‘CL151’ a Clearfield long-grain rice cultivar, was released in 2008, based upon excellent agronomic characteristics, including excellent yield and moderately resistant rating for lodging. Further experience has indicated it’s susceptibility to lodging. Lodging can reduce harvest efficiency, yield, and cause grain quality loss. The purpose of this research was to evaluate multiple management practices such as nitrogen rates and timings, seeding rate, trinexapac-ethyl application, potassium, and fungicide application to mitigate lodging for CL151. The results of this research indicate that N rate and application timing largely influence lodging incidence and grain yield. Fungicide application decreased, but did not eliminate lodging, while potassium application did not impact lodging or grain yield. Seeding rate also has a significant impact on grain yield and lodging incidence. Trinexapac-ethyl also decreased lodging incidence, but negatively impacted grain yield which was most evident when applied at 48 g ha-1 and applied at PD +14d growth stage.

A preliminary experiment evaluated the effect of plant growth regulators (PGRs) or mechanical stimulation (brushing) on branching of sweet basil (Ocimum basilicum L.), cilantro (Coriandrum sativium L.), and parsley (Petroselinum crispum (Mill.) Nyman ex A.W. Hill). Dikegulac sodium increased branching in sweet basil up to 400 ppm and thereafter branching decreased compared to control plants. Ethephon increased branching in sweet basil as rate increased up to 500 mg/L compared to control plants. Mechanical stimulation resulted in a significant decrease in plant height, plant width, number of branches, and number of leaders for all species compared to control plants. Benzyladenine and metaconazole had no effect on these species. In the main experiment the effect of colored shade cloth and PGRs or brushing were assessed on sweet basil, Thai basil (Ocimum basilicum "Siam Queen" L.), Genovese basil (Ocimum basilicum "Genovese" L.), cilantro, and parsley. All crops were grown under conventional black, blue ChromatiNet®, or red ChromatiNet® shade cloth. Subplot treatments included: dikegulac sodium at 400 ppm; benzyladenine at 300 ppm; ethephon at 350 ppm; brushing at 10 strokes applied twice daily. We assessed volatile compunds on all crops and conducted a sensory panel on sweet basil. Red shade cloth increased the number of branches and shoot fresh weight in sweet basil, Thai basil, and Genovese basil. Number of leaf stalks and shoot fresh weight also increased in cilantro plants grown under red shade cloth. Red shade cloth increased fresh weight of parsley plants. Sensory panel results showed a preference for the appearance of sweet basil grown under red shade cloth. Red shade cloth can be used to grow sweet basil, Thai basil, Genovese basil, cilantro, and parsley plants that have more branches and higher fresh weights. / Master of Science

As espécies Cattleya labiata Lindley e a Cattleya eldorado Linden, nativas da Mata Atlântica e Amazônia, respectivamente, encontram-se sob forte risco de desaparecimento na natureza, sendo, portanto, necessário o desenvolvimento de métodos eficientes de propagação de suas mudas, dentre os quais se destaca a micropropagação. A eficiência do cultivo in vitro de orquídeas está associada aos meios de cultura utilizados e, principalmente, aos reguladores de crescimento. O trabalho teve como objetivo avaliar a influência de paclobutrazol (PBZ) no desenvolvimento das microplântulas cultivadas in vitro. Plântulas provenientes de germinação in vitro, com 1,0 ± 0,2 cm de comprimento, foram utilizadas no estudo. No primeiro experimento, utilizou-se como controle o meio de cultura MS isento de reguladores de crescimento vegetal. Nos tratamentos, o meio MS foi suplementado com quatro concentrações de PBZ 1,0; 2,0; 4,0 e 6,0 mg.L-1; com ácido naftalenoacético (ANA) 1,0 mg.L-1 associado a 6-benzilaminopurina (BAP) 1,0 mg.L-1 e com a combinação de 4,0 mg.L-1 PBZ, com 1,0 mg.L-1 ANA e 1,0 mg.L-1 BAP. As avaliações morfológicas, número de brotos, comprimento da parte aérea (CPA), comprimento da maior raiz (CMR) e comprimento da lâmina foliar (CLF), foram realizadas no início do experimento e nos subcultivos a cada 40 dias, durante 160 dias. O delineamento experimental foi inteiramente casualizado em arranjo trifatorial com parcelas subdivididas no tempo, com seis repetições por tratamento. Um segundo experimento foi realizado utilizando a técnica de pulse. Como controle foi utilizado meio de cultura MS, e para os tratamentos foi utilizado o mesmo meio acrescido de concentrações crescentes de PBZ com diferentes tempos de exposição, sendo: T0= controle (MS); T1= 1,0 mg.L-1 PBZ por 40 dias; T2= 10,0 mg.L-1 PBZ por 4 dias e T3= 100,0 mg.L-1 PBZ por 4 horas. Foram feitas as avaliações de CPA, CLF, CMR, número de raízes, massa fresca e massa seca da parte aérea, massa fresca e massa seca de raiz, massa fresca e massa seca total, contagem e caracterização estomática e avaliação anatômica do tecido radicular. O experimento foi conduzido no delineamento inteiramente casualizado totalizando quatorze repetições por tratamento. O tratamento com 1,0 mg.L-1 de PBZ por 40 dias promoveu maior desenvolvimento e vigor do sistema radicular, aumentando a espessura das raízes, podendo contribuir para a fase de aclimatização das microplântulas. Os tratamentos com pulse reduziram significativamente a parte aérea das microplântulas, não sendo recomendado na micropropagação da C. labiata. / The Species Cattleya labiata Lindley and Cattleya eldorado Linden, native to the Atlantic Forest and Amazon, respectively, are under high risk of extinction in nature, therefore, necessary to develop efficient methods of spreading their seedlings, among which highlights micropropagation. The efficiency of in vitro cultivation of orchids is associated with culture media, and especially the growth regulators. The study aimed to evaluate the influence of paclobutrazol (PBZ) in the development of in vitro microplantlets. Seedlings from germination in vitro, with 1.0 ± 0.2 cm in length, were used in the study. In the first experiment, we used to control the MS culture medium free of plant growth regulators. In the treatments, MS medium was supplemented with four concentrations of PBZ 1.0, 2.0, 4.0 and 6.0 mg L-1, with naphthaleneacetic acid (NAA) 1.0 mg L-1 associated with 6-benzylaminopurine (BAP) 1.0 mg L-1 and with the combination of 4.0 mg L-1 PBZ with 1.0 mg.L-1 NAA and 1.0 mg L-1 BAP. The morphological evaluations, number of shoots, shoot length (CPA), longest root length (CMR) and leaf blade length (CLF) were performed at the beginning of the experiment and in subcultures every 40 days during 160 days. The experimental design was completely randomized in three-factor split-plot arrangement in time, with six replicates per treatment. A second experiment was performed using the technique of \"pulse\". It was used as control MS medium, and the treatments we used the same medium plus increasing concentrations of PBZ with different exposure times, as follows: T0 = control (MS), T1 = 1.0 mg L-1 PBZ for 40 days, T2 = 10.0 mg L-1 PBZ for 4 days and T3 = 100.0 mg L-1 PBZ for 4 hours. Assessments were made CPA, CLF, CMR, number of roots, fresh and dry mass of shoots, fresh weight and dry weight of root, fresh weight and total dry matter, stomatal counting and characterization and evaluation of the anatomic root tissue. The experiment was conducted in a completely randomized a total of fourteen replicates per treatment. Treatment with 1.0 mg L-1 of PBZ for 40 days promoted further development and vigor of the root system, increasing the thickness of the roots and may contribute to the acclimatization phase of microplantlets. Treatments with \"pulse\" significantly reduced the shoot microplantlets and Its not recommended to the micropropagation of C. labiata.

Com o objetivo de estudar o comportamento fenológico, morfológico e produtivo de cultivares de algodoeiro com diferentes arquiteturas de plantas em diferentes espaçamentos, através do manejo com regulador de crescimento, foi realizado o presente trabalho, na área experimental da ESALQ/USP, no município de Piracicaba, Estado de São Paulo, no ano agrícola de 2000/01. O delineamento experimental utilizado foi o de blocos ao acaso com parcelas sub-subdivididas e 4 repetições. As parcelas constituíram-se dos espaçamentos de 0,76 e 1,01 m, as subparcelas das três cultivares (IAC 23, DeltaOpal e CD 401) e as sub-subparcelas em presença ou ausência de regulador de crescimento. Em seis plantas marcadas de cada parcela foram analisados os seguintes parâmetros: acompanhamento das fases fenológicas (emergência, aparecimento do primeiro botão floral, antese da primeira flor e abertura do primeiro capulho) e caracteres agronômicos de campo (altura de planta, diâmetro do caule, número de ramos vegetativos e frutíferos, conformação da planta, número de capulhos por planta e altura de inserção do primeiro ramo frutífero). Na área útil de cada parcela foi determinada, a produção de algodão em caroço por hectare e a precocidade de colheita. Em amostras de 20 capulhos tomadas aleatoriamente em cada parcela foram realizadas as análises dos caracteres agronômicos de laboratório (massa de 100 sementes, porcentagem de fibras e massa média de um capulho) e das características tecnológicas da fibra (comprimento, uniformidade de comprimento, maturidade, tenacidade e índice micronaire). Os resultados obtidos permitem concluir que não houve interações significativas para as cultivares x espaçamentos x regulador de crescimento, para a produção de algodão em caroço, precocidade de colheita, caracteres agronômicos de laboratório e características tecnológicas das fibras, com exceção da tenacidade. Desta forma, as cultivares avaliadas, independente da arquitetura da planta, apresentaram capacidade de ajustar-se às variações dos espaçamentos testados e aplicação de regulador de crescimento com relação a estas características. Os caracteres agronômicos de campo como: a altura das plantas e o diâmetro de caule, de modo geral, apresentaram médias reduzidas com a redução do espaçamento e aplicação do regulador de crescimento, para as cultivares de desenvolvimento mais vigoroso (IAC 23 e DeltaOpal), não influenciando, porém, a cultivar de plantas morfologicamente mais compactas (CD 401). / The purpose of this work was to study the phenological, morphological and productive behavior of cotton cultivars presenting different plant shapes under different spacing layouts managed with the use of plant growth regulator. The experiment was established in the experimental field of ESALQ/USP, Piracicaba, Sao Paulo, during the 2000/01 growing season and was arranged in a randomized block experimental design with subdivided plots and 4 replications. The plots represented spacing layouts of 0.76 and 1.01 m, subplots consisted of the IAC 23, DeltaOpal and CD 401 cultivars, while the sub-subplots were characterized by the use or absence of growth regulator. Six plants per plot were labeled and analyzed for the phenological phases (emergence, appearance of the first flower bud, anthesis of the first flower, opening of the first cotton boll) and field agronomical characteristics (plant height, stem diameter, number of vegetative and fruit branches, plant shape, number of cotton boll per plant and insertion height of the first fruit branch). The harvest early and raw cotton yield per hectare were determined considering the effective plot area. The agronomical lab characteristics (mass of 100 seeds, fiber percentage and cotton boll mass), as well as the fiber technological characteristics (length, length uniformity, maturity, strength, and micronaire) were analyzed using a sample of 20 bolls taken at random. Based on the results obtained, it can be concluded that there were no significant interactions among cultivars x spacing x growth regulator, as to cotton yield, harvest early, agronomical lab characteristics and fiber technological characteristics, except for stremgth. The analyzed cultivars, regardless of the plant shape, showed good adaptation to the variation in spacing layouts, as well as to the application of growth regulator, considering the analyzed characteristics. The field agronomical characteristics, such as plant height and stem diameter, generally decreased with the reduction in spacing and with the application of growth regulator, considering the most vigorous cultivars (IAC 23 and DeltaOpal). On the other hand, the cultivar presenting a more compact plant (CD 401) pattern was not influenced by spacing or use of growth regulator.

O emprego de reguladores vegetais como maturadores da cana-de-açúcar tem sido uma prática bem utilizada, em virtude da necessidade de antecipação da colheita e da otimização do planejamento agrícola. Contudo, com a freqüente disponibilidade de genótipos de cana-de-açúcar pelos programas de melhoramento, pouca informação se tem das interações entre novos genótipos e produtos sobre a qualidade tecnológica. Este estudo objetivou determinar a resposta de sete genótipos de cana-de-açúcar à aplicação de dois reguladores vegetais quanto à influência na qualidade da matéria prima. O ensaio foi instalado em março de 2004 e conduzido na APTA Regional Centro-Oeste, Jaú (SP). O delineamento experimental foi o de blocos casualizados, em parcelas sub-divididas, com quatro repetições, constituído pela combinação dos genótipos IAC87-3396, IAC87-3410, IAC89-3124, IAC91-2195, IAC91-5155, PO88-62 e SP80-1842, e de três manejos de condução da maturação sulfometuron metil, 20 g p. c. ha-1; etefon, 2,0 l p. c. ha-1 e testemunha. A qualidade tecnológica foi determinada através dos atributos Brix no caldo, pol no caldo, pureza do caldo, fibra da cana, pol na cana, açúcares redutores no caldo, açúcares redutores na cana e açúcar total recuperável (ATR) aos 0, 21, 42, 63, 84, 105 e 126 dias após a aplicação (DAA), além dos atributos florescimento, "isoporização", produtividade de colmos e de açúcar aos 126 DAA. Observou-se que, para a maioria dos genótipos, o emprego dos maturadores antecipou a colheita em 21 dias em relação à testemunha, sendo o etefon indicado para colheita entre 42 e 84 DAA, e o sulfometuron metil para o período entre 105 e 126 DAA. O IAC91-5155 não respondeu aos maturadores, o PO88-62 apresentou melhor resposta ao sulfometuron metil, e os demais genótipos ao uso de etefon, quanto à qualidade tecnológica. Os dois produtos, etefon e sulfometuron metil, controlaram o florescimento. Os genótipos IAC91-5155 e PO88-62, apesar de não florescidos, apresentaram "isoporização". Para a maioria dos genótipos a aplicação dos maturadores não afetou a produtividade de colmos, exceto para o sulfometuron metil que reduziu a do genótipo SP80-1842, e para etefon que aumentou a do IAC91-2195. O sulfometuron metil e o etefon aumentaram a produtividade de açúcar do genótipo IAC89- 3124. O IAC91-2195 apresentou produtividade de açúcar maior com a aplicação de etefon. A produtividade de açúcar foi menor no SP80-1842 com o emprego de sulfometuron metil. / Use of plant growth regulators as sugarcane ripeners has been a practice well used, because of the need of early harvest and the agricultural planning optimization of the crop. However, with the frequent release of genotypes by breeding programs, little information is available about of the interactions among new genotypes and products over the technological quality. This study aimed to determine the response of seven sugarcane genotypes to the application of two ripeners in the raw material quality. The experiment was installed in march 2004 and carried out in the APTA Regional Center West, Jaú (SP). The experimental design was the randomized complete blocks, in split-plot, with four repetitions, constituted by the genotypes IAC87-3396, IAC87-3410, IAC89-3124, IAC91- 2195, IAC91-5155, PO88-62 and SP80-1842, and by three ripening manegement sulfometuron methyl, 20 g p. c. ha-1; ethephon, 2,0 l p.c. ha-1 and control. The technological attributes evaluated were Brix in the juice, pol in the juice, purity of the juice, fiber of the cane, juice reducing sugars, stalks reducing sugars and recoverable total sugars (ATR) to 0, 21, 42, 63, 84, 105 and 126 days after the application (DAA) besides flowering, pith, productivity of stalks and sugar attributes to 126 DAA. It was observed that for the most of the genotypes the use of ripeners antecipated the harvest in 21 days in relation to control, being ethephon recomendable for harvest between 42 and 84 DAA, and sulfometuron methyl for the period between 105 and 126 DAA. The genotype IAC91-5155 didn't answer to the ripeners, PO88-62 presented better answer to sulfometuron methyl and the others genotypes to ethephon to technological quality. Both products, ethephon and sulfomethuron methyl, controlled the flowering. The genotypes IAC91-5155 and PO88-62, in spite of no flowering, presented pith. For most of the genotypes the application of the ripeners didn't affect the productivity of stalks, except to sulfomethuron methyl that reduced it in SP80- 1842, and to ethephon that increased it in IAC91-2195. Sulfomethuron methyl and ethephon increased the productivity of sugar of the genotype IAC89-3124. IAC91-2195 presented bigger sugar productivity with ethephon application. The productivity of sugar was smaller in SP80-1842 with sulfomethuron methyl use.

Submitted by Maria Beatriz Vieira (mbeatriz.vieira@gmail.com) on 2017-03-28T13:22:07Z No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) dissertacao_igor_tonin.pdf: 373470 bytes, checksum: a238602334cacca2e05e75ae1da2e45a (MD5) / Approved for entry into archive by Aline Batista (alinehb.ufpel@gmail.com) on 2017-04-05T17:37:40Z (GMT) No. of bitstreams: 2 dissertacao_igor_tonin.pdf: 373470 bytes, checksum: a238602334cacca2e05e75ae1da2e45a (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Approved for entry into archive by Aline Batista (alinehb.ufpel@gmail.com) on 2017-04-05T17:38:40Z (GMT) No. of bitstreams: 2 dissertacao_igor_tonin.pdf: 373470 bytes, checksum: a238602334cacca2e05e75ae1da2e45a (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Made available in DSpace on 2017-04-05T17:38:50Z (GMT). No. of bitstreams: 2 dissertacao_igor_tonin.pdf: 373470 bytes, checksum: a238602334cacca2e05e75ae1da2e45a (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Previous issue date: 2015-09-08 / Sem bolsa / O trigo (Triticum aestivum L.) é uma cultura de destaque econômico e um dos cereais de inverno mais cultivados no sul do Brasil. Entretanto, suas sementes apresentam dormência, sendo um fator limitante em programas de melhoramento genético, quando se deseja rápida germinação pós-colheita, necessitando dessa forma, viabilizar tecnologias para potencializar a germinação. A pesquisa teve como objetivo avaliar a eficácia de doses de ácido giberélico na superação de dormência de sementes de trigo. As sementes de trigo da cultivar TBIO Toruk foram tratadas com inseticida Cropstar imidacloprid+thiodicarb 600 SC), fungicida Spectro (difenoconazol 150 SC) seguido de adição na calda do TS de GA3 nas respectivas dosagens. Os tratamentos empregados consistiram em doses de ácido giberélico, sendo: Pro-Gibb® (50 mg Kg-1 de GA3); Pro-Gibb® (100 mg Kg-1 de GA3); Pro-Gibb® (150 mg Kg-1 de GA3); Pro-Gibb® (200 mg Kg-1 de GA3); Pro-Gibb® (250 mg Kg-1 de GA3); Pro-Gibb® (300 mg Kg-1 de GA3) e testemunha (semente sem tratamento). Para avaliar a eficácia do GA3 as variáveis analisadas foram germinação, primeira contagem da germinação, velocidade de germinação, índice e coeficiente de velocidade de germinação. Os resultados obtidos permitem concluir que o ácido giberélico influenciou de forma positiva na superação da dormência de sementes de trigo, onde foi constatado maior porcentagem de germinação e vigor. A dose de ácido giberélico de 50 mg Kg-1, propiciou maior porcentagem de germinação (91 %), com incremento de 35 % na germinação de sementes de trigo quando comparado com sementes não tratadas. Por outro lado, constatou-se que doses de ácido giberélico, acima de 250 mg Kg-1, não são recomendadas para superação de dormência de sementes de trigo. / Wheat (Triticum aestivum L.) is a crop that has highlight of economic and one of the most important winter cereals grown in southern Brazil. However, the seeds present dormancy, limiting factor in breeding programs, considering that is necessary germination immediately after the harvest, requiring viable technologies to enhance germination. The research aimed to evaluate the effectiveness of gibberellic acid doses in overcoming wheat seed dormancy, It was used wheat seeds cultivar TBIO Toruk, Were treated with Cropstar insecticide (imidacloprid + thiodicarb 600 SC), Spectro fungicide (difenoconazole 150 SC) followed by the addition of the TS with GA3 in the dosis evaluated. The treatments consisted in the use of gibberellic acid doses, as follows: Pro-Gibb® (50 mg Kg-1 GA3); Pro-Gibb® (100 mg Kg-1 GA3); Pro- Gibb® (150 mg Kg-1 GA3); Pro-Gibb® (200 mg Kg-1 GA3); Pro-Gibb® (250 mg Kg-1 GA3); Pro-Gibb® (300 mg Kg-1 GA3) and Witness without treatment. To evaluate the effectiveness of GA3 it was analyzed the variables: germination, first germination count, germination rate, index and coefficient of germination speed. The obtained results allow us to conclude that gibberellic acid positively influenced the physiological quality of wheat seeds, where was found greater percentage of germination and vigor. A gibberellic acid dose of 50 mg Kg-1, show greater germination percentage (91 %), an increase of 35 % in wheat seeds germination when compared to untreated seeds. Gibberellic acid doses above 250 mg Kg-1, are not recommended for overcoming wheat seed dormancy.

Orientador: Ciro Antonio Rosolem / Banca: João Domingues Rodrigues / Banca: Luiz Henrique Carvalho / Resumo: O experimento foi conduzido de janeiro a abril de 2007 sob condições de casa de vegetação. O objetivo foi avaliar o comportamento de cultivares de algodão submetidas a doses de cloreto de mepiquat e, ainda, verificar se a resposta está ligada ao ciclo ou arquitetura da cultivar. Os tratamentos foram constituídos de seis cultivares com comportamento de crescimento e diferentes ciclos produtivos (FiberMax 966, FiberMax 977, DeltaPenta, DeltaOpal, FMT 501 e FMT 701), bem como, a utilização de quatro doses do regulador vegetal a base de cloreto de mepiquat (PIX®): 7,5; 15,0 e 22,5 g ha-1 de i.a e a testemunha sem aplicação do produto. Foram utilizados vasos de 12 litros de capacidade, sendo cultivadas duas plantas por vaso. O delineamento experimental utilizado foi em blocos casualizados com quatro repetições em esquema fatorial 4 doses x 6 cultivares. As avaliações constituíram da: altura de plantas, número de ramos reprodutivos, massa de matéria fresca e massa de matéria seca, retenção de estruturas reprodutivas e área foliar. Para cada cultivar, foi calculada a relação entre taxa de crescimento em altura e concentração do regulador. Os resultados mostraram que o crescimento das plantas de algodoeiro em altura é diminuído com a aplicação foliar de cloreto de mepiquat, sendo maior a redução de altura, quanto maior a quantidade de regulador aplicada. Existe diferença entre as cultivares estudadas quanto à sensibilidade ao regulador, de modo que as mais precoces são mais sensíveis. Para a mesma dose aplicada, a concentração de regulador vegetal na planta é diferente, pois a quantidade de produto depositada na folha de cada cultivar é também diferente. O regulador não afetou a taxa de assimilação de CO2 das cultivares de algodão estudadas. / Abstract: The experiment was conducted between January and April 2007 under greenhouse conditions. The objective to evaluate the behavior of cotton cultivars submitted to the doses of Mepiquat Chloride, and also to find if the answer is linked to the cycle or architecture of cultivar. The treatments were constituted of six cultivars of different behaviour about its growth and cycle (FiberMax 966, FiberMax 977, DeltaPenta, DeltaOpal, FMT 501 e FMT 701); and four doses of the plant growth regulator, mepiquat chloride (PIX®): 7,5, 15,0, 22,5 g ha-1 and a control (0,0 g ha-1). Plots of 12 liters of capacity were used with two plants per plot. The experimental design used was the completely randomized with four replications in outline factorial 4 doses x 6 cultivars. The parameters analyzed were: height of plants, number of reproductive branches, weight of dry matter, retention of reproductive structures, and leaf area. Also, it was calculated for each cultivar, the relationship among growth rate in height and concentration of the regulator. The results showed that the growth of cotton plants in height is reduced by application of mepiquat chloride, and the height reduction is larger, as larger the amount of plant growth regulator applied. There is difference among the cultivars studied for sensitivity to the plant growth regulator, so that the earliest cultivars are more sensitive. In the same applied dose, the concentration of plant growth regulator in the plant is different because the amount of product deposited on the left of each cultivar is different too. The mepiquat chloride didn't affect the assimilation rate of CO2 to the cotton cultivars studied. / Mestre

Genetically modified cotton (Gossypium hirsutum L.) acreage has increased dramatically over the last six years. Reports of variable results in fiber quality and yield have arisen in these cultivars. Some changes in production practices have occurred coincident with the introduction of transgenic technology, such as reduced use of broad-spectrum insecticides, including organophosphates (OP) that could potentially influence the growth and yield of cotton. One factor that might affect these parameters is the difference in the amount of foliarly-applied phosphorus (P) between an OP and non-phosphate (NP) insecticide regime. Therefore, a study was conducted to investigate selected growth characteristics, yield, and fiber quality of genetically modified and conventional cotton as influenced by OP and foliar phosphorus (FP) applications. A four replication strip-plot experimental design was utilized with cultivar serving as the whole plot and insecticide regime as the sub-plot. Three cultivars of the same recurrent parent (ST4892BR, ST4793R, and ST474) were planted in 2001 and 2002 under irrigated conditions in Burleson County, TX on a Weswood silty clay loam (fine-silty, mixed, thermic Fluventic Ustochrept). The insecticide regime consisted of NP, NP+FP, and OP treatments. The FP was applied at P2O5 weight equivalent to the P component in the concurrent OP application. ST4892BR had greater lint yield than ST4793R and ST474. The yield increase can be explained through plant mapping analysis which showed ST4892BR producing larger bolls and greater boll numbers. In addition, evaluation of fruiting distribution showed ST4892BR contained more lint on sympodial branches 6 through 10. The insecticide regime effect on lint yield resulted in higher yield (P=0.08) for the NP+FP regime. Examination of yield components revealed NP+FP increased second position bolls, predominantly at sympodial branches 6 through 10. Leaf tissue analysis revealed increased levels of P for the OP and NP+FP over that of the NP insecticide regime, which indicates a potential for plants to acquire P from OP insecticides. Furthermore, the considerable yield response to small amounts of FP is not clearly understood. While conclusive evidence exists regarding cultivar yield differences, this study does not provide sufficient evidence to conclude that OP insecticides influence growth, yield, or fiber quality characteristics of these cotton cultivars.

Genetically modified cotton (Gossypium hirsutum L.) acreage has increased dramatically over the last six years. Reports of variable results in fiber quality and yield have arisen in these cultivars. Some changes in production practices have occurred coincident with the introduction of transgenic technology, such as reduced use of broad-spectrum insecticides, including organophosphates (OP) that could potentially influence the growth and yield of cotton. One factor that might affect these parameters is the difference in the amount of foliarly-applied phosphorus (P) between an OP and non-phosphate (NP) insecticide regime. Therefore, a study was conducted to investigate selected growth characteristics, yield, and fiber quality of genetically modified and conventional cotton as influenced by OP and foliar phosphorus (FP) applications. A four replication strip-plot experimental design was utilized with cultivar serving as the whole plot and insecticide regime as the sub-plot. Three cultivars of the same recurrent parent (ST4892BR, ST4793R, and ST474) were planted in 2001 and 2002 under irrigated conditions in Burleson County, TX on a Weswood silty clay loam (fine-silty, mixed, thermic Fluventic Ustochrept). The insecticide regime consisted of NP, NP+FP, and OP treatments. The FP was applied at P2O5 weight equivalent to the P component in the concurrent OP application. ST4892BR had greater lint yield than ST4793R and ST474. The yield increase can be explained through plant mapping analysis which showed ST4892BR producing larger bolls and greater boll numbers. In addition, evaluation of fruiting distribution showed ST4892BR contained more lint on sympodial branches 6 through 10. The insecticide regime effect on lint yield resulted in higher yield (P=0.08) for the NP+FP regime. Examination of yield components revealed NP+FP increased second position bolls, predominantly at sympodial branches 6 through 10. Leaf tissue analysis revealed increased levels of P for the OP and NP+FP over that of the NP insecticide regime, which indicates a potential for plants to acquire P from OP insecticides. Furthermore, the considerable yield response to small amounts of FP is not clearly understood. While conclusive evidence exists regarding cultivar yield differences, this study does not provide sufficient evidence to conclude that OP insecticides influence growth, yield, or fiber quality characteristics of these cotton cultivars.

Orientador: Orivaldo Arf / Resumo: A utilização de reguladores de crescimento como técnica que permite redução na estatura da planta e consequente fortalecimento dos colmos pode ser uma opção para minimizar o acamamento em plantas, evitando assim, perdas na cultura. Assim propôs o estudo com o objetivo de avaliar o efeito de doses de etil-trinexapac (zero; 37,5; 75,0; 112,5 e 150,0 g ha-1 do i.a) e épocas de aplicação (6ª, 7ª e 8ª folha completamente formada no colmo principal) durante o desenvolvimento da cultura do arroz de terras altas irrigado por aspersão. O delineamento experimental foi o de blocos ao acaso, disposto em esquema fatorial 5x3, com quatro repetições. A pesquisa foi desenvolvida na área experimental da Faculdade de Engenharia – UNESP, Campus de Ilha Solteira - SP, localizada no município de Selvíria – MS, durante o ano agrícola de 2016/17, utilizando o cultivar BRS Esmeralda. Foram avaliados os componentes de produção, altura de plantas, acamamento, produtividade dos grãos, rendimento industrial e viabilidade econômica. Devido a fatores climáticos como chuvas e ventos fortes as vésperas da colheita, parcelas em que não receberam a aplicação do regulador acamaram totalmente. Aplicações por ocasião da oitava folha além de promover maior número de grãos chochos, as doses de 75,0; 112,5 e 150,0 g ha-1 propiciam menores valores para altura de plantas, massa de cem grãos, massa hectolítrica, rendimento de benefício e grãos inteiros, reduzindo a produtividade de grãos, e influenciando negativamente... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The use of growth regulators as a technique that allows reduction in plant height and consequent strengthening of the stalks might be an option for elimination of lodging in plants, thus avoiding losses of the crop. However, the information on the subject is still scarce. Therefore, the study aimed to evaluate the effect of doses (zero; 37,5; 75,0; 112,5 e 150,0 g ha-1 of active ingredient) and times of application of ethyl-trinexapac (6th leaf, 7th leaf and 8th leaf completely formed in the main stem) during the development of the upland rice crop irrigated by sprinkler. The experimental design was randomized complete blocks, arranged in a 5x3 factorial scheme, with four repetitions. It was developed in the experimental area of Engineering University- UNESP at the Ilha Solteira, São Paulo State, Brazil – Campus, located in Selvíria, Mato Grosso do Sul State, Brazil, during the season of 2016/17, using the cultivar BRS Esmeralda. The components of production, plant height, lodging, grain yield, industrial yield and economic viability were evaluated. Due to climatic factors like rains and strong winds on the eve of the harvest, plots in which they did not receive the application of the regulator completely lodging. Applications for the eighth leaf in addition to promoting higher number of dry grains, the doses of 75.0, 112.5 and 150.0 g ha-1 of active ingredient provide lower values for plant height, weight of 100 grains, hectoliter weight, yield of benefit and whole grains, r... (Complete abstract click electronic access below) / Mestre