Inibidores de síntese de giberelinas e crescimento de mudas de mangueira 'Tommy Atkins' Synthesis inhibitors of gibberellins and mango 'Tommy Atkins' seedlings growth

A mangicultura no semiárido brasileiro destaca-se pelos altos rendimentos, pela qualidade do fruto produzido e pela possibilidade de produção durante todo o ano, devido a condições climáticas e tecnologias para o manejo do crescimento vegetativo e da floração, com uso da irrigação, podas e retardantes vegetais. O paclobutrazol aplicado ao solo é utilizado no manejo da produção da mangueira na maioria dos pomares. Entretanto, há a necessidade de identificar retardantes vegetais que possam ser aplicados via foliar, de forma a minimizar os resíduos no solo e evitar o uso de quantidades inadequadas ao longo dos anos. Assim, este trabalho teve como objetivo avaliar retardantes vegetais aplicados via foliar na inibição do crescimento vegetativo de mudas de mangueira 'Tommy Atkins'. Prohexadione-Ca, etil-trinexapac e cloreto de chlormequat, aplicados via foliar, na dose de 1g i.a. planta-1, regulam o crescimento de ramos vegetativos, mas apresentam tempo diferenciado de atividade nas mudas, sendo 20 dias para prohexadione-Ca, 30 dias para cloreto de chlormequat e 45 dias para etil-trinexapac, nas condições em que o experimento foi conduzido.<br>The mango in the Brazilian semi-arid region stands out in the national scenario due to high yields and fruit quality, as well as to the possibility of all-year production due to climatic conditions and technologies which allow the management of plant growth and flowering through irrigation, pruning and use of plant growth regulators. Paclobutrazol applied to the soil is used for the production management of mangoes in most of the orchards. However, it is necessary to identify plant growth regulators which might be applied to the leaves, so as to minimize the risk of residues in the soil and to avoid inadequate application levels over several years. The present paper aimed at evaluating the effect of plant growth regulators applied to the leaves, regarding their efficiency for flowering management of mango 'Tommy Atkins'. Prohexadione-Ca, trinexapac-ethyl and chlormequat chloride at the dosage of 1.0 g a.i. plant-1 acts on the regulation of vegetative growth; the period of efficiency of the products applied to the leaves lasted 20 days for prohexadione-Ca, 30 days for chlormequat cloride, and 45 days for trinexapac-ethyl

Distributional patterns and possible origin of leafhoppers (Homoptera, Cicadellidae)

The zoogeographical distribution of 42 cicadellid subfamilies and their assigned tribes and genera is compiled with distributional maps and proposed dispersal pathways of genera that are shared interzoogeographically. Possible origin of the subfamilies and tribes is proposed in an ancestral context from which the more modern extant groups evolved whereas origin of genera is in a more modern context. Notwithstanding their complex biogeography, the distributional data of the higher groups indicate that all of the cosmopolitan and near cosmopolitan subfamilies arose during early Cretaceous or possibly the late Jurassic period (140-116 m.y.a.) when continental drift was in its early stages. Nearly all of the New World and some Old World subfamilies are considered of more recent origin (late Cretaceous-Tertiary). Ninety percent of the known genera (2,126) are endemic to their respective zoogeographical region and subregion, thus indicating relatively high host specificity and low rate of dispersal. The majority (76%) of known extant genera are pantropical in origin, suggesting early or possible Gondwanaland origin of their ancestors. Dispersal pathways of genera shared by more than one zoogeographical region were generally south to north (Neotropical/Nearctic, Oriental/Palaearctic) or west to east (Palaearctic/Nearctic, Oriental/Australian), from regions of high diversity to regions of low diversity and from warmer climates to cooler climates. The most diverse and richest leafhopper fauna are present in the Neotropical and Ethiopian regions although taxal affinities between them are poorest. The most depauperate fauna are in the Nearctic region and in Australia, reflecting the impact of isolating and ecological factors on distribution and radiation. Ecological barriers were more evident between the Ethiopian and Oriental fauna than between any other zoogeographical combination. Taxal affinities appeared to be correlated with close continental proximities. Vicariance (physical) was the principal event that appealed to explain the distribution of many subfamilies and tribes whereas dispersal accounted for distribution of the majority of interzoogeographical genera

Large expert-curated database for benchmarking document similarity detection in biomedical literature search

Document recommendation systems for locating relevant literature have mostly relied on methods developed a decade ago. This is largely due to the lack of a large offline gold-standard benchmark of relevant documents that cover a variety of research fields such that newly developed literature search techniques can be compared, improved and translated into practice. To overcome this bottleneck, we have established the RElevant LIterature SearcH consortium consisting of more than 1500 scientists from 84 countries, who have collectively annotated the relevance of over 180 000 PubMed-listed articles with regard to their respective seed (input) article/s. The majority of annotations were contributed by highly experienced, original authors of the seed articles. The collected data cover 76% of all unique PubMed Medical Subject Headings descriptors. No systematic biases were observed across different experience levels, research fields or time spent on annotations. More importantly, annotations of the same document pairs contributed by different scientists were highly concordant. We further show that the three representative baseline methods used to generate recommended articles for evaluation (Okapi Best Matching 25, Term Frequency-Inverse Document Frequency and PubMed Related Articles) had similar overall performances. Additionally, we found that these methods each tend to produce distinct collections of recommended articles, suggesting that a hybrid method may be required to completely capture all relevant articles. The established database server located at https://relishdb.ict.griffith.edu.au is freely available for the downloading of annotation data and the blind testing of new methods. We expect that this benchmark will be useful for stimulating the development of new powerful techniques for title and title/abstract-based search engines for relevant articles in biomedical science. © The Author(s) 2019. Published by Oxford University Press