Management of soil cover and its influence on phytosociology, physiology and fig production

The fig stands out as an important source of food for the human diet, especially minerals and fibers. Weeds are a major concern in the conduct of fig orchards. Therefore, the objective of this study was to evaluate the effect of management of vegetable cover of soil (CVS) on weed phytosociology, physiological characteristics and fig production. The experimental design was a randomized complete block design with four replications. The treatments consisted of six CVS managements: cover maintenance, weeding, lodging, mowing, application of herbicides diquat and glyphosate. For the constitution of the vegetal cover a consortium of three winter forage species, vetch and black oats sowed and the ryegrass remaining in the area of previous years were used. Thus, we evaluated the phytosociology of weeds present in the area, at two different times, assigning parameters related to frequency, density and abundance, which establish the species importance value index (IVI), besides the dry mass of the aerial part of the weeds. Physiological parameters and total fruit yield were evaluated at the end of the crop cycle. The different CVS management methods influenced the weed community, mainly in the diversity, density and dry mass of the aerial part. There is no interference in the physiological variables of the fig plants and in the total production of fig fruits. We highlight the maintenance of coverage and lodging as the most promising for the management of weeds found fig orchards.The fig stands out as an important source of food for the human diet, especially minerals and fibers. Weeds are a major concern in the conduct of fig orchards. Therefore, the objective of this study was to evaluate the effect of management of vegetable cover of soil (CVS) on weed phytosociology, physiological characteristics and fig production. The experimental design was a randomized complete block design with four replications. The treatments consisted of six CVS managements: cover maintenance, weeding, lodging, mowing, application of herbicides diquat and glyphosate. For the constitution of the vegetal cover a consortium of three winter forage species, vetch and black oats sowed and the ryegrass remaining in the area of previous years were used. Thus, we evaluated the phytosociology of weeds present in the area, at two different times, assigning parameters related to frequency, density and abundance, which establish the species importance value index (IVI), besides the dry mass of the aerial part of the weeds. Physiological parameters and total fruit yield were evaluated at the end of the crop cycle. The different CVS management methods influenced the weed community, mainly in the diversity, density and dry mass of the aerial part. There is no interference in the physiological variables of the fig plants and in the total production of fig fruits. We highlight the maintenance of coverage and lodging as the most promising for the management of weeds found fig orchards

Sistemas de manejo do solo e sua influência no banco de sementes de plantas daninhas

The objective of this work was to evaluate the density and composition of the soil weed seed bank when bean, corn, and soybean are cultivated in the no-tillage system (NTS) in rotation with winter cover crop species and in the conventional tillage system (CTS). The experiment was installed in a complete randomized block design with three replicates. The evaluation of the seed bank was performed on soil samples (0–10 and 10–20 cm) in four points of each experimental unit, at 15, 30, 60, and 90 days of cultivation. Bean, corn, and soybean crops were sown in the NTS with different soil cover crops in rotation, as well as in the CTS. The NTS provided a more dense and abundant soil seed bank of the species Gnaphalium spicatum and Oxalis corniculata when corn, soybean, and bean were cultivated. The species Lolium multiflorum showed lower density and less seeds in the soil seed bank when the NTS was adopted. The use of the winter cover crops black oat and cow vetch, cultivated individually or in consortium, resulted in a lower density of weed species, especially of L. multiflorum. The NTS provides a lower density of weed species in the soil seed bank than the CTS.O objetivo deste trabalho foi avaliar a densidade e a composição do banco de sementes de plantas daninhas do solo ao se cultivar feijão, milho e soja no sistema plantio direto (SPD), em rotação com espécies de cobertura de inverno, e no sistema plantio convencional (SPC). O experimento foi instalado em campo, em delineamento de blocos ao acaso, com três repetições. A contagem do banco de sementes foi realizada em amostras de solo (0–10 e 10–20 cm) em quatro pontos de cada unidade experimental, aos 15, 30, 60 e 90 dias de cultivo. As culturas de feijão, milho e soja foram semeadas no SPD com diferentes coberturas vegetais do solo em rotação, bem como no SPC. O SPD proporcionou banco de sementes do solo com maior densidade e abundância das espécies Gnaphalium spicatum e Oxalis corniculata com o cultivo de milho, soja e feijão. A espécie Lolium multiflorum teve menor densidade e menos sementes no banco do solo ao se adotar o SPD. O uso das coberturas de inverno aveia-preta e ervilhaca, em cultivo isolado ou em consórcio, proporcionou menor densidade de espécies de plantas daninhas, em especial de L. multiflorum. O SPD proporciona menor densidade de espécies de plantas daninhas no banco de sementes do solo que o SPC

Fitotoxicidade de clomazone associado com dietholate à cultura do trigo

Nowadays it has become important to test new alternatives herbicide molecules, even if they are not registered for the control of weeds that infest wheat, to evaluate the phytotoxicity to culture and the ability to manage resistant weeds to the products used for this purpose. Thus, an experiment was conducted to evaluate the Phytotoxicity of clomazone associated or not to the dietholate safener applied on wheat. The experiment was conducted in a completely randomized design, arranged in a factorial scheme (5 x 4) + 2 + 2, with four replications. In the factor allocated to dietholate doses (0, 120, 240, 360 and 480 g per 100 kg of seed) and the B clomazone doses (0, 198, 396 and 594 g ha-1). Additional Treatments were the control treatments infested and without the application of herbicide, and the application in post-emergence of iodosulfuron-methyl (5 g ha-1) and pyroxsulam (18 g ha-1). The increase in clomazone doses caused increased phytotoxicity to wheat, with or without the safener. The dietholate showed no ability to protect the wheat from the phytotoxic effects of the herbicide clomazone. The use of clomazone associated with dietholate for weed control on wheat is not recommended. The pyroxsulam was the herbicide that caused minor injuries to wheat.Na atualidade torna-se importante testar novas alternativas de moléculas herbicidas, mesmo que não sejam registradas para o controle de plantas daninhas infestantes do trigo, para avaliar a fitotoxicidade à cultura e a possibilidade de manejar plantas daninhas resistentes aos produtos utilizados para esse fim. Diante disso, um experimento foi realizado para avaliar a fitotoxicidade do herbicida clomazone associado ou não ao safener dietholate aplicados à cultura do trigo. O experimento foi realizado em delineamento inteiramente casualizado, arranjado em esquema fatorial (5 x 4) + 2 + 2, com quatro repetições. No fator A alocou-se as doses de dietholate (0, 120, 240, 360 e 480 g para 100 kg de semente) e o no B as doses de clomazone (0, 198, 396 e 594 g ha-1). Os tratamentos adicionais foram constituídos pelas testemunhas infestadas e sem herbicida, e a aplicação em pós-emergência de iodosulfuron-methyl (5 g ha-1) e pyroxsulam (18 g ha-1). O incremento das doses de clomazone ocasionou o aumento da fitotoxicidade ao trigo, associado ou não ao protetor. O dietholate não apresentou capacidade de proteger o trigo dos efeitos fitotóxicos do herbicida clomazone. Não é recomendado o uso do clomazone associado ao diethole para o controle de plantas daninhas infestantes do trigo. O pyroxsulam foi o herbicida que causou menores injúrias ao trigo

Uso de clomazone associado ao safener dietholate para o manejo de plantas daninhas na cultura do trigo

The intensive and repeated use of the chemical control method in the wheat crop selected populations of turnip (Raphanus raphanistrum and R. sativus) and ryegrass (Lolium multiflorum) resistant to herbicides, especially from the groups of ALS‑, ACCase‑ and EPSPS‑inhibitors. It is important to rotate the herbicide mechanisms of action to manage populations of resistant weeds, both in burndown and after planting. Thus, this work aimed to assess the effectiveness of the herbicide clomazone in the control of ryegrass and turnip associated or not to dietholate safener protection in wheat crop. The first experiment was conducted in a completely randomized design (CRD), with four replications. Dietholate doses (0, 120, 240, 360 and 480 g per 100 kg of seeds of wheat cultivar TBIO Itaipu) were associated to clomazone doses (0, 198, 396 and 594 g ha‑1) sprayed pre-emergence. The second experiment comprised infested and weeded control treatments, the pre-emergence application of clomazone + dietholate (396 g ha-1 + 240 g per 100 kg seed) and post-emergence application of iodosulfuron-methyl (5 g ha-1) or pyroxsulam (18 g ha-1). The treatment of wheat seeds with dietholate did not affect the control of ryegrass and turnip by clomazone when applied pre-emergence. Clomazone, even when sprayed at low doses, presented ryegrass control above 80% and can be used to control resistant biotypes of this weed to EPSPs‑, ALS‑ and ACCase‑inhibitors. Iodosulfuron-methyl and pyroxsulam showed excellent control of turnip and satisfactory control of ryegrass.O uso intensivo e repetido do método químico de controle na cultura do trigo selecionou populações de nabo (Raphanus raphanistrum e R. sativus) e azevém (Lolium multiflorum) resistentes a alguns herbicidas, em especial aos inibidores das enzimas ALS, ACCase e EPSPs. Para manejar as populações de plantas daninhas resistentes, é importante rotacionar os mecanismos de ação de herbicidas, tanto na dessecação como nas aplicações realizadas após a implantação da cultura. Assim, objetivou-se com este trabalho avaliar a eficácia do herbicida clomazone no controle de azevém e nabo, associado ou não ao protetor dietholate, na cultura do trigo. Os experimentos foram conduzidos em delineamento inteiramente casualizado (DIC) com quatro repetições. No ensaio 1 foram testadas doses de dietholate (0, 120, 240, 360 e 480 g para 100 kg de sementes de trigo cultivar TBIO Itaipu) e de clomazone (0, 198, 396 e 594 g ha-1) aplicado em pré-emergência. No ensaio 2, instalado de modo simultâneo ao ensaio 1, os tratamentos foram constituídos pela testemunha infestada, testemunha capinada, clomazone + dietholate (396 g ha-1 + 240 g para 100 kg de semente) – aplicado em pré-emergência, iodosulfuron-methyl (5 g ha-1) e pyroxsulam (18 g ha-1) – aplicados em pós-emergência. O tratamento das sementes de trigo com dietholate não interferiu no controle de azevém e nabo pelo clomazone aplicado em pré-emergência. O clomazone, mesmo aplicado em baixas doses, apresentou controle de azevém acima de 80%, podendo ser utilizado para o controle de biótipos resistentes aos herbicidas inibidores da EPSPs, ALS e ACCase. O iodosulfuron-methyl e o pyroxsulam apresentaram excelente controle de nabo e satisfatório de azevém

ASSOCIAÇÃO DE HERBICIDAS PARA O MANEJO DE PLANTAS DANINHAS EM MILHO

Corn is an important crop for agriculture, playing a fundamental role in animal and human feed and energy production. Therefore, the purpose of this study was evaluate the effectiveness, selectivity and effects on corn physiological and productive characteristics after herbicide application either isolated or in tank mix. The procedure adopted was randomized blocks design, with four replications each. The treatments, glyphosate, [atrazine + simazine], nicosulfuron, mesotrione, tembotrione, plus a weeded control were used alone or in a tank mixture. It was evaluated the herbicide phytotoxicity in AG 9025 PRO3 hybrid corn, as well as the weed control of alexander grass and crabgrass at 7, 14, 21 and 28 days after treatment (DAT). At 50 DAT, variables related to the grain physiological characteristics were also measured. Finally, during harvest, grain yield was determined. All evaluations showed that phytotoxicity caused by herbicides was not visually perceptible in AG 9025 PRO3 corn hybrid. The control was effective in treatments that presented in tank mix treatments glyphosate with nicosulfuron and tembotrione. The physiological characteristic affected after herbicide application was photosynthesis, which, when compared to other treatments, showed better results with nicosulfuron and mesotrione. Herbicides did not interfere in corn grain yield. Glyphosate associated with other herbicides used in corn crops shows to be a valuable practice to improve and accelerate the weed control studied with selectivity to the crop.O uso de herbicidas para o controle de plantas daninhas na cultura do milho tem sido uma prática muito comum pelos produtores, sendo aplicados de modo isolado ou em mistura em tanque. Diante disso, o objetivo do trabalho foi avaliar a eficiência, a fitotoxicidade, o efeito em características fisiológicas e produtivas do milho após a aplicação de herbicidas de modo isolado ou em mistura em tanque. O experimento foi instalado a campo, no delineamento de blocos casualizados, com quatro repetições. Como tratamentos foram utilizados de forma isolada ou em mistura em tanque o glyphosate, [atrazine+simazine], nicosulfuron, mesotrione, tembotrione, mais uma testemunha capinada. Avaliou-se a fitotoxicidade dos herbicidas ao híbrido de milho AG 9025 PRO3, a eficiência no controle de papuã (Urochloa plantaginea) e milhã (Digitaria ciliaris) aos 7, 14, 21 e 28 dias após a aplicação dos tratamentos (DAT). Aos 50 DAT aferiu-se ainda as variáveis referentes às características fisiológicas do milho e na colheita determinou-se a produtividade de grãos. A fitotoxicidade ocasionada pelos herbicidas não foi perceptível ao híbrido de milho AG 9025 PRO3. O controle foi eficiente nos tratamentos que apresentaram a mistura em tanque de glyphosate com nicosulfuron e tembotrione. A taxa fotossintética aumentou com a aplicação de nicosulfuron e mesotrione ao se comparar com os demais tratamentos. A concentração interna de CO2, taxa de transpiração, condutância estomática de vapores de água, eficiência de carboxilação e uso eficiente da água não foram alteradas ao se usar os herbicidas isolados ou em mistura. A aplicação dos herbicidas não interferiu na produtividade de grãos de milho. A associação de glyphosate com outros herbicidas demonstra ser prática favorável para melhorar a eficácia de controle

Associação de herbicidas aplicados para o controle de plantas daninhas em soja resistente ao glyphosate

In order to bypass cases of glyphosate-resistant weeds, it becomes necessary to use herbicides with other action mechanisms. The goal of this work was to evaluate the effectiveness and selectivity of herbicides with isolated or tank mix application for the management of soybean-infesting glyphosate-resistant weeds. Treatments were applied sequentially, during pre-emergence: clomazone (900 g ha-1 a.i.); flumioxazin (50 g ha-1 a.i.); diclosulam (35.02 g ha-1 a.i.); s-metolachlor (1152 g ha-1 a.i.); sulfometuron + chlorimuron-ethyl (18.75 + 18.75 g ha-1 a.i.); pendimethalin (1250 g ha-1 a.i.); sulfentrazone (250 g ha-1 a.i.); sulfentrazone + chlorimuron-ethyl (250 + 20 g ha-1 a.i.); imazethapyr + sulfentrazone (100+250 g ha-1 a.i.) and imazaquin (150 g ha-1 a.i.) and, during post-emergence, glyphosate was used over these treatments (1080 g ha-1 a.e.). During post-emergence, glyphosate was applied in an isolated manner (1080 g ha-1 a.e.) and, mixed in the sprayer tank with glyphosate (1080 g ha-1 a.e.), imazethapyr (100 g ha-1 a.i.), clethodim (96 g ha-1 a.i.) and chlorimuron-ethyl (20 g ha-1 a.i.), plus the infested and weeded control samples. The experimental area was infested with 75% of creeping signalgrass plants (Urochloa plantaginea) and 25% of summergrass (Digitaria ciliaris), at the average densities of 133 and 45 plants m-2, respectively. At 14 and 21 DAT, the application of glyphosate + [sulfometuron + chlorimuron-ethyl] caused a 67 and 62% phytotoxicity to soybean, respectively. In order to control summergrass and creeping signalgrass, this very mixture presented an 88% index at 21 DAT, whereas control for the other treatments exceeded 91% during all evaluated periods. All the evaluated treatments caused over 91% control of both weeds, except for glyphosate + [sulfometuron + chlorimuron-ethyl]. The associations of herbicides to glyphosate caused weed control and were selective to soybean, except for sulfometuron + chlorimuron-ethyl, which presented lower control and high phytotoxicity. Some herbicides damaged the yield components of soybean, but only the sulfometuron + chlorimuron-ethyl mixture caused a reduction in grain productivity.Para contornar os casos de plantas daninhas resistentes ao glyphosate torna-se necessário o uso de herbicidas com outros mecanizamos de ação. Objetivou-se com o trabalho avaliar a eficácia e a seletividade de herbicidas aplicados isolados ou em mistura de tanque para o manejo de plantas daninhas infestante da soja resistente ao glyphosate. Os tratamentos foram aplicados de forma sequencial, em pré-emergência: clomazone (900 g ha-1 i.a.); flumioxazin (50 g ha-1 i.a.); diclosulam (35,02 g ha-1 i.a.); s-metolachlor (1152 g ha-1 i.a.); sulfometuron + chlorimuron-ethyl (18,75 + 18,75 g ha-1 i.a.); pendimethalin (1250 g ha-1 i.a.); sulfentrazone (250 g ha-1 i.a.); sulfentrazone + chlorimuron-ethyl (250 + 20 g ha-1 i.a.); imazethapyr + sulfentrazone (100 + 250 g ha-1 i.a.) e imazaquin (150 g ha-1 i.a.) e em pós-emergência sobre esses mesmos tratamentos usou-se o glyphosate (1080 g ha-1 e.a.). Em pós-emergência aplicou-se de modo isolado o glyphosate (1080 g ha-1 e.a.) e misturados ao tanque do pulverizador com glyphosate (1080 g ha-1 e.a.), imazethapyr (100 g ha-1 i.a.), clethodim (96 g ha-1 i.a.) e chlorimuron-ethyl (20 g ha-1 i.a.), mais as testemunhas infestada e capinada. A área experimental estava infestada com uma porcentagem de 75% de plantas de papuã (Urochloa plantaginea) e 25% com plantas de milhã (Digitaria ciliaris), nas densidades médias de 133 e 45 plantas m-2, respectivamente. Aos 14 e 21 dias após a aplicação dos tratamentos (DAT) a aplicação de glyphosate + [sulfometuron + chlorimuron-ethyl] ocasionou fitotoxicidade à soja de 67 e 62% respectivamente. Para o controle de milhã e papuã essa mesma mistura apresentou índice de 88% aos 21 DAT, sendo que o controle para os demais tratamentos ultrapassou os 91% em todas as épocas avaliadas. Todos os tratamentos avaliados ocasionaram controle das duas plantas daninhas maior que 91%, exceto o glyphosate + [sulfometuron + chlorimuron-ethyl]. As associações dos herbicidas ao glyphosate ocasionaram controle das plantas daninhas e foram seletivas a soja, com exceção do sulfometuron + chlorimuron-ethyl, que apresentou menor controle e elevada fitotoxicidade. Alguns herbicidas prejudicaram os componentes de rendimento da soja, porém somente a mistura de sulfometuron + chlorimuron-ethyl apresentou diminuição da produtividade de grãos

COMPETITIVE ABILITY OF BEAN CULTIVARS WITH HAIRY BEGGARTICKS

Weed interference is a factor that limits the productivity of beans and, among these, hairy beggarticks is one of the main species competing with the crop for environmental resources. Thus, the aim of this study is to evaluate the competitive ability of black bean cultivars (BRS Campeiro, IPR Uirapuru, SCS204 Predileto and BRS Supremo) in the presence of a biotype of hairy beggarticks. The experimental design is a completely randomized block with four replications. Treatments were arranged in a replacement series, consisting of a proportion of the crop and the hairy beggarticks: 100:0; 75:25; 50:50: 24:75, and 0:100, which corresponds to 40:0, 30:10, 20:20, 10:30, and 0:40 plant pots1. We accomplished competitive analysis through diagrams applied to the replacement series, as well as using relative competitive indices. The leaf area and shoot dry mass were evaluated at 40 days after emergence of the species. There was competition between bean cultivars and hairy beggarticks for the same environmental resources, causing negative interference in the growth of the species, independent of the proportion of plants. Bean cultivars had a lower relative loss by reducing the morphological variables of the hairy beggarticks, thereby demonstrating superiority in its competitive ability in relation to the weed. Interspecific competition is less damaging than intraspecific competition for both species

Effectiveness of different fungicide formulations and number of applications in controlling wheat leaf rust

<div><p>ABSTRACT Leaf rust (Puccinia triticina) is one of the most common diseases in wheat crops. For effective control of such disease, leaf application of mixtures of triazole and strobilurin fungicides is recommended. The aim of this study was to evaluate the efficacy of different fungicide formulations and numbers of applications in controlling wheat leaf rust in the cultivar TBIO Pioneiro 2010. Experimental design was completely randomized, 2x2 factorial arrangement, consisting of two fungicide formulations and two numbers of applications, as well as four replicates. Treatments were: azoxystrobin + tebuconazole, three and four applications; trifloxystrobin + prothioconazole, three and four applications; and a control treatment without fungicide application. For treatments with three applications, fungicides were applied at the phenological stages of: elongation, booting and flowering. For treatments with four applications, fungicides were applied at the phenological stages of: tillering, elongation, booting and flowering. The efficiency of fungicides on leaf rust control was analyzed based on the disease severity assessment by calculating the Area Under Disease Progress Curve (AUDPC). Severity data were obtained based on percentage scores of leaf area with visible disease symptoms/signs according to Cobb’s diagrammatic scale. Fungicides with azoxystrobin + tebuconazole and trifloxystrobin + prothioconazole showed efficient control of wheat leaf rust (higher than 85%). For yield components, there was no statistical difference between numbers of applications, but there was a statistical difference between fungicide formulations, except for grain yield. Furthermore, for yield components, all fungicide treatments significantly differed from control.</p></div

Characterisation of microbial attack on archaeological bone

As part of an EU funded project to investigate the factors influencing bone preservation in the archaeological record, more than 250 bones from 41 archaeological sites in five countries spanning four climatic regions were studied for diagenetic alteration. Sites were selected to cover a range of environmental conditions and archaeological contexts. Microscopic and physical (mercury intrusion porosimetry) analyses of these bones revealed that the majority (68%) had suffered microbial attack. Furthermore, significant differences were found between animal and human bone in both the state of preservation and the type of microbial attack present. These differences in preservation might result from differences in early taphonomy of the bones. © 2003 Elsevier Science Ltd. All rights reserved