Sugarcane extracts large amounts of nutrients from the soil and accumulates them in the plant due to its large mass production. Thus, agricultural practices ensuring adequate supply of nutrients to the crop must be adopted to obtain high crop yields in the cane plant cycle and small decreases in the subsequent cycles. In this chapter, the following items will be addressed and discussed: soil sampling, soil fertility evaluation, liming, plastering, cane plant chemical fertilization, sprout chemical fertilization, sugarcane nutritional status evaluation, organic fertilization, use of cultural remains and residues from sugar and alcohol industry, use of humic substances, fertilization, and quality of the sugarcane broth.

Additional information is available at the end of the chapter http://dx.doi.org/10.5772/54223. Introduction "biotic stress limits crop productivity [ ], and plays a major role in determining the distribution of plant species across different types of environments. "biotic stress and its effects on plants in both natural and agricultural settings is a topic that is receiving increasing attention because of the potential impacts of climate change on rainfall patterns and temperature extremes, salinization of agricultural lands by irrigation, and the overall need to maintain or increase agricultural productivity on marginal lands. In the field, a plant may experience several distinct abiotic stresses either concurrently or at different times through the growing season [ ].In reference [ ] are showed some common examples of the abiotic stresses a plant may encounter which include a decreased availability of water, extremes of temperature including freezing, decreased availability of essential nutrients from the soil or conversely the buildup of toxic ions during salt stress , excess light especially when photosynthesis is restricted or increased hardness of the soil that restricts root growth.In the face of a global scarcity of water resources and the increased salinization of soil and water, abiotic stress is already a major limiting factor in plant growth and will soon become even more severe as desertification covers more and more of the world's terrestrial area. Plants are often subjected to periods of soil and atmospheric water deficits during their life cycle. Moreover, the faster-than-predicted change in global climate [ ] and the different available scenarios for climate change suggest an increase in aridity for the semiarid regions of the globe. Together with overpopulation, this will lead to an overexploitation of water resources for agriculture purposes and increased constraints on plant growth and survival aid, therefore, on realizing crop yield potential [ ]. Thus, if a single abiotic stress is to be identified as the most common in limiting the growth of crops worldwide, it most probably is low water supply [ ].Like the water stress, salinity is one of the major severe abiotic factors affecting crop growth and productivity [ ]. Salt s negative effects on plant growth have initially been associated with the osmotic stress component caused by decreases in soil water potential and, consequently, restriction of water uptake by roots.The literature shows that drought and salinity are already widespread in many regions. Therefore, in reference [ ] the authors have presented that in world where population growth exceeds food supply, agricultural and plant biotechnologies aimed at overcoming severe environmental stresses need to be fully implemented. . . Plant stress definitionsThe term stress is most often used subjectively and with various meanings. The physiological definition and appropriate term for stress are referenced as responses to different situations. The flexibility of normal metabolism allows the...

-Salt and water stress during germination affect the emergence of seedlings in the field and, consequently, the stand of the plants and crop growth. Two experiments were conducted to evaluate the effects of water and salt stress on germination and vigor of seeds of two sorghum [Sorghum bicolor (L.) Moench] genotypes. The seeding was done inside "Gerbox" boxes, on two sheets of "germitest" paper dampened with distilled water (control) or with solutions of polyethylene glycol 6000 to provide the water potentials of -0.2, -0.4 and -0.8 MPa, or with NaCl at 75, 150 and 300 mM, respectively. The seed germination and vigor were evaluated by the first germination count (FGC), germination test (Gt), germination speed index (GSi) and germination average time (GAt). in both studies a randomized complete design in a 2 x 4 factorial arrangement was used, totaling eight treatments, with four replications of 50 seeds each. The CSF 18 genotype germination was affected only at the highest level of salinity (300 mM) with an increase in the GAT and reduction in the FGC, GSI and GT variables. The CSF 20 genotype showed similar performance, except for the GSI and GAT variables, which were affected by NaCl at the 150 mM concentration. The CSF 18 genotype had greater tolerance to water and salt stress during the germination phase than CSF 20.Index terms: Sorghum bicolor, physiology quality, osmotic stress, salinity. rESUMo -Condições de estresse hídrico e salino durante a fase de germinação afetam a emergência das plântulas no campo e, consequentemente, o estande das plantas e o desenvolvimento vegetativo das culturas. Através de dois experimentos objetivou-se avaliar os efeitos dos estresses hídrico e salino, na germinação e vigor de sementes de dois genótipos de sorgo forrageiro [Sorghum bicolor (L.) Moench]. A semeadura foi realizada no interior de caixas "Gerbox", sobre duas folhas de papel "germitest" umedecidas com água destilada (controle) ou com soluções de polietileno glicol 6000, de modo a fornecer os potenciais hídricos de -0,2, -0,4 e -0,8 MPa, ou com NaCl a 75, 150 e 300 mM, respectivamente. A germinação e o vigor das sementes foram avaliados através da primeira contagem (PCG), teste padrão (tG), índice de velocidade (ivG) e tempo médio de germinação (tMG). Utilizouse o delineamento experimental inteiramente casualizado em esquema fatorial (2x4), totalizando oito tratamentos, com quatro repetições de 50 sementes cada, em ambos os ensaios. o genótipo CSF 18 teve a germinação afetada somente no maior nível de salinidade (300 mM), observando-se aumento no TMG e redução nas variáveis PCG, IVG e TG. O genótipo CSF 20 apresentou comportamento semelhante, exceto para as variáveis IVG e TMG, as quais foram afetadas pelo NaCl a partir da concentração de 150 mM. os genótipos mostram respostas diferenciadas quanto às condições de déficit hídrico e salinidade, sendo que as sementes de sorgo do genótipo CSF 18 apresentam germinação e vigor superiores em relação às do genótipo CSF 20.Termos para indexação: Sorghum bicolor, qu...

A germinação lenta e desuniforme das sementes de palmeiras acarreta problemas na propagação das espécies pertencentes a esta família, dificultando, principalmente, a produção de mudas em escala comercial. Esse trabalho objetivou determinar o efeito do tamanho da semente, de substratos e do ambiente na emergência de plântulas de Copernicia hospita Martius. As sementes foram submetidas aos tratamentos: substratos [areia vermelha + bagana de carnaúba + húmus (2,5:2,5:1 em volume) e solo + arisco + composto orgânico Polefértil® (2:2:1 em volume)]; ambientes (pleno sol e casa de vegetação); e tamanho de sementes (pequena, média, grande e mistura). Os tratamentos foram comparados quanto à percentagem de emergência, avaliada aos 60 dias após a semeadura, índice de velocidade e tempo médio de emergência. Os fatores analisados não influenciam no percentual de emergência de plântulas. Sementes de C. hospita oriundas da mistura e de tamanho pequeno, semeadas em ambos os substratos analisados, sob casa de vegetação, proporcionam emergência mais rápida das plântulas.

No abstract

Cereus jamacaru, a Cactaceae found throughout northeast Brazil, is widely used as cattle food and as an ornamental and medicinal plant. However, there has been little information about the physiological and biochemical aspects involved in its germination. The aim of this study was to investigate its reserve mobilization during germination and early seedling growth. For this, C. jamacaru seeds were germinated in a growth chamber and collected at 0, 2, 4, 5, 6, 8 and 12 days after imbibition for morphological and biochemical analyses. Dry seeds had wrinkled seed coats and large, curved embryos. Lipids were the most abundant reserve, comprising approximately 55% and 65% of the dry mass for cotyledons and the hypocotylradicle axis, respectively. Soluble sugars and starch were the minor reserves, corresponding to approximately 2.2% of the cotyledons' dry mass, although their levels showed significant changes during germination. Soluble proteins corresponded to 40% of the cotyledons' dry mass, which was reduced by 81% at the final period of germination compared to dry seeds. C. jamacaru seed can be classified as an oil seed due to its high lipid content. Moreover, lipids were the main reserve mobilized during germination because their levels were strongly reduced after seed germination, while proteins were the second most utilized reserve in this process.

Although it has been known that the seed's physiological potential affects its response to osmoconditioning and abiotic stresses, researches involving seed aging and priming associated to abiotic stresses are scarce. The aim of this work was to evaluate the role of seed priming on salt tolerance in sorghum seedlings from seeds with two vigor levels (aged or non-aged) and to verify the organic and inorganic solute contributions as osmoregulators in NaClstressed seedlings from aged and primed seeds. The combinations of two seed vigor levels (aged or not), two seed types (primed or not) and two salinity levels (exposed to NaCl at 100 mM or not) were evaluated. In low physiological quality seeds (aged seeds), priming provided an attenuation of salinity's negative effects (0 or NaCl at 100 mM) on seedling growth. The accumulation of Na + and Cl -ions in NaCl-stressed sorghum seedling shoot from primed seeds indicate a plant osmotic adjustment induced by seed priming, which was efficient in reducing the osmotic stress caused by salinity. Proline was the main organic solute that contributed to osmoregulation in NaCl-stressed sorghum seedling shoot and its levels increased due to seed priming. Changes in inorganic and organic solute contents, in both shoot and roots, could have been induced by seed priming and as a function of salt stress tolerance, although the changes in these organs were poorly related to each other.

RESUMO.Mesmo tendo-se avançando nas técnicas de produção de mudas, ainda existem muitos problemas a serem solucionados, principalmente no que se refere ao desenvolvimento do sistema radicular das mudas, em função das características dos recipientes utilizados. O objetivo do trabalho foi determinar o efeito do tamanho do recipiente e do tempo de cultivo da planta na produção de mudas de Copernicia hospita Martius. Sementes extraídas de frutos em estádio visual de maturação foram pré-germinadas e semeadas em sacos plásticos de 20 x 30, 28 x 40 e 40 x 60 cm, contendo como substrato a mistura de arisco + areia vermelha + esterco bovino curtido (2:1:1). Após a semeadura, os recipientes foram mantidos por três, seis ou nove meses em pleno sol. Nenhum dos recipientes analisados, durante seus respectivos períodos de cultivo, influenciou as variáveis de crescimento utilizadas na avaliação das respostas da planta. O tamanho dos recipientes não influenciou na formação das mudas de C. hospita; contudo, em função da economia e praticidade, recomenda-se a utilização do recipiente com dimensões de 20 x 30 cm. O tempo de cultivo, de nove meses, forma mudas mais vigorosas.Palavras-chave: palmeira, propagação, restrição radicular.ABSTRACT. Growth period and plastic pots for Copernicia hospita nursery plants production. Even though advances have been made in the techniques of seedling production, there are still many problems to be solved, especially with regard to the development of the root system of seedlings, depending on the containers used. The objective of this study was to determine the effect of recipient size and the plant cultivation time in the production of C. hospita seedlings. Seeds of carnauba (Copernicia hospita Martius) obtained from mature fruit, were pre-germinated and sown in plastic 20 x 30, 28 x 40 and 40 x 60 cm bags, within a substrate of sandy loam + red sand + cured cow manure (2:1:1). After sowing, the bags were kept for 3, 6 or 9 months at a place with direct sunlight. The variables of growth of the plants were not influenced either by the size of the recipients or by the periods of exposure. Although the size of the bags did not influence the development of the plants, the 20 x 30 cm size should be more practical and economical to be used. The 9 months growth period gave more vigorous plants.