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Efficiency of application of Trichoderma on the physiological quality and health of cowpea seeds
Get PDFOne of the main causes of low productivity of cowpea crops in Brazil is the use of low quality seeds. Low quality seeds have a high degree of infestation by phytopathogens, mainly fungi. Seed treatment with biological control agents, such as fungi of the genus Trichoderma, is a useful alternative to reduce or inhibit the transmission of diseases via seeds. In view of the above, this study aims to evaluate the physiological and sanitary quality of cowpea seeds treated with conidia of Trichoderma sp. (1.2, 2.4, 4.8 and 9.6 x 108 CFU g-1). We evaluated the germination and the sanity of seeds, length of seedling radicles, and production of indole acetic acid (IAA) by fungi. The experimental design was completely randomized in all experiments. In general, there was a predominance of Fusarium spp. and Rhizoctonia solani. The treatment of seeds with the conidia of Trichoderma sp. was positive for the parameters related to germination and radicle length of cowpea beans up to the concentration 4.8 x 108 CFU g-1. We conclude that the application of Trichoderma sp. was efficient in reducing the incidence of Fusarium spp., and promoted the germination and elongation of the radicle in cowpea.One of the main causes of low productivity of cowpea crops in Brazil is the use of low quality seeds. Low quality seeds have a high degree of infestation by phytopathogens, mainly fungi. Seed treatment with biological control agents, such as fungi of the genus Trichoderma, is a useful alternative to reduce or inhibit the transmission of diseases via seeds. In view of the above, this study aims to evaluate the physiological and sanitary quality of cowpea seeds treated with conidia of Trichoderma sp. (1.2, 2.4, 4.8 and 9.6 x 108 CFU g-1). We evaluated the germination and the sanity of seeds, length of seedling radicles, and production of indole acetic acid (IAA) by fungi. The experimental design was completely randomized in all experiments. In general, there was a predominance of Fusarium spp. and Rhizoctonia solani. The treatment of seeds with the conidia of Trichoderma sp. was positive for the parameters related to germination and radicle length of cowpea beans up to the concentration 4.8 x 108 CFU g-1. We conclude that the application of Trichoderma sp. was efficient in reducing the incidence of Fusarium spp., and promoted the germination and elongation of the radicle in cowpea
Growth and flowering of colored cotton cultivated in soils of distincts ESP and sheep manure
Get PDFThe inadequate management of irrigation has promoted the increase in the area of degraded soils through salinization and/or sodification, especially in irrigated perimeters of the northeastern semiarid, promoting environmental impacts and decrease in crop yield. In this manner, studies that aim to evaluate the tolerance of crops to salts, and/or techniques that minimize the deleterious effects of salt stress are highly viable. Based on this, the present study aimed to evaluate the influence of sheep manure doses over growth and flowering of the colored cotton cv. BRS Topázio, cultivated in soils with different exchangeable sodium percentages. A randomized block design was adopted, in a 5 x 4 factorial scheme, corresponding to the treatments of five exchangeable sodium percentages – ESP: 8.84, 12.55, 18.80, 28.80 and 38.80% and four sheep manure doses: 0, 5, 10 and 15% based on the volume of the soil, with 3 replications. At 90 days after sowing, it could be verified that the increment in the sheep manure doses added to the soil mitigated the negative effect of the ESP over the production of flower buds, beside stimulating plant growth, flower production and reducing the rate of flower abortion, independently of the ESP. The cotton cv. BRS Topázio is tolerant to soil ESP up to 38.8%, and anthesis is anticipated by the increase in exchangeable sodium.The inadequate management of irrigation has promoted the increase in the area of degraded soils through salinization and/or sodification, especially in irrigated perimeters of the northeastern semiarid, promoting environmental impacts and decrease in crop yield. In this manner, studies that aim to evaluate the tolerance of crops to salts, and/or techniques that minimize the deleterious effects of salt stress are highly viable. Based on this, the present study aimed to evaluate the influence of sheep manure doses over growth and flowering of the colored cotton cv. BRS Topázio, cultivated in soils with different exchangeable sodium percentages. A randomized block design was adopted, in a 5 x 4 factorial scheme, corresponding to the treatments of five exchangeable sodium percentages – ESP: 8.84, 12.55, 18.80, 28.80 and 38.80% and four sheep manure doses: 0, 5, 10 and 15% based on the volume of the soil, with 3 replications. At 90 days after sowing, it could be verified that the increment in the sheep manure doses added to the soil mitigated the negative effect of the ESP over the production of flower buds, beside stimulating plant growth, flower production and reducing the rate of flower abortion, independently of the ESP. The cotton cv. BRS Topázio is tolerant to soil ESP up to 38.8%, and anthesis is anticipated by the increase in exchangeable sodium
Chemical characteristics of soil cultivated with vine and submitted to nitrogen and organic fertilization at the semiarid of the Rio Grande do Norte State, Brazil
Get PDFA probable reason for the scarce levels of N in the soils of the semi-arid regions would be the low levels of organic matter in these soils. In this way, the aim of the present study was to evaluate the effects of nitrogen and organic fertilization and their interaction on chemical properties of soils cultivated with ‘Isabel Precoce’ vines in the semiarid oh the Rio Grande do Norte State, Brazil. The experiment was carried out at the Experimental Farm of the Federal Rural University of the Semi-arid Region, in Mossoró, RN. The soil in the area is classified as a Distrofic Red Argisol with sandy texture. The research was carried out in two cycles of grape production. The experiment was accomplish in a randomized blocks design, with six repetitions, in a 5 x 2 factorial scheme, corresponding to 5 doses of nitrogen fertilization (0, 30, 60, 90 and 120 kg ha-1), in the absence and presence of organic fertilization 0 and 20 m3 ha-1, bovine manure). Samples of the 0-20 cm layer were collected for the evaluation of macro and micronutrient contents, pH, electric condutivity, organic matter and sum of bases. The N and organic fertilization doses influenced the chemical atributes evaluated. The interaction between nitrogen and organic fertilizer resulted in an increase in nutrient, organic matter and sum of bases content. N doses were responsible for reducing pH levels, resulting in higher amounts of nutrients availability.A probable reason for the scarce levels of N in the soils of the semi-arid regions would be the low levels of organic matter in these soils. In this way, the aim of the present study was to evaluate the effects of nitrogen and organic fertilization and their interaction on chemical properties of soils cultivated with ‘Isabel Precoce’ vines in the semiarid oh the Rio Grande do Norte State, Brazil. The experiment was carried out at the Experimental Farm of the Federal Rural University of the Semi-arid Region, in Mossoró, RN. The soil in the area is classified as a Distrofic Red Argisol with sandy texture. The research was carried out in two cycles of grape production. The experiment was accomplish in a randomized blocks design, with six repetitions, in a 5 x 2 factorial scheme, corresponding to 5 doses of nitrogen fertilization (0, 30, 60, 90 and 120 kg ha-1), in the absence and presence of organic fertilization 0 and 20 m3 ha-1, bovine manure). Samples of the 0-20 cm layer were collected for the evaluation of macro and micronutrient contents, pH, electric condutivity, organic matter and sum of bases. The N and organic fertilization doses influenced the chemical atributes evaluated. The interaction between nitrogen and organic fertilizer resulted in an increase in nutrient, organic matter and sum of bases content. N doses were responsible for reducing pH levels, resulting in higher amounts of nutrients availability
Multilevel modelling of the draft force required by seeder-fertilizers
Get PDFThe high production costs in agriculture have guiding the adoption of farming systems and new management techniques as well as the sizing of agricultural machinery. In this regard, planning entails knowledge on the efficiency according to the energy requirements parameters, so the farmer shall consider the characteristics of the soil on which the implement operates. The performance assessment of sowing-fertilize machines shows the effect of some variables on the draft requirement, so the experimental conditions, which might lead to different outcomes of implement operation, must be regarded. Therefore, it is necessary obtain metanalytical estimates to integrate the results available in the literature. Grounded on systematic review, this study aimed to model the draft imposed by sowing-fertilizing machines considering fixed effects, mainly soil characteristics, and random effects associated to the selected experiments. It was found that the best models according to information criteria may not always meet the assumptions as normality of the distribution of residuals and homoscedasticity. The variables such as bulk density of soil, stubble conditions, depth of fertilizer placement, and speed could accurately explain the draft requirement with mean squared deviation of 2.93 whereas the referred evaluator for the ASABE standard was 63.51. Forthcoming works may analyze the repeatability of the models considering different seeders under diverse configurations and operation conditionsThe high production costs in agriculture have guiding the adoption of farming systems and new management techniques as well as the sizing of agricultural machinery. In this regard, planning entails knowledge on the efficiency according to the energy requirements parameters, so the farmer shall consider the characteristics of the soil on which the implement operates. The performance assessment of sowing-fertilize machines shows the effect of some variables on the draft requirement, so the experimental conditions, which might lead to different outcomes of implement operation, must be regarded. Therefore, it is necessary obtain metanalytical estimates to integrate the results available in the literature. Grounded on systematic review, this study aimed to model the draft imposed by sowing-fertilizing machines considering fixed effects, mainly soil characteristics, and random effects associated to the selected experiments. It was found that the best models according to information criteria may not always meet the assumptions as normality of the distribution of residuals and homoscedasticity. The variables such as bulk density of soil, stubble conditions, depth of fertilizer placement, and speed could accurately explain the draft requirement with mean squared deviation of 2.93 whereas the referred evaluator for the ASABE standard was 63.51. Forthcoming works may analyze the repeatability of the models considering different seeders under diverse configurations and operation condition
Seed priming with sodium nitroprusside attenuates the effects of water deficit on soybean seedlings
Get PDFConsidering that water deficit is one of the main environmental factors responsible for low soybean yield and that nitric oxide (NO) has been shown to be a fundamental part of plant defense signaling during stress, the aim of the present study was to evaluate the effect of seed priming with nitric oxide on the induction of water deficit tolerance during the initial development of soybean. Thus, seeds were treated with 0 (water only), 50, 100 or 250 μmol.L-1 sodium nitroprusside for 6 hours. Additionally, untreated seeds were used. After drying, the seeds were placed in containers filled with a commercial substrate mixture and vermiculite and irrigated to 100% and 50% field capacity. Biometric and biochemical evaluations (pigment and proline contents) were performed after 14 days. It was concluded that pretreatment of soybean seeds with 50 to 250 μmol.L-1 SNP attenuated the effects of water deficit on stem growth, leaf area, and shoot dry matter and induced carotenoid biosynthesis. The accumulation of proline in the leaves was pronounced in the treatments with 100 and 250 μmol.L-1 SNP, while 100 μmol.L-1 SNP induced proline accumulation in the roots.Considering that water deficit is one of the main environmental factors responsible for low soybean yield and that nitric oxide (NO) has been shown to be a fundamental part of plant defense signaling during stress, the aim of the present study was to evaluate the effect of seed priming with nitric oxide on the induction of water deficit tolerance during the initial development of soybean. Thus, seeds were treated with 0 (water only), 50, 100 or 250 μmol.L-1 sodium nitroprusside for 6 hours. Additionally, untreated seeds were used. After drying, the seeds were placed in containers filled with a commercial substrate mixture and vermiculite and irrigated to 100% and 50% field capacity. Biometric and biochemical evaluations (pigment and proline contents) were performed after 14 days. It was concluded that pretreatment of soybean seeds with 50 to 250 μmol.L-1 SNP attenuated the effects of water deficit on stem growth, leaf area, and shoot dry matter and induced carotenoid biosynthesis. The accumulation of proline in the leaves was pronounced in the treatments with 100 and 250 μmol.L-1 SNP, while 100 μmol.L-1 SNP induced proline accumulation in the roots
Response of essential-oil yield of aromatic and medicinal plants to different harvesting strategies
Get PDFThe demand for aromatic and medicinal plants (AMPs) is growing worldwide, and most of them are from the wild collection. Today there is a consensus that for industrial purposes the AMPs must be cultivated. Many studies have shown the importance of the collection strategy used to guarantee the plant regeneration, and soil protection against erosion process in mountainous areas in the Mediterranean region. In this work, during three-year monitoring period we compared in four AMPs two harvest strategies by cutting biomass in 25% (BHI25) and 50% (BHI50) of oregano (Origanum bastetanum L.), lavender (Lavandula lanata L.); sage (Salvia lavandulifolia V.); and santolina (Santolina rosmarinifolia L.) in order to assess their effect on essential-oil content, and to be consistent with both plant and soil conservation in Mediterranean steeply sloping areas. The experimental plots were located in Lanjarón (Granada, SE Spain), on a 20% slope. According to the findings the strategy BHI50 of fresh herb of oregano, lavender, sage, and santolina produced essential-oil yield of 13.2 ± 1.74, 17.3 ± 1.69, 9.7 ± 5.21, and 10.8 ± 2.00 L·ha-1, respectively. Since significant differences were found between BHI25 and BHI50 strategies for harvest and distillation of aromatic plants, we recommend a rational harvest, leaving the 50% of the plant biomass in the field to avoid the soil degradation. In addition, with this rational harvest strategy encourages the sustainable AMP cultivation without significant alterations for essential-oil yields, and at the same time guaranteeing the regrowth, and conservation of them in its habitat. Therefore, encouragement local decision-making measures regarding environmental compatibility, social acceptability and economic viability in land use and management will be crucial. Otherwise, the inappropriate harvest of aromatic shrubs in mountain areas compromises land conservation.The demand for aromatic and medicinal plants (AMPs) is growing worldwide, and most of them are from the wild collection. Today there is a consensus that for industrial purposes the AMPs must be cultivated. Many studies have shown the importance of the collection strategy used to guarantee the plant regeneration, and soil protection against erosion process in mountainous areas in the Mediterranean region. In this work, during three-year monitoring period we compared in four AMPs two harvest strategies by cutting biomass in 25% (BHI25) and 50% (BHI50) of oregano (Origanum bastetanum L.), lavender (Lavandula lanata L.); sage (Salvia lavandulifolia V.); and santolina (Santolina rosmarinifolia L.) in order to assess their effect on essential-oil content, and to be consistent with both plant and soil conservation in Mediterranean steeply sloping areas. The experimental plots were located in Lanjarón (Granada, SE Spain), on a 20% slope. According to the findings the strategy BHI50 of fresh herb of oregano, lavender, sage, and santolina produced essential-oil yield of 13.2 ± 1.74, 17.3 ± 1.69, 9.7 ± 5.21, and 10.8 ± 2.00 L·ha-1, respectively. Since significant differences were found between BHI25 and BHI50 strategies for harvest and distillation of aromatic plants, we recommend a rational harvest, leaving the 50% of the plant biomass in the field to avoid the soil degradation. In addition, with this rational harvest strategy encourages the sustainable AMP cultivation without significant alterations for essential-oil yields, and at the same time guaranteeing the regrowth, and conservation of them in its habitat. Therefore, encouragement local decision-making measures regarding environmental compatibility, social acceptability and economic viability in land use and management will be crucial. Otherwise, the inappropriate harvest of aromatic shrubs in mountain areas compromises land conservation
Propagation of yellow mombin by stem and root cuttings treated with indolebutyric acid
Get PDFYellow mombin is a fruit species of growing interest in the agro-industrial sector, mainly in the North and Northeast regions of Brazil, although its commercial exploitation is still limited due to the lack of information regarding its propagation, among other factors. In this perspective, this work aimed to study the effect of the application of indolebutyric acid (IBA) in the vegetative propagation of yellow mombin by stem and root cuttings. The experiments were conducted in a plant nursery, under a completely randomized experimental design consisting of six concentrations of IBA (0, 1000, 2000, 3000, 4000 and 5000 mg.kg-1 in industrial talc), four replications, and ten cuttings per plot. The stem cutting experiment also evaluated the effect of the types of cuttings (tanchan, basal, stratified basal, medial, and apical), with the material being collected from a yellow mombin tree in full vegetative growth. The root cuttings were collected from a matrix plant in the stage of vegetative rest and cut into 15 cm length segments. After 120 days, the following variables were evaluated: percentage of living, sprouted, rooted, and calloused cuttings, and dry mass of roots and sprouts. The cuttings of the tanchan type showed higher survival and sprouting percentages, regardless of the concentration of IBA applied, whereas the rooting rate was low. The application of IBA increased the rooting percentage of the root cuttings until the maximum concentration of 5000 mg.kg-1, reaching 77.5%, although it did not influence the other variables analyzed. The root cuttings of yellow mombin exhibit good regeneration capacity.Yellow mombin is a fruit species of growing interest in the agro-industrial sector, mainly in the North and Northeast regions of Brazil, although its commercial exploitation is still limited due to the lack of information regarding its propagation, among other factors. In this perspective, this work aimed to study the effect of the application of indolebutyric acid (IBA) in the vegetative propagation of yellow mombin by stem and root cuttings. The experiments were conducted in a plant nursery, under a completely randomized experimental design consisting of six concentrations of IBA (0, 1000, 2000, 3000, 4000 and 5000 mg.kg-1 in industrial talc), four replications, and ten cuttings per plot. The stem cutting experiment also evaluated the effect of the types of cuttings (tanchan, basal, stratified basal, medial, and apical), with the material being collected from a yellow mombin tree in full vegetative growth. The root cuttings were collected from a matrix plant in the stage of vegetative rest and cut into 15 cm length segments. After 120 days, the following variables were evaluated: percentage of living, sprouted, rooted, and calloused cuttings, and dry mass of roots and sprouts. The cuttings of the tanchan type showed higher survival and sprouting percentages, regardless of the concentration of IBA applied, whereas the rooting rate was low. The application of IBA increased the rooting percentage of the root cuttings until the maximum concentration of 5000 mg.kg-1, reaching 77.5%, although it did not influence the other variables analyzed. The root cuttings of yellow mombin exhibit good regeneration capacity
Recovery and germinative response of Amaranthus deflexus L. seeds under different levels of water stress and luminosities
Get PDFThe objective of this work was to evaluate, in two experiments, the effect of water stress and luminosity on the germinative behavior and vigor of Amaranthus deflexus L seeds. The seeds were sown in Petri dishes containing two sheets of filter paper moistened with distilled water, in the control treatment. Using this treatment-control configuration, as a standard of comparison, two assays were performed using subsamples from the same A. deflexus seed population. In the first experiment (experiment 1), solutions of polyethylene glycol 6000 (PEG 6000) were used, providing osmotic potentials of -0.3; -0.6; -0.9; -1.2 and -1.5 MPa; however, in the second trial (experiment 2) osmotic potentials of -0.1; -0.2; -0.3; -0.4 and -0.5 MPa were used. At the end of the test, the ungerminated seeds for each treatment were washed and germinated on a filter paper moistened with water. The germination and vigor of the seeds were evaluated through the first germination count, germination test, germination speed index and average germination time. The experimental design was completely randomized, in a 2 x 6 factorial scheme, totaling twelve treatments, with four replicates of 50 seeds each, in both trials. Water stress negatively affects the performance of A. deflexus seeds, reducing germination and vigor from -0.1 MPa. Seed germination was compromised by the absence of light, regardless of the applied stress levels. There was an increase in seed germination after application of the same at higher levels of water stress.The objective of this work was to evaluate, in two experiments, the effect of water stress and luminosity on the germinative behavior and vigor of Amaranthus deflexus L seeds. The seeds were sown in Petri dishes containing two sheets of filter paper moistened with distilled water, in the control treatment. Using this treatment-control configuration, as a standard of comparison, two assays were performed using subsamples from the same A. deflexus seed population. In the first experiment (experiment 1), solutions of polyethylene glycol 6000 (PEG 6000) were used, providing osmotic potentials of -0.3; -0.6; -0.9; -1.2 and -1.5 MPa; however, in the second trial (experiment 2) osmotic potentials of -0.1; -0.2; -0.3; -0.4 and -0.5 MPa were used. At the end of the test, the ungerminated seeds for each treatment were washed and germinated on a filter paper moistened with water. The germination and vigor of the seeds were evaluated through the first germination count, germination test, germination speed index and average germination time. The experimental design was completely randomized, in a 2 x 6 factorial scheme, totaling twelve treatments, with four replicates of 50 seeds each, in both trials. Water stress negatively affects the performance of A. deflexus seeds, reducing germination and vigor from -0.1 MPa. Seed germination was compromised by the absence of light, regardless of the applied stress levels. There was an increase in seed germination after application of the same at higher levels of water stress
Substrates on the cuttings rooting of black pepper genotypes
Get PDFThe soil in the production of clonal seedlings of black pepper (Piper nigrum L.) contributes to fusarium and nematodes infestation in commercial crops, and thus the usage of alternative substrates might be a preventive control measure against these pathogens. The aim of this study was to investigate the rhizogenic behavior of the cultivars Bragantina, Iaçará and Guajarina of black pepper in different substrates. The experimental design was in randomized blocks in a 3x4 factorial design (cultivars: Bragantina, Iaçará and Guajarina x substrates: soil + organic compound (18%), vermiculite, carbonized rice hulls and commercial substrate), with four replications of 16 cuttings each. The evaluated characteristics were: survival (%); rooting (basal or nodal) (%); nodal rooting (%); basal rooting (%); number of nodal roots; number of basal roots; total number of roots; length of the largest nodal root (cm); basal root length (cm); nodal root volume (cm3); basal root volume (cm3); Total root volume (cm3); nodal root dry mass (mg); basal root dry mass (mg) and the total root dry mass (mg). There are differences within black pepper cultivars as to the characteristics related to the root system. The vermiculite substrate was the most suitable, and carbonized rice hull is not recommended for the adventitious rooting of cuttings of cultivars Bragantina, Iaçará and Guajarina.The soil in the production of clonal seedlings of black pepper (Piper nigrum L.) contributes to fusarium and nematodes infestation in commercial crops, and thus the usage of alternative substrates might be a preventive control measure against these pathogens. The aim of this study was to investigate the rhizogenic behavior of the cultivars Bragantina, Iaçará and Guajarina of black pepper in different substrates. The experimental design was in randomized blocks in a 3x4 factorial design (cultivars: Bragantina, Iaçará and Guajarina x substrates: soil + organic compound (18%), vermiculite, carbonized rice hulls and commercial substrate), with four replications of 16 cuttings each. The evaluated characteristics were: survival (%); rooting (basal or nodal) (%); nodal rooting (%); basal rooting (%); number of nodal roots; number of basal roots; total number of roots; length of the largest nodal root (cm); basal root length (cm); nodal root volume (cm3); basal root volume (cm3); Total root volume (cm3); nodal root dry mass (mg); basal root dry mass (mg) and the total root dry mass (mg). There are differences within black pepper cultivars as to the characteristics related to the root system. The vermiculite substrate was the most suitable, and carbonized rice hull is not recommended for the adventitious rooting of cuttings of cultivars Bragantina, Iaçará and Guajarina
Fertilization with monoammonium phosphate in the production of Formosa ‘Tainung-01’ papaya in the potiguar semiarid
Get PDFThe achievement of good productivity and quality of fruits is directly associated with a balanced fertilization, in which phosphate fertilizers have an important role in the agricultural production system. In this context, this work aimed to evaluate the effect of doses of monoammonium phosphate in ground fertilization and associated with the topdressing in the production of the Formosa “Tainung-01” papaya. The experimental design was in complete randomized blocks, in an split plots outline, having as main factor four fertilizer doses in ground fertilization (0; 80; 160, and 250 kg ha-1 of monoammonium phosphate [MAP]) and, as a sub-portion, two fertilizers in topdressing (20 kg ha-1 of Cosmofert® + 45 kg ha-1 of MAP” and “90 kg ha-1 of MAP). The harvesting began in the eighth month and extended until the 12th month after transplanting of the seedlings. All fruits of five plants per experimental unit were collected and classified. The number of fruits, the production per plant, the yield, and the percentage of marketable fruits were evaluated. The ground fertilization with the monoammonium phosphate did not influence the production of Formosa \u27Tainung-01\u27 papaya fruits exclusively destined to the domestic market. When the production is destined to the external market, a dosage of 74.0 kg ha-1 of monoammonium phosphate can be used in ground fertilization.The achievement of good productivity and quality of fruits is directly associated with a balanced fertilization, in which phosphate fertilizers have an important role in the agricultural production system. In this context, this work aimed to evaluate the effect of doses of monoammonium phosphate in ground fertilization and associated with the topdressing in the production of the Formosa “Tainung-01” papaya. The experimental design was in complete randomized blocks, in an split plots outline, having as main factor four fertilizer doses in ground fertilization (0; 80; 160, and 250 kg ha-1 of monoammonium phosphate [MAP]) and, as a sub-portion, two fertilizers in topdressing (20 kg ha-1 of Cosmofert® + 45 kg ha-1 of MAP” and “90 kg ha-1 of MAP). The harvesting began in the eighth month and extended until the 12th month after transplanting of the seedlings. All fruits of five plants per experimental unit were collected and classified. The number of fruits, the production per plant, the yield, and the percentage of marketable fruits were evaluated. The ground fertilization with the monoammonium phosphate did not influence the production of Formosa \u27Tainung-01\u27 papaya fruits exclusively destined to the domestic market. When the production is destined to the external market, a dosage of 74.0 kg ha-1 of monoammonium phosphate can be used in ground fertilization