Initial development and chemical components of sugarcane under water stress associated with arbuscular mycorrhizal fungi

ABSTRACT The objective of this study was to evaluate the effects of water stress levels in the soil and a mix (or: a mixed inoculum of four species: Claroideoglomus etunicatum, Gigasporas rosea, Acaulospora longula, Fuscutata heterogama) of arbuscular mycorrhizal fungi (AMF) on initial vegetative growth, fresh and dry biomass production, root colonization, phosphorus, proteins, enzymes and amino acid of the sugarcane variety RB 857515 under greenhouse conditions. The experiment was set in a randomized block design in a 2 x 2 factorial scheme with four treatments (T1 - 50% PC - pot capacity, with AMF; T2 - 100% PC with AMF; T3 - 50% PC without AMF; T4 - 100% PC without AMF) with 16 replicates. The water stress level of 50% PC decreased stem diameter and shoot and root fresh weight of sugarcane plants, as well as AMF in the soil and in plant roots. However, AMF and the water stress level of 50% PC, separately or combined, did not affect plant height, number of leaves, dry matter and contents of phosphorus, total soluble proteins, catalase, ascorbate peroxidase, polyphenoloxidase, peroxidase and proline of the sugarcane variety RB857515

Influência da adubação com esterco bovino e inoculação de fungos micorrízicos arbusculares no crescimento de mudas de Carica papaya L. (var. Formosa) Influence of fertilization with bovine manure and inoculation of arbuscular mycorrhizal fungi in the growth of Carica papaya L. 'Formosa' seedlings

Devido ao rápido crescimento do mamoeiro, poucos são os solos que, em condições naturais, podem satisfazer a sua demanda por nutrientes, sendo necessária a aplicação de fertilizantes minerais que favoreçam as plantas no período do transplantio para o campo. Os fungos micorrízicos arbusculares (FMA) são conhecidos por tornarem os seus hospedeiros mais resistentes aos estresses bióticos e abióticos, sendo por isso empregados na produção de mudas de diversas árvores frutíferas. Nesse trabalho objetivou-se avaliar a influência da inoculação de FMA e da aplicação de matéria orgânica no crescimento de mudas de mamoeiro (Carica papaya L. var. Formosa), em casa-de-vegetação. Mudas foram cultivadas em solo arenoso (caracterizado pelo baixo teor de P: 4 ppm), inoculado com FMA e adubado ou não com 50g de esterco bovino. O delineamento experimental foi inteiramente casualizado com seis tratamentos e três repetições: - inoculação com FMA nativos, com Gigaspora albida Schenck & Smith, ou com Scutellospora hetervgama (Nicol. & Gerd.) Walker & Sanders, com ou sem matéria orgânica O experimento foi avaliado a cada 10 dias, sendo aferidos os parâmetros: altura, diâmetro do caule e número de folhas. Diferenças significativas entre os tratamentos adubados e não adubados foram observados a partir do 30º dia Após 40 dias, as plantas inoculadas com os FMA nativos apresentaram melhor desenvolvimento do que as inoculadas isoladamente com G. albida ou S. hetervgama, em todos os parâmetros avaliados, tanto em solo adubado como em solo não adubado.<br>Due to the fast growth of papaya few are the soils that can satisfy its demand for nutrients under natural conditions, the application of mineral fertilizers that favor the plants in the period of the transplant to the field being necessary. The arbuscular mycorrhizal fungi (AMF) are known for making their hosts more resistant to biotic and abiotic stress, this being the reason why they have been employed for the seedling production of several types of fruit trees. The objectives of this work were to evaluate the influence of the inoculation of AMF and the application of organic matter in the growth of papaya (Carica papaya L. 'Formosa'), in a greenhouse. Seedlings were cultivated in sandy soil (characterized by a low P: 4ppm), inoculated with AMF and fertilized or not with 50g of bovine manure. The experimental design was entirely randomized with six treatments and three replicates: - inoculation with either native AMF, Gigaspora albida Schenck & Smith or Scutellospora hetervgama (Nicol. & Gerd.) Walker & Sanders with/without organic matter. The experiment was evaluated ev ery 10 days, considering the parameters: height, diameter of stem and number of leaves. Significant differences between fertilized and non fertilized treatments were observed on the 30th day. After 40 days, plants inoculated with native AMF presented better development than those inoculated separately with G. albida or S. heterogama, in both fertilized and non fertilized soils