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From Introduction: With the rapidly growing knowledge on trace elements and their influence on plant nutrition the need for accurate and rapid methods for their determination arose. The essential plant nutrients are usually divided into two groups. The major or macronutrient elements, necessary in comparatively large amounts, and the trace or micro-nutrient elements. In the case of plants, the first group includes Sulphur, Phosphorus, Potassium, Magnesium, Calcium and Nitrogen. The essential trace elements are Iron, manganese, Boron, Copper, Zinc, Molybdenum and Chlorine. Cobalt is essential for animal nutrition as a constituent of Vitamin B₁₂, but its essentiality for plants has not yet been proved. The latter group consists of metals which are catalysts in enzyme reactions and whose presence in the plant in minute amount determines whether the plant will be able to complete the vegetative or reproductive stage of its life cycle. Molybdenum may be quoted as an example of an essential trace element. It is generally recognised to be the catalyst responsible for the fixation of Nitrogen.

Resumo: Com intuito de avaliar a viabilidade do uso em ambiente protegido de água residuária via fertirrigação por capilaridade em mudas de Qualea sp. foi desenvolvido um estudo no viveiro do Departamento de Recursos Naturais/Ciências Florestais, Fazenda Experimental Lageado, pertencente à Faculdade de Ciências Agronômicas - FCA- da UNESP de Botucatu, Estado de São Paulo. Avaliou-se o desempenho das mudas de Qualea dichotoma (Mart.) Warm (pau terra da areia) e Qualea jundiahy Warm. (pau terra da mata), produzidas em tubetes de 53 cm³, usando 2 tipos de substrato, areia e comercial, irrigadas por capilaridade, com água potável e água residuária da Estação de Tratamento de Esgoto da Sabesp de Botucatu. O delineamento estatístico adotado foi inteiramente casualizado, com 4 parcelas de 20 plantas cada uma. Ao final de 90 dias foi avaliado, o diâmetro da base do colo (DC), a altura de parte aérea (HPA), a relação entre altura e o diâmetro (Rel: H/D), massas secas do sistema radicular (MSR), da parte aérea (MSA), total (MST), acúmulo de nutrientes (AN), porcentagem de acúmulo de nutrientes (% AN), qualidade do torrão (QT) e índice de Dickson (IQD). Os resultados indicaram que: para a sp dichotoma a água residuária possibilitou melhores resultados / Abstract: In order to evaluate the feasibility of using in na environment protected from wastewater by capillary fertigation on the growth of Qualea sp. a study was developed in the nursery of the Department of Natural Resources / Forestry Sciences, Experimental Farm Lageado, pertencte the Faculty of Agricultural Sciences - FCA UNESP Botucatu, São Paulo State. We'evaluated the performance of seedlings Qualea dichotoma (Mart.) Warm. (rolling land of sand) and what Qualea jundiahy Warm. (rolling land of woods), produced in tubes of 53 cm3, using two types of substrate: sand and commerccial irrigated with potable water by capillarity and wastewater from sewage treatment station of Botucatu Sabesp. The statistical desingn was completely randomized design with four plots of 20 plants each. At the end of 90 days was measured, the diameter of the base of the neck (DC), the height of the air (HPA), the relationship beetween height and diameter (Rel: H/D), root dry mass (MSR), shoot (MSA), total (MST), accumulation of nutrients (NA), percentage of nutrients (%AN), quality of the root ball (QT) and Dickson index (IQD). The results indicated that, for the wastewater sp dichotoma best possible results / Orientador: Hélio Grassi Filho / Coorientador: Magali Ribeiro da Silva / Banca: João Carlos Cury Saad / Banca: Jane Luisa Wadas Lopes / Mestre

The Christmas tree and greenery trade is a multi-million dollar industry in Atlantic Canada. Christmas trees grown in Nova Scotia are shipped internationally especially, to the United States. This thesis was set out to answer the over-arching hypothesis: pre- and post- harvest needle nutrient content influences post-harvest needle retention. Through a series of experiments it was shown that the pre-harvest needle P, Ca, Mg, Mn, Zn and B contents do not appear to be directly linked to post-harvest needle retention. Alternatively, the pre-harvest needle N, K, Cu and Fe contents significantly, but negatively influenced post-harvest needle retention. By maintaining needle N, K, Cu and Fe concentrations below 1.5 %, 0.55 %, 3.7 ppm and 35 ppm, respectively may extend needle retention in balsam fir. Xylem-fed nutrients negatively influenced needle retention. As well, foliar applications of calcium and zinc citrate did not promote needle retention at the concentrations used.

Several reports appear in the literature linking low temperature damage in plants with boron (B) deficiency and alleviation of low temperature injury with B application has been reported in some crops and trees. These results imply that low temperature might increase plant B requirements, beside the reduction of B uptake by plant roots, or that low B tissues might be more sensitive to cold temperature damage than B adequate tissues. In controlled experiments, it has been shown that low root zone temperature (RZT) induces B deficiency in cassava, a tropical root crop. Apart from this, there are few definitive detailed investigations on low temperature effects on B nutrition of plants, including temperate species which are more tolerant of low temperature. Winter oilseed rape (Brassica napus L.), a crop sensitive to low B supply, is a major crop in the middle and lower Yangtse river basin, China, where low B soils are widespread. Appearance of B deficiency in oilseed rape often coincides with cold weather during its winter and spring growth. However, the incidence and severity of B deficiency of oilseed rape plants and the efficacy of B fertilization varies from year to year and location to location in ways that are not explained simply by differences in cultivar, agronomy or soil B levels. Low temperature is probably one of the important environmental factors influencing growth and yield of oilseed rape in relation to B nutrition. Therefore,the objective of the studies in this thesis was to investigate mechanisms of low temperature effects on B nutrition of plants with emphasis on oilseed rape. Field and glasshouse experiments were carried out and the physiological basis of plant response to B at different air and root temperatures is discussed. A field experiment with oilseed rape cv. Zheyouyou 2 was carried out on a red soil (Hapludult, US Soil Taxonomy) with low B availability in Zhejiang province, China. Canopy covers made from transparent plastic sheets, which increased night temperatures by up to 1.5 oC around shoots for 15 days in early February, strongly increased shoot dry weight at all levels of B supply. Furthermore, covering plants increased shoot dry weight of B deficient plants without increasing their leaf B concentration. This suggests that internal B requirements were decreased by canopy covering, possibly due to higher temperatures within the canopy. Experiments conducted to investigate the effect of RZT (10 and 20ƒn oC) on oilseed rape cv. Hyola 42 response to B in solution culture, in summer and winter, showed that regardless of canopy conditions, low RZT (10 oC) promoted the distribution of shoot B towards the actively growing leaves, especially when B supply was low. At low B supply, B deficiency symptoms appeared later at 10 oC than 20 oC RZT and B concentrations in the youngest fully opened leaves (YOL) were higher in plants grown at RZT of 10 oC than that at 20 oC. Growth of plant dry weight (DW) was not affected by RZT in the summer but was greatly reduced at 10 oC than 20 oC in winter. In B adequate plants, shoot to root ratio (S/R ratio) was not affected by RZT regardless of canopy conditions. By contrast, S/R ratio was smaller in low B plants at 10 oC than 20 oC. In addition, low RZT delayed occurrence of plant B deficiency symptoms regardless of plants¡¦ pre-treatment RZT (either 10 or 20 oC). These results appeared to contradict the response to low RZT found in previous studies with cassava. In a subsequent experiment, low RZT of 5 oC not only greatly reduced plant DW production of oilseed rape, but also accentuated plant B deficiency. Partitioning of B into the young growing shoots was also depressed and a significant decrease of B concentration in the youngest shoot parts was caused by 5 oC RZT in comparison with that at the control RZT (10 oC). Similar results were also observed in sunflower (Helianthus annuus L. cv. Hysun 25). But B deficiency symptoms in sunflower were induced by RZT as high as 12 oC, when plants were supplied with 0.25 £gM B, whilst these plants were free from B deficiency at warmer RZT (17 - 27 oC). Higher external B concentrations were required at such RZT (Chilling temperature) for plant growth free from B deficiency. Therefore, there is a RZT threshold below which an increased response to B is expected in plants of oilseed rape and sunflower. And in the range of chilling RZT, the external B requirement for shoot growth increased with lower RZT. The threshold RZT was considerably higher in the chilling-sensitive plant species, sunflower, than in oilseed rape, a chilling-resistant plant species. At chilling RZT, leaf functioning was impaired by low B supply as measured by potassium (K) leakage from the youngest mature leaf blade (YML) of sunflower, whereas it was much less directly affected by RZT, and there was no effect of RZT on B- adequate plants. By contrast to leaves, root function was impaired more by chilling RZT than low B. Despite their different threshold RZT, in both oilseed rape and sunflower, the rates of B uptake (BUR) and B translocation from root to shoot (BTR) were dramatically depressed by chilling RZT especially at low B supply (0.2 £gM B): being only 30% of those at the control (5 oC vs 10 oC RZT) in oilseed rape and 33% (10 oC vs 20 oC RZT) in sunflower, respectively. By contrast, there was little or no difference over a range of warmer RZT (10 - 20 oC for oilseed rape, and 20 ¡V 27 oC for sunflower). It is predicted that higher rates of B application will be required for plant growth when soil temperature is below a critical threshold, which is between 5 and 10 oC for oilseed rape, and about 17 oC for sunflower, respectively. Below the threshold RZT plant B deficiency was induced and accentuated due to impairment of B translocation into growing shoot parts besides the decrease of B uptake rate and B transport rate and greater shoot to root ratio. In comparison with RZT, little is known about causal mechanisms linking cold air temperature and B nutrition. Experiments in this thesis showed not only B transport to the shoot was strongly reduced by low night air temperature during a 6 day period (11.719.4 vs 15.5 ¡V 23.5 oC), but also that an overnight chilling (at 0 oC) could cause more severe injury to low B than adequate B leaves of oilseed rape plants, expressed by higher solute leakage, in comparison with control (at 10 oC). Moreover, after chilling treatment, solute leakage from low B leaves was increased by exposure to light, which suggests that low temperature injury to leaves in low B plants after a freezing night in the field is at least partly a consequence of light induced damage of leaves. In summary, at chilling temperature, B uptake, transport and partitioning into growing shoots are strongly impaired, and B use efficiency in the growing tissues might be reduced as well. Low temperature contributes to plant B deficiency also by increasing S/R ratio, so that shoot B demand is not satisfied by available B. Furthermore, low air temperature might increase the internal B requirement for shoot growth. To further understand mechanisms of low temperature, especially the air temperature, effects on plant responses to B, more research is needed, such as the relationship between low temperature and B incorporation into cell walls which may play an important role in leaf tolerance to chilling temperature.

Made available in DSpace on 2014-06-11T19:26:47Z (GMT). No. of bitstreams: 0 Previous issue date: 2011-08-30Bitstream added on 2014-06-13T19:55:04Z : No. of bitstreams: 1 miggiolaro_ja_me_botfca.pdf: 752380 bytes, checksum: 8f9be39cd3f787d2b680f26f63338e96 (MD5) / Universidade Estadual Paulista (UNESP) / Com intuito de avaliar a viabilidade do uso em ambiente protegido de água residuária via fertirrigação por capilaridade em mudas de Qualea sp. foi desenvolvido um estudo no viveiro do Departamento de Recursos Naturais/Ciências Florestais, Fazenda Experimental Lageado, pertencente à Faculdade de Ciências Agronômicas – FCA- da UNESP de Botucatu, Estado de São Paulo. Avaliou-se o desempenho das mudas de Qualea dichotoma (Mart.) Warm (pau terra da areia) e Qualea jundiahy Warm. (pau terra da mata), produzidas em tubetes de 53 cm³, usando 2 tipos de substrato, areia e comercial, irrigadas por capilaridade, com água potável e água residuária da Estação de Tratamento de Esgoto da Sabesp de Botucatu. O delineamento estatístico adotado foi inteiramente casualizado, com 4 parcelas de 20 plantas cada uma. Ao final de 90 dias foi avaliado, o diâmetro da base do colo (DC), a altura de parte aérea (HPA), a relação entre altura e o diâmetro (Rel: H/D), massas secas do sistema radicular (MSR), da parte aérea (MSA), total (MST), acúmulo de nutrientes (AN), porcentagem de acúmulo de nutrientes (% AN), qualidade do torrão (QT) e índice de Dickson (IQD). Os resultados indicaram que: para a sp dichotoma a água residuária possibilitou melhores resultados / In order to evaluate the feasibility of using in na environment protected from wastewater by capillary fertigation on the growth of Qualea sp. a study was developed in the nursery of the Department of Natural Resources / Forestry Sciences, Experimental Farm Lageado, pertencte the Faculty of Agricultural Sciences – FCA UNESP Botucatu, São Paulo State. We`evaluated the performance of seedlings Qualea dichotoma (Mart.) Warm. (rolling land of sand) and what Qualea jundiahy Warm. (rolling land of woods), produced in tubes of 53 cm3, using two types of substrate: sand and commerccial irrigated with potable water by capillarity and wastewater from sewage treatment station of Botucatu Sabesp. The statistical desingn was completely randomized design with four plots of 20 plants each. At the end of 90 days was measured, the diameter of the base of the neck (DC), the height of the air (HPA), the relationship beetween height and diameter (Rel: H/D), root dry mass (MSR), shoot (MSA), total (MST), accumulation of nutrients (NA), percentage of nutrients (%AN), quality of the root ball (QT) and Dickson index (IQD). The results indicated that, for the wastewater sp dichotoma best possible results

Iron is abundant in most agricultural systems, however it is also one of the three most limiting nutrients for crop growth. This can be attributed to iron’s low solubility in aerobic and alkaline conditions, rendering it non-bioavailable for plant uptake. With around 1/3 of the world arable land presenting conditions that limit iron solubility, deciphering the plant machinery behind iron uptake and identifying microbial benefits to iron deficiency are of major interest. In this work, 33 endophytic bacterial isolates previously isolated from three regions in Jordan were tested for iron stress alleviation of Arabidopsis plants with the goal of identifying novel interaction mechanisms. On media with a low concentration of bioavailable iron, 11 isolates were found to be beneficial, while 15 isolates behaved in a pathogenic manner, reducing plant growth in both control as well as limited iron conditions. Beneficial isolates were then tested in plant assays with non-bioavailable iron, we concluded that our strains are also beneficial in these conditions. To further characterize the interaction between the beneficial strains and Arabidopsis plants, gene expression was assessed for plants colonized with select strains. The highest expression of iron-deficiency response genes was at day 6. The increase in expression was also met with an increase in colonization of plants at day 6. Mutant studies revealed that the beneficial effect by the bacterial isolates is dependent on the coumarin pathway, with mutants in FERULOYL-COA 6-HYDROXYLASE 1, f6’h1, showing a drastic decrease in fresh weight compared to wild type counterparts. We also discovered the phytohormone abscisic acid as an important contributor to iron stress alleviation by the beneficial isolates. Colonization assays as well as additional mutant studies will be necessary to further assess the effect of f6’h1 mutants on plant-microbe interaction as well as ABA’s role in plants under iron deficient conditions.

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O objetivo foi avaliar a influência de fertilizantes nitrogenados e do fornecimento de enxofre sobre a composição químico-bromatológica e algumas características agronômicas da cultura da cana-de-açúcar, bem como as perdas de N no sistema solo x Planta. O estudo foi conduzido no município de Araras/SP, numa área do Grupo Usina São João, durante dois anos de avaliação. A variedade utilizada foi a SP80-1816. As avaliações iniciaram-se após o primeiro e segundo cortes, sem queima prévia, e mecanicamente. O delineamento experimental foi em blocos inteiramente casualizados, com dez tratamentos (T1: Testemunha+Gesso (-N+S); T2: Testemunha absoluta (-N-S); T3: Uréia 45%N; T4: Uréia+Gesso; T5: Uréia+Sulfato de Amônio (SA) - 21%N/24%S - (33:00:00+12%S); T6: Nitrato de Amônio (NA) - 30%N; T7: Nitrato de Amônio (NA) - 30%N + Gesso; T8: NA + Sulfato de Amônio - 21%N/24%S - (27,8:00:00+6%S); T9: SA; T10: FASN (SA e NA - 26%N/14%S)) e quatro repetições, formando 40 parcelas experimentais, para o fornecimento de 100 kg N/ha. Cada parcela experimental constou de sete linhas de cana-de-açúcar espaçadas de 1,4 metro e 13 metros de comprimento, perfazendo área total de 127,4 m2, considerando-se como úteis as cinco linhas centrais, descontando-se as duas linhas laterais e 1,5 metro de cada extremidade da parcela, como bordadura. As avaliações das perdas de N-NH3 por volatilização foram efetuadas após a colheita, no momento da adubação de cobertura. As maiores perdas acumuladas de N-NH3 provieram da aplicação de Uréia seguida pelos tratamentos Uréia+Gesso e Uréia+SA em ambas as socas da cana-de-açúcar. Ocorreram, na segunda soca aumento nas perdas, que foram maiores logo após a aplicação sendo os níveis mínimos aos 9 e 11 dias para 1ª e 2ª soca respectivamente. As fontes nitrogenadas aumentaram os teores de N foliar na cana-de-açúcar. As fontes de enxofre beneficiaram os teores do elemento no solo, considerando-se a camada de 0-20 cm. As fontes de nitrogênio e enxofre propiciaram redução da porcentagem de fibras de acordo com os resultados da composição químico-bromatológica da cana-de-açúcar. Para a produtividade da cana-de-açúcar acumulada em duas safras consecutivas, o FASN foi a fonte que proporcionou melhor resposta, seguido do SA e NA. / The present studys objective was to evaluate the nitrogen fertilizing efficiency and the sulphur supplying over the chemical bromatological composition of some sugar cane agronomical characteristics as well as the nitrogen losses in the soil x plant system. The study was performed in Araras/SP county, in the Sao Joao Usine Group area, in a two year evaluation period. The used variety was the SP80-1816. The evaluation started after the first and second harvest, without previous burning, and mechanically. The experimental design was based on the random blocks standard, with ten treatments (T1: Control+Gypsum (-N+S); T2: Control (-N-S); T3: Urea 45%N; T4: Urea+Gypsum; T5: Urea+Ammonium Sulphate (SA) - 21%N/24%S - (33:00:00+12%S); T6: Ammonium Nitrate (NA) - 30%N; T7: Ammonium Nitrate (NA) - 30%N + Gypsum; T8: NA + Ammonium Sulphate - 21%N/24%S - (27,8:00:00+6%S); T9: SA; T10: FASN (SA e NA - 26%N/14%S)) and four repetitions, totalizing 40 experimental parcels, for 100Kg N/ha. Each experimental parcel was composed by 7 sugar cane lines spaced in 1,4m and 13 m long, distributed in a 127,4 m2 area, considering the five central line as useful, discounting two lateral lines and 1,5 m from each parcels extremity, as border segment. The N-NH3 volatization loss evaluation was effectuated after harvest, during cover fertilization. The highest accumulated N-NH3 losses were generated from Urea application followed by Urea+Gypsum and Urea+SA in both sugar canes ratoons. It was observed, in the second ratoon, a loss increasing, that was higher after the application, where the minimum rate were in the 9th and 11th days for the 1st and 2nd ratoon, respectively. The nitrogen sources increased the N leaf rate in sugar cane. The sulfur sources beneficiated this specific element rate in the soil, considering the 0-20 cm stage. The nitrogen and sulfur sources generated fiber percentage reduction, according to the chemical bromatological composition results. For accumulated sugar cane productivity in two consecutive crops, the FASN was the source that generated the best response, followed by SA and NA.