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ResumoDigitaria insularis é uma planta daninha altamente disseminada no Brasil. Trata-se de uma gramínea perene que possui alta capacidade de infestação por possuir pequenas sementes com grande poder germinativo e de dispersão. Além disso, essa planta daninha, uma vez perenizada, forma touceiras e pode reproduzir-se através de seus rizomas, caracterizando este estádio fenológico como de difícil controle. Com a confirmação de biótipos resistentes ao herbicida glyphosate, essa espécie tem-se tornado um grande problema para a agricultura, uma vez que inibidores da EPSPS são os únicos herbicidas capazes de controlar essas espécies sem restrições quanto ao estádio fenológico. Fica evidente que o controle eficaz do capim-amargoso não se restringe a um único herbicida, bem como a uma única aplicação. Seu monitoramento deve ser constante, haja vista que se trata de uma planta daninha perene, altamente adaptada às condições brasileiras, com alto poder de infestação e que gera grandes prejuízos para a agricultura, reduzindo a produção e aumentando os custos com insumos. Esta revisão bibliográfica teve por objetivo compilar informações disponíveis na literatura, de modo que auxilie pesquisadores e profissionais das ciências agrárias nas tomadas de decisões e no manejo racional desta planta daninha.Palavras-chave adicionais: capim-amargoso; controle químico; glyphosate; plantas daninhas. AbstractDigitaria insularis is a highly pervasive weed in Brazil, it is a perennial grass that has high capacity infestation has small seeds with great power germination and dispersion moreover, this weed once perenizada, form clumps and can play through their rhizomes featuring this phenological stage as difficult to control. With the confirmation biotypes resistant to glyphosate, this species has become a major problem for agriculture, since, EPSPS inhibitors are the only herbicides capable of controlling these species no restrictions on the growth stage. It is evident that the effective control of sourgrass is not restricted to a single herbicide, as well as a single application, its monitoring should be constant, given that it is a perennial weed, highly adapted to Brazilian conditions, with high power of infestation and that causes extensive damage to agriculture, reducing production and increasing input costs. This literature review aim to compile information available in the literature, so that assist researchers and professionals in agricultural sciences in decision making and rational management of this weed.

The use of herbicides is widespread in weed management, and adjuvants are added to the spray solution to improve the effectiveness of applications. The goal was to evaluate the influence of adjuvants added to the herbicides saflufenacil and glyphosate, isolated or in combination, and the effects on the surface tension, deposition and effectiveness in post-emergence applications to control Conyza sumatrensis. Experiments were conducted completely randomized experimental design to evaluate surface tension (TS), deposition and herbicide effectiveness. The treatments were glyphosate, glyphosate + saflufenacil and saflufenacil with or without the adjuvants Natur’al óleo®, Assist®, Aterbane®, Sillwet L-77 and Dash HC® (surface tension). For the experiments about mixture deposition and herbicide effectiveness, the factorial scheme 3 x 5 was adopted in the experiment performed in April, where factor A corresponded to the combination of the herbicieds glyphosate, saflufenacil and glyphosate + saflufenacil, and factor B was the addition of the adjuvants Natur’al óleo®, Assist®, Aterbane®, Sillwet L-77. For experiments conducted in November, the adjuvant Dash HC® was added, and the 3x6 factorial design was adopted. The adjuvants reduced the ST of the herbicide mixture, and Silwet L-77® was the most effective one. However, the ST reduction did not influence the mixture deposition on C. sumatrensis plants. The use of adjuvants did not result in an effective control for the applications with sole glyphosate.

This paper announces a database on the taxonomy, distribution and host plants of mites of the family Tenuipalpidae Berlese (Acari: Tetranychoidea), available online at https://www.tenuipalpidae.ibilce.unesp.br/. In the Tenuipalpidae Database the recorded world distribution and range of host plants are provided for each tenuipalpid species, including synonyms, with a list of all relevant publications.

Soil seedbank management via collecting clippings may be a means of combatting herbicide resistance in annual bluegrass (Poa annua L.) by minimizing recruitment from the deposition of viable seed into the soil. Our objective was to assess the germinability of annual bluegrass seed in spring to determine when collecting clippings would be most impactful. Research was conducted across 2019 and 2020 in five locations: Knoxville, TN; Starkville, MS; Griffin, GA; West Lafayette, IN; and University Park, PA. Annual bluegrass seed was harvested every 100 growing degree-days (GDD 0C ; base 0 ˚C with accumulation beginning on 1 January each year from 400 to 1,100 GDD 0C . Seeds from each harvest timing were placed on moistened blotter paper in petri dishes and randomized in a growth chamber set to a 77:68 ˚F and 8:16 h light-dark cycle. Germination was assessed every 3 d until 21 d of incubation.Cumulative germination percentage after 21 d of incubation increased at research locations in northern latitudes. In Tennessee, germination was greatest from 600 to 900 GDD 0C . In Indiana, germination did not exceed 50% until 600 GDD 0C and increased with GDD 0C accumulation. Clippings should not be collected until at least 600 GDD 0C in these locations. In Pennsylvania, little variation existed among GDD 0C harvest times, indicating that clipping collection may be a valuable practice any time mature seedheads are present. Turfgrass managers should consider geographic location when selecting a time to implement clipping collections and will probably need to conduct multiple clipping collection events. INTRODUCTIONAnnual bluegrass (Poa annua L.; ABG) is a common and problematic weed in turfgrass because of the species' light green color, prolific spring seedhead (inflorescence) produc-Abbreviations: ABG, annual bluegrass; CGP, cumulative germination percentage; GDD, growing degree-days; GDD 0C , growing degree-days with a base of 0 ˚C.

O uso de herbicidas em pré-emergência da cultura da soja é uma ótima ferramenta para o manejo de plantas daninhas. Porém é importante conhecer os efeitos de herbicidas, a fim de evitar decréscimo na produtividade. Assim, o objetivo deste experimento foi avaliar a sensibilidade de três cultivares de soja submetidas à aplicação do herbicida diclosulam em pré-emergência em solos de textura argilosa e média. Os experimentos foram conduzidos em casa de vegetação no delineamento de blocos inteiramente casualizados com quatro repetições, em esquema fatorial 6x2, onde o fator A correspondeu a diferentes épocas de pulverização do herbicida diclosulam, todas em pré-emergência, sendo: testemunha sem aplicação, 28, 21, 14, 7 e 0 dias antes da semeadura (DAS) da soja e o fator B correspondeu as texturas dos solos. As cultivares utilizadas foram a M 6410 IPRO, NS 6906 IPRO e NS 7000 IPRO. A semeadura ocorreu ao final das pulverizações dos tratamentos no dia 0 DAS. Avaliou-se o índice de velocidade de emergência (IVE), porcentagem de fitotoxicidade, altura de plantas, massa seca da parte aérea e massa seca do sistema radicular. De acordo com as metodologias empregadas neste experimento, o herbicida diclosulam aplicado em pré-emergência nos solos de textura argilosa e média é seguro para as cultivares de soja analisadas, pois não provocou efeitos negativos no desenvolvimento das plantas.

The taxonomic history of the genus Tenuipalpus Donnadieu is discussed and Tenuipalpus caudatus (Dugès) (=Tenuipalpus palmatus Donnadieu) is redescribed based on specimens from Portugal intercepted at ports of entry in the United States, and references including photographic records of the neotype of T. caudatus. In addition, a proposed new species, Tenuipalpus erbei sp. nov. is described from Costa Rica. Our results show that T. caudatus, T. erbei sp. nov. and another 36 known species of Tenuipalpus share a pair of lateral body projections associated with setae c3, considered a synapomorphy for the newly defined group, Tenuipalpus sensu stricto. We also show that its members share other character states, although these features are found elsewhere in Tenuipalpus and also in Ultratenuipalpus, indicating their origins are within Tenuipalpus. A list of Tenuipalpus sensu stricto species is presented.

With the possibility of using ammonium glufosinate in corn, studies on its association with other herbicides are essential. The aim of this study was to assess weed control and herbicide selectivity in association with ammonium glufosinate in corn containing the pat and cp4-epsps genes. The experiment was carried out under field conditions in two sites in a randomized block design with four replications. Treatments consisted of ammonium glufosinate, glyphosate, ammonium glufosinate + glyphosate, ammonium glufosinate + nicosulfuron, ammonium glufosinate + atrazine, ammonium glufosinate + tembotrione, ammonium glufosinate + mesotrione, ammonium glufosinate + carfentrazone ethyl, ammonium glufosinate + bentazon, ammonium glufosinate + 2,4-D, control without weeding, and hand-weeded control. Visual assessments were performed regarding damage, electron transport rate in photosystem II (ETR), ammonia quantification, height, and grain yield of corn plants, as well as weed control at both sites. The application of ammonium glufosinate and its associations did not provide a reduction in productivity when compared to the hand-weeded control. Some treatments presented higher levels of visual damage and ammonia accumulation, but without a yield reduction. Therefore, herbicide mixture with ammonium glufosinate may be an alternative to weed control without damaging corn crop, which presents in its genetic constitution the cp4-epsps and pat genes. Planta Daninha 2019; v37:e019184453 KRENCHINSKI, F.H. et al. Ammonium glufosinate associated with post-emergence herbicides in corn with the cp4-epsps and pat ...2 visual e acúmulo de amônia, porém sem redução de produtividade. Portanto, a mistura de herbicidas com o amônio-glufosinate pode ser uma alternativa para o controle de plantas daninhas, sem causar danos à cultura do milho, que apresenta na sua constituição genética os genes cp4-epsps e pat.Palavras-chave: acúmulo de amônia, fosfinotricina, fluxo de transporte de elétrons, resistência a herbicidas, Zea mays.