Combination Of Cultural Practices Research Articles

Light partitioning strategies impact relative fitness of weeds and cover crops when drill-interseeding in corn

AbstractDrill-interseeding cover crops into corn (Zea mays L.) is an emerging establishment method in northern U.S. production regions. However, cover crop performance in interseeded systems remains variable, and creating environments that are conducive to cover crop but not weed growth is challenging. Cultural practices that partition resources between corn and interseeded cover crops have potential to improve performance if weeds are adequately managed. This study evaluated interactions among corn hybrids differing in leaf architecture (upright, pendulum), corn row spacing (76 cm, 152 cm), and interseeding timing (V3, V6) on light transmittance, relative fitness of cover crop species (cereal rye [Secale cereale L.], annual ryegrass (Lolium multiflorum Lam), red clover [Trifolium pratense L.]) and weeds, and corn grain yield at three U.S. Northeast locations. Results showed that light transmittance through the corn canopy was greater in 152-cm row spacing compared with 76-cm row spacing at the V6 growth stage, with the magnitude of difference increasing at the V10 corn growth stage. Corn hybrids had a marginal effect on light transmittance. The effect of row spacing and interseeding timing on fall cover crop biomass varied across cover crop species and locations. In 76-cm rows, interseeding earlier (V3) increased cover crop biomass production. The relative fitness of cover crops was greater than that of weeds in each combination of cultural practices that included narrow spacing (76 cm), whereas the relative fitness of weeds was greater than that of cover crops when interseeding in wide rows (152 cm). The effect of row spacing on corn yield varied among locations, with higher yields observed in 76-cm row spacing compared with 152-cm at two of three locations. Our results show that interseeding early (V3) on 76-cm row spacing can balance cover crop and corn production management goals, while placing cover crops at a relative fitness advantage over weeds.

Identification of stem rot of stock (Matthiola incana) caused by Sclerotinia sclerotiorum in China

The ornamental plant stock flower (Matthiola incana (L.) R. Br.) has been widely cultivated in China. In 2021, stem rot on M. incana, which caused plant death, was first observed in Shanghai, China. Field surveys indicated a disease incidence of 15%–20%. Following pathogen isolation, identification was performed by combining morphological observation of colonies, sclerotia and apothecia, with molecular methods, including DNA sequencing and phylogenetic analysis. Morphological characteristics of the isolates, including white cottony mycelium, blackish globular to irregularly shaped sclerotia and apothecia formation, were consistent with Sclerotinia sclerotiorum. Results of sequence comparison and phylogenetic analysis based on the internal transcribed spacer (ITS) sequences supported morphological data. Pathogenicity assays were conducted successfully according to Koch's postulates. Considering the results of the morphological and molecular identification, along with the pathogenicity assessment, S. sclerotiorum was confirmed as the causal agent of stem rot of stock flower in Shanghai, China. A combination of cultural practices, rotation of resistant ornamentals, and biological and chemical treatments is recommended to control stem rot of stock.

Evaluation of different weed management strategies including non‐chemical tools and cinmethylin for control of multiple herbicide‐resistant Alopecurus myosuroides

AbstractThe development of resistance in Alopecurus myosuroides populations to different herbicide active ingredients in Europe exacerbates efforts toward its chemical control. In Europe, cinmethylin provides an additional mode of action for the control of A. myosuroides. The objective of this study was to evaluate three resistance weed management (RWM) strategies, including cinmethylin and other pre‐emergence herbicides, for the control of multiple herbicide–resistant A. myosuroides. The RWM strategies used in this study differed in the extent of preventive cultural practices (tillage, crop rotation, sowing date and stale seedbed). Two field trials were conducted at sites with ACCase‐ and ALS‐resistant A. myosuroides biotypes in Germany between 2017 and 2020. Cinmethylin was included in the herbicide regime for A. myosuroides control. The combination of initial inversion tillage, delayed sowing, crop rotation diversification, and stale seedbed reduced the density of A. myosuroides bup to 90% compared to a strategy with pre‐emergence herbicides used as main components in control. At both sites, the amount of viable A. myosuroides seeds in the soil seed bank was reduced by over 90% after a 3‐year trial period in plots with initial inversion tillage. Molecular analyses revealed that the omission of ACCase and ALS inhibitors did not reduce the proportion of resistant A. myosuroides biotypes. Long‐term control of resistant A. myosuroides must be based on a combination of cultural practices that reduce the soil seed bank and suppress the occurrence of A. myosuroides and the use of still‐effective active ingredients for preventing the renewed entry of seeds into the soil.

Management of Banana Xanthomonas Wilt: Evidence from Impact of Adoption of Cultural Control Practices in Uganda

Banana Xanthomonas Wilt (BXW) is an important emerging and non-curable infectious plant pathogen in sub-Saharan Africa that can cause up to 100% yield loss, negatively impacting sustainable access to food and income to more than 100 million banana farmers. This study disentangles adopters into partial and full adopters to investigate the factors that are relevant to sustain the adoption process of BXW control practices and quantifies the impact of adopting the practices. Data from a randomly selected sample of 1200 banana farmers in Uganda where the disease is endemic was used. A multinomial logit model was used to determine the factors affecting adoption of control practices and augmented inverse probability weighting was employed to estimate the impacts of adoption on banana productivity and sales. Results show that training a woman farmer and having diverse sources of information about BXW control practices increased adoption of the control practices and reduced the disease incidences. Farmers who adopted all the recommended control practices achieved significantly the highest values of banana production and sales. We conclude that improving information access through farmers’ preferred communication channels, having women-inclusive trainings, and a combination of cultural practices are effective ways for sustaining adoption of the control practices.

Towards a better management of the gustatory quality of pineapple using the Simpiña crop model

Fruit quality has become increasingly important in fruit production, and improving the quality of products is an economic, public health, and scientific concern. The gustatory quality of fruit at harvest is affected by environmental conditions and management and can be highly variable. Our objective was to use the SIMPINA model, linked to SIMPINA - Sugar and SIMPINA - TA to identify combinations of cultural practices that optimize the gustatory quality of pineapple at harvest in the main areas of production on Reunion Island. SIM PINA - Sugar simulated total soluble solids (TSS) during fruit development. Titratable acidity (TA) was simulated with a statistical model linking periods during fruit development where climatic variables (rainfall, global radiation and temperature) affect TA of pineapple at harvest. The optimal sweetness index TSS/TA was used to select combinations of cultural practices that improve gustatory quality. Globally, to reach the optimal TSS/TA, the set of practices, e.g., optimum months for planting, dates of forcing, planting density and irrigation varied according to the diversity of climatic conditions in the main areas of production studied. Cultural practices selected lead to the production of large fruits (>700 g) and the model consistently identified harvest dates in the warm season as the time when the optimal TSS/TA was obtained regardless of area of production.

Comparative Genomics of Botrytis cinerea Strains with Differential Multi-Drug Resistance.

Botrytis cinerea is a ubiquitous fungus difficult to control because it possess a variety of attack modes, diverse hosts as inoculum sources, and it can survive as mycelia and/or conidia or for extended periods as sclerotia in crop debris. For these reasons the use of any single control measure is unlikely to succeed and a combination of cultural practices with the application of site-specific synthetic compounds provide the best protection for the crops (Williamson et al., 2007). However, the chemical control has been adversely affected by the development of fungicide resistance. The selection of resistant individuals in a fungal population subjected to selective pressure due to fungicides is an evolutionary mechanism that promotes advantageous genotypes (Walker et al., 2013). High levels of resistance to site-specific fungicides are commonly associated with point mutations. For example the mutations G143A, H272R, and F412S leading to changes in the target proteins CytB, SdhB, and Erg27 are conferring resistance of the pathogen to the chemical classes of QoIs, SDHIs, and hydroxyanilides, respectively (Leroux, 2007). Multidrug resistance is another mechanism associated with resistance in B. cinerea which involves mutations leading to overexpression of individual transporters such as ABC and MFS (Kretschmer et al., 2009). This mechanism is associated with low levels of resistance to multiple fungicides including the anilinopyrimidines and phenylpyrroles. However, a subdivision of gray mold populations was found to be more tolerant to these two classes of fungicides (Leroch et al., 2013). Previous reports have clearly demonstrated that the resistance to anilinopyrimidines has a qualitative, disruptive pattern, and is monogenically controlled (Chapeland et al., 1999). In order to elucidate the mechanism of the resistance, the whole genome of three different samples (gene pools) was sequenced, each containing DNA of 10 selected strains of the same genotype regarding resistance to seven different classes of fungicides including anilinopyrimidines. This report presents the publicly available genomic data.

Management of Soft Rot (Pythiumspp.) and Wilt (Ralstonia solanacearum) of Ginger (Zingiber officinale) in Andamans

Five isolates of Trichoderma and one isolate of Pseudomonas fluorescens were evaluated against Pythium and Ralstonia solanacearum in vitro and in vivo with different combinations with some chemical fungicides and neem cake. The results indicated that all isolates of Trichoderma, lone isolates of Pseudomonas fluorescens and fungicides alone significantly inhibited both pathogens in vitro. The biocontrol agent, Trichoderma spp and isolate of Pseudomonas fluorescens were comparable to each other in their ability to inhibit both the pathogens. The combination of cultural practices, chemical pesticides at low concentration, biocontrol agents with optimum population (cfu/g) along with neem cake have been found most effective in reducing the disease incidence of both soft rot and wilt of ginger and corresponding yield increase in the year 2008–09 and 2009–10. Furthermore, seed + soil application of biofungicides and chemical fungicides resulted into lowest incidences of soft rot and wilt diseases, highest rhizosphere population of biocontrol agents at all the dates observed and highest yield of ginger.

Which cropping systems to reconcile weed-related biodiversity and crop production in arable crops? An approach with simulation-based indicators

Weed management must both control weed harmfulness for crop production and promote weed contribution to biodiversity as an essential component of biodiversity in agricultural landscapes. The objective of the present paper was to evaluate a large range of existing cropping systems to determine management rules for reconciling weed-related biodiversity and weed harmfulness, comparing 26 contrasting cropping systems identified via farm surveys in two contrasting French regions, Burgundy and Poitou-Charentes. These systems were simulated, using the weed dynamics model FlorSys which predicts weed flora dynamics over the years, depending on cropping system and pedoclimate. The simulated flora was translated into five weed harmfulness indicators (crop yield loss, harvest contamination, harvesting difficulty, field infestation, additional crop disease due to weeds) and five weed-related biodiversity indicators (weed species richness and equitability, weed-based trophic offer for birds, insects and pollinators). Cropping system performance was assessed with a Principal Component Analysis (PCA) on the 10 weed-impact indicators, followed by a hierarchical clustering analysis. Five contrasting profiles in terms of weed harmfulness and contribution to biodiversity were identified, combining different levels of weed harmfulness and biodiversity. To identify management strategies (i.e., combinations of cultural practices) for reaching these different performance profiles, tree-based regression and classification models (CART) were constructed to explain performance profiles as a function of cropping system descriptors and pedoclimatic variables. Ten management strategies were identified for reaching the five performance profiles. The most interesting performance profile, which minimized all harmfulness indicators (except harvest contamination and harvesting difficulty) and maximized all biodiversity indicators (except species richness), was reached by a single strategy type, consisting of low or no-till systems. Systems with cover crops and little or no mechanical weeding also reconciled most production and biodiversity goals. Multiple management pathways for reaching a given goal present the advantage of letting farmers choose the strategy most compatible with the objectives and constraints of their farm. The present results were obtained with annual weed species only, and taking into account the management of perennial weeds will probably modify the strategies. The same method was also applied to identify strategies for reconciling crop production, biodiversity and reduced herbicide use, though none of the investigated cropping systems was able to reconcile all three objectives, indicating that novel cropping systems must be designed specifically for this objective.

First Report of Penicillium expansum Isolates Resistant to Pyrimethanil from Stored Apple Fruit in Pennsylvania

Apples in the United States are stored in low-temperature controlled atmospheres for 9 to 12 months and are highly susceptible to blue mold decay. Penicillium spp. cause significant economic losses worldwide and produce mycotoxins that contaminate processed apple products. Blue mold is managed by a combination of cultural practices and the application of fungicides. In 2004, a new postharvest fungicide, pyrimethanil (Penbotec 400 SC, Janseen PMP, Beerse, Belgium) was registered for use in the United States to control blue mold on pome fruits (1). In this study, 10 blue mold symptomatic 'Red Delicious' apples were collected in May 2011 from wooden bins at a commercial facility located in Pennsylvania. These fruit had been treated with Penbotec prior to controlled atmosphere storage. Ten single-spore Penicillium spp. isolates were analyzed for growth using 96-well microtiter plates containing Richards minimal medium amended with a range of technical grade pyrimethanil from 0 to 500 μg/ml. Conidial suspensions adjusted to 1 × 105 conidia/ml were added to three 96-well plates for each experiment; all experiments were repeated three times. Nine resistant isolates had prolific mycelial growth at 500 μg/ml, which is 1,000 times the discriminatory dose that inhibited baseline sensitive P. expansum isolates from Washington State (1). However, one isolate (R13) had limited conidial germination and no mycelial proliferation at 0.5 μg/ml and was categorized as sensitive. One resistant (R22) and one sensitive (R13) isolate were selected on the basis of their different sensitivities to pyrimethanil. Both isolates were identified as P. expansum via conventional PCR using β-tubulin gene-specific primers according to Sholberg et al. (2). Analysis of the 2X consensus amplicon sequences from R13 and R22 matched perfectly (100% identity and 0.0 E value) with other P. expansum accessions in GenBank including JN872743.1, which was isolated from decayed apple fruit from Washington State. To determine if pyrimethanil applied at the labeled rate of 500 μg/ml would control R13 or R22 in vivo, organic 'Gala' apple fruit were wounded, inoculated with 50 μl of a conidial suspension (1 × 104 conidia/ml) of either isolate, dipped in Penbotec fungicide or sterile water, and stored at 25°C for 7 days. Twenty fruit composed a replicate within a treatment and the experiment was performed twice. Non-inoculated water-only controls were symptomless, while water-dipped inoculated fruit had 100% decay with mean lesion diameters of 36.8 ± 2.68 mm for R22 and 38.5 ± 2.61 mm for R13. The R22 isolate caused 30% decay with 21.6 ± 5.44 mm lesions when inoculated onto Penbotec-treated apples, while the R13 isolate had 7.5% decay incidence with mean lesion diameters of 23.1 ± 3.41 mm. The results from this study demonstrate that P. expansum pyrimethanil-resistant strains are virulent on Penbotec-treated apple fruit and have the potential to manifest in decay during storage. To the best of our knowledge, this is the first report of pyrimethanil resistance in P. expansum from Pennsylvania, a major apple growing region for the United States. Moreover, these results illuminate the need to develop additional chemical, cultural, and biological methods to control this fungus.

First the Revolutionary Culture

The long-standing marginalization of highland Peru, coupled with the terrible violence of the 1980s and 1990s civil war, make it a difficult place for political mobilization. Nevertheless, one village successfully asserted its self-determination in the face of an exploitative political economy through conversion to Evangelical Christianity. A revolutionary cultural break from the mainstream created a vibrant local subculture that stressed brotherhood and provided meaning to adherents, allowing them to seize local opportunities to assert a more egalitarian social reality. While specific to this village’s conditions, these experiences speak to broader possibilities for innovative social change through novel combinations of cultural practices and political concerns.La marginalizacion de larga data del altiplano peruano, junto con la terrible violencia de la guerra civil de las decadas de 1980 y 1990, dificulta la movilizacion politica. Sin embargo, un pueblo hizo valer exitosamente su auto-determinacion fren...

Beyond the Basics: The Evolution and Development of Human Emotions

The suggestion that at least some emotions are modular captures a number of our intuitions about emotions: they are generally fast responses to a stimulus, they are involuntary, and they are easily distinguished (at least in most cases) from one another; we simply know that, for example, anger feels different than fear. Candidates for modular emotions are usually the so-called “basic” emotions - anger and fear are good examples of these. Defenders of emotion theories that focus on basic emotions, such as Paul Ekman in psychology and Paul Griffiths in philosophy, emphasize the advantages of theories that stress the evolutionary continuity of emotional expression and link emotions to the activity of neural circuits that are similar in human beings and other animals.In this paper, however, I will examine arguments for the discontinuity of emotions in human beings, as compared with other animals. Owing to a combination of cultural practices and neuroanatomy, both our emotional “wiring” and our emotions are unique.

Incidence of natural enemies of Planococcoides njalensis Laing and Planococcus citri Risso in researcher-managed and farmer-managed cocoa farms

Studies were carried out at Tafo in researcher (CRIG)-managed farms and farmer-managed farms to assess the incidence of natural enemies in colonies of Planococcoides njalensis Laing and Planococcus citri Risso, the two most important vectors of the Cocoa Swollen Shoot Virus disease in Ghana. The CRIG farms were sprayed four times with either lindane or propoxur per mirid season, using motorised knapsack sprayers, and weeded at least twice annually, mostly by slashing with cutlass and occasionally by applying herbicides. Control of black pod disease caused by Phytophthora palmivora (Butl.) Butl. was by a combination of cultural practices and chemical control. The peasant farmers partially adopted the CRIG recommendations, spraying unspecified dosages of any available insecticides once or twice annually against mirids, and rarely spraying against the black pod disease. Most weeded once or twice annually while others waited till harvesting time, only to make tracks to trees carrying ripped pods. Mealybug colonies were sampled monthly in both farm types by examining cocoa trees from the base to hand height, brushing observed colonies within this range into glass vials and taking them to the laboratory. Unparasitized adults (females), third instar nymphs and mummies were separated and counted to give an estimate of the colony size. Mummies were kept in vials and observed for the emergence of parasitoids. The monthly incidence of both P. njalensis and P. citri colonies on the farmers' farms and the CRIG farms did not differ significantly. Similarly, the percentages of their colonies free from natural enemies in the two farm types did not differ significantly, and the differences in the incidence of parasitoids, and also of predators, in colonies of the two vectors in the two farm types were not significant. These results are discussed in terms of agrochemical usage and the efficiency of the natural enemies in the control of mealybug vectors of CSSV. (Journal of the Ghana Science Association: 2001 3(3): 45-51)

Management of wheat and barley root diseases in modern farming systems

Root diseases, namely take-all and Rhizoctonia, Pythium and Fusarium root rots, are so widespread and occur so uniformly within fields of wheat and barley in the U.S. Pacific Northwest (PNW) that we have come to accept these crops with these diseases as normal ‘healthy’ crops. The main reasons for the expanding range and increasing prevalence of root diseases on wheat and barley in this and many other cereal-growing areas of the world are two-fold: increased frequency of cereals in the rotation and the use of less, or no, tillage. Both trends are here to stay because of their economic advantages and environmental benefits. Managing these diseases in these modern farming systems is no small challenge since, unlike most leaf diseases of these crops, all cultivars of wheat and barley are more or less equally susceptible to all four root diseases. Through a combination of cultural practices, the severity of these diseases can at least be limited to ‘chronic’, while ‘acute’ outbreaks or what growers call ‘wrecks’, are relatively rare. These practices are timely and effective management of volunteer and grass weed hosts before planting; placement of fertiliser, especially phosphorus, beneath the seed within easy access of diseased roots; soil disturbance below the seed; trash removal from within the seed row; pairing the row for a more open canopy to favour warming and drying of soil beneath the crop residue; and the use of fresh seed and treatment of the seed with a combination of fungicides for improved seedling vigour. No equivalent effort has been made in any other crop to manage a disease complex without the benefit of host plant resistance. In spite of this, these practices, together with take-all decline, only elevate yields to about 80% of the potential as revealed by fumigated (methyl bromide) check plots. Future research must concentrate on the development of host plant resistance, including host plant resistance with transgenes.

Managing fungal diseases of potato

Potato, Solatium tuberosum, is the fourth-ranked food crop used to support a growing world population because of cultivar versatility and high complex carbohydrate content. Potatoes can be stored for long periods for table and processing markets, but are plagued by storage disease problems. Diseases both in the field and during storage can be limiting factors in sustainable and profitable potato production wherever they are grown. In North America, many diseases caused by fungi are important and require a variety of management practices to reduce them to tolerable economic levels. Such diseases include late blight [Phytophthora infestans], silver scurf [Helminthosporium solani], pink rot [Phytophthora erythroseptica], dry rot [Fusarium sambucinum], verticillium wilt [Verticillium dahliae and Verticillium albo-atrum], black scurf [Rhizoctonia solani], and early blight [Alternaria solani]. These diseases have both a field and storage component, and disease management inputs may be necessary throughout the season for disease control. A continuing combination of cultural practices, planting of resistant cultivars, clean seed, crop rotation, and fungicides (plant medicines) are necessary for disease control. This presentation highlights the basics of each disease and, based on disease epidemiology, the current strategies used for control, and strategies underway for future control, including the development of resistant cultivars.

Effects of Managing Citrus Red Mite (Acari: Tetranychidae) and Cultural Practices on Total Yield, Fruit Size, and Crop Value of 'Navel' Orange

The value of suppressing spring populations of the citrus red mite, Panonychus citn McGregor, at or below the conventional treatment threshold of two adult females per leaf was determined on ‘Navel’ orange, Citrus sinensis (L.) Osbeck, in the San Joaquin Valley. Mites on untreated trees reached peak populations between five and eight adult females per leaf. These higher mite populations caused significant reductions (∼10%) in yield in only one of three studies. Average fruit size per tree increased with increasing mite-days in all three studies. Fertilization level was the only cultural practice to consistently affect total fruit yield, and yield increased with increasing fertilization level. Increasing irrigation levels also increased fruit size. The rate of fruit ripening was accelerated with increasing fertilization level and delayed by the application of a growth regulator to delay rind senescence. In general, total yield per tree and average fruit size did not differ significantly due to interactions between acaricide treatments and the 36 other combinations of cultural practices. On average, large fruit are more valuable than small fruit, although there is substantial variation in price structure among seasons. Therefore, the slight increases in average fruit size on acaricide-untreated trees compensated economically for slight reductions in total yield. The economic benefit of suppressing citrus red mite populations in these studies depended greatly upon the price structure in effect when the crop was harvested and sold 7-11 mo after treatment decisions had to be made. Often, the increase in crop value did not offset the cost of acaricide application.

Insect pests of millets and their management: A review

Abstract About a hundred insect pests attack millets in the field and during storage. Some are common throughout the millet growing areas. Stem borers and grain midge are of regular occurrence. White grubs are important in India. Spike worms have recently become serious in the sub‐Sahelian zone of West Africa. Sporadic attacks of blister beetles, armyworms, grasshoppers, chinch bugs, leaf beetles, head caterpillars and head bugs result in severe yield losses in certain seasons. There is a higher incidence of storage pests in the rainy season. Research on pest management needs to be intensified. The tactics differ with the pest complex and the agroecosystem. However, a combination of cultural practices and resistant cultivars have proved to be effective. Multiple pest resistance has become more important in order to reduce insecticide use, common in pest endemic areas and during outbreaks. The exchange of genetic material and research information can provide an interdisciplinary approach to pest management...