Amauri Schmitt | Universidade do Estado de Santa Catarina (original) (raw)

Papers by Amauri Schmitt

RESUMO O objetivo deste trabalho foi verificar se os perfilhos podem mitigar os prejuízos ocasion... more RESUMO O objetivo deste trabalho foi verificar se os perfilhos podem mitigar os prejuízos ocasionados pela desfolha do colmo principal em milho. Os experimentos foram implantados em Lages, SC, em 20/10/2006 e 31/10/2008. O delineamento experimental utilizado foi o de blocos ao acaso, com parcelas subdivididas. Na parcela principal, foram testados dois destinos dos perfilhos: manutenção até a colheita e remoção quando o colmo principal apresentava nove folhas expandidas (V9).

Resumo–O objetivo deste trabalho foi verificar se os perfilhos podem mitigar os prejuízos ocasion... more Resumo–O objetivo deste trabalho foi verificar se os perfilhos podem mitigar os prejuízos ocasionados pela desfolha do colmo principal em milho. Os experimentos foram implantados em Lages, SC, em 20/10/2006 e 31/10/2008. O delineamento experimental utilizado foi o de blocos ao acaso, com parcelas subdivididas. Na parcela principal, foram testados dois destinos dos perfilhos: manutenção até a colheita e remoção quando o colmo principal apresentava nove folhas expandidas (V9).

Resumo: A extensão rural tem fundamental importância para a mantença das atividades dentro das un... more Resumo: A extensão rural tem fundamental importância para a mantença das atividades dentro das unidades de produção familiar (UPF) em Santa Catarina. Por meio dela a relação do agricultor com a técnica acontece de forma mais consistente e duradoura.

Abstract As cultivares de milho diferem na resposta ao aumento da densidade de plantas. Este trab... more Abstract As cultivares de milho diferem na resposta ao aumento da densidade de plantas. Este trabalho foi conduzido para avaliar os efeitos do incremento da população sobre o rendimento de grãos, produção e alocação de massa seca da cultura, no período crítico à definição do número de grãos externado por área, de híbridos contrastantes quanto a tolerância ao adensamento.

Cienc. Rural, Jan 1, 2008

Ciência Rural, Jan 1, 2008

Even though it is not officially recommended by the research institutes, water removal at tilleri... more Even though it is not officially recommended by the research institutes, water removal at tillering is a management practice frequently used by pre-germinated rice growers in the State of Santa Catarina, aiming to stimulate root growth and to reduce plant lodging. A green-house study was carried out with the objective of evaluate the changes in root and shoot morphological traits promoted by soil drainage at tillering. The experiment was performed in the city of Lages, SC, Brazil. Four water management systems were tested: continuous flooding, water removal at tillering and re-flooding at 7, 14 and 21 days after soil drainage. Two cultivars were evaluated for each irrigation system: 'Epagri 106' (short season) and 'Epagri 109' (long season). The experimental units were 7kg pots disposed in a completely randomized experimental design. The experiment was installed on 09/24/2004, using pre-germinated seeds. The shoot parameters were determined 22 days after soil drainage, when all experimental units were re-flooded. The root parameters were determined after shoot harvesting. The root length, area, volume and dry matter were reduced with the increase in soil drainage period for both cultivars. The water withdraw at tillering did not affect shoot dry matter but it decreased the root/shoot ratio. The number of senesced leaves was higher and plant height was lower in the treatments with the longer drainage period than when the irrigation was continuous. Soil drainage at tillering does not seem to be an effective management practice to enhance root development in the pre-germinated rice production system.

Ciência Rural, Jan 1, 2009

Maize does not have an effective mechanism to compensate empty spaces in the field. Therefore, ti... more Maize does not have an effective mechanism to compensate empty spaces in the field. Therefore, tillering hybrids may be more efficient to use environmental resources, especially under low plant populations. This reserach was carried out aiming to evaluate the agronomic performance of maize hybrids grown at two plant densities, with and without tiller's presence. The experiment was set in Lages, SC, Brazil, during the 2005/2006 and 2006/2007 growing seasons. Three hybrids were tested: AS 1560, Penta and P30F53. Each hybrid was evaluated at the densities of 4 and 7pl m-2, keeping tillers until harvest or removing them when the crop had nine expanded leaves. The percentage of plants with tillers at four growth stages, grain yield and yield components were assessed. Hybrids P30F53 and AS 1560 produced more tillers than Penta at the density of 4pl m-2. Tillers destiny did not affect grain yield during the first growing season. In 2006/2007 tiller maintenance promoted higher grain yield than tiller removal for all hybrids at the lower plant density. The results of this work showed that tiller removal does not enhance maize agronomic performance. Furthermore, they demonstrated that tiller maintenance may increase grain yield when maize is grown under low plant densities.

Ciência Rural, Jan 1, 2012

Historically, tillers have been considered detrimental to maize because they do not produce ears ... more Historically, tillers have been considered detrimental to maize because they do not produce ears and may act as sinks competing for carbohydrates with the main stem. This work was carried out aiming to evaluate the effect of tiller removal on maize grain yield at different sowing dates. The experiment was set during the 2006/07 and 2008/09 growing seasons. A randomized complete block design disposed in split-plots was used. Two sowing dates were tested in the main plots: second half of October (recommended) and second half of December (late). Four tiller's fates were evaluated in the split-plots: tiller removal when the main stem had six expanded leaves (V6), nine expanded leaves (V9), fifteen expanded leaves (V15) and tiller maintenance until harvesting. Hybrid P30F53 was sowed at 55,000 plants ha-1, with a row spacing of 0.7m. The percentage of plants with tillers and the number of tillers per plant were higher when maize was sown in October than in December. There was no grain yield difference between treatments where tillers were preserved and those where they were removed at V6, V9 or V15, regardless of sowing date. Such behavior demonstrates that tillers are not sinks that compromise maize agronomic performance. Furthermore, tillers may contribute positively to grain yield when maize is sown in October.

diadecampo.com.br

Palavras-chave: Zea mays L., perfilhamento, densidade, espaçamento, rendimento de grãos Entre os ... more Palavras-chave: Zea mays L., perfilhamento, densidade, espaçamento, rendimento de grãos Entre os cereais de importância econômica, o milho é o de menor capacidade de perfilhamento . Esta característica decorreu da intensa seleção ao qual foi submetido durante o seu processo evolutivo do teosinto, que priorizou a dominância apical, reduzindo o número de ramificações laterais e concentrando toda a energia da planta no colmo principal .

Ciência Rural, Jan 1, 2006

The optimization of maize production systems in southern Brazil depends on the adequate combinati... more The optimization of maize production systems in southern Brazil depends on the adequate combination between genotype traits and the type of management system. This work was carried out aiming at evaluating the grain yield and gross income of maize cultivars with contrasting genetic variability at different management levels. The experiment was conducted in Lages, SC, using randomized block design with split-plots. Four production systems, equivalent to low (S1), medium (S2), high (S3) and very high (S4) management levels were tested in the main plots. The single-cross hybrid Pioneer 32R21, the double cross hybrid Traktor, and the open-pollinated variety BRS Planalto were assessed in the split-plots. The management systems differed in relation to the quantity and timing of fertilizer application, plant density, row spacing, and water irrigation. The trials were sown in 11/20/2002 and 10/22/2003, under the no-till soil tillage system. Regardless cultivar, maize grain yield and gross income increased with the enhancement in management level, ranging from 1,781 (S1) to 13,848 (S4)kg ha-1 and from 206,00 (S1) to 2,937,00 (S4)R$ ha-1, depending on the cultivar and growing season. The larger genetic variability of the cultivar BRS Planalto did not improve its grain yield when compared to the hybrids in S1. The hybrids were more productive and profitable than the open pollinated variety in S2. The use of a single-cross hybrid promoted the greatest grain yield and gross income in S3 and S4, showing that it is possible to match maximum technical and economic efficiency with a high yield plateau, as long as there is financial condition to invest in cultural practices that optimize maize agronomic performance and genetic potential to explore them.

… Brasileira de Milho …, Jan 1, 2011

Ciência Rural, Jan 1, 2008

The water withdraw is a management practice frequently used by rice growers in the State of Santa... more The water withdraw is a management practice frequently used by rice growers in the State of Santa Catarina, Brazil. The water removal aims at enhancing root development, to prevent lodging and to facilitate harvesting. On the other hand, water removal may stress the crop, reducing the number of tillers, decreasing the number of panicles per area and limiting grain yield. This experiment was performed to evaluate the effects of different periods of soil drainage at tillering on the agronomic traits of rice cultivars with contrasting cycles. The experiment was set in Pouso Redondo, SC, during the growing seasons of 2004/2005 and 2005/2006. Four periods of water drainage were tested: no drainage, soil drainage at tillering and re-flooding at 7, 14 and 21 days after soil drainage. Two cultivars were evaluated for each irrigation system: Epagri 106 (short duration) and Epagri 109 (late duration). Grain yield ranged from 7.833 to 9.239kg ha-1 (2004/2005) and from 3.984 to 9.040kg ha-1 (2005/2006). The water management system at tillering did not affect grain yield, yield components and rice milling yield. High pluvial precipitation during the drainage periods prevented drought, mitigating the effects of water management system on rice grain yield. The cultivar differences in growth cycle did not impact their response to the water management system. Soil drainage periods up to 20 days at tillering do not reduce the pre-germinated paddy rice productivity.

Pesq. agropec. bras., …, Jan 1, 2011

Resumo -O objetivo deste trabalho foi avaliar o efeito de variações no arranjo espacial de planta... more Resumo -O objetivo deste trabalho foi avaliar o efeito de variações no arranjo espacial de plantas sobre o perfilhamento, a área foliar e a produtividade do milho. Os experimentos foram implantados na primavera/ verão dos anos agrícolas 2007/2008 e 2008/2009. Os tratamentos consistiram de quatro densidades (três, cinco, sete e nove plantas por metro quadrado) e de três espaçamentos entre linhas (0,4, 0,7 e 1,0 m). Foram avaliados o índice de área foliar (IAF) e a produtividade de grãos do híbrido P30F53, além da contribuição dos perfílhos para esses caracteres. Em 2007/2008, não houve deficiência hídrica, o IAF na floração foi superior a 7 e os perfilhos contribuíram com 65% do IAF total, na menor densidade de plantas. Nesse ano, a produtividade de grãos (13,7 Mg ha -1 ) não foi afetada pelos tratamentos, e os perfilhos contribuíram com 44% da produtividade, na densidade de três plantas por metro quadrado. Em 2008/2009, houve restrição hídrica na pré-floração e no enchimento de grãos, o que diminuiu o perfilhamento e a contribuição dos perfilhos ao IAF. A produtividade de grãos, nesse ano, aumentou de 9,7 para 11,7 Mg ha -1 com o aumento na densidade de plantas, mas a contribuição dos perfilhos à produtividade foi menor. O perfilhamento aumenta a estabilidade fenotípica da produtividade de grãos frente a variações no arranjo de plantas.

Pesquisa …, Jan 1, 2011

The objective of this work was to evaluate the effect of plant spatial arrangement on maize tille... more The objective of this work was to evaluate the effect of plant spatial arrangement on maize tillering, leaf area, and grain productivity. The experiments were carried out in the spring/summer of the 2007/2008 and 2008/2009 growing seasons. Treatments consisted of four plant densities (three, five, seven, and nine plants per square meter) and three row spacings (0.4, 0.7, and 1.0 m). The leaf area index (LAI) and grain yield of hybrid P30F53 were assessed, as well as the tiller contribution to these characters. In 2007/2008, there was no water deficit, LAI values were higher than 7, and tillers contributed with 65% of total LAI at the lowest plant density. In this year, grain yield average (13.7 Mg ha-1) was not affected by treatments, and tillers contributed with 44% of total yield at the density of three plants per square meter. In 2008/2009, there was water deficit before flowering and during grain filling, which decreased tillering and tiller contribution to LAI. Grain yield in this year increased from 9.7 to 11.7 Mg ha-1 with increasing plant densities, but tiller contribution to grain yield was lower. Tillering increases phenotypic stability of grain productivity to variations in plant spatial arrangement.

… Brasileira de Milho …, Jan 1, 2010

… Brasileira de Milho …, Jan 1, 2010

Revista Brasileira de …, Jan 1, 2010

A senescência foliar lenta na fase reprodutiva é uma característica fisiológica positiva à tolerâ... more A senescência foliar lenta na fase reprodutiva é uma característica fisiológica positiva à tolerância de híbridos de milho ao adensamento. Este trabalho foi conduzido objetivando avaliar o efeito do aumento na população de plantas sobre a área foliar e o rendimento de grãos de híbridos de milho. O trabalho foi conduzido no município de Lages, Santa Catarina, utilizando o delineamento experimental de blocos ao acaso, dispostos em parcelas subdivididas. Na parcela principal, foram avaliados os híbridos Ag 303 e Speed. Nas subparcelas, foram avaliadas cinco populações de planta: 25.000, 50.000, 75.000, 100.000 e 125.000 pl ha -1 . Efetuaram-se cinco avaliações de área foliar, realizadas no espigamento e aos 14, 28, 42 e 56 dias após a primeira avaliação. O rendimento de grãos do híbrido Speed foi maior e mais responsivo ao aumento na população de plantas do que o do Ag 303. O incremento na população reduziu a área foliar dos dois híbridos, em todas as épocas de amostragem. A área foliar do Speed foi maior do que a do Ag 303 durante o período de enchimento de grãos. O híbrido mais tolerante ao adensamento preservou maior área foliar verde após o espigamento. Palavras-chave: Zea mays, senescência, densidade de plantas.

RESUMO O objetivo deste trabalho foi verificar se os perfilhos podem mitigar os prejuízos ocasion... more RESUMO O objetivo deste trabalho foi verificar se os perfilhos podem mitigar os prejuízos ocasionados pela desfolha do colmo principal em milho. Os experimentos foram implantados em Lages, SC, em 20/10/2006 e 31/10/2008. O delineamento experimental utilizado foi o de blocos ao acaso, com parcelas subdivididas. Na parcela principal, foram testados dois destinos dos perfilhos: manutenção até a colheita e remoção quando o colmo principal apresentava nove folhas expandidas (V9).

Resumo–O objetivo deste trabalho foi verificar se os perfilhos podem mitigar os prejuízos ocasion... more Resumo–O objetivo deste trabalho foi verificar se os perfilhos podem mitigar os prejuízos ocasionados pela desfolha do colmo principal em milho. Os experimentos foram implantados em Lages, SC, em 20/10/2006 e 31/10/2008. O delineamento experimental utilizado foi o de blocos ao acaso, com parcelas subdivididas. Na parcela principal, foram testados dois destinos dos perfilhos: manutenção até a colheita e remoção quando o colmo principal apresentava nove folhas expandidas (V9).

Resumo: A extensão rural tem fundamental importância para a mantença das atividades dentro das un... more Resumo: A extensão rural tem fundamental importância para a mantença das atividades dentro das unidades de produção familiar (UPF) em Santa Catarina. Por meio dela a relação do agricultor com a técnica acontece de forma mais consistente e duradoura.

Abstract As cultivares de milho diferem na resposta ao aumento da densidade de plantas. Este trab... more Abstract As cultivares de milho diferem na resposta ao aumento da densidade de plantas. Este trabalho foi conduzido para avaliar os efeitos do incremento da população sobre o rendimento de grãos, produção e alocação de massa seca da cultura, no período crítico à definição do número de grãos externado por área, de híbridos contrastantes quanto a tolerância ao adensamento.

Cienc. Rural, Jan 1, 2008

Ciência Rural, Jan 1, 2008

Even though it is not officially recommended by the research institutes, water removal at tilleri... more Even though it is not officially recommended by the research institutes, water removal at tillering is a management practice frequently used by pre-germinated rice growers in the State of Santa Catarina, aiming to stimulate root growth and to reduce plant lodging. A green-house study was carried out with the objective of evaluate the changes in root and shoot morphological traits promoted by soil drainage at tillering. The experiment was performed in the city of Lages, SC, Brazil. Four water management systems were tested: continuous flooding, water removal at tillering and re-flooding at 7, 14 and 21 days after soil drainage. Two cultivars were evaluated for each irrigation system: 'Epagri 106' (short season) and 'Epagri 109' (long season). The experimental units were 7kg pots disposed in a completely randomized experimental design. The experiment was installed on 09/24/2004, using pre-germinated seeds. The shoot parameters were determined 22 days after soil drainage, when all experimental units were re-flooded. The root parameters were determined after shoot harvesting. The root length, area, volume and dry matter were reduced with the increase in soil drainage period for both cultivars. The water withdraw at tillering did not affect shoot dry matter but it decreased the root/shoot ratio. The number of senesced leaves was higher and plant height was lower in the treatments with the longer drainage period than when the irrigation was continuous. Soil drainage at tillering does not seem to be an effective management practice to enhance root development in the pre-germinated rice production system.

Ciência Rural, Jan 1, 2009

Maize does not have an effective mechanism to compensate empty spaces in the field. Therefore, ti... more Maize does not have an effective mechanism to compensate empty spaces in the field. Therefore, tillering hybrids may be more efficient to use environmental resources, especially under low plant populations. This reserach was carried out aiming to evaluate the agronomic performance of maize hybrids grown at two plant densities, with and without tiller's presence. The experiment was set in Lages, SC, Brazil, during the 2005/2006 and 2006/2007 growing seasons. Three hybrids were tested: AS 1560, Penta and P30F53. Each hybrid was evaluated at the densities of 4 and 7pl m-2, keeping tillers until harvest or removing them when the crop had nine expanded leaves. The percentage of plants with tillers at four growth stages, grain yield and yield components were assessed. Hybrids P30F53 and AS 1560 produced more tillers than Penta at the density of 4pl m-2. Tillers destiny did not affect grain yield during the first growing season. In 2006/2007 tiller maintenance promoted higher grain yield than tiller removal for all hybrids at the lower plant density. The results of this work showed that tiller removal does not enhance maize agronomic performance. Furthermore, they demonstrated that tiller maintenance may increase grain yield when maize is grown under low plant densities.

Ciência Rural, Jan 1, 2012

Historically, tillers have been considered detrimental to maize because they do not produce ears ... more Historically, tillers have been considered detrimental to maize because they do not produce ears and may act as sinks competing for carbohydrates with the main stem. This work was carried out aiming to evaluate the effect of tiller removal on maize grain yield at different sowing dates. The experiment was set during the 2006/07 and 2008/09 growing seasons. A randomized complete block design disposed in split-plots was used. Two sowing dates were tested in the main plots: second half of October (recommended) and second half of December (late). Four tiller's fates were evaluated in the split-plots: tiller removal when the main stem had six expanded leaves (V6), nine expanded leaves (V9), fifteen expanded leaves (V15) and tiller maintenance until harvesting. Hybrid P30F53 was sowed at 55,000 plants ha-1, with a row spacing of 0.7m. The percentage of plants with tillers and the number of tillers per plant were higher when maize was sown in October than in December. There was no grain yield difference between treatments where tillers were preserved and those where they were removed at V6, V9 or V15, regardless of sowing date. Such behavior demonstrates that tillers are not sinks that compromise maize agronomic performance. Furthermore, tillers may contribute positively to grain yield when maize is sown in October.

diadecampo.com.br

Palavras-chave: Zea mays L., perfilhamento, densidade, espaçamento, rendimento de grãos Entre os ... more Palavras-chave: Zea mays L., perfilhamento, densidade, espaçamento, rendimento de grãos Entre os cereais de importância econômica, o milho é o de menor capacidade de perfilhamento . Esta característica decorreu da intensa seleção ao qual foi submetido durante o seu processo evolutivo do teosinto, que priorizou a dominância apical, reduzindo o número de ramificações laterais e concentrando toda a energia da planta no colmo principal .

Ciência Rural, Jan 1, 2006

The optimization of maize production systems in southern Brazil depends on the adequate combinati... more The optimization of maize production systems in southern Brazil depends on the adequate combination between genotype traits and the type of management system. This work was carried out aiming at evaluating the grain yield and gross income of maize cultivars with contrasting genetic variability at different management levels. The experiment was conducted in Lages, SC, using randomized block design with split-plots. Four production systems, equivalent to low (S1), medium (S2), high (S3) and very high (S4) management levels were tested in the main plots. The single-cross hybrid Pioneer 32R21, the double cross hybrid Traktor, and the open-pollinated variety BRS Planalto were assessed in the split-plots. The management systems differed in relation to the quantity and timing of fertilizer application, plant density, row spacing, and water irrigation. The trials were sown in 11/20/2002 and 10/22/2003, under the no-till soil tillage system. Regardless cultivar, maize grain yield and gross income increased with the enhancement in management level, ranging from 1,781 (S1) to 13,848 (S4)kg ha-1 and from 206,00 (S1) to 2,937,00 (S4)R$ ha-1, depending on the cultivar and growing season. The larger genetic variability of the cultivar BRS Planalto did not improve its grain yield when compared to the hybrids in S1. The hybrids were more productive and profitable than the open pollinated variety in S2. The use of a single-cross hybrid promoted the greatest grain yield and gross income in S3 and S4, showing that it is possible to match maximum technical and economic efficiency with a high yield plateau, as long as there is financial condition to invest in cultural practices that optimize maize agronomic performance and genetic potential to explore them.

… Brasileira de Milho …, Jan 1, 2011

Ciência Rural, Jan 1, 2008

The water withdraw is a management practice frequently used by rice growers in the State of Santa... more The water withdraw is a management practice frequently used by rice growers in the State of Santa Catarina, Brazil. The water removal aims at enhancing root development, to prevent lodging and to facilitate harvesting. On the other hand, water removal may stress the crop, reducing the number of tillers, decreasing the number of panicles per area and limiting grain yield. This experiment was performed to evaluate the effects of different periods of soil drainage at tillering on the agronomic traits of rice cultivars with contrasting cycles. The experiment was set in Pouso Redondo, SC, during the growing seasons of 2004/2005 and 2005/2006. Four periods of water drainage were tested: no drainage, soil drainage at tillering and re-flooding at 7, 14 and 21 days after soil drainage. Two cultivars were evaluated for each irrigation system: Epagri 106 (short duration) and Epagri 109 (late duration). Grain yield ranged from 7.833 to 9.239kg ha-1 (2004/2005) and from 3.984 to 9.040kg ha-1 (2005/2006). The water management system at tillering did not affect grain yield, yield components and rice milling yield. High pluvial precipitation during the drainage periods prevented drought, mitigating the effects of water management system on rice grain yield. The cultivar differences in growth cycle did not impact their response to the water management system. Soil drainage periods up to 20 days at tillering do not reduce the pre-germinated paddy rice productivity.

Pesq. agropec. bras., …, Jan 1, 2011

Resumo -O objetivo deste trabalho foi avaliar o efeito de variações no arranjo espacial de planta... more Resumo -O objetivo deste trabalho foi avaliar o efeito de variações no arranjo espacial de plantas sobre o perfilhamento, a área foliar e a produtividade do milho. Os experimentos foram implantados na primavera/ verão dos anos agrícolas 2007/2008 e 2008/2009. Os tratamentos consistiram de quatro densidades (três, cinco, sete e nove plantas por metro quadrado) e de três espaçamentos entre linhas (0,4, 0,7 e 1,0 m). Foram avaliados o índice de área foliar (IAF) e a produtividade de grãos do híbrido P30F53, além da contribuição dos perfílhos para esses caracteres. Em 2007/2008, não houve deficiência hídrica, o IAF na floração foi superior a 7 e os perfilhos contribuíram com 65% do IAF total, na menor densidade de plantas. Nesse ano, a produtividade de grãos (13,7 Mg ha -1 ) não foi afetada pelos tratamentos, e os perfilhos contribuíram com 44% da produtividade, na densidade de três plantas por metro quadrado. Em 2008/2009, houve restrição hídrica na pré-floração e no enchimento de grãos, o que diminuiu o perfilhamento e a contribuição dos perfilhos ao IAF. A produtividade de grãos, nesse ano, aumentou de 9,7 para 11,7 Mg ha -1 com o aumento na densidade de plantas, mas a contribuição dos perfilhos à produtividade foi menor. O perfilhamento aumenta a estabilidade fenotípica da produtividade de grãos frente a variações no arranjo de plantas.

Pesquisa …, Jan 1, 2011

The objective of this work was to evaluate the effect of plant spatial arrangement on maize tille... more The objective of this work was to evaluate the effect of plant spatial arrangement on maize tillering, leaf area, and grain productivity. The experiments were carried out in the spring/summer of the 2007/2008 and 2008/2009 growing seasons. Treatments consisted of four plant densities (three, five, seven, and nine plants per square meter) and three row spacings (0.4, 0.7, and 1.0 m). The leaf area index (LAI) and grain yield of hybrid P30F53 were assessed, as well as the tiller contribution to these characters. In 2007/2008, there was no water deficit, LAI values were higher than 7, and tillers contributed with 65% of total LAI at the lowest plant density. In this year, grain yield average (13.7 Mg ha-1) was not affected by treatments, and tillers contributed with 44% of total yield at the density of three plants per square meter. In 2008/2009, there was water deficit before flowering and during grain filling, which decreased tillering and tiller contribution to LAI. Grain yield in this year increased from 9.7 to 11.7 Mg ha-1 with increasing plant densities, but tiller contribution to grain yield was lower. Tillering increases phenotypic stability of grain productivity to variations in plant spatial arrangement.

… Brasileira de Milho …, Jan 1, 2010

… Brasileira de Milho …, Jan 1, 2010

Revista Brasileira de …, Jan 1, 2010

A senescência foliar lenta na fase reprodutiva é uma característica fisiológica positiva à tolerâ... more A senescência foliar lenta na fase reprodutiva é uma característica fisiológica positiva à tolerância de híbridos de milho ao adensamento. Este trabalho foi conduzido objetivando avaliar o efeito do aumento na população de plantas sobre a área foliar e o rendimento de grãos de híbridos de milho. O trabalho foi conduzido no município de Lages, Santa Catarina, utilizando o delineamento experimental de blocos ao acaso, dispostos em parcelas subdivididas. Na parcela principal, foram avaliados os híbridos Ag 303 e Speed. Nas subparcelas, foram avaliadas cinco populações de planta: 25.000, 50.000, 75.000, 100.000 e 125.000 pl ha -1 . Efetuaram-se cinco avaliações de área foliar, realizadas no espigamento e aos 14, 28, 42 e 56 dias após a primeira avaliação. O rendimento de grãos do híbrido Speed foi maior e mais responsivo ao aumento na população de plantas do que o do Ag 303. O incremento na população reduziu a área foliar dos dois híbridos, em todas as épocas de amostragem. A área foliar do Speed foi maior do que a do Ag 303 durante o período de enchimento de grãos. O híbrido mais tolerante ao adensamento preservou maior área foliar verde após o espigamento. Palavras-chave: Zea mays, senescência, densidade de plantas.