Seed tubers conditioned to 0, 200 or 400 day-degrees above 4t were grown in land infested with Q. pallida. Plants from 400 day-degree seed emerged earlier, had larger canopies and greater dry weights early in the growing season than plants from 0 day-degree seed. However, physiological ageing reduced peak percentage ground cover and advanced crop senescence so that similar quantities of solar radiation were intercepted over the whole growth period. Overall, total and ware yields were not affected much by seed tuber physiological age. The partially resistant cultivars tested were more tolerant than the non resistant cultivars but tolerance was not usually affected by physiological age of seed tubers. The effects of nematicide treatment, initial Q. pallida population density, cultivar maturity class, cultivar resistance status and planting date on nematode multiplication, plant growth and tolerance of attack by Q. pallida are discussed. Using data from a variable temperature water bath experiment, probability and regression analysis estimated mean basal temperatures for the development of Q. pallida and Q. rostochiensis at 2.5 and S.rCi least variance analysis estimates were 3.5 and 4.rC respectively. Approximately 200 day-degrees above 3.5 and 4.rC were required from the inoculation of JJ2 of Q. pallida and G. rostochiensis to the peak numbers of JJ5 found in potato roots. From a range of chemicals tested for their ability to release antigen from Q. pallida cysts, sodium hypochlorite was found to be the most effective. Released antigen was detected using polyclonal antisera and monoclonal antibodies in an ELISA test. The potential for the development of an ELISA based diagnosis test for PCN using species-specific antibodies is discussed.

Made available in DSpace on 2015-03-26T13:39:31Z (GMT). No. of bitstreams: 1 texto completo.pdf: 315914 bytes, checksum: 05016c334bd87946fdf8644762c02d17 (MD5) Previous issue date: 2009-05-29 / Conselho Nacional de Desenvolvimento Científico e Tecnológico / New propagation techniques have been proposed for production of the basic potato-seed (Solanum tuberosum L.), such as the propagation by sprout, hydroponics and planting in pots containing substratum. Those new techniques represent an important progress in the potato productive process. In the available literature, there are few studies relating the effect of the nitrogen doses in solution and in substratum upon the yield of the basic potato-seed by the using the sprout as propagation material. This dissertation was carried out to determine the optimum nitrogen dose for the yield of minitubercules of the basic potato-seed in two production systems, by using the sprout of the Asterix cv. as propagation material. The planting in vase with the commercial substratum Plantmax® and fibrocement tile were those systems. Each system corresponded to one experiment. The treatments in pot were five nitrogen doses (0; 45; 90; 180 and 360 mg dm-3), whereas in the hydroponic system were four nitrogen doses (45; 90; 180 and 270 mg L-1). In the pot system, 10% from each nitrogen dose were applied daily at pre-planting and the remainder via irrigation water for 30 days. In the hydroponic system, the nitrogen doses were supplied since the transplanting of the seedlings, and the nitrogen sources were the ammonium nitrate (10%) and calcium nitrate. Both experiments were set up in greenhouse. In both experiments, the N doses positively affected both physiological and nitrogenous indexes in either fourth leaf and the old one (length, width, leaf area, leaflet number, both fresh and dry, content and concentration of Norg and N-NO-3 respectively in the dry matter, and the SPAD index). The nitrogen doses also positively affected both number and matter of the tubercles. In the pot system, the highest number (5.44 tubercules/plant) and the maximum matter of tubercules (243.5 g/plant) were obtained, when using the N doses 360 and 332.9 mg dm-3, respectively. Yet in pot, the critical index SPAD found for the fourth leaf was 38.8, as QF being more sensible to the effect of the N dose than the oldest leaf. In the hydroponic system, the productivity values by plant were 14.1 tubercules and 68.4g at the N doses 188.9 and 270 mg L-1, respectively. The SPAD index found for the fourth leaf was 38.4. In both systems, the number and matter of the tubercules by plant were not optimized by the same nitrogen dose. / Novas técnicas de propagação vêm sendo propostas para produção de tubérculo-semente básica de batata (Solanum tuberosum L.) dentre as quais a propagação por broto, hidroponia e plantio em vasos contendo substrato. Estas novas técnicas representam avanço importante no processo produtivo da batata. São raros os estudos relacionando doses de nitrogênio em solução e no substrato sobre a produção de batata-semente utilizando-se broto como material de propagação. O objetivo da dissertação foi determinar a dose ótima de nitrogênio para a produção de minitubérculos de batata-semente básica em dois sistemas de produção utilizando broto do cultivar Asterix como material de propagação. Os dois sistemas foram plantio em vaso com substrato comercial Plantmax® e telha de fibrocimento. Cada sistema foi um experimento. Os tratamentos em vaso foram 5 doses de nitrogênio (0; 45; 90; 180 e 360 mg dm-3) e no sistema hidropônico os tratamentos foram 4 doses de nitrogênio (45; 90; 180 e 270 mg L-1). No sistema em vaso, 10% de cada dose de nitrogênio foi aplicada em pré-plantio e o restante via água de irrigação, diariamente por 30 dias. As doses de nitrogênio no sistema hidropônico foram fornecidas desde o transplantio das mudas, e as fontes de nitrogênio foram o nitrato de amônio (10%) e nitrato de cálcio. Ambos os experimentos foram instalados em casa de vegetação. Em ambos os experimentos, as doses de N influenciaram positivamente os índices fisiológicos e nitrogenados na quarta folha e na folha velha (comprimento, largura, área foliar, número de folíolos, massa fresca e seca, teor e conteúdo de Norg e N-NO3 - na matéria seca e índice SPAD. Da mesma forma doses de N influenciaram positivamente número e massa de tubérculos colhidos. No sistema de vaso, o maior número (5,44 tubérculos/planta) e a máxima massa de tubérculos (243,5 g/planta) foram obtidos com as doses de N de 360 e 332,9 mg dm-3, respectivamente. Ainda em vaso, o índice crítico SPAD encontrado para quarta folha foi 38,8, sendo a QF mais sensível ao efeito da dose de N do que a folha mais velha. No sistema hidropônico, os valores de produtividade por planta foram de 14,1 tubérculos e de 68,4 g com as doses de N de 188,9 e 270 mg L-1, respectivamente. O índice SPAD encontrado para quarta folha foi 38,4. Nos dois sistemas, número e massa de tubérculos por planta não são otimizados pela mesma dose de nitrogênio.

Orientadores Sylvio Luis Honório, Claudio Luiz Messias / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia Agrícola / Made available in DSpace on 2018-08-27T23:01:54Z (GMT). No. of bitstreams: 1 Rocha_ArturBatistadeOliveira_D.pdf: 1714662 bytes, checksum: 577fdeb54b226ba61587e77781ac70cf (MD5) Previous issue date: 2015 / Resumo: O cultivo da batateira (Solanum tuberosum L.) apresenta problemas fitossanitários decorrentes do ataque de pragas e doenças, o que acarreta altos cultos de produção. As principais doenças pós-colheita em batata-semente são: podridão seca (agente causal: Fusarium solani), rhizoctoniose (agente causal: Rhizoctonia solani) e podridão mole (agente causal: Pectobacterium carotovorum subsp. carotovorum). Os principais glicoalcaloides presentes na batata são a ?-chaconina e ?-solanina, os quais possuem propriedades antimicrobianas e podem ser estimulados por diversos fatores, com destaque para a luz. O objetivo desta pesquisa foi investigar a aplicação da radiação ultravioleta UV-C e da luz fluorescente no controle dos patógenos Fusarium solani, Rhizoctonia solani e Pectobacterium carotovorum subsp. carotovorum nas cultivares Ágata, Atlantic e Monalisa de batata-semente após a colheita. A pesquisa foi realizada em duas etapas: (I) avaliou-se in vitro o efeito da radiação UV-C no desenvolvimento das colônias de F. solani e de R. solani e na germinação dos conídios de F. solani. In vivo avaliou-se o efeito da radiação UV-C e da luz fluorescente na severidade e na incidência de podridão seca e de rhizoctoniose na brotação, na perda de massa e no teor de sólidos solúveis em batata-semente 'Agata' e 'Atlantic'; (II): avaliou-se in vitro o efeito da radiação UV-C no desenvolvimento das colônias de P. carotovorum subsp. carotovorum. In vivo avaliou-se o efeito da radiação UV-C e da luz fluorescente na severidade e na incidência da podridão mole, na concentração de ?-chaconina e de ?-solanina, na brotação, na perda de massa e no teor de sólidos solúveis em batata-semente 'Agata' e 'Monalisa'. A exposição de F. solani e R. solani a uma densidade de energia de 105,6 kJ.m-2 de radiação UV-C diminui o desenvolvimento das colônias desses fungos para estudos in vitro. Para a germinação de conídios de F. solani foi exposta a uma densidade de energia de 52,8 kJ.m-2 de radiação UV-C. Além disso, a luz fluorescente foi mais eficaz do que a radiação UV-C para o controle da podridão seca e da rhizoctoniose, sem afetar a brotação. A exposição de P. carotovorum subsp. carotovorum na densidade de energia de 34,5 kJ.m-2 de radiação UV-C inibiu o desenvolvimento das colônias para estudos in vitro. A luz fluorescente foi mais eficaz do que a radiação UV-C para controle da podridão mole em tubérculos de batata, assim como, estimulou a síntese de glicoalcaloides. O controle da podridão mole em tubérculos de batata está relacionado a maior concentração de ?-chaconina e ?-solanina, especialmente na periderme. Os teores de ?-chaconina (11,6 a 26,0 mg.kg-1P.F.) e ?-solanina (11,4 a 25,1 mg.kg-1P.F.) mostraram-se eficazes para o controle da podridão mole. Além disso, a brotação não foi afetada de forma adversa / Abstract: The cultivation of potato (Solanum tuberosum L.) in the tropics suffers the attack of pests and diseases, burdening the cost of production. The main postharvest diseases in potato seeds are the dry rot (pathogen: Fusarium solani), black scab (pathogen: Rhizoctonia solani) and wet rot (pathogen: Pectobacterium carotovorum subsp. carotovorum. The efficiency of UV-C against a wide variety of microorganisms has been reported and there is interest in applying for seed disinfection. Potato plants contain glycoalkaloids being ?-chaconine and ?-solanine the main ones. The accumulation of these glycoalkaloids can be stimulated by several factors, especially light, having them important antimicrobial properties. The aim of this research was to evaluate the the postharvest application of ultraviolet (UV-C) radiation and the fluorescent light to control the pathogens: F. solani, R. solani, and P. carotovorum subsp. carotovorum on 'Agata', 'Atlantic', and 'Monalisa' potato seeds. The research was conducted in two stages: (I) the evaluation in vitro of the effect of UV-C radiation on the growth of F. solani and R. solani colonies and F. solani conidias germination and the in vivo effect of UV-C radiation and fluorescent light on dry rot and black scab severity and incidence, mass loss and soluble solids content on 'Agata' and 'Atlantic' and (II) the evaluation in vitro of the effect of UV-C radiation on P. carotovorum subsp. carotovorum colonies and was reported in vivo the effect of UV-C radiation and the fluorescent light on the severity and incidence of wet rot, ?-chaconine and ?-solanine, concentration, tuber sprouting, weight loss and soluble solids on 'Agata' and 'Monalisa'. Exposure of R. solani and F. solani at an energy density of 105,6 kJ.m-2 of UV-C radiation decreases the development of fungi colonies in vitro. Energy density of 52,8 kJ.m-2 inhibited the F. solani conidias germination. Moreover the fluorescent light was more effective than UV-C radiation to control dry root and black scab, without affecting the sprouting. The in vivo experiments showed that treated and untreated. UV-C tubers stored under fluorescent light were more effective to control soft rot than the UV-C treated tubers and stored under darkness. Control tubers under fluorescent light, UV-C treated under darkness, and UV-C treated under fluorescent light showed an increased concentration of ?-chaconine (11,6 to 26,0 mg.kg-1F.W.) and ?-solanine (11,4 a 25,1 mg.kg-1F.W.) for both cultivars / Doutorado / Tecnologia Pós-Colheita / Doutor em Engenharia Agrícola

The potential benefits of plant genetic engineering for disease and pest resistance have been widely acknowledged in many studies, and although genetically modified crops are still encountering public wariness, these benefits warrant continued exploration. Because of its intrinsic economic benefits, the development of true potato seed (TPS) cropping systems has been instituted in many regions of the world. The incorporation of transgenic resistance could further the economic gain of farmers who are seeking ways to sustain their livelihood in the most efficient way possible. It is, however, largely unresearched how sexual hybridization of a transgenic crop would affect the behavior of a transgene in the resultant progeny. In the initial part of this study, transgenic lines were developed with a Cry3Aa transgene. These plants were then used in 4x-4x reciprocal crosses and 4x-2x hybridization schemes to determine the stability of the transgene after sexual hybridization. There was no observed parent of origin effect on transgene expression; however, a highly significant, non-mendelian inheritance of the Cry3Aa transgene was seen in the maternally inherited transgene of one set of progeny from a reciprocal cross. Additional transgenic lines of potato were developed with a PVY-O coat protein transgene. These plants were challenged with PVY-O and monitored for symptoms visually and for virus serologically. One transgenic line exhibited complete resistance to PVY-O while two others showed a delay in symptom occurrence. Further examination of the expression levels of the PVY-O coat protein transgene will be necessary to determine the type and usefulness of the observed resistance. / Master of Science

Potato (Solanum tuberosum L.) varieties Atlantic and Granola are widely grown in Indonesia. The optimal method of cultivation in the tropics, due to the susceptibility of cut seed for disease, is by small (20 to 55 g) whole seed potatoes. However, the variety Atlantic produces mostly large tubers, which are not suitable for planting as whole seeds. Although Granola produces a reasonable proportion of small tubers it still produces a few in the larger size grades and there is no fresh market in Western Australia for the larger tubers for this variety. The aim of this study was to develop methods to be used in Western Australia that improve the yield of small seed potatoes for export to Indonesia. The influence of seed-potato storage duration (at 4°C) on subsequent stem growth was assessed after 30 days growth in a glasshouse (22°C/18°C, day⁄night). Seed potato storage for 22-28 (Atlantic) and 24-30 (Granola) weeks resulted in development of higher numbers of stems. A series of field experiment were designed to increase yield of small tubers. Apical sprout removal in Granola, but not Atlantic, increased the number of stems (by 27%), yield of 20-55 g potato (by 32%) and total yield (by 17%). Application of herbicide (paraquat + diquat) at low concentration during early tuber initiation decreased total yield in Atlantic (by 14%) and Granola (by 16%). Treating whole seed potatoes with carvone vapor two weeks before planting had no influence on stem or tuber number in both Atlantic and Granola but in Atlantic only, the total yield was reduced by 12%. Spraying plants with paclobutrazol during early tuber initiation inconsistently influenced tuber number and yield between the two varieties and two experiments. The influence of gibberellic acid (GA3) on stem number, total tuber number, yield of 20-55 g tubers and total yield was investigated by dipping seed pieces in a GA3 solution (20 mg⁄L) two days prior to planting. In Atlantic, GA3 treatment increased stem number (by 147%), total tuber number (by 75%) and yield of 20-55 g tubers (by 330%) without influencing total yield. In Granola, GA3 treatment increased stem number (by 50%), total tuber number (by 15%), yield of 20-55 g tubers (by 21%) and total yield (by 10%) The influence of gibberellic acid application (20 mg⁄L) to seed pieces before planting increased the number of small tubers through increased stem number. The shift toward a greater proportion of small tubers, without reducing total yield, had a greater influence in Atlantic than that in Granola. Treatment of GA3 and paclobutrazol together decreased total yield compared to that of GA3 alone