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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Determining the effect of prohexadione calcium growth regulator on growth and yield of peanut [Arachis hypogaea (L.)] in Mississippi

Treadway, Zachary Ray 01 May 2020 (has links)
Studies were conducted in small-plot and onarm environments in Mississippi in 2018 and 2019 to determine the effect of prohexadione calcium growth regulator on the growth and yield of peanut [Arachis hypogaea (L.)]. Onarm trials conducted in 2018 and 2019 concluded that in situations where the application of prohexadione calcium increased yield, variation in application rate had no effect on yield. Yields of peanut where any rate of prohexadione calcium was applied were 415 kg ha-1 greater than yields of peanut where prohexadione calcium were not applied. The addition of other agrichemicals had no effect on the efficacy of prohexadione calcium. Small-plot research in 2019 concluded that no rate variation had any effect on the growth or yield of peanut, and also concluded that alternative application timing methods had no effect on yield or growth of peanut.
2

Novel applications in Mississippi cotton and peanut

Gaudin, Anna Beth 09 August 2022 (has links) (PDF)
Studies were conducted in the field from 2020-2021 in peanut and cotton to optimize peanut growth and yield through prohexadione calcium application methods as well as weed control through increasing herbicide sites of action. These studies were established on multiple on-farm and small-plot locations in Mississippi. Prohexadione calcium studies concluded that following application of prohexadione calcium effects on yield and peanut growth were inconsistent. Neither varying application timing nor rate resulted in peanut yield that was different than when adhering to the label recommendations. Increasing sites of action studies concluded that broadleaf signalgrass and Amaranthus species control was optimized at four SOAs and two SOAs, respectively. Based on this study, the current recommendation of additional SOAs will not result in increased weed control.
3

Uso de fitorreguladores em pomar de abacateiro (Persea americana Mill.) \'Hass\' cultivado em condições de sequeiro / Use of plant growth regulators in \'Hass\' avocado (Persea Americana Mill.) orchards under rainfed conditions

Brogio, Bruna do Amaral 19 May 2017 (has links)
Embora o Brasil apresente grande potencial para a expansão da cultura do abacateiro, sobretudo devido as condições edafoclimáticas favoráveis, sua produção ainda é restrita no país, principalmente devido a fatores limitantes, como a não adoção do adensamento nos pomares comerciais e de manejos agronômicos que favoreçam a produção e qualidade de frutos; a presença de Phytophthora cinnamomi, principal patógeno que afeta a cultura em todo o mundo; o fato da grande maioria dos pomares comerciais serem cultivados sob condições de sequeiro; e devido a fatores inerentes a ecofisiologia da planta, como vigor excessivo, baixa fixação de frutos e a dificuldade em controlar a alternância de produção. A aplicação de fitorreguladores é um manejo importante e com bons resultados, nos pomares comerciais dos principais países produtores, sendo esta uma técnica que visa melhorar a produtividade, incrementar o tamanho dos frutos, diminuir a alternância produtiva e reduzir o vigor vegetativo. O objetivo desta pesquisa foi avaliar o efeito de distintos fitorreguladores no desenvolvimento vegetativo, produção, eficiência e alternância produtiva, tamanho e formato de frutos e na qualidade pós-colheita de abacateiros \'Hass\' não irrigados. Entre 2013 e 2016, foram avaliados sete tratamentos via pulverização foliar: T1: água (testemunha); T2: 250 mg.L-1 Viviful® (68,75 mg.L-1 prohexadione-cálcio); T3: 0,7% Cultar® 250 SC (0,175% paclobutrazol); T4: 0,7% Sunny® (0,035% uniconazole); T5: 1% Moddus® (0,25% etil-trinexapac); T6: 1250 mg.L-1 MaxCel® (25 mg.L-1 6- benziladenina) aplicados no florescimento; e T7: 125 mg.L-1 ProGibb® 400 (50 mg.L-1 ácido giberélico) aplicado no início do mês de dezembro antes da segunda queda natural de frutos. O delineamento experimental foi conduzido em blocos ao acaso, com 7 tratamentos, 4 repetições e 2 plantas por parcela. Nos distintos tratamentos foram avaliados: tamanho da planta; crescimento dos brotos de primavera; produção, tamanho e formato de frutos e a qualidade pós-colheita. Os fitorreguladores utilizados não afetaram significativamente o desenvolvimento vegetativo, a eficiência produtiva e a produção de frutos, bem como não influenciaram na qualidade pós-colheita dos mesmos. O inibidor de giberelina uniconazole (T4) foi o responsável por reduzir significativamente o crescimento dos brotos de primavera durante os três anos de avaliações. A citocinina 6-benziladenina (T6) reduziu de forma significativa a alternância produtiva de abacateiros \'Hass\' enquanto o uniconazole (T4), prohexadione-cálcio (T2) e 6-benziladenina (T6) aumentaram significativamente o tamanho dos frutos. A maioria dos fitorreguladores utilizados modificaram o formato dos frutos, tornando-os mais arredondados, com destaque para o efeito do etil-trinexapac (T5). A aplicação dos distintos fitorreguladores se apresentam inconstantes ao longo dos anos de pesquisa e não afetam número, produção de frutos (Kg.planta-1) e eficiência produtiva de abacateiros \'Hass\' não irrigados. / Although Brazil presents great potential for the expansion of the avocado crop, especially due to the favorable edaphoclimatic conditions, its production is still restricted in the country, mainly due to limiting factors, such as the non-adoption of high-density plantings in commercial orchards and agronomic managements to support high fruit yield and quality; the presence of Phytophthora cinnamomi, the main pathogen affecting avocados around the world; the fact that most of the commercial orchards are grown under rainfed conditions; and also due to factors that are inherent to the tree\'s ecophysiology, such as the excessive vigor, low fruit set and difficulty in controlling the alternate bearing. Plant growth regulators (PGRs) have become important management tools in the commercial orchards of the main producer countries for improving yields, increasing fruit size, reducing alternate bearing and reducing vegetative vigor. The aim of this research was to evaluate the effect of different PGRs on vegetative growth, fruit yield, yield efficiency and alternate bearing, fruit size and shape, and post-harvest quality of \'Hass\' avocados non-irrigated. Between 2013 and 2016, seven treatments were evaluated by foliar sprays : T1: water (control); T2: 250 mg.L-1 Viviful® (68,75 mg.L-1 prohexadione-calcium); T3: 0,7% Cultar® 250 SC (0,175% paclobutrazol); T4: 0,7% Sunny® (0,035% uniconazole); T5: 1% Moddus® (0,25% trinexapac-ethyl); T6: 1250 mg.L-1 MaxCel® (25 mg.L-1 6-benzyladenine) all applied in full bloom; and T7: 125 mg.L-1 ProGibb® 400 (50 mg.L-1 gibberelic acid) applied at the beginning of December, before the second natural fruit drop. The experiment was conducted in a randomized block design with seven treatments, four replications and two plants per plot. The following variables were evaluated: tree size, spring shoot growth, fruit yield, size and shape and post-harvest fruit quality. The applied PGRs did not significantly affect tree size, yield efficiency and fruit yield, nor did they influence the post-harvest fruit quality. Uniconazole (T4) was responsible of a significant shortening of spring shoots during the three years of evaluations. The cytokinin 6-benzyladenine (T6) significantly reduced alternate bearing of \'Hass\' avocado trees. Spring sprays of uniconazole (T4), prohexadione-calcium (T2) and 6-benzyladenine (T6) significantly increased fruit size. Most of the PGRs modified -fruit shape of \'Hass\' avocados to a more rounded format, with trinexapac-ethyl (T5) showing a stronger effect. The application of the different PGRs are inconsistent throughout the years of research and do not affect fruit number and yield (kg.tree-1) and yield efficiency of non-irrigated \'Hass\' avocados.
4

Environmental and endogenous influences on carbohydrate assimilation and allocation of apple trees (Malus domestica Borkh)

Pretorius, Jeremia Jesaja Bierman 04 1900 (has links)
Stellenbosch University. Faculty of AgriSciences. Dept. of Horticulture. / Thesis (PhD (Agric))--Stellenbosch University, 2006. / ENGLISH ABSTRACT: Market preferences for larger fruit have forced producers to adopt cultural practices that will ensure bigger fruit even if this comes at the expense of reduced total yields. In order to obtain acceptable fruit size there must be an adequate supply of photosynthetic carbon products especially during the cell division stage of fruit growth. Competition between fruits and between fruit and vegetative growth, as well as adverse climatic conditions, may limit the carbon supply to the fruits at this critical period and thus limit the final fruit size. Growers are showing renewed interest in the use of girdling or scoring in combination with the usual fruit thinning program to achieve growth control and increase fruit size. A new and milder chemical growth retardant, prohexadione-calcium (ProCa), is now also available for vegetative growth control of apple trees. [n this study, the effects of, and potential interaction between scoring, ProCa and fruit thinning were investigated, with respect to shoot and fruit growth, yield and photosynthetic capacity, in 'Royal Gala" 'Fuji' and 'Cripps' Pink' apple trees. ProCa decreased final extension shoot length in all three cultivars. Extension shoots were generally more sensitive than bourse shoots to scoring and ProCa. ProCa seems to be a more effective way of controlling shoot growth than scoring, with 'Fuji' and 'Cripps' Pink' being more sensitive than 'Royal Gala' to the application of ProCa. Scoring led to increased fruit growth rates during the first 40 days after full bloom (DAFB), and culminated in better fruit size at harvest. Scoring improved the total soluble solids concentration (TSS) of 'Fuji' and 'Cripps' Pink' compared to control and ProCa treatments. ProCa inhibited shoot growth effectively, but no evidence was found for improved carbon allocation to fruits and reproductive buds. Yield efficiencies of scored trees were significantly improved in all cultivars during the second season, due to better reproductive bud development after the first year of scoring. On 'Royal Gala' and 'Cripps' Pink', the efficiency of scoring to stimulate reproductive bud development on old and new spurs declined after 4 weeks after full bloom (WAFB). In 'Fuji', scoring later than I WAFB led to a decreasing positive response on old and new spurs. In contrast, reproductive bud development on long shoots increased with later scoring (6 and 8 W AFB) on all cultivars. It seems that the most beneficial time of scoring is 2-4 W AFB, as early as possible during the cell division stage offruit growth, but not before natural drop has occurred. The combination of early-season scoring and application of ProCa seems to hold potential for increasing carbon allocation to the fruit and improving fruit size and quality attributes. Scoring early in the season reduced photosynthetic capacity, and this reduction in carbon availability led to earlier cessation of shoot growth as well as shorter shoots. Later in the season, reduced fruit numbers led to a decrease in photosynthesis. The optimum temperature range for photosynthesis was found to adjust according to seasonal temperature variations. The harvest-induced reduction in sink strength changed stomatal sensitivity to higher temperature. Due to a reduced demand for carbohydrates by the plant, the maximum rate of photosynthesis (Amax) was reduced post-harvest. Following this reduction in sink strength and Am .. , stomata became more sensitive to high leaf temperatures, thus restricting water loss. Pre-harvest there was a strong demand for carbohydrates, therefore stomata were kept open at higher temperatures to ensure a high rate of C02 incorporation, but at a cost with regard to water use efficiency. The sharp increase in dark respiration (Rd) in leaves and fruit with an increase in temperature would mean that significant carbohydrate shortages could occur in trees during source limited periods early in the season, especially under warm weather conditions commonly experienced in the Western Cape region. / AFRIKAANSE OPSOMMING: Die effek van omgewings- en interne faktore op koolstofproduksie en -allokasie in appelbome (Malus domestlca Borkh.). Mark voorkeur vir groter vrugte forseer produsente om tegnieke te gebruik wat groter vrugte sal verseker selfs al beteken dit verlaagde totale opbrengste. Om aanvaarbare vruggrootte te bereik moet daar voldoende voorsiening van fotosinteties geproduseerde koolstofprodukte aan die vrug wees, veral gedurende die selverdelingstadium van vruggroei. Kompetisie tussen vrugte, en tussen vrugte en vegetatiewe groei sal die voorsiening van koolstof gedurende die kritieke stadium aan die vrug beperk en so vruggroote benadeel. Daar is dus hernude belangstelling in die gebruik van ringelering in kombinasie met die gewone vrug uitdunprogramme om groei te beheer en vruggrootte te verbeter. 'n Nuwe, sagter chemiese groeireguleerder, proheksadioon-kalsium (ProCa) is ook nou beskikbaar vir groeibeheer op appelbome. In hierdie studie is die effekte van, en moontlike interaksie tussen ringelering, ProCa en vruguitdunning ondersoek ten opsigte van loot- en vruggroei en opbrengs, sowel as die effekte op gaswisseling op 'Royal Gala', 'Fuji' en 'Cripps' Pink' appelbome. ProCa veroorsaak korter lote in aJ drie kultivars. Verlengingslote is meer sensitief as beurslote vir ringelering en ProCa. ProCa is effektiewer as ringelering om lootgroei te beheer, en 'Fuji' en 'Cripps' Pink' is sensitiewer as 'Royal Gala'. Ringelering lei tot verbeterde vruggroeitempos gedurende die eerste 40 dae na volblom en verbeterde vruggrootte by oes. Ringelering verbeter die totale oplosbare vastestotkonsentrasie (TOVS) van 'Fuji' en 'Cripps' Pink' in vergelyking met kontrole- en ProCa-behandelings, onderskeideHk. ProCa inhibeer lootgroei effektief, maar geen bewyse van verbeterde koolstomllokasie na vrugte en reproduktiewe knoppe is gevind nie. Opbrengseffektiwiteit van geringeleerde borne verhoog gedurende die tweede seisoen van ringelering weens beter reproduktiewe knopontwikkeling. Ringelering later as 4 weke na volblom (WNVB) is minder effektief om reproduktiewe knopontwikkeling op ou en nuwe spore in 'Royal Gala' en 'Cripps' Pink' te stimuleer. Die positiewe effek van ringelering op reproduktiewe knoppe op 'Fuji' verminder sodra dit later as I WNVB gedoen word. Op langlote het 'n laat ringelering (6 en 8 WNVB) die beste effek op reproduktiewe knopontwikkeling. Die mees voordelige tyd om te ringeIeer was 2-4 WNVB, so vroeg as moontlik gedurende die selverdelingstadium van vruggroei, maar nie voor natuurlike vrugval voltooi is nie. Die kombinasie van vroei! ringelering en die toediening van ProCa het potensiaal om koolstofallokasie na die vrug te verbeter, met die gepaardgaande verbetering in vruggrootte en -kwaliteit. RingeJering vroeg in die seisoen inhibeer fotosintese en hierdie verlaging in koolstof beskikbaarheid het tot gevolg dat lootgroei vroei!r gestaak word. Later in die seisoen veroorsaak verlaagde vruggetalle 'n afname in fotosintese. Die optimum temperatuur vir fotosintese verander na gelang van heersende lugtemperature. Die oes-geinduseerde verlaging in sinksterkte verander stomatale sensitiwiteit vir hoo temperature. Weens 'n verJaagde aanvraag vir koolhidrate deur die plant word fotosintese verlaag na-oes. Weens die verlaging is stomata sensitiewer vir hoer temperature en beperk dus waterverlies. V oor oes is daar 'n hoo aanvraag na koolhidrate dus word stomata oop gehou selfs by hoe temperature ten koste van watergebruiksdoeltreffendheid. Die skerp styging in donker respirasie in blare en vrugte met 'n verhoging in temperature sal beteken dat koolhidraat-tekorte kan ontstaan in bome gedurende die bron-beperkte periodes vroeg in die seisoen, veral onder warm toestande 500S wat algemeen ervaar word in die Wes Kaap.
5

Plant Bioregulator Strategies to Alleviate Biennial Bearing, Enhance Precocity, and Control Vegetative Growth of ‘Northern Spy’ Apple Trees

Duyvelshoff, Christopher 11 May 2011 (has links)
Biennial bearing, low precocity, and vigorous vegetative growth are major production constraints of ‘Northern Spy’ apple trees. Experiments were conducted in bearing and non-bearing ‘Northern Spy’/M.9 orchards to determine whether plant bioregulator applications of ethephon (ETH), napthaleneacetic acid (NAA), prohexadione-calcium (P-Ca), and/or benzyladenine (BA) could be used to overcome these production constraints of ‘Northern Spy’. Ethephon application at 150, 300, or 450 mg∙L-1 in the ‘on’ year increased return bloom, fruit yield, and alleviated biennial bearing in the ‘off’ year in a positive linear relationship to concentration when trees were moderately biennial in cropping. Applications applied 22 June were more effective than 27 July or 31 Aug. applications. However, single or multiple (2, 3, or 4) application(s) of 150 mg∙L-1 ETH or 5 mg∙L-1 NAA were ineffective when trees were not biennial. Two ETH applications at 1500 mg∙L-1 to non-bearing trees significantly increased flowering and fruit yield the year following treatment. The combination of P-Ca with ETH had an additive effect on shoot growth and improved growth control compared to P-Ca alone. Two BA applications at 500 mg∙L-1 had no effect on lateral branching of young trees. / Chudleigh's Limited, MITACS Accelerate
6

Inibidores da biossíntese de giberelina em tomateiro / Inhibitors of gibberelline biosynthesis in tomatoes

Ferraz, Andrew Kim Lopes 22 February 2018 (has links)
Submitted by ANDREW KIM LOPES FERRAZ null (andrewkim.lf@gmail.com) on 2018-04-05T20:59:29Z No. of bitstreams: 1 DISSERTACAO KIM VERSAO FINAL.pdf: 1021141 bytes, checksum: b931d57e66d55af435eddac76a83ff05 (MD5) / Approved for entry into archive by Maria Lucia Martins Frederico null (mlucia@fca.unesp.br) on 2018-04-06T11:47:18Z (GMT) No. of bitstreams: 1 ferraz_akl_me_botfca.pdf: 1021141 bytes, checksum: b931d57e66d55af435eddac76a83ff05 (MD5) / Made available in DSpace on 2018-04-06T11:47:18Z (GMT). No. of bitstreams: 1 ferraz_akl_me_botfca.pdf: 1021141 bytes, checksum: b931d57e66d55af435eddac76a83ff05 (MD5) Previous issue date: 2018-02-22 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / A utilização de reguladores vegetais é uma realidade presente nas mais diversas áreas de cultivo, inclusive na olericultura. Os inibidores da biossíntese do hormônio vegetal giberelina compõe a classe de retardantes de crescimento mais utilizada na agricultura, onde os diversificados produtos disponíveis são atuantes em diversas fases da biossíntese desse hormônio vegetal. Tendo em vista a importância econômica do tomateiro no país, bem como a necessidade de maiores estudos da ação desses produtos em culturas hortícolas, o presente trabalho objetivou averiguar a influência dos inibidores da síntese de giberelina, cloreto de chlormequat (CCC) e prohexadione-Ca (ProCa), na cultura do tomateiro, avaliando a possível atuação no crescimento vegetativo e interferência no desenvolvimento reprodutivo. Foram conduzidos dois experimentos em ambiente protegido na área experimental da Fazenda de Ensino, Pesquisa e Produção de São Manuel, localizada no município de São Manuel (SP), pertencente à Faculdade de Ciências Agronômicas da Universidade Estadual Paulista-UNESP, Campus de Botucatu-SP. Os delineamentos experimentais nos experimentos foram em blocos casualizados. Para o experimento I, os tratamentos consistiram em crescentes concentrações de Cloreto de Chlormequat (CCC): T1 – testemunha (água); T2– CCC a 500 mg i.a. L-1; T3– CCC a 1000 mg i.a. L-1; T4– CCC a 1500 mg i.a. L-1; T5- CCC a 2000 mg i.a. L-1. Para o experimento II, os tratamentos foram compostos de crescentes concentrações de Prohexadione-Ca (ProCa): T1 – testemunha (água); T2– ProCa a 500 mg i.a. L-1; T3– ProCa a 1000 mg i.a. L-1; T4– ProCa a 1500 mg i.a. L-1; T5– ProCa a 2000 mg i.a. L-1. Os tratamentos foram aplicados via foliar na cultura a cada 10 dias. O efeito de ambos os produtos foram avaliados por análises de crescimento, produtividade e produção, quantificação da atividade de enzimas antioxidantes e atributos bioquímicos de pós-colheita. Através dos resultados conclui-se que, para o experimento I, as concentrações de CCC empregadas não apresentaram efeitos positivos ou negativos sobre a cultura. Para o experimento II, as concentrações de ProCa empregadas apresentaram efeitos negativos, reduzindo os atributos de colheita e produtividade, reduzindo também, consideravelmente, o crescimento, além de influenciar no sistema antioxidativo das plantas.
7

Reguladores de crescimento no desenvolvimento de diferentes espécies de grama / Growth regulators on the development and quality of grass species

Queiroz, Juliana Roberta Gobi [UNESP] 04 February 2016 (has links)
Submitted by JULIANA ROBERTA GOBI QUEIROZ null (julianaque@gmail.com) on 2016-03-28T21:06:31Z No. of bitstreams: 1 Juliana Regina Gobi Queiroz tese final.pdf: 1884473 bytes, checksum: 87837c22f3ac5eb237d7d319e1daa775 (MD5) / Approved for entry into archive by Juliano Benedito Ferreira (julianoferreira@reitoria.unesp.br) on 2016-03-29T18:07:42Z (GMT) No. of bitstreams: 1 queiroz_jrg_dr_bot.pdf: 1884473 bytes, checksum: 87837c22f3ac5eb237d7d319e1daa775 (MD5) / Made available in DSpace on 2016-03-29T18:07:42Z (GMT). No. of bitstreams: 1 queiroz_jrg_dr_bot.pdf: 1884473 bytes, checksum: 87837c22f3ac5eb237d7d319e1daa775 (MD5) Previous issue date: 2016-02-04 / Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) / Os gramados podem ser utilizados em diversos ambientes com diferentes propósitos, e possuem características intrínsecas como a espécie de grama utilizada, o nível de manutenção e as técnicas adotadas. O uso de reguladores de crescimento, dentro de um manejo adequado, possibilita uma maior eficiência seja na manutenção ou produção de tapetes de qualidade. Dessa forma, o presente trabalho teve por objetivo avaliar os efeitos de trinexapac-ethyl, piraclostrobina associado ou não ao epoxiconazol e prohexadionecálcio como reguladores vegetais, sobre o crescimento e a qualidade dos tapetes de gramas das espécies Esmeralda (Zoysia japonica Steud.), São Carlos (Axonopus compressus (Sw.) Beauv.) e Bermuda (Cynodon dactylon (L.)). No primeiro estudo, os tratamentos e doses (g i.a. ha-1) testados, com e sem reaplicação foram: trinexapac-ethyl de 113,0 a 226,0, piraclostrobina + epoxiconazol de (66,5+25,0) a (113,0+50), piraclostrobina de 100,0 a 200,0, além de uma testemunha para cada espécie avaliada. No segundo estudo, os tratamentos e doses (g i.a. ha-1) testados, com duas e três reaplicações foram: prohexadione-cálcio de 27,5 a 165,0, além de uma testemunha sem aplicação do regulador de crescimento. Em ambos os estudos, foram realizadas avaliações visuais de fitotoxicidade através de uma escala de notas, na qual, “0” correspondeu a nenhuma injúria demonstrada pelas plantas e “100” a morte das plantas. Também foram avaliados: altura das plantas, número de inflorescências, além da coleta das aparas para determinação da massa seca. Ao final do estudo, os vasos foram desmontados sobre uma peneira e os tapetes foram lavados, bem como o sistema radicular. Em seguida avaliou-se a espessura total do tapete com e sem aparas, comprimento de raiz e posteriormente determinou-se da massa seca deste material. Todos os experimentos foram instalados no delineamento experimental inteiramente casualizado, com quatro repetições. Os resultados foram submetidos à análise de variância pelo Teste F, e as médias dos tratamentos foram comparadas pelo teste de “t” a 5% de probabilidade, com auxílio do programa estatístico Sisvar. Todos os reguladores vegetais foram visualmente seletivos às espécies de grama. Os tratamentos com trinexapac-ethyl e prohexadione-cálcio reduziram o crescimento das três espécies de grama dependendo da dose e da época testada. Os tratamentos com piraclostrobina aplicada isolada ou em mistura dependendo da época, da dose e da espécie podem proporcionar uma melhor qualidade do tapete de grama. / The turfgrasses can be used in different environments for different purposes, and possess intrinsic properties such as species of grass used, the level of maintenance and the techniques adopted. The use of plant growth regulators within a proper handling, enables a higher efficiency is the maintenance or production grass sod quality. Thus, this study aimed to evaluate the effects of trinexapac-ethyl, pyraclostrobin associated or not with epoxiconazole and prohexadione-calcium as plant regulators on the growth and quality of species grasses Esmeralda (Zoysia japonica Steud.), São Carlos (Axonopus compressus (SW.) Beauv.) and Bermuda (Cynodon dactylon (L.)). In the first study, the doses and treatments (g a.i. ha-1 ) tested, both with and without reapplication were: trinexapac-ethyl of 113.0 to 226.0, pyraclostrobin + epoxiconazol of (66.5+25.0) to (113.0+50.0), pyraclostrobin of 100.0 to 200.0, in addition to a control for each species evaluated. In the second study, the doses and treatments (g a.i. ha-1 ) tested with two and three reapplication were prohexadione-calcium of 27.5 to 165.0, plus a control without application of growth regulator. In both studies, were performed visual injury evaluations using a scale of notes, in which "0" corresponded to any injury, demonstrated by plants and "100" the death of plants. Were also assessed: plant height, number of inflorescences, in addition to the collection of scrap to determine the dry mass. At the end of the period of conducting the study, the vessels were dismantled on a sieve and rugs were washed away, as well as the root system. Then the total thickness of the mat with and without chips, root length and subsequently was dry mass of this material. All experiments were installed in completely randomized experimental design with four replications. The results were submitted to analysis of variance F-test, and the averages of the treatments were compared by t test at 5% probability, with the aid of statistical program Sisvar. All plant growth regulators were visually selective to the grass species. The treatment with trinexapac-ethyl and prohexadione-calcium reduced the growth of three species of grass depending on dose and season tested. Treatments with pyraclostrobin applied alone or in combination depending on the season, the dose and the species can provide a better quality of the grass sod. / CNPq: 141423/2012-9
8

Manejo da floração de mangueiras no Semi-árido do nordeste brasileiro com inibidores da síntese de giberelinas

Mouco, Maria Aparecida do Carmo [UNESP] 07 November 2008 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:32:27Z (GMT). No. of bitstreams: 0 Previous issue date: 2008-11-07Bitstream added on 2014-06-13T20:04:01Z : No. of bitstreams: 1 mouco_mac_dr_botfca.pdf: 976151 bytes, checksum: 028a98e349191bffef5f2b0e8c7d42fa (MD5) / Outra / A mangicultura na região semi-árida destaca-se no cenário nacional não só pela expansão da área cultivada, volume de produção, altos rendimentos e qualidade do fruto produzido, mas também pela possibilidade de produção durante todo o ano devido às condições climáticas e às tecnologias para o manejo do crescimento vegetativo e da floração, com uso da irrigação, podas e utilização de reguladores vegetais. O paclobutrazol aplicado ao solo é utilizado no manejo da produção da mangueira na maioria dos pomares. Entretanto, há a necessidade de identificar outros reguladores vegetais que ofereçam a eficiência no manejo de produção das diferentes cultivares e que possam ser aplicados via foliar, de forma a minimizar os riscos de resíduo no solo e da aplicação de quantidades inadequadas ao longo dos anos. Assim, este trabalho teve como objetivo avaliar o efeito de reguladores vegetais aplicados via foliar quanto à eficiência no manejo da floração das cultivares Tommy Atkins e Kent, com maior precisão na recomendação da dose e menores riscos de contaminação da planta e do solo, permitindo o escalonamento da produção da mangueira. Os experimentos foram conduzidos na região do Vale do Rio São Francisco, em casa de vegetação, na Embrapa SemiÁrido e em condições de campo, nas Fazendas Frutavi e Andorinhas, localizadas no município de Petrolina, PE, entre outubro de 2005 e julho de 2008. Foram avaliados três reguladores vegetais aplicados via foliar: prohexadione-Ca, etil-trinexapac e cloreto de chlormequat, em duas doses, sendo estes comparados ao paclobutrazol aplicado ao solo, em delineamento de blocos ao acaso, com quatro repetições e duas plantas por parcela. Para a comparação do efeito dos tratamentos, registraram-se dados relativos à brotação vegetativa (percentagem e comprimento dos ramos), emissão de panículas (percentagem e comprimento),... / The mango crop within the semi-arid region stands out in the national scenario due to the expansion of the planted area, the production quantity, high yields and quality of the fruit produced, as well as to the possibility of all-year production due to climatic conditions and technologies that allow the management of plant growth and blossom, through irrigation, pruning and use of plant growth regulators. Paclobutrazol applied to the soil is used for the production management of mango in most of the orchards. However, it is necessary to identify other vegetal regulators that might be efficient for the production management of different cultivars and might be applied to the leaves, so as to minimize the risk of residues in the soil and inadequate application quantities over several years. Therefore, the present paper has the purpose to evaluate the effect of plant growth regulators that can be applied to the leaves, regarding their efficiency for the blossom management of the cultivars Tommy Atkins and Kent, allowing off season mango production with higher precision in dosage recommendation and lesser contamination risk for the plant and the soil. The experiments were carried out in the area of the São Francisco river valley, under green-house conditions at Embrapa Semi-Àrido, and under field conditions on the farms Frutavi and Andorinhas, both located in the municipality of Petrolina, Pernambuco state, from October 2005 to July 2008. Three plant growth regulators, sprayed to the leaves, were evaluated: prohexadione-Ca, trinexapac-ethyl and chlomequat cloride, applied in two dosages, and compared to paclobutrazol applied to the soil, using a randomized blocks design, with four replications and two plants per plot. In order to compare the effects of the treatment, data were recorded related to vegetative growth (percentage and length of the shoots), ...(Complete abstract, click electronic access below)
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Effect of Prohexadione-Calcium on Spearmint (Mentha spicata L.)

Meagy, Md J. 01 January 2009 (has links) (PDF)
Prohexadione-calcium (Pro-Ca), a plant growth regulator used primarily in fruit trees to suppress excessive vegetative growth and to inhibit disease incidence, is known to inhibit dioxygenase enzymes and to inhibit GA biosynthesis. It induces genes for polyphenols synthesis. The objective of this project was to determine if the bioregulator Pro-Ca would alter the yield of essential oil, secondary metabolites, and growth in spearmint. Spearmint shoot cuttings from the same mother plant were used in this study. The plants were treated with 0, 125, 250, 375, and 500 mg/L a.i. of Pro-Ca over four weeks, and growth responses were measured every week and at harvest. Compared with the untreated control plants, plant height, branch length, number of nodes, and fresh weight were decreased with increased concentration of Pro-Ca treatment, and total phenolics accumulation increased. Rosmarinic acid and total chlorophyll content were reduced relative to control after treatment. Treatment with increased concentration of Pro-Ca altered the accumulation of flavonoids compounds. Increased concentration of catechin and eriodictyol-7-glucoside, and decreased concentrations of procyanidin and luteolin occurred compared with the untreated plant. Modification of newly formed flavonoid synthesis could be used as a new potential strategy in plant protection.
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Manejo da floração de mangueiras no Semi-árido do nordeste brasileiro com inibidores da síntese de giberelinas /

Mouco, Maria Aparecida do Carmo, 1956- January 2008 (has links)
Orientador: Elizabdeth Orika Ono / Banca: João Domingos Rodrigues / Banca: Sarita Leonel / Banca: Regina Celi Cavestré Coneglian / Banca: Valtemir Gonçalves Ribeiro / Resumo: A mangicultura na região semi-árida destaca-se no cenário nacional não só pela expansão da área cultivada, volume de produção, altos rendimentos e qualidade do fruto produzido, mas também pela possibilidade de produção durante todo o ano devido às condições climáticas e às tecnologias para o manejo do crescimento vegetativo e da floração, com uso da irrigação, podas e utilização de reguladores vegetais. O paclobutrazol aplicado ao solo é utilizado no manejo da produção da mangueira na maioria dos pomares. Entretanto, há a necessidade de identificar outros reguladores vegetais que ofereçam a eficiência no manejo de produção das diferentes cultivares e que possam ser aplicados via foliar, de forma a minimizar os riscos de resíduo no solo e da aplicação de quantidades inadequadas ao longo dos anos. Assim, este trabalho teve como objetivo avaliar o efeito de reguladores vegetais aplicados via foliar quanto à eficiência no manejo da floração das cultivares Tommy Atkins e Kent, com maior precisão na recomendação da dose e menores riscos de contaminação da planta e do solo, permitindo o escalonamento da produção da mangueira. Os experimentos foram conduzidos na região do Vale do Rio São Francisco, em casa de vegetação, na Embrapa SemiÁrido e em condições de campo, nas Fazendas Frutavi e Andorinhas, localizadas no município de Petrolina, PE, entre outubro de 2005 e julho de 2008. Foram avaliados três reguladores vegetais aplicados via foliar: prohexadione-Ca, etil-trinexapac e cloreto de chlormequat, em duas doses, sendo estes comparados ao paclobutrazol aplicado ao solo, em delineamento de blocos ao acaso, com quatro repetições e duas plantas por parcela. Para a comparação do efeito dos tratamentos, registraram-se dados relativos à brotação vegetativa (percentagem e comprimento dos ramos), emissão de panículas (percentagem e comprimento),...(Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The mango crop within the semi-arid region stands out in the national scenario due to the expansion of the planted area, the production quantity, high yields and quality of the fruit produced, as well as to the possibility of all-year production due to climatic conditions and technologies that allow the management of plant growth and blossom, through irrigation, pruning and use of plant growth regulators. Paclobutrazol applied to the soil is used for the production management of mango in most of the orchards. However, it is necessary to identify other vegetal regulators that might be efficient for the production management of different cultivars and might be applied to the leaves, so as to minimize the risk of residues in the soil and inadequate application quantities over several years. Therefore, the present paper has the purpose to evaluate the effect of plant growth regulators that can be applied to the leaves, regarding their efficiency for the blossom management of the cultivars Tommy Atkins and Kent, allowing off season mango production with higher precision in dosage recommendation and lesser contamination risk for the plant and the soil. The experiments were carried out in the area of the São Francisco river valley, under green-house conditions at Embrapa Semi-Àrido, and under field conditions on the farms Frutavi and Andorinhas, both located in the municipality of Petrolina, Pernambuco state, from October 2005 to July 2008. Three plant growth regulators, sprayed to the leaves, were evaluated: prohexadione-Ca, trinexapac-ethyl and chlomequat cloride, applied in two dosages, and compared to paclobutrazol applied to the soil, using a randomized blocks design, with four replications and two plants per plot. In order to compare the effects of the treatment, data were recorded related to vegetative growth (percentage and length of the shoots), ...(Complete abstract, click electronic access below) / Doutor

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