Pub Date : 2022-01-01DOI: 10.1590/1983-40632022v5271672
K. S. Guirra, S. B. Torres, Leomara Vieira de França Cardozo, J. E. B. D. Silva, Bruno Silva Guirra
ABSTRACT The adoption of technologies that allow the mitigation of environmental stresses, such as the use of regulators in seed treatment, is an alternative for crops in high temperatures regions. This study aimed to assess the heat stress mitigation on the germination and initial development of carrot seedlings using plant growth regulators. The study was divided into three experiments performed at the temperatures of 25, 30 and 35 °C. A 5 × 3 factorial arrangement was used, with fve carrot cultivars (Alvorada, Brasília, BRS Esplanada, Tellus and Tropical) and two products (Stimulate® and thiamethoxam), in addition to the control (untreated seeds). The following variables were evaluated: germination, first germination count, seedling length and dry mass. When the cultivars had their seeds treated with the plant growth regulators at 25 °C, the germination for the Tellus cultivar was 28 % higher than for the control, while, at 30 °C, the seed germination for BRS Esplanada and Tellus was twice as high as for the control, and showed a higher vigor than that of Alvorada, Brasília and Tropical. Overall, the thiamethoxam promoted increments at the initial development of carrot seedlings at 25 and 30 °C. However, the germination of the carrot cultivars was disrupted at 35 °C.
{"title":"Heat stress mitigation on the germination and initial development of carrot seedlings using plant growth regulators1","authors":"K. S. Guirra, S. B. Torres, Leomara Vieira de França Cardozo, J. E. B. D. Silva, Bruno Silva Guirra","doi":"10.1590/1983-40632022v5271672","DOIUrl":"https://doi.org/10.1590/1983-40632022v5271672","url":null,"abstract":"ABSTRACT The adoption of technologies that allow the mitigation of environmental stresses, such as the use of regulators in seed treatment, is an alternative for crops in high temperatures regions. This study aimed to assess the heat stress mitigation on the germination and initial development of carrot seedlings using plant growth regulators. The study was divided into three experiments performed at the temperatures of 25, 30 and 35 °C. A 5 × 3 factorial arrangement was used, with fve carrot cultivars (Alvorada, Brasília, BRS Esplanada, Tellus and Tropical) and two products (Stimulate® and thiamethoxam), in addition to the control (untreated seeds). The following variables were evaluated: germination, first germination count, seedling length and dry mass. When the cultivars had their seeds treated with the plant growth regulators at 25 °C, the germination for the Tellus cultivar was 28 % higher than for the control, while, at 30 °C, the seed germination for BRS Esplanada and Tellus was twice as high as for the control, and showed a higher vigor than that of Alvorada, Brasília and Tropical. Overall, the thiamethoxam promoted increments at the initial development of carrot seedlings at 25 and 30 °C. However, the germination of the carrot cultivars was disrupted at 35 °C.","PeriodicalId":46867,"journal":{"name":"Pesquisa Agropecuaria Tropical","volume":"35 1","pages":""},"PeriodicalIF":1.0,"publicationDate":"2022-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"67251415","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-01-01DOI: 10.1590/1983-40632022v5271746
Marlene Carolina Pedroza-Padilla, Kevin Alejandro Rodríguez-Arévalo, L. J. Rincón-Rivera, A. González-Almario
ABSTRACT The role of the Co-52 and Co-42 alleles in the early activation of bean immunity against Colletotrichum lindemuthianum is poorly known. Thus, by using the anthracnose-susceptible Sutagao cultivar and the anthracnose-resistant bean G2333, this study aimed to evaluate the presence of the Co-42 and Co-52 alleles by SCAR markers, as well as their role in the respective defense responses, using histochemical tests and diferential gene expression. The results showed that the Co-52 allele contributes to defense responses against anthracnose, since susceptible beans with the Co-42 allele and without the Co-52 allele decreased both the number of callose deposits and the accumulation of reactive oxygen species at the fungus attack sites. Additionally, for the Sutagao cultivar, there was a late response of defense-related genes such as PR-1, PR-3 and Pv-POD. The Co-52 allele contributes to induce defense mechanisms in the Phaseolus vulgaris and C. lindemuthianum interaction.
{"title":"Co-52 resistance allele contributes to induce basal defense against Colletotrichum lindemuthianum race 7","authors":"Marlene Carolina Pedroza-Padilla, Kevin Alejandro Rodríguez-Arévalo, L. J. Rincón-Rivera, A. González-Almario","doi":"10.1590/1983-40632022v5271746","DOIUrl":"https://doi.org/10.1590/1983-40632022v5271746","url":null,"abstract":"ABSTRACT The role of the Co-52 and Co-42 alleles in the early activation of bean immunity against Colletotrichum lindemuthianum is poorly known. Thus, by using the anthracnose-susceptible Sutagao cultivar and the anthracnose-resistant bean G2333, this study aimed to evaluate the presence of the Co-42 and Co-52 alleles by SCAR markers, as well as their role in the respective defense responses, using histochemical tests and diferential gene expression. The results showed that the Co-52 allele contributes to defense responses against anthracnose, since susceptible beans with the Co-42 allele and without the Co-52 allele decreased both the number of callose deposits and the accumulation of reactive oxygen species at the fungus attack sites. Additionally, for the Sutagao cultivar, there was a late response of defense-related genes such as PR-1, PR-3 and Pv-POD. The Co-52 allele contributes to induce defense mechanisms in the Phaseolus vulgaris and C. lindemuthianum interaction.","PeriodicalId":46867,"journal":{"name":"Pesquisa Agropecuaria Tropical","volume":"61 1","pages":""},"PeriodicalIF":1.0,"publicationDate":"2022-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"67251430","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-01-01DOI: 10.1590/1983-40632022v5272023
L. F. Damaso, C. L. P. Resende, D. D. C. Carvalho, F. D. C. Silva, F. Rodrigues
ABSTRACT A serious problem in fresh corn growing regions is the low availability of phosphorus (P), especially in the Cerrado (Brazilian Savanna) biome. This study aimed to evaluate the performance of experimental double hybrids of fresh corn intended to in natura consumption grown under low and high P availability. A randomized blocks experimental design was used, in a 2 × 21 factorial arrangement, consisting of two P availabilities (37.5 and 75 mg dm−3 of P2O5) and 21 corn hybrids, with 9 replications. The following variables were evaluated: ear insertion height, plant height, male and female flowering, ear length and diameter, grain weight, husked and unhusked ear weight. The best quality and yield for the corn market focused on in natura consumption were observed for the experimental double hybrids DH94 and DH102 under low P availability and for DH71 and DH81 under high P availability. The DH81 hybrid performs better for the consumer market, regardless of the P availability, and, therefore, has versatility and aptitude for this market and for different technological levels.
{"title":"Experimental double hybrids of fresh corn grown under low and high phosphorus availability","authors":"L. F. Damaso, C. L. P. Resende, D. D. C. Carvalho, F. D. C. Silva, F. Rodrigues","doi":"10.1590/1983-40632022v5272023","DOIUrl":"https://doi.org/10.1590/1983-40632022v5272023","url":null,"abstract":"ABSTRACT A serious problem in fresh corn growing regions is the low availability of phosphorus (P), especially in the Cerrado (Brazilian Savanna) biome. This study aimed to evaluate the performance of experimental double hybrids of fresh corn intended to in natura consumption grown under low and high P availability. A randomized blocks experimental design was used, in a 2 × 21 factorial arrangement, consisting of two P availabilities (37.5 and 75 mg dm−3 of P2O5) and 21 corn hybrids, with 9 replications. The following variables were evaluated: ear insertion height, plant height, male and female flowering, ear length and diameter, grain weight, husked and unhusked ear weight. The best quality and yield for the corn market focused on in natura consumption were observed for the experimental double hybrids DH94 and DH102 under low P availability and for DH71 and DH81 under high P availability. The DH81 hybrid performs better for the consumer market, regardless of the P availability, and, therefore, has versatility and aptitude for this market and for different technological levels.","PeriodicalId":46867,"journal":{"name":"Pesquisa Agropecuaria Tropical","volume":"1 1","pages":""},"PeriodicalIF":1.0,"publicationDate":"2022-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"67251012","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-01-01DOI: 10.1590/1983-40632022v5272425
Antonio Carlos Reis de Freitas, G. Souza, E. G. Gomes, Falberni de Souza Costa, D. Klepker
ABSTRACT The low-carbon agriculture is one of the central themes in the climate agenda. This study aimed to evaluate the performance of a low carbon farm in the Maranhão State, Brazil, using univariate and multidimensional approaches. The experimental design consisted of three replications of five treatments (land uses) (Cerrado as a reference area; no-tillage soybean-off-season corn; no-tillage corn-soybean-off-season corn; no-tillage corn-soybean; no-tillage soybean-off-season corn-Brachiarya brizantha), in five periods (Julian days: 28, 48, 83, 138 and 154), totaling 75 observations. The data were analyzed using univariate and multidimensional approaches. A statistically significant interaction was observed between treatment and period, indicating that the responses to the treatment vary with time. The plot that showed the best performance was the reference area, followed by the no-tillage soybean-off-season corn treatment.
{"title":"Performance of low carbon intensified agriculture farm in the Brazilian Savanna by means of univariate and multivariate approaches","authors":"Antonio Carlos Reis de Freitas, G. Souza, E. G. Gomes, Falberni de Souza Costa, D. Klepker","doi":"10.1590/1983-40632022v5272425","DOIUrl":"https://doi.org/10.1590/1983-40632022v5272425","url":null,"abstract":"ABSTRACT The low-carbon agriculture is one of the central themes in the climate agenda. This study aimed to evaluate the performance of a low carbon farm in the Maranhão State, Brazil, using univariate and multidimensional approaches. The experimental design consisted of three replications of five treatments (land uses) (Cerrado as a reference area; no-tillage soybean-off-season corn; no-tillage corn-soybean-off-season corn; no-tillage corn-soybean; no-tillage soybean-off-season corn-Brachiarya brizantha), in five periods (Julian days: 28, 48, 83, 138 and 154), totaling 75 observations. The data were analyzed using univariate and multidimensional approaches. A statistically significant interaction was observed between treatment and period, indicating that the responses to the treatment vary with time. The plot that showed the best performance was the reference area, followed by the no-tillage soybean-off-season corn treatment.","PeriodicalId":46867,"journal":{"name":"Pesquisa Agropecuaria Tropical","volume":"1 1","pages":""},"PeriodicalIF":1.0,"publicationDate":"2022-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"67251294","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-01-01DOI: 10.1590/1983-40632022v5273107
Lara Cristina Pereira da Silva Pacheco, J. S. D. Sousa, V. S. D. Souza Júnior, V. Damin
ABSTRACT Oxyfluorfen is a pre-emergent herbicide applied via soil; however, the soil attributes have not been considered to predict the herbicide doses. This study aimed to evaluate the bioavailability of the oxyfluorfen herbicide in Brazilian Savanna soils with contrasting attributes. The experiment was carried out in a 6 x 8 factorial scheme, with 6 replications. The evaluated factors were soil types [Gleissolo Melânico distrófico - GMd (Typic Humaquept); Latossolo Vermelho ácrico - LVw (Rhodic Acrustox); Latossolo Vermelho distrófico - LVd (Rhodic Haplustox); Neossolo Quartzarênico órtico - RQo (Typic Quartzpsamment); Neossolo Flúvico Tb distrófico - RYbd (Fluventic Dystrustept); and washed sand] and oxyfluorfen doses (0; 360; 480; 720; 1,440; 2,880; 4,320; and 5,760 g a.i. ha-1). The herbicide bioavailability was determined according to the bioassay methodology. The dose that provided 80 % of Cucumis sativum control (C80%) ranged from 9.9 (LVw) to 1,884.4 g a.i. ha-1 (GMd), what can be attributed to the high sorption of the herbicide in the GMd, as observed by the adsorptive rate. The soil texture did not show correlation with the oxyfluorfen bioavailability. In the LVd, which is from the same order and with texture similar to that of the LVw, the C80% was 76 times higher (754.28 g a.i. ha-1). Furthermore, for the RYbd, which is a sandy soil, the C80% was even high (1,256.9 g a.i. ha-1). The cation exchange capacity (CEC) (-0.83**) was the only soil attribute able to predict the herbicide bioavailability. The oxyfluorfen bioavailability is highly dependent on the soil attributes, and, in Brazilian Savanna soils, it can be predicted using the CEC.
{"title":"Oxyfluorfen bioavailability in Brazilian Savanna soils","authors":"Lara Cristina Pereira da Silva Pacheco, J. S. D. Sousa, V. S. D. Souza Júnior, V. Damin","doi":"10.1590/1983-40632022v5273107","DOIUrl":"https://doi.org/10.1590/1983-40632022v5273107","url":null,"abstract":"ABSTRACT Oxyfluorfen is a pre-emergent herbicide applied via soil; however, the soil attributes have not been considered to predict the herbicide doses. This study aimed to evaluate the bioavailability of the oxyfluorfen herbicide in Brazilian Savanna soils with contrasting attributes. The experiment was carried out in a 6 x 8 factorial scheme, with 6 replications. The evaluated factors were soil types [Gleissolo Melânico distrófico - GMd (Typic Humaquept); Latossolo Vermelho ácrico - LVw (Rhodic Acrustox); Latossolo Vermelho distrófico - LVd (Rhodic Haplustox); Neossolo Quartzarênico órtico - RQo (Typic Quartzpsamment); Neossolo Flúvico Tb distrófico - RYbd (Fluventic Dystrustept); and washed sand] and oxyfluorfen doses (0; 360; 480; 720; 1,440; 2,880; 4,320; and 5,760 g a.i. ha-1). The herbicide bioavailability was determined according to the bioassay methodology. The dose that provided 80 % of Cucumis sativum control (C80%) ranged from 9.9 (LVw) to 1,884.4 g a.i. ha-1 (GMd), what can be attributed to the high sorption of the herbicide in the GMd, as observed by the adsorptive rate. The soil texture did not show correlation with the oxyfluorfen bioavailability. In the LVd, which is from the same order and with texture similar to that of the LVw, the C80% was 76 times higher (754.28 g a.i. ha-1). Furthermore, for the RYbd, which is a sandy soil, the C80% was even high (1,256.9 g a.i. ha-1). The cation exchange capacity (CEC) (-0.83**) was the only soil attribute able to predict the herbicide bioavailability. The oxyfluorfen bioavailability is highly dependent on the soil attributes, and, in Brazilian Savanna soils, it can be predicted using the CEC.","PeriodicalId":46867,"journal":{"name":"Pesquisa Agropecuaria Tropical","volume":"1 1","pages":""},"PeriodicalIF":1.0,"publicationDate":"2022-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"67251733","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-01-01DOI: 10.1590/1983-40632022v5272707
K. C. I. Sousa, A. A. Chaibub, J. C. B. Carvalho, M. C. Filippi, L. G. Araújo
ABSTRACT The BRS Tropical rice cultivar was developed for tropical foodplains, but is susceptible to sheath blight, making the Waitea circinata bioagent an important tool in managing the disease. This study aimed to assess the W. circinata mechanisms involved in the parasitism and resistance induction to sheath blight. The in vitro antagonism was assessed by optical microscopy and scanning electron microscopy, followed by quantification of the lytic enzymes involved in parasitism, such as chitinase, glucanase and protease. An effect of the W. circinata mycoparasite against Rhizoctonia solani was observed. The W. circinata application suppressed the sheath blight by up to 65 % and increased the chitinase, glucanase and lipoxygenase activity 72 h after the inoculation and that of the peroxidase 96 h after the inoculation. Thus, W. circinata showed to be efficient in suppressing sheath blight by parasitism and induced resistance via the activation of biochemical mechanisms.
{"title":"Mechanisms involved in the biocontrol of rice sheath blight by Waitea circinata","authors":"K. C. I. Sousa, A. A. Chaibub, J. C. B. Carvalho, M. C. Filippi, L. G. Araújo","doi":"10.1590/1983-40632022v5272707","DOIUrl":"https://doi.org/10.1590/1983-40632022v5272707","url":null,"abstract":"ABSTRACT The BRS Tropical rice cultivar was developed for tropical foodplains, but is susceptible to sheath blight, making the Waitea circinata bioagent an important tool in managing the disease. This study aimed to assess the W. circinata mechanisms involved in the parasitism and resistance induction to sheath blight. The in vitro antagonism was assessed by optical microscopy and scanning electron microscopy, followed by quantification of the lytic enzymes involved in parasitism, such as chitinase, glucanase and protease. An effect of the W. circinata mycoparasite against Rhizoctonia solani was observed. The W. circinata application suppressed the sheath blight by up to 65 % and increased the chitinase, glucanase and lipoxygenase activity 72 h after the inoculation and that of the peroxidase 96 h after the inoculation. Thus, W. circinata showed to be efficient in suppressing sheath blight by parasitism and induced resistance via the activation of biochemical mechanisms.","PeriodicalId":46867,"journal":{"name":"Pesquisa Agropecuaria Tropical","volume":"1 1","pages":""},"PeriodicalIF":1.0,"publicationDate":"2022-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"67251780","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-01-01DOI: 10.1590/1983-40632022v5273265
Cyntia Stephânia dos Santos, F. A. C. Pereira, J. Mauri, Mariana Thereza Rodrigues Viana, G. C. Rodrigues, A. Veiga, G. F. Bartholo, Milene Alves de Figueiredo Carvalho
ABSTRACT The knowledge on cultivars is essential for parental choosing on breeding programs. This research aimed to study the genetic divergence of Coffea arabica L. cultivars from a germoplasm bank of the Embrapa Cerrados, Brazil, for leaf anatomic and physiological characteristics. A total of 23 cultivars were evaluated: Acaiá Cerrado MG1474, Araponga MG1, Catiguá MG1, Catiguá MG2, Catiguá MG3, Catiguá MG3 P4, Catiguá MG3 P5, Catiguá MG3 P7, Catiguá MG3 P9, Catiguá MG3 P23, Catiguá MG3 P51, Catuaí Amarelo IAC 62, Catuaí Vermelho IAC 15, Catuaí Vermelho IAC 81, Catuaí Vermelho IAC 99, Caturra Vermelho MG0187, Guatenano Colis MG0207, Mundo Novo IAC 379-19, Paraíso MG1, Pau Brasil MG1, Sacramento MG1, San Ramon MG0198 and Topázio MG1190. In addition to the genetic divergence, the broad sense heritability and coefficient of genetic and environmental variation were also evaluated. All characteristics showed high coefficients of genetic variation and heritability values greater than 70 %, indicating a predominance of genetic over environmental factors, and that these are characteristics likely to obtain genetic gain. Catiguá MG1, Catiguá MG3 P51 and Topázio MG1190 stood out, with superior gas exchange characteristics. Attributes related to gas exchange were important for cultivar differentiation, demonstrating that they can be used in the early selection of Coffea arabica L. genotypes.
{"title":"Assessment of leaf anatomic and physiological characteristics and genetic divergence among Coffea arabica L. cultivars in the Brazilian Savanna","authors":"Cyntia Stephânia dos Santos, F. A. C. Pereira, J. Mauri, Mariana Thereza Rodrigues Viana, G. C. Rodrigues, A. Veiga, G. F. Bartholo, Milene Alves de Figueiredo Carvalho","doi":"10.1590/1983-40632022v5273265","DOIUrl":"https://doi.org/10.1590/1983-40632022v5273265","url":null,"abstract":"ABSTRACT The knowledge on cultivars is essential for parental choosing on breeding programs. This research aimed to study the genetic divergence of Coffea arabica L. cultivars from a germoplasm bank of the Embrapa Cerrados, Brazil, for leaf anatomic and physiological characteristics. A total of 23 cultivars were evaluated: Acaiá Cerrado MG1474, Araponga MG1, Catiguá MG1, Catiguá MG2, Catiguá MG3, Catiguá MG3 P4, Catiguá MG3 P5, Catiguá MG3 P7, Catiguá MG3 P9, Catiguá MG3 P23, Catiguá MG3 P51, Catuaí Amarelo IAC 62, Catuaí Vermelho IAC 15, Catuaí Vermelho IAC 81, Catuaí Vermelho IAC 99, Caturra Vermelho MG0187, Guatenano Colis MG0207, Mundo Novo IAC 379-19, Paraíso MG1, Pau Brasil MG1, Sacramento MG1, San Ramon MG0198 and Topázio MG1190. In addition to the genetic divergence, the broad sense heritability and coefficient of genetic and environmental variation were also evaluated. All characteristics showed high coefficients of genetic variation and heritability values greater than 70 %, indicating a predominance of genetic over environmental factors, and that these are characteristics likely to obtain genetic gain. Catiguá MG1, Catiguá MG3 P51 and Topázio MG1190 stood out, with superior gas exchange characteristics. Attributes related to gas exchange were important for cultivar differentiation, demonstrating that they can be used in the early selection of Coffea arabica L. genotypes.","PeriodicalId":46867,"journal":{"name":"Pesquisa Agropecuaria Tropical","volume":"1 1","pages":""},"PeriodicalIF":1.0,"publicationDate":"2022-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"67251789","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-01-01DOI: 10.1590/1983-40632022v5272730
S. Muda, B. Lakitan, A. Wijaya, S. Susilawati
ABSTRACT Alternanthera sissoo is currently propagated using stem or terminal cuttings, since it does not produce fertile seeds. This research aimed to identify the most effective propagation planting material among rooted stump, stem cutting and terminal cutting, as well as their response to the application of NPK fertilizer. The results showed a better performance for stem cutting than for rooted stump or apical cutting. The canopy area was positively related to the longest diameter (R2 = 0.92) and the average of two-way cross-sectional diameter (R2 = 0.89). The number of branches, branch fresh weight, leaf fresh and dry weights did not vary among the planting materials; however, the total number of leaves, branch and root dry weights were higher for stem cutting. Stem cutting is also available in a larger quantity than the other two planting materials when collected from each mother plant. Therefore, it is recommended for optimizing leaf yield in A. sissoo. The species positively responded to NPK fertilization, as shown by the increase of the SPAD value for 6 to 12 days after the initial application. Therefore, for maximizing yield, it should be regularly fertilized with NPK every 3 weeks, coinciding with the time that the SPAD index falls back to pre-NPK application levels.
{"title":"Response of Brazilian spinach (Alternanthera sissoo) to propagation planting material and NPK fertilizer application","authors":"S. Muda, B. Lakitan, A. Wijaya, S. Susilawati","doi":"10.1590/1983-40632022v5272730","DOIUrl":"https://doi.org/10.1590/1983-40632022v5272730","url":null,"abstract":"ABSTRACT Alternanthera sissoo is currently propagated using stem or terminal cuttings, since it does not produce fertile seeds. This research aimed to identify the most effective propagation planting material among rooted stump, stem cutting and terminal cutting, as well as their response to the application of NPK fertilizer. The results showed a better performance for stem cutting than for rooted stump or apical cutting. The canopy area was positively related to the longest diameter (R2 = 0.92) and the average of two-way cross-sectional diameter (R2 = 0.89). The number of branches, branch fresh weight, leaf fresh and dry weights did not vary among the planting materials; however, the total number of leaves, branch and root dry weights were higher for stem cutting. Stem cutting is also available in a larger quantity than the other two planting materials when collected from each mother plant. Therefore, it is recommended for optimizing leaf yield in A. sissoo. The species positively responded to NPK fertilization, as shown by the increase of the SPAD value for 6 to 12 days after the initial application. Therefore, for maximizing yield, it should be regularly fertilized with NPK every 3 weeks, coinciding with the time that the SPAD index falls back to pre-NPK application levels.","PeriodicalId":46867,"journal":{"name":"Pesquisa Agropecuaria Tropical","volume":"1 1","pages":""},"PeriodicalIF":1.0,"publicationDate":"2022-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"67251895","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-01-01DOI: 10.1590/1983-40632022v5270048
D. Benedito, L. C. D. Freitas
ABSTRACT Forest stands managed with the coppicing technique tend to display a decreased production in subsequent rotations, demanding high stump sprouting rates, so that the planting succeeds. This study aimed to assess the vigour of eucalyptus sprouts on the basis of stumps diameter and height. The number of sprouts and height of the highest sprout were assessed regarding the stumps diameter, providing the following treatments: stumps smaller than 12 cm in diameter; from 12 to 15 cm; from 15.1 to 18 cm; and larger than 18 cm. The number of sprouts was also assessed as a function of the cutting height of the stumps, providing the following treatments: stumps near the ground and at 5, 10 and 15 cm above the ground. The diameter of the stumps did not influence the amount of sprouts, but exerted influence on the height of the highest sprout after 120 and 150 days of resprouting. The stump height had a great influence on the number of sprouts, indicating that, despite reducing the volume of timber harvested, the highest stumps provided expressive gains in the stand regeneration. The cutting height and stumps diameter influence the sprouting vigour of eucalyptus clones managed by the coppicing system.
{"title":"Influence of the stump diameter and height on the growth and vigor of eucalyptus sprouts","authors":"D. Benedito, L. C. D. Freitas","doi":"10.1590/1983-40632022v5270048","DOIUrl":"https://doi.org/10.1590/1983-40632022v5270048","url":null,"abstract":"ABSTRACT Forest stands managed with the coppicing technique tend to display a decreased production in subsequent rotations, demanding high stump sprouting rates, so that the planting succeeds. This study aimed to assess the vigour of eucalyptus sprouts on the basis of stumps diameter and height. The number of sprouts and height of the highest sprout were assessed regarding the stumps diameter, providing the following treatments: stumps smaller than 12 cm in diameter; from 12 to 15 cm; from 15.1 to 18 cm; and larger than 18 cm. The number of sprouts was also assessed as a function of the cutting height of the stumps, providing the following treatments: stumps near the ground and at 5, 10 and 15 cm above the ground. The diameter of the stumps did not influence the amount of sprouts, but exerted influence on the height of the highest sprout after 120 and 150 days of resprouting. The stump height had a great influence on the number of sprouts, indicating that, despite reducing the volume of timber harvested, the highest stumps provided expressive gains in the stand regeneration. The cutting height and stumps diameter influence the sprouting vigour of eucalyptus clones managed by the coppicing system.","PeriodicalId":46867,"journal":{"name":"Pesquisa Agropecuaria Tropical","volume":"1 1","pages":""},"PeriodicalIF":1.0,"publicationDate":"2022-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"67250696","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-01-01DOI: 10.1590/1983-40632022v5270513
S. S. Souza, Pedro Afonso Couto Júnior, J. A. Flôres, A. P. Coelho, L. B. Lemos
ABSTRACT Depending on the climate and soil conditions and management, the intercropping of maize with soil cover plants may reduce the cereal agronomic performance. This study aimed to assess the effects of intercropping with Urochloa ruziziensis and Crotalaria spectabilis on the maize agronomic performance and the straw production and quality after the harvest. Three treatments (single maize and maize intercropped with U. ruziziensis and with C. spectabilis) were distributed into a randomized blocks design. The growth and production components and the maize grain yield were evaluated in the three systems, as well as the straw production and nitrogen accumulation in each system. The intercropping systems did not decrease the maize yield and agronomic performance, if compared to the single crop, regardless of the evaluated species. The intercropping with C. spectabilis and U. ruziziensis presented a straw production 24 and 11 % higher, respectively, and the intercropping with C. spectabilis resulted in a straw nitrogen accumulation 39 % higher, when compared to the single maize crop.
{"title":"Do the intercropping with Crotalaria spectabilis and Urochloa ruziziensis reduce the maize agronomic performance?","authors":"S. S. Souza, Pedro Afonso Couto Júnior, J. A. Flôres, A. P. Coelho, L. B. Lemos","doi":"10.1590/1983-40632022v5270513","DOIUrl":"https://doi.org/10.1590/1983-40632022v5270513","url":null,"abstract":"ABSTRACT Depending on the climate and soil conditions and management, the intercropping of maize with soil cover plants may reduce the cereal agronomic performance. This study aimed to assess the effects of intercropping with Urochloa ruziziensis and Crotalaria spectabilis on the maize agronomic performance and the straw production and quality after the harvest. Three treatments (single maize and maize intercropped with U. ruziziensis and with C. spectabilis) were distributed into a randomized blocks design. The growth and production components and the maize grain yield were evaluated in the three systems, as well as the straw production and nitrogen accumulation in each system. The intercropping systems did not decrease the maize yield and agronomic performance, if compared to the single crop, regardless of the evaluated species. The intercropping with C. spectabilis and U. ruziziensis presented a straw production 24 and 11 % higher, respectively, and the intercropping with C. spectabilis resulted in a straw nitrogen accumulation 39 % higher, when compared to the single maize crop.","PeriodicalId":46867,"journal":{"name":"Pesquisa Agropecuaria Tropical","volume":"1 1","pages":""},"PeriodicalIF":1.0,"publicationDate":"2022-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"67250797","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}