiency of Nopalea cochenillifera intercropped under edaphic practices
Get PDFThe Nopalea forage cactus (Nopalea cochenillifera) is the main xerophilic species cultivated in Brazil, highlighted as a compatible biological element with the semiarid environment. However, studies on its physiological aspects are still scarce. In this context, an experiment was performed in the Pendência Experimental Station, belonging to the State Company of Agricultural Research of Paraíba (EMEPA-PB), municipality of Soledade, state of Paraíba, Brazil, aiming to evaluate the gas exchanges and the water-use efficiency of intercropped Nopalea Cochenillifera plants in the soil under different edaphic managements. The treatments were distributed in randomized blocks, with three replications in a 2 × 5 factorial scheme, corresponding to the soil without and with mulch and five types of cultivation of Nopalea forage cactus, in monoculture and intercropped with forage watermelon, millet, sorghum, and buffelgrass. The analyzed variables were: stomatal conductance, transpiration rate, net photosynthesis rate, and internal CO2 concentration, besides the instantaneous water-use efficiency, intrinsic water-use efficiency, and instantaneous carboxylation efficiency. The use of soil mulch satisfactorily increased the photosynthetic rate of the forage cactus; this type of practice can aid in the productive development of the crop in semiarid zones, whereas the intercropping with buffelgrass and forage watermelon stimulated photosynthesis and the water-use efficiency.The Nopalea forage cactus (Nopalea cochenillifera) is the main xerophilic species cultivated in Brazil, highlighted as a compatible biological element with the semiarid environment. However, studies on its physiological aspects are still scarce. In this context, an experiment was performed in the Pendência Experimental Station, belonging to the State Company of Agricultural Research of Paraíba (EMEPA-PB), municipality of Soledade, state of Paraíba, Brazil, aiming to evaluate the gas exchanges and the water-use efficiency of intercropped Nopalea Cochenillifera plants in the soil under different edaphic managements. The treatments were distributed in randomized blocks, with three replications in a 2 × 5 factorial scheme, corresponding to the soil without and with mulch and five types of cultivation of Nopalea forage cactus, in monoculture and intercropped with forage watermelon, millet, sorghum, and buffelgrass. The analyzed variables were: stomatal conductance, transpiration rate, net photosynthesis rate, and internal CO2 concentration, besides the instantaneous water-use efficiency, intrinsic water-use efficiency, and instantaneous carboxylation efficiency. The use of soil mulch satisfactorily increased the photosynthetic rate of the forage cactus; this type of practice can aid in the productive development of the crop in semiarid zones, whereas the intercropping with buffelgrass and forage watermelon stimulated photosynthesis and the water-use efficiency
Do planting methods and nitrogen management interfere with the economic viability of the melon crop?
Get PDFProper crop management results in higher profitability and the verification of economic viability is paramount to the definition of the methodologies used. This study aimed to verify the economic viability of seedlings or seeds use, associated with the inoculation with Azospirillum brasilense and nitrogen in topdressing fertilization in Cantaloupe melon production. The experiment was designed in randomized blocks with eight treatments. The treatments were composed of planting methods (seedling or seed), inoculation with Azospirillum brasilense (with or without), and partial application of 120 kg ha-1 of nitrogen as topdressing fertilization (with and without). It was verified that operations and seed acquisition represent the major cost factors. As for treatments, the use of seedling transplants with topdressing fertilization with nitrogen results in an increase of up to 37.01% in fruit production and, consequently, increases the indicators of economic viability. Also, A. brasilense, although not resulting in significantly higher production, raises the profitability. In this way, the seedling transplant, combined with the nitrogen in topdressing fertilization, results in higher profitability, and the use of A. brasilense is a technique with the potential for use in melon cultivation.Proper crop management results in higher profitability and the verification of economic viability is paramount to the definition of the methodologies used. This study aimed to verify the economic viability of seedlings or seeds use, associated with the inoculation with Azospirillum brasilense and nitrogen in topdressing fertilization in Cantaloupe melon production. The experiment was designed in randomized blocks with eight treatments. The treatments were composed of planting methods (seedling or seed), inoculation with Azospirillum brasilense (with or without), and partial application of 120 kg ha-1 of nitrogen as topdressing fertilization (with and without). It was verified that operations and seed acquisition represent the major cost factors. As for treatments, the use of seedling transplants with topdressing fertilization with nitrogen results in an increase of up to 37.01% in fruit production and, consequently, increases the indicators of economic viability. Also, A. brasilense, although not resulting in significantly higher production, raises the profitability. In this way, the seedling transplant, combined with the nitrogen in topdressing fertilization, results in higher profitability, and the use of A. brasilense is a technique with the potential for use in melon cultivation
Arbuscular mycorrhizal fungi as mitigating agents of salt stress in Formosa papaya seedlings
Get PDFThe objective of the present study was to evaluate the effect of mycorrhization on the nutritional, hydric and biochemical components of papaya seedlings, Carica papaia L., from the Formosa Group, Hybrid Tainung Nº 1, submitted to irrigation with saline water. The research was conducted at the Federal Institute of Paraíba, Sousa Campus, from March to December 2018. The experimental design used completely randomized blocks, with treatments arranged in a 4 x 5 factorial scheme, referring to the fungi species: Gigaspora candida, Acaulospora scrobiculata, Dentiscutata heterogama and without mycorrhizae, and the five salt concentrations in irrigation water: 0.0; 10.0; 20.0; 30.0 and 40.0 mmolc L-1 in four repetitions. The characteristics evaluated were: relative water content, water saturation deficit, membrane damage, photosynthetic pigments, concentration and accumulation of nitrogen, phosphorus, potassium, sodium and the relationship between potassium and sodium concentrations in leaf tissue. The species D. heterogama and G. candida presented the highest rates of leaf hydration and the lowest damage to biomembranes at all saline levels. Mycorrhizae increased the absorption of N and P, especially from 30 mmolc L-1 of salt. A greater relationship between potassium and sodium concentrations was evidenced in seedlings mycorrhized with D. heterogama.The objective of the present study was to evaluate the effect of mycorrhization on the nutritional, hydric and biochemical components of papaya seedlings, Carica papaia L., from the Formosa Group, Hybrid Tainung Nº 1, submitted to irrigation with saline water. The research was conducted at the Federal Institute of Paraíba, Sousa Campus, from March to December 2018. The experimental design used completely randomized blocks, with treatments arranged in a 4 x 5 factorial scheme, referring to the fungi species: Gigaspora candida, Acaulospora scrobiculata, Dentiscutata heterogama and without mycorrhizae, and the five salt concentrations in irrigation water: 0.0; 10.0; 20.0; 30.0 and 40.0 mmolc L-1 in four repetitions. The characteristics evaluated were: relative water content, water saturation deficit, membrane damage, photosynthetic pigments, concentration and accumulation of nitrogen, phosphorus, potassium, sodium and the relationship between potassium and sodium concentrations in leaf tissue. The species D. heterogama and G. candida presented the highest rates of leaf hydration and the lowest damage to biomembranes at all saline levels. Mycorrhizae increased the absorption of N and P, especially from 30 mmolc L-1 of salt. A greater relationship between potassium and sodium concentrations was evidenced in seedlings mycorrhized with D. heterogama
Application strategies of saline water and nitrogen doses in mini watermelon cultivation
Get PDFSalt stress is highlighted as one of the limiting factors for the establishment of agriculture in the semiarid region of Northeastern Brazil. In this context, it is essential to look for new strategies aiming at minimizing the effects of salt stress on the crops. The present work aimed to evaluate the photochemical efficiency, photosynthetic pigments, and growth of the watermelon cv. Sugar Baby under different use strategies with saline waters and nitrogen fertilization. The experiment was conducted in a protected environment at the Center of Technology and Natural Resources of the Federal University of Campina Grande, municipality of Campina Grande, Paraíba. An experimental design in randomized blocks was adopted, arranged in a 6 x 2 factorial scheme, with six management strategies of water salinity and two nitrogen doses (corresponding to 50 and 100% of the recommendation), with five replications. Two salinity levels of the irrigation water were studied, one with low and another with a high level of electrical conductivity of the water (ECw = 0.8 and 3.2 dS m-1). The watermelon cv. Sugar Baby expressed higher sensitivity to salt stress in the flowering phase, with a decrease in the synthesis of chlorophyll b, chlorophyll total, and carotenoids. The 50% dose of N provided an increment in the initial fluorescence, stem diameter, and the number of leaves of the watermelon cv. Sugar Baby. The length of the main branch of the watermelon plants decreased with the salt stress applied in the fructification phase; however, the fertilization with 100% of N stimulated a higher growth when the irrigation with saline waters was performed at the vegetative and flowering phases.Salt stress is highlighted as one of the limiting factors for the establishment of agriculture in the semiarid region of Northeastern Brazil. In this context, it is essential to look for new strategies aiming at minimizing the effects of salt stress on the crops. The present work aimed to evaluate the photochemical efficiency, photosynthetic pigments, and growth of the watermelon cv. Sugar Baby under different use strategies with saline waters and nitrogen fertilization. The experiment was conducted in a protected environment at the Center of Technology and Natural Resources of the Federal University of Campina Grande, municipality of Campina Grande, Paraíba. An experimental design in randomized blocks was adopted, arranged in a 6 x 2 factorial scheme, with six management strategies of water salinity and two nitrogen doses (corresponding to 50 and 100% of the recommendation), with five replications. Two salinity levels of the irrigation water were studied, one with low and another with a high level of electrical conductivity of the water (ECw = 0.8 and 3.2 dS m-1). The watermelon cv. Sugar Baby expressed higher sensitivity to salt stress in the flowering phase, with a decrease in the synthesis of chlorophyll b, chlorophyll total, and carotenoids. The 50% dose of N provided an increment in the initial fluorescence, stem diameter, and the number of leaves of the watermelon cv. Sugar Baby. The length of the main branch of the watermelon plants decreased with the salt stress applied in the fructification phase; however, the fertilization with 100% of N stimulated a higher growth when the irrigation with saline waters was performed at the vegetative and flowering phases
Management of soil cover and its influence on phytosociology, physiology and fig production
Get PDFThe fig stands out as an important source of food for the human diet, especially minerals and fibers. Weeds are a major concern in the conduct of fig orchards. Therefore, the objective of this study was to evaluate the effect of management of vegetable cover of soil (CVS) on weed phytosociology, physiological characteristics and fig production. The experimental design was a randomized complete block design with four replications. The treatments consisted of six CVS managements: cover maintenance, weeding, lodging, mowing, application of herbicides diquat and glyphosate. For the constitution of the vegetal cover a consortium of three winter forage species, vetch and black oats sowed and the ryegrass remaining in the area of previous years were used. Thus, we evaluated the phytosociology of weeds present in the area, at two different times, assigning parameters related to frequency, density and abundance, which establish the species importance value index (IVI), besides the dry mass of the aerial part of the weeds. Physiological parameters and total fruit yield were evaluated at the end of the crop cycle. The different CVS management methods influenced the weed community, mainly in the diversity, density and dry mass of the aerial part. There is no interference in the physiological variables of the fig plants and in the total production of fig fruits. We highlight the maintenance of coverage and lodging as the most promising for the management of weeds found fig orchards.The fig stands out as an important source of food for the human diet, especially minerals and fibers. Weeds are a major concern in the conduct of fig orchards. Therefore, the objective of this study was to evaluate the effect of management of vegetable cover of soil (CVS) on weed phytosociology, physiological characteristics and fig production. The experimental design was a randomized complete block design with four replications. The treatments consisted of six CVS managements: cover maintenance, weeding, lodging, mowing, application of herbicides diquat and glyphosate. For the constitution of the vegetal cover a consortium of three winter forage species, vetch and black oats sowed and the ryegrass remaining in the area of previous years were used. Thus, we evaluated the phytosociology of weeds present in the area, at two different times, assigning parameters related to frequency, density and abundance, which establish the species importance value index (IVI), besides the dry mass of the aerial part of the weeds. Physiological parameters and total fruit yield were evaluated at the end of the crop cycle. The different CVS management methods influenced the weed community, mainly in the diversity, density and dry mass of the aerial part. There is no interference in the physiological variables of the fig plants and in the total production of fig fruits. We highlight the maintenance of coverage and lodging as the most promising for the management of weeds found fig orchards
Fruit yield and quality of Palmer mango trees under different irrigation systems
Get PDFMango production has been having a great economical expression in the Brazilian agriculture. However, the economic crisis and increased competitiveness of the international market required improvements in the crop efficiency for its sustainability. In this context, the objective of this work was to evaluate the effect of different irrigation system on the physiology and fruit yield and quality of Palmer mango trees in the semiarid conditions of the Lower Middle São Francisco Valley, Brazil. The experiment was carried out at the Agranvil Farm, in Petrolina, state of Pernambuco, Brazil, with harvests in July 2013 and October 2014. A randomized block statistical design was used, with four treatments replicated in 5 blocks, during two production cycles. The treatments consisted of four irrigation systems: one micro sprinkler under the plant canopy (MSPC); drip system with two lateral lines per plant row (DSLL); one micro sprinkler between plants (MSBP); and ring-shaped drip system around the plants (RSDS). All treatments provided a flow rate of 56 L h-1 plant-1. The physiological characteristics evaluated were: photosynthesis, stomatal conductance, leaf transpiration, and leaf temperature. Fruit yield, quantity, mean weight, volume, soluble solid content, titratable acidity (TA), density, and pulp firmness were evaluated after the harvest. The evaluated treatments presented significant differences for the physiological variables. The treatment DSLL provided higher number of fruits and fruit yield, and the treatment MSBP provided the lowest results for these variables.Mango production has been having a great economical expression in the Brazilian agriculture. However, the economic crisis and increased competitiveness of the international market required improvements in the crop efficiency for its sustainability. In this context, the objective of this work was to evaluate the effect of different irrigation system on the physiology and fruit yield and quality of Palmer mango trees in the semiarid conditions of the Lower Middle São Francisco Valley, Brazil. The experiment was carried out at the Agranvil Farm, in Petrolina, state of Pernambuco, Brazil, with harvests in July 2013 and October 2014. A randomized block statistical design was used, with four treatments replicated in 5 blocks, during two production cycles. The treatments consisted of four irrigation systems: one micro sprinkler under the plant canopy (MSPC); drip system with two lateral lines per plant row (DSLL); one micro sprinkler between plants (MSBP); and ring-shaped drip system around the plants (RSDS). All treatments provided a flow rate of 56 L h-1 plant-1. The physiological characteristics evaluated were: photosynthesis, stomatal conductance, leaf transpiration, and leaf temperature. Fruit yield, quantity, mean weight, volume, soluble solid content, titratable acidity (TA), density, and pulp firmness were evaluated after the harvest. The evaluated treatments presented significant differences for the physiological variables. The treatment DSLL provided higher number of fruits and fruit yield, and the treatment MSBP provided the lowest results for these variables
Ornamental potential of species from the ferruginous Campo rupestre of the Carajás National Forest, Brazilian Amazon
Get PDFThe flora of the ferruginous Campo rupestre that occur over the immense iron deposits of the Carajás National Forest is very unique, with several endemic and rare species. This vegetation is directly affected by mining activity, as a result of vegetation suppression and the profound disfigurement of habitats. The objective of this work was to identify the ornamental potential of the flora of the ferruginous Campo rupestre, as a strategy for ex situ conservation of ecosystem species. The species present in ten plots of 5 x 5 m were surveyed in different areas of the ferruginous Campo rupestre on the N1 plateau and the ornamental potential of each species was evaluated following a characterization key, considering morphology and habitat of occurrence. Subsequently, the species were compared with those already present on the market, as ornamental, based on the literature and on sites specialized in the sale of ornamental plants in Brazil. A total of 33 species with ornamental potential were found, distributed in 32 genera and 19 families. Most species showed high functionality for ornamentation and similarity with nationally consolidated ornamentals. Catasetum planiceps, Cyrtopodium andersonii, Epidendrum nocturnum, Mandevilla scabra, Norantea guianensis and Sobralia liliastrum have a consolidated ornamental market. The data collected support ex situ conservation strategies of the flora of the ferruginous Campo rupestre, such as its valorization, local commercialization and income generation for small extractivists in the region.The flora of the ferruginous Campo rupestre that occur over the immense iron deposits of the Carajás National Forest is very unique, with several endemic and rare species. This vegetation is directly affected by mining activity, as a result of vegetation suppression and the profound disfigurement of habitats. The objective of this work was to identify the ornamental potential of the flora of the ferruginous Campo rupestre, as a strategy for ex situ conservation of ecosystem species. The species present in ten plots of 5 x 5 m were surveyed in different areas of the ferruginous Campo rupestre on the N1 plateau and the ornamental potential of each species was evaluated following a characterization key, considering morphology and habitat of occurrence. Subsequently, the species were compared with those already present on the market, as ornamental, based on the literature and on sites specialized in the sale of ornamental plants in Brazil. A total of 33 species with ornamental potential were found, distributed in 32 genera and 19 families. Most species showed high functionality for ornamentation and similarity with nationally consolidated ornamentals. Catasetum planiceps, Cyrtopodium andersonii, Epidendrum nocturnum, Mandevilla scabra, Norantea guianensis and Sobralia liliastrum have a consolidated ornamental market. The data collected support ex situ conservation strategies of the flora of the ferruginous Campo rupestre, such as its valorization, local commercialization and income generation for small extractivists in the region
Genetic dissimilarity between biofortified lettuce genotypes for leaf carotenoid levels
Get PDFLettuce is the main leafy vegetable, presenting the highest consumption and economic importance in the world. In the recent decades, concerns about vitamin A deficiency have led Brazilian researchers to develop cultivars with higher levels of carotenoids provitamin A. Therefore the experiment aimed to verify the genetic dissimilarity of biofortified lettuce genotypes, investigating the correlation between agronomic characteristics and the potential for use to increase the carotenoid content in future breeding programs. Ninety one genotypes were evaluated, with 86 lettuce strains from hybridization between cultivars Pira 72 versus Uberlândia 10000 (rich in carotenoids) followed by three successive self-fertilizations and 5 commercial cultivars (Grand Rapids; UFU MC BIOFORT1; Pira 72; Uberlândia 10000 and Robusta).During the course of the trial, were evaluated characteristics as chlorophyll content of the leaves, plant diameter, stem diameter and the number of leaves per plant were counted. Genetic diversity was represented by a dendrogram that was obtained using the hierarchical method of UPGMA and the optimization method of Tocher. There is genetic divergence between the lettuce genotypes analyzed, and the carotenoid content character contributed most significantly to the divergence between the evaluated genotypes. The UFU215#12 genotypes; UFU215#14; UFU215#2; UFU 215#1; UFU215#4; UFU199#3 and UFU199#2 have good agronomic characteristics and high levels of carotenoids, being promising to continue the biofortified lettuce breeding program, aiming to obtain new cultivars rich in carotenoids pro vitamin A.Lettuce is the main leafy vegetable, presenting the highest consumption and economic importance in the world. In the recent decades, concerns about vitamin A deficiency have led Brazilian researchers to develop cultivars with higher levels of carotenoids provitamin A. Therefore the experiment aimed to verify the genetic dissimilarity of biofortified lettuce genotypes, investigating the correlation between agronomic characteristics and the potential for use to increase the carotenoid content in future breeding programs. Ninety one genotypes were evaluated, with 86 lettuce strains from hybridization between cultivars Pira 72 versus Uberlândia 10000 (rich in carotenoids) followed by three successive self-fertilizations and 5 commercial cultivars (Grand Rapids; UFU MC BIOFORT1; Pira 72; Uberlândia 10000 and Robusta).During the course of the trial, were evaluated characteristics as chlorophyll content of the leaves, plant diameter, stem diameter and the number of leaves per plant were counted. Genetic diversity was represented by a dendrogram that was obtained using the hierarchical method of UPGMA and the optimization method of Tocher. There is genetic divergence between the lettuce genotypes analyzed, and the carotenoid content character contributed most significantly to the divergence between the evaluated genotypes. The UFU215#12 genotypes; UFU215#14; UFU215#2; UFU 215#1; UFU215#4; UFU199#3 and UFU199#2 have good agronomic characteristics and high levels of carotenoids, being promising to continue the biofortified lettuce breeding program, aiming to obtain new cultivars rich in carotenoids pro vitamin A
Chemical and mineral characteristics, bioactive compounds and antioxidant activity of blackberries grown in an organic system
Get PDFBlackberry bushes have increasingly drawn producers’ and consumers’ interest since they find their cultivation characteristics, production and nutraceutical qualities advantageous. Both chemical and mineral characteristics, bioactive compounds and antioxidant activity found in blackberries are extremely relevant factors to be considered when cultivars are chosen. Chemical analyses of the nutritional composition of fruit is important, since they can help studies of quality genotypes. Besides, fruit with high nutritional values contribute to human health when they are often consumed. This study aimed at evaluating chemical and mineral characteristics, besides bioactive compounds and antioxidant activity, of different blackberry bush genotypes grown in an organic farming system in Pelotas, Rio Grande do Sul (RS), Brazil. Production, soluble solid content, hydrogenionic potential, total titratable acidity, SS/TA ratio, minerals, phenolic compounds, anthocyanins and antioxidant activity of six blackberry bush genotypes – ‘Tupy’, ‘BRS Xingu’, Selection Black 178, Selection Black 128, Selection Black 112 and Selection Black 145 – were evaluated. It was a randomized block design with three replicates of every plant. Selection Black 178 yielded fruits with the highest value of SS/TA ratio and had the highest accumulated production. The highest anthocyanin content was found in ‘BRS Xingu’. Selection Black 112 had the highest total contents of phenolic compounds and the highest antioxidant activity, whereas ‘Tupy’ exhibited their lowest values. Selection Black 178 adapted well to the organic farming system, a fact that did not happen to Selection Black 128.Blackberry bushes have increasingly drawn producers’ and consumers’ interest since they find their cultivation characteristics, production and nutraceutical qualities advantageous. Both chemical and mineral characteristics, bioactive compounds and antioxidant activity found in blackberries are extremely relevant factors to be considered when cultivars are chosen. Chemical analyses of the nutritional composition of fruit is important, since they can help studies of quality genotypes. Besides, fruit with high nutritional values contribute to human health when they are often consumed. This study aimed at evaluating chemical and mineral characteristics, besides bioactive compounds and antioxidant activity, of different blackberry bush genotypes grown in an organic farming system in Pelotas, Rio Grande do Sul (RS), Brazil. Production, soluble solid content, hydrogenionic potential, total titratable acidity, SS/TA ratio, minerals, phenolic compounds, anthocyanins and antioxidant activity of six blackberry bush genotypes – ‘Tupy’, ‘BRS Xingu’, Selection Black 178, Selection Black 128, Selection Black 112 and Selection Black 145 – were evaluated. It was a randomized block design with three replicates of every plant. Selection Black 178 yielded fruits with the highest value of SS/TA ratio and had the highest accumulated production. The highest anthocyanin content was found in ‘BRS Xingu’. Selection Black 112 had the highest total contents of phenolic compounds and the highest antioxidant activity, whereas ‘Tupy’ exhibited their lowest values. Selection Black 178 adapted well to the organic farming system, a fact that did not happen to Selection Black 128
Phenology and productive performance of chamomile in sowing dates and spacing between plants
Get PDFThe present work has aimed to evaluate phenology and productive performance of chamomile in a subtropical weather region, sown in different dates and spacings in between plants. The experiment took place in Santa Maria – RS with four sowing dates in the year 2017 (18/03, 28/04, 30/06 and 31/08) and seven spacings along plants in rows (5, 10, 15, 20, 25, 30 and 40 cm), spaced 30 cm between each other. Phenological observations were made every two or three days in two plants per portion while also accounting for the number of nodes in the main stem. The harvest of chamomile floral chapters was performed manually from the beggining of flowering and repeated biweekly until plant maturation. Productivity of dry floral chapters as well as content and productivity of essential oils were evaluated. It was established that sowing dates affect the productivity of dry floral chapters, content and productivity of essential oil from cv. Mandirituba chamomile, with the sowings of March 18th and April 28th presenting the highest values for such variables. Increasing the space between plants from the 10 cm line to 40 cm in lines spaced in 30 cm has shown a linear tendency of decreasing the productivity of dry floral chapters. Spacings between plants did not affect the phenological development of chamomile, however, sowing dates interfered in the thermal time of six evaluated subperiods regarding plastochron and the final number of nodes.The present work has aimed to evaluate phenology and productive performance of chamomile in a subtropical weather region, sown in different dates and spacings in between plants. The experiment took place in Santa Maria – RS with four sowing dates in the year 2017 (18/03, 28/04, 30/06 and 31/08) and seven spacings along plants in rows (5, 10, 15, 20, 25, 30 and 40 cm), spaced 30 cm between each other. Phenological observations were made every two or three days in two plants per portion while also accounting for the number of nodes in the main stem. The harvest of chamomile floral chapters was performed manually from the beggining of flowering and repeated biweekly until plant maturation. Productivity of dry floral chapters as well as content and productivity of essential oils were evaluated. It was established that sowing dates affect the productivity of dry floral chapters, content and productivity of essential oil from cv. Mandirituba chamomile, with the sowings of March 18th and April 28th presenting the highest values for such variables. Increasing the space between plants from the 10 cm line to 40 cm in lines spaced in 30 cm has shown a linear tendency of decreasing the productivity of dry floral chapters. Spacings between plants did not affect the phenological development of chamomile, however, sowing dates interfered in the thermal time of six evaluated subperiods regarding plastochron and the final number of nodes