Physiological and vegetative behavior of banana cultivars under irrigation water salinity.

he purpose of the study was to evaluate the effect of salinity levels of irrigation water on physiology and growth of banana cultivars during the vegetative stage. The experiment was carried out following a completely randomized design in split plots, with four levels of salinity in irrigation water (0.5, 2.0, 3.0 and 4.0 dS m-1) and fourbanana cultivars (Pacovan, Prata Anã, BRS Platina and Princesa) with three repetitions. Stomatal conductance, transpiration, relative water content, leaf water potential and proline concentration were evaluated at 150 days after transplanting (DAT), besides plant height, stem diameter and leaf area. All variables showed sensitivity to the increase of salinity level of irrigation water. The results of soil water extraction, relative water content in leaf (RWC), leaf water potential and proline content differed (p ? 0.05) among the cultivars. Prata Anã and BRS Platina cultivars were the ones with lowest sensitivity, while Pacovan and BRS Princesa cultivars showed larger variation of soil water extraction and RWC with the increase in irrigation water salinity (electrical conductivity), being considered the ones of highest sensitivity to salinity in this study. Banana crop growth as a consequence of physiological effects was inhibited by the increase in water salinity, mainly in ?BRS Princesa? cultiva

First report of Anthracnose caused by Colletotrichum spaethianum on Allium fistulosum in Brazil.

The Welch onion (Allium fistulosum L.) is widely grown in temperate and subtropical regions worldwide and has many important culinary uses. The occurrence of anthracnose on Welch onion has been reported in Korea and is caused by Colletotrichum circinans (Kim et al. 2008). Since 2012, symptoms typical of anthracnose have been observed on Welch onions in a vegetable garden located in the Japanese Colony of Manaus, Amazonas, Brazil (59°59′06″ W; 03°04′16″ S). This disease occurred in 50% of the seedlings and the symptoms consist of brown necrotic spots that extend along the entire leaf. Acervuli collected directly from the leaves were plated onto potato dextrose agar (PDA) and then incubated at 25°C for three to four days. Single-spore cultures were obtained from three isolates from different plants. On PDA medium, the isolates initially produced white colonies, which then turned gray and had an orange-colored conidial mass. On Spezieller Nährstoffarmer Agar (SNA) medium (Leslie and Summerell, 2006), they formed numerous black structures such as sclerotia, setae, and acervuli. Conidia on SNA are hyaline, aseptate, curved or slightly curved, with a rounded apex and truncated base that is 13.1 to 20.2 μm long and 3.3 to 4.0 μm wide. The appressoria are solitary or in loose groups, dark brown, irregularly shaped, sometimes partially lobed, smooth-walled, and from 5.6 to 10.8 μm long and 4.3 to 8.2 μm wide. An alignment of the actin (ACT) and chitin synthase (CHS-1) partial gene sequences showed 100% identity with Colletotrichum spaethianum (Allesch.) Damm, P. F. Cannon & Crous (CBS 167.49). Maximum likelihood analysis was done using the published sequences of the ACT and CHS-1 genes from C. spaethianum and other Colletotrichum species that have curved conidia (Damm et al. 2009; Vieira et al. 2014). The individual data sets were combined using the web tool FaBox (1.41) and analysis with PAUP (1000 bootstrap replicates). Based on morphological characteristics and phylogenetic analysis, the isolates were identified as C. spaethianum. The sequences for the isolates obtained in the present study were deposited in GenBank (ACT Accession Nos. KT184300 to KT184302; CHS-1 Accession Nos. KT184303 to KT184305). The cultures were deposited in the Culture Collection of Microorganisms of the National Institute of the Amazonian Research (Instituto Nacional de Pesquisas da Amazônia, INPA) (INPA 2615, 2770, and 2774). Five Welch onion seedlings were sprayed with a conidial suspension (106 conidia/ml) for each isolate and control seedlings were sprayed with sterile water. Plants were covered with plastic bags and maintained at 28°C ± 2°C in a greenhouse and a 12-h photoperiod. Symptoms typical of anthracnose were induced five days postinoculation, and signs of the pathogen were observed at 12 days postinoculation. No symptoms were observed in the control plants. C. spaethianum was reisolated from symptomatic plants, completing Koch’s postulates. C. spaethianum has been described on Hosta sieboldiana in Germany, Lilium sp. in South Korea, Hemerocallis sp. in New Zealand (Damm et al. 2012), Hemerocallis fulva, Hemerocallis citrine, and Peucedanum praeruptorum in China (Yang et al. 2012; Guo et al. 2013), and Hemerocallis flava in Brazil (Vieira et al. 2014). To our knowledge, this is the first report of C. spaethianum on A. fistulosum. © 2016, American Phytopathological Society. All rights reserved

High-order Harmonic Generation and Dynamic Localization in a driven two-level system, a non-perturbative solution using the Floquet-Green formalism

We apply the Floquet-Green operator formalism to the case of a harmonically-driven two-level system. We derive exact expressions for the quasi-energies and the components of the Floquet eigenstates with the use of continued fractions. We study the avoided crossings structure of the quasi-energies as a function of the strength of the driving field and give an interpretation in terms of resonant multi-photon processes. From the Floquet eigenstates we obtain the time-evolution operator. Using this operator we study Dynamic Localization and High-order Harmonic Generation in the non-perturbative regime

What Does a Modern Anatomist Look like? Current Trends in the Training of Anatomy Educators

Anatomical sciences are foundational to the health professions, yet little is known about the qualifications of anatomy educators at the graduate and professional level in the United States. Moreover, there is concern that the number of qualified anatomy educators being trained may be insufficient to meet the growing demand posed by new and expanded programs in medicine and allied health specialties. The authors surveyed anatomists from across the country to (i) characterize the educational credentials of current anatomy educators and (ii) assess the perceived need for education‐focused postdoctoral positions or formal mentorships to prepare anatomists for teaching‐intensive faculty positions. To probe the survey responses more deeply, one‐on‐one interviews were conducted with eight individuals selected to represent a diverse sample of respondents in terms of institution, gender, and academic rank. Results indicate that 30–40% of educators at the graduate level and approximately 60% of those at the undergraduate level lack graduate coursework in histology, embryology, and neuroanatomy. Forty‐five percent of respondents had completed a postdoctoral fellowship. Eighty‐six percent replied “yes/maybe” to the question of whether an anatomy education postdoctoral fellowship would benefit doctoral graduates. The top 3 reasons for this recommendation were to (i) establish independent educational research, (ii) improve a publication record, and (iii) gain additional teaching experience. Notable weaknesses of education‐focused postdoctoral training were related to finances, fear of exploitation, and undervaluing of teaching. Moving forward, postdoctoral fellowships and other forms of postgraduate training may represent a key strategy for training anatomists in the current educational climate

Detecção de um begomovírus em amostras foliares de tomateiro com sondas não-radioativas.

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