ABJ(M) and Fractional M2's with Fractional M2 Charge

Recently Aharony, Bergman and Jafferis (ABJ) have argued that a 3d U(N+M)xU(N) Chern-Simons gauge theory at level (k,-k) may have a vacuum with N=6 supersymmetry only if M<k+1 and if a certain period of the B-field in a IIA background is quantized. We use a braneology argument to argue that N=3 supersymmetry may be preserved under the weaker condition that 2Nk>M(M-k)-1 with no restriction on the B-field. IIB brane cartoons and 11d supergravity solutions corresponding to N=3 vacua that do not preserve N=6 supersymmetry are argued to represent cascading gauge theories, generalizing the N=2 Seiberg duality conjectured by Giveon and Kutasov. While as usual the M2-brane charge runs as a result of the twisted Bianchi identity for *G_4, the M5-brane charge running relies on the fact that it wraps a torsion homology cycle.Comment: 16 pages, 3 eps figure

Pathogenicity and aggressiveness of Macrophomina phaseolina isolates to sorghum in Australia’s northern grains region

M. phaseolina, a soilborne pathogen, causing charcoal rot in more than 500 crop species Splitting sorghum stalks will show ash grey tissue or microsclerotia, the survival structure of the fungus, giving the internal stalk tissue a peppered look Causes major sorghum stalk rotting, which can lead to plant lodging Common during seasons with prolonged hot, dry weather or when other unfavourable environmental conditions stress the plant Despite the lack of formal quantification in Australia, significant yield losses have been associated to prevailing hot dry conditions resulting to widespread high incidences of charcoal rot and subsequent lodging The present work aims to compare pathogenicity and aggressiveness of isolates, from sorghum and other hosts from the northern region, to sorghu

2019 Australian Summer Grains Conference: Enduring Farm Profitability (ASCG 2019)

M. phaseolina, a soilborne pathogen, causing charcoal rot in more than 500 crop species Splitting sorghum stalks will show ash grey tissue or microsclerotia, the survival structure of the fungus, giving the internal stalk tissue a peppered look Causes major sorghum stalk rotting, which can lead to plant lodging Common during seasons with prolonged hot, dry weather or when other unfavourable environmental conditions stress the plant Despite the lack of formal quantification in Australia, significant yield losses have been associated to prevailing hot dry conditions resulting to widespread high incidences of charcoal rot and subsequent lodging The present work aims to compare pathogenicity and aggressiveness of isolates, from sorghum and other hosts from the northern region, to sorghu

Soil water dynamics and litter production in eucalypt and native vegetation in southeastern Brazil

High productivity of eucalypt plantations is the result of advances in research that have led to gradual improvements in intensive silvicultural technology. High productivity notwithstanding, eucalypt plantations remain the focus of environmental concerns. Our study aimed to compare the soil water regime, litter fall and nutrients dynamics either in a fragment of native forest or in an adjacent stand of growing eucalypt. We took field measurements during the first three years of eucalypt plantation in a sandy soil in the southeastern region of Brazil. Soil moisture and internal drainage were higher during the early stages of growth of the eucalypt stand, as compared with native vegetation. However, one and a half years after planting, available soil water was similar in both vegetations. Higher water availability under the eucalypt stand during the first year occurs because of silvicultural operations (soil preparation and weed control) and the small size of eucalypt trees; these factors increase water infiltration and decrease transpiration. Total leaf fall, over the study period, was similar for both ecosystems; however, differences were observed in the winter and early spring of 2010. The transfer of nutrients to soil by leaf fall was similar except for N and S, which was higher in native vegetation. Nitrogen concentration in the soil solution was higher in native vegetation, but K was higher under the eucalypt stand, mainly to a depth of up to 0.2 m

Suprimento de potássio em função da adubação potássica residual em um Latossolo Vermelho do Cerrado

Em alguns solos com baixos teores de potássio trocável, formas não trocáveis participam do suprimento às plantas. Há evidências de que a disponibilização do K não trocável depende mais da demanda das plantas pelo nutriente do que das propriedades do solo. O objetivo deste trabalho foi avaliar o suprimento e a exaustão de formas de K em um Latossolo Vermelho do Cerrado em decorrência da adubação potássica residual e do cultivo de Brachiaria ruziziensis (Syn. Urochloa ruziziensis). Amostras de solos foram coletadas na camada de 0-20 cm, em parcelas de um experimento de campo em que a soja vinha sendo adubada anualmente, por 10 anos, com 0, 60, 120 e 180 kg ha-1 de K2O. Em casa de vegetação, as amostras de solo receberam a aplicação de 0, 150 e 300 mg dm-3 de K e foram cultivadas com B. ruziziensis, com cinco cortes sucessivos. O suprimento de K às plantas dependeu mais do fertilizante recém-adicionado do que do efeito residual de adubações anteriores. O K não trocável foi responsável, ao longo do tempo, pela manutenção dos teores de K trocáveis e, na ausência de adubação potássica, constituiu a principal fonte de K para as plantas de B. ruziziensis. As plantas de B. ruziziensis possuem capacidade de extrair quantidade considerável de K do solo, confirmando sua importância como cultura de cobertura, na ciclagem do nutriente no solo