Cultural Management Techniques Research Articles

Cultural control methods improve management of leafhopper vector of X-disease

X-disease, caused by the phytoplasma ‘Candidatus Phytoplasma pruni’, is currently threatening Pacific Northwest (USA) stone fruit (Prunus) production, particularly sweet cherry (P. avium). There is no cure, and infected fruit remain unmarketable throughout the tree's life. Management efforts focus on reducing transmission through infected tree removal and frequent chemical applications to control the leafhopper vectors. The increase in chemical inputs has broken down stone fruit integrated pest management techniques and is neither economically nor environmentally sustainable. To investigate sustainable vector management, we assessed the efficacy of two long-lasting cultural management techniques, kaolin clay (Surround WP) and reflective plastic geotextile (Extenday), to deter leafhoppers from trees and prevent population growth within orchards. These methods were tested against untreated control plots in Washington State commercial stone fruit blocks in 2021 and 2022. Colladonus montanus reductus (Van Duzee) was the most abundant leafhopper vector species captured in both years. In cherry blocks, Extenday consistently reduced C. m. reductus densities by 80–90%, while kaolin clay caused a 45–50% reduction in leafhoppers, but only when they were abundant (more than 10 leafhoppers per trap). Sticky cards placed at varying heights revealed that kaolin clay caused C. m. reductus to be proportionally more abundant near the ground cover than in the tree canopy regardless of overall population density. The combination of reducing C. m. reductus density and shifting their distribution into the ground cover demonstrates both plastic geotextiles and kaolin clay provide effective post-harvest strategies for X-disease vector management.

Changes in Agronomic, Antioxidant Compounds, and Morphology Parameters of Green and Red Lettuces (Lactuca sativa L.) by Successive Harvests and UV-B Supplementation

The growing demand for lettuce has prompted the need for higher quality standards. Consequently, researchers have focused their efforts on identifying cultural management strategies that can enhance the synthesis of antioxidant compounds, leading to improved functional properties of lettuce. In this regard, two experiments were conducted on hydroponically grown Lollo Bionda ‘Levistro’ and Lollo Rosso ‘Carmoli’ lettuces, known, respectively, for their green and red crispy leaves. The first experiment assessed the effects of harvest time and cutting on fresh weight (FW), dry weight (DW), total phenolic content (TPC), total flavonoid content (TFC), total anthocyanin content (TAC), and antioxidant capacity (AC). The second experiment evaluated the response of FW, DW, TPC, TFC, TAC, AC, proline content, and morphological cell changes to UV-B supplementation in greenhouse conditions as well as the impact of successive harvests on the same plant. UV-B radiation and cutting led to a reduction in FW, but they also showed an increase in DW. Furthermore, UV-B radiation, cutting, and plant growth stage had significant effects on TPC, TFC, and AC in both cultivars. Applying 10.5 kJ m−2 of UV-B radiation or performing different harvests resulted in increased TFC in ‘Levistro’, exhibiting a remarkable 91% increase at the third harvest compared to the control group (0 kJ m−2 at the first harvest). UV-B radiation also induced changes in anatomical cell distribution in both cultivars, leading to a 37% increase in intracellular space in ‘Levistro’ and a reduction of up to 8.2% in ‘Carmoli’. Lastly, at a later stage of plant development (9-10th true leaves), ‘Carmoli’ demonstrated a 51% increase in TPC, 95% in TFC, and 65% in TAC, highlighting its potential as an intriguing strategy to obtain lettuce varieties with higher antioxidant properties. These findings underscore the significance of implementing cultural management techniques to enhance the antioxidant composition of lettuce.

Farmers Perceptions on the Use of Insecticides For Management of Brinjal Shoot and Fruit Borer

The survey was conducted in Chattogram, Jashore and Mymensingh regions of Bangladesh to find out the farmers’ knowledge and perceptions about insecticide usages in brinjal for management of brinjal shoot and fruit borer (BSFB) during August 2014 to April 2015. All the farmers of three different study areas reported that BSFB is a major problem and needs to be controlled. On an average, 91.68% farmers used conventional chemical method as main protection technique by using only insecticide whereas only 5.54% farmers used IPM method and 2.78% used different types of cultural pest management techniques for controlling BSFB. On an average, 40.80% farmers used insecticide as single form and 59.20% farmers used it in the form of cocktail. During three and half months crop season 36.35 to 57.33 times spray can occur depending on the regions. On an average, 73.23% farmers followed the advice of pesticide dealers in selecting pesticides and their doses for spraying against BSFB. Only 7.69% farmers followed the advice of extension workers which is much less as compared to the pesticide dealers. On an average, 73.98% farmers reported that insecticide was applied without any protection measures.
 Bangladesh J. Agril. Res. 46(4): 457-468, December 2021

Common Tomato High Tunnel Production Diseases in Florida

This new 7-page article provides a concise overview of some influential high-tunnel tomato soilborne and foliar diseases and their cultural management techniques. Written by Zachary D. Eldred, Shufang Tian, Gary E. Vallad, Xin Zhao, Mathews Paret, and Nicholas S. Dufault and published by the UF/IFAS Plant Pathology Department.https://edis.ifas.ufl.edu/pp368

Agro-ecological factors influencing geographic distribution and epidemic development of hot pepper wilt complex disease in Northwestern Ethiopia

Hot pepper (Capsicum annuum L.) production is seriously affected by the wilt complex disease. A study was executed in Northwestern Ethiopia during the 2020 and 2021 main cropping seasons to assess the geographic distribution of the hot pepper wilt complex disease and the association of agro-ecological factors influencing epidemic development. In total, 304 fields were assessed in 11 districts and four zones. The associations among disease variables and biophysical factors were determined using logistic regression analyses. Major pathogens associated with wilt complex disease that exhibited 100% occurrence in all the surveyed districts were Fusarium oxysporum f.sp. capsici, F. solani and Rhizoctonia solani. Out of the 304 hot pepper fields assessed, 233 fields (76.6%) were affected by the wilt complex disease. The highest mean disease incidence (72.4%) and severity (70.1%) were recorded in the Jabi Tehena district, while the lowest incidence (17.1%) and severity (14.9%) were recorded in the Guagusa Shekudad district. District, year, altitude, plant growth stage, weeding frequency, previous crop, wilt management practice, cropping system, and disease-aggravating factor revealed highly significant (p < 0.001) associations with disease incidence and severity. These predictor variables influenced the disease development either positively or negatively in the surveyed areas. The high (≥50%) incidence and severity of wilt complex disease in hot pepper were positively and strongly associated with Bure, Dembecha, Jabi Tehena and Wenberma districts in the 2020 cropping season, where the altitude was <2000 m a.s.l., wilting began at the seedling growth stage, weeding frequency was 1–3 times, and the previous crop was a vegetable. Hence, proper crop husbandry practices and cultural wilt management techniques should be employed by growers to minimize wilt complex disease epidemic development and to sustain hot pepper production and productivity in the survey areas and other locations with similar agro-ecologies.

Occurrence of Mummy Berry Associated with Huckleberry (Vaccinium membranaceum) Caused by Monilinia spp. in Oregon.

In this Short Communication we describe the occurrence of mummy berry associated with huckleberry (Vaccinium membranaceum) caused by Monilinia spp. in Oregon. To our knowledge, this is the first report of a Monilinia spp. associated with mummy berry of huckleberry in Oregon. Sequence data from our specimens reveal the closest identity was Monilinia vaccinii-corymbosi, a pathogen of commercial blueberry (Vaccinium corymbosum). This may be a new species of Monilinia, not previously reported on huckleberry, and further investigation is needed. Of specific importance, the huckleberry holds cultural importance as a sacred First Food of the Confederated Tribes of the Umatilla Indian Reservation and other Pacific Northwest tribes. Although plant pathogen management in natural landscapes presents unique challenges, we will work with tribal authorities to determine whether cultural management techniques may mitigate yield loss due to Monilinia spp.

An Overview of the Pepper Weevil (Coleoptera: Curculionidae) as a Pest of Greenhouse Peppers

Abstract The pepper weevil (Anthonomus eugenii Cano) is a destructive insect pest of field and greenhouse pepper crops across North America. Its management remains challenging with significant implications for pepper production, despite a documented presence in Central America, Mexico, the United States, and the Caribbean for approximately a century, and recently in Canada. Currently, the main tools and methods applied to manage pepper weevil populations in greenhouse peppers are the implementation of strict biosecurity protocols, diligent monitoring, physical and cultural management techniques, and chemical insecticides when necessary. However, these tools can be costly, labor-intensive, and insufficient, particularly when new outbreaks go undetected for prolonged periods. Additionally, the use of available insecticides is limited due to significant nontarget effects these have on biological control agents used to manage other important greenhouse pepper pests. Recently, research efforts have focused on developing better tools for pepper weevil management to mitigate a rising incidence of insecticide resistance and the spread of weevils into temperate regions, however, multiple constraints remain. Here, we review the current state of knowledge of the pepper weevil and identify information gaps, which future research should address to improve the targeted management of this pest in greenhouse pepper production systems.

Soil rock fragment is stronger driver of spatio-temporal soil water dynamics and efficiency of water use than cultural management in holm oak plantations

Water is the main component in the conservation and functioning of Mediterranean ecosystems. There is a trade-off between plant water use during establishment and soil water conservation. Rock fragments and cultural management are two key factors affecting soil water dynamics on forest establishment. In this work, we studied the interactions of different cultural management techniques (tillage, herbicide and mulching) with soil rock fragment content (soil gravel) and their effects on the spatio-temporal water dynamics and efficiency of water use in Mediterranean forest plantations. Soil water content (SWC, l/m3), soil water depletion rate (k) and water use efficiency (WUE, μmol CO2/mol H2O) were monitored along a two-year period in a holm oak reforestation. The results show that SWC and its spatio-temporal dynamics were defined by a significant interaction between the cultural management techniques and the rock fragment content. Cultural management techniques had weak effects on SWC when compared to the control treatment, although significant differences were found. The soil rock fragment content accounted for most of the variability in SWC; and soils with a content below 5% had higher water contents. The cultural treatments showed some influence on water behaviour under SWC more limited conditions, that is, when rock fragment contents was higher than 15% and/or in summer periods. Finally, SWC was also a limiting factor for the WUE of holm oak seedlings, being the WUE values higher when the soil water supply was more restricted. The maximum WUE was reached at a rock fragment content in the soil profile of 17%, combined with mulch treatment, during dry summer conditions. Thus, the interaction between the rock fragment content and cultural management is a key element in trade-offs between water conservation and plant water-use objectives in Mediterranean forest restoration strategies.

Examining Host Selection by Mexican Bean Beetle (Coleoptera: Coccinellidae) Using Mark-Release-Recapture.

Mexican bean beetle, Epilachna varivestis Mulsant, is a pest of snap bean and lima bean in the eastern United States. This pest is susceptible to many insecticides available to conventional growers; however, organic management using parasitoid releases and organic insecticides have inconsistent results. In the interest of developing cultural management techniques such as trap crops or push–pull systems, five bean cultivars were evaluated for preferential host selection by E. varivestis using marked beetles in field cages and open plots. Beetles were marked with a water-based paint pen and their locations on plants monitored over time. In field cages, the purple wax bean, Dragon’s Tongue (DT), was preferred over yellow wax, green bean and lima bean; soybean was the least preferred overall. Recaptures of E. varivestis adults in open field plots progressively decreased following beetle release, suggesting the affinity of adults to disperse despite being on or near acceptable hosts. The two wax beans were equally preferred in open field experiments, partially more than the green and lima bean and consistently more than the soybean. These experiments suggest that DT may be a suitable crop for trap cropping or attract and kill strategies for E. varivestis.

Effects of renewal time, taproot cutting, ploughing practice, false seedbed and companion crop on docks (Rumex spp.) when renewing grassland

Docks (Rumex spp.) are a considerable problem in grassland production worldwide. We investigated how different cultural management techniques affected dock populations during grassland renewal: (I) renewal time, (II) companion crop, (III) false seedbed, (IV) taproot cutting (V), plough skimmer and (VI) ploughing depth. Three factorial split-split plot experiments were carried out in Norway in 2007–2008 (three locations), 2008–2009 (one location) and 2009 (one location). After grassland renewal, more dock plants emerged from seeds than from roots. Summer renewal resulted in more dock seed and root plants than spring renewal. Adding a spring barley companion crop to the grassland crop often reduced dock density and biomass. A false seedbed resulted in 71% fewer dock seed plants following summer renewal, but tended to increase the number of dock plants after spring renewal. In some instances, taproot cutting resulted in less dock biomass, but the effect was weak and inconsistent, and if ploughing was shallow (16 cm) or omitted, it instead increased dock root plant emergence. Fewer root plants emerged after deep ploughing (24 cm) compared to shallow ploughing, and a plough skimmer tended to reduce the number further. We conclude that a competitive companion crop can assist in controlling both dock seed and root plants, but it is more important that the renewal time is favourable to the main crop. Taproot cutting in conjunction with ploughing is not an effective way to reduce dock root plants, but ploughing is more effective if it is deep and a skimmer is used.

Comparative Water and Nutrient Application Rates among Ornamental Operations in Maryland

Quantifying the range of fertilizer and irrigation application rates applied by the ornamental nursery and greenhouse industry is challenging as a result of the variety of species, production systems, and cultural management techniques that are used. To gain a better understanding of nutrient and water use by the ornamental industry in Maryland, 491 potential operations (including multiple addresses and contacts) in the state were mailed a packet of information asking for their voluntary participation. Of the 491 potential operations, it was determined that 348 operations were currently in operation. Of those 348 operations, 48 (14% of the operations in the state) participated in a site visit and an in-depth interview, and a detailed site analysis of the water and nutrient management practices was performed on a production management unit (MU) basis. The authors define an MU as a group of plants that is managed similarly, particularly in regard to nutrient and irrigation application. Greenhouse operations reported, on average, 198, 122, and 196 kg/ha/year of nitrogen (N), phosphorus (P, as P2O5), and potassium (K, as K2O) fertilizer used, respectively, for 27 operations, representing 188 MUs. Twenty-seven outdoor container nursery operations had a total of 162 MUs, with an average of 964, 390, and 556 kg/ha/year of N, P2O5, and K2O fertilizer used, respectively. Field nursery (soil-based) operations were represented by 17 operations, producing 96 MUs, with an average of 67, 20, and 25 kg/ha/year of N, P2O5, and K2O fertilizer used, respectively. Irrigation volume per application was greatest in container nursery operations, followed by greenhouse and field nursery operations. Data were also analyzed by creating quartiles, which represent the median of the lowest 25%, the middle 50%, and highest 75% of values. It is likely that the greatest quartile application rates reported by growers could be substantially reduced with little to no effect on plant production time or quality. These data also provide baseline information to determine changes in fertilization practices over time. They were also used as inputs for water and nutrient management models developed as part of this study. These data may also be useful for informing nutrient application rates used in the Chesapeake Bay nutrient modeling process.

Disease Progression and Productivity of Melon Plants with Different Cultural Management Techniques

Studies of several agricultural crops have been concluded with the aim of achieving greater environmental balance by reducing the use of pesticides, as well as promoting the viability of cultural management techniques that diminish the proliferation of phytopathogens. In the melon growing industry, studies of this sort are scarce. Therefore, the objective of this work was to evaluate the influence on disease progression and melon crop productivity of various production systems, including fertilization, spacing, pesticide use, and pruning of branches and culling of fruits. Organic fertilization was efficient for the management of phytopathogens due to the presence of antagonistic microorganisms. Minimizing pesticide use did not affect crop productivity.

English

Fusarium blight of soybean, caused by Fusarium oxysporum is one of the most destructive diseases of the legume. The pathogen is difficult to control owing to its persistence in the soil and wide host range. Soil tillage practice is one of the most important components of cultural soil management techniques that have a great influence on intensity of plant diseases. This study investigated the effect of tillage practice on the severity of Fusarium blight and yield of soybean. The land used for the trial was artificially inoculated with inoculum suspension of F. oxysporum left for one week before tillage. The experiment was laid out in a randomized complete block design (RCBD) with four treatments, each replicated three times. The treatments consist of ploughing only (P), ploughing followed by harrowing (PH), harrowing only (H) and no tillage (control). The parameters assessed include disease severity, number of pods per plant, pod length, pod weight, 100 seed weight and total seed yield. Findings from this study showed that at 4 weeks after planting, the highest disease severity (1.9) was recorded in soybean planted on ploughed land while the least blight severity (0.8) was recorded with no tillage. Soybean sown under no tillage produced significantly (P<0.05) higher number of pods per plant (41.6) while the lowest pod number (23.3) were produced on soybean sown on ploughed land. Soybean sown under no tillage produced a significantly (P<0.05) higher seed yield (328.0 kg/ha) than all other treatments. Tillage practice is an effective way of managing soybean diseases owing to its potential to adjust soil temperature and moisture. The tillage methods used in the current study incorporated Fusarium blight pathogen at varying soil depths, with no tillage being the most effective approach of reducing the severity of soybean Fusarium blight in infected soil. Key words: Blight, Fusarium oxysporum, soybean, tillage, disease severity, yield.

Effect of the duration of inoculum exposure on development of citrus canker symptoms on seedlings of Swingle citrumelo

Citrus canker (Xanthomonas citri subsp. citri, Xcc) is one of the most serious diseases citrus in Florida, and elsewhere in the world. The disease causes yield loss and some fresh fruit trade restrictions may apply. Cultural management techniques such as windbreaks may work by not only reducing wind speed, but also reducing the period of exposure of susceptible foliage or fruit to those wind speeds that support infection from incoming inoculum. To investigate the effect of exposure period to inoculum of Xcc, seedlings of canker-susceptible Swingle citrumelo were exposed to sprayed inoculum for increasing periods at different wind speeds. The incidence and severity of citrus canker was assessed. In three experiments the incidence and severity of citrus canker most often increased with longer periods of exposure to inoculum, especially so at wind speeds of ≥16 m/s compared to wind speeds of ≤5 m/s (wind speed also increased disease incidence and severity). Regression analysis demonstrated relationships between period of exposure to inoculum and the percent infected leaves per plant, the number of lesions per plant, the number of lesions per infected leaf, and for the percent of infected leaves with lesions on the petioles at wind speeds of ≥16 m/s (R2 = 0.16–0.72). Due to the effect of inoculum exposure period and wind speed, attempts should be made to minimize exposure of canker-susceptible citrus when wind speed is highest and inoculum is available. Windbreaks should help minimize periods of exposure to splashed inoculum in high winds.

Modeling fruit ripening for improving peach homogeneity in planta

The combined use of a modeling system (PlantToon®) and of an innovative vis-NIR device (DA-Meter) was tested in peach. The first allows to design the tree structure and the fruit position on the tree while the DA-Meter was used to characterize non destructively the fruit ripening in planta. This instrument provides an index (IAD), that expresses the ripening stage reached by the fruit which correlates with chlorophyll content and ethylene emission to accurately describe the fruit ripening evolution. Combining the PlantToon® software with the DA-Meter data allows to virtually design the tree structure, to follow the fruit ripening along the season and also to determine the level of fruit heterogeneity in the field. These information can be used not only to establish the best moment to perform the harvest but also to tune up the cultural management techniques (e.g. fruit thinning and winter and summer pruning) to reduce the outliers fruit and to concentrate ripening to improve harvest and post-harvest management.

Pepper Veinal Mottle Virus, a Potyvirus of Pepper Under Tropical Conditions

Pepper veinal mottle virus (PVMV), a potyvirus causing disease in pepper, contributes to low yield, reduced fruit quality, and economic loss. Strains of the virus were identified and characterized, and the disease incidence, severity, and aphid vector distribution across agro-ecological zones were studied. Insecticide application and removal of infected plants are usually inadequate in reducing virus spread. Cultural management techniques including the use of organic manures, intercropping with tall companion crops, manipulation of date of planting, and use of tolerant/resistant varieties are effective to varying degrees. Integrating two or three techniques for management of PVMV is effective.

Review: The recruitment biology and ecology of large and small crabgrass in turfgrass: Implications for management in the context of a cosmetic pesticide ban

Turner, F. A., Jordan, K. S. and Van Acker, R. C. 2012. Review: The recruitment biology and ecology of large and small crabgrass in turfgrass: Implications for management in the context of a cosmetic pesticide ban. Can. J. Plant Sci. 92: 829–845. Large and small crabgrass (Digitaria sanguinalis and Digitaria ischaemum, respectively) are problem weeds within turfgrass. As seedling recruitment shapes the demography of annual weeds, it is important to assess the recruitment biology and ecology of crabgrass species to determine how these aspects may be impacted by various management techniques. This, in addition to an assessment of large and small crabgrass’ response to cultural management techniques in turfgrass, is the objective of this review. Turfgrass management either directly or indirectly affects the crabgrass recruitment microclimate by impacting the soil, topography, resources or plant cover, which in turn affects the degree and timing of crabgrass recruitment. Due to the increasing number and scale of cosmetic use pesticide bans in Canada this topic is particularly relevant. Crabgrass experiences a dormancy period of several weeks prior to being able to germinate. Microsite conditions of temperature and moisture have the greatest influence on dormancy breaking and germination; however, other factors such as light have shown some effect on recruitment. There is also evidence that factors such as seed scarification or treatment with nitrogenous compounds can increase recruitment. In turfgrass, common cultural practices, such as mowing, irrigation, and fertilization, can affect the recruitment of crabgrass. By pairing knowledge of the effects of microsite conditions on crabgrass recruitment with management that favours turfgrass vigour, better management practices to deter crabgrass infestation can be recommended. There are large gaps in research pertaining to the effects of cultural management techniques on crabgrass recruitment. Research to date has failed to make critical links between knowledge of these species’ recruitment biology and ecology and how this is affected or can be applied through herbicide alternative management. This review recommends that regional assessments of crabgrass populations are necessary to determine the most appropriate management strategies. This type of research would have the potential to guide ideal application timings for existing and developing alternative herbicides as well as recommendations for the best cultural management practices to deter crabgrass infestation in turf.

Incidence and epidemiology of Pepper veinal mottle virus (PVMV), a Potyvirus disease of pepper

There have been various reports about the devastating effect of Pepper veinal mottle virus (PVMV), a Potyvirus disease of pepper in Nigeria contributing to its low yield and reduced fruit quality leading to great economic loss. Different strains of the virus have been identified and characterised over the years and the disease incidence, severity and aphid vector distribution across agro-ecological zones studied. Different cultural management techniques have been tried and found to be effective with varying degree of success, and these included the use of organic manures, intercropping with tall companion crops, time and date of planting and the use of tolerant/resistant varieties. Integrated pest management techniques for PVMV disease have been found to be very effective.

The cultural transformation of large Chinese enterprises into internationally competitive corporations: case studies of Haier and Huawei

The Chinese government has recently introduced a policy requiring all large Chinese business corporations to transform their corporate cultures with the aim of increasing their competitiveness on the international stage. This paper traces the origins of the policy to the outstanding performance of a small number of Chinese firms since the late 1980s, a phenomenon attributed by the CEOs of these firms to effective implementation of cultural values change among their workforces. We give detailed accounts of two such firms, Haier Group and Huawei Technologies, demonstrating how they have utilized cultural management techniques to improve their employees’ performance. We also identify some negative aspects of their approach to cultural management that may impede these firms in their efforts to become truly international corporations.

Fungal diseases in forest nurseries in Finland

Norway spruce (Picea abies), Scots pine (Pinus sylvestris) and silver birch (Betula pendula) are the major tree species grown in Finnish forest nurseries where 99% of the seedlings are grown in containers first in plastic-covered greenhouses and later outdoors. The main diseases on conifer seedlings are Scleroderris canker (Gremmeniella abietina), Sirococcus blight and cankers (Sirococcus conigenum), snow blights (Herpotrichia juniperi and Phacidium infestans) and needle casts (Lophodermium seditiosum and Meria laricis). Also grey mould (Botrytis cinerea) and birch rust (Melampsoridium betulinum) are among the diseases to be controlled with fungicides. During last years Scleroderris canker has been a problem on Norway spruce, which has been since 2000 the most common species produced in Finnish nurseries. Root die-back (uninucleate Rhizoctonia sp.) on container-grown spruce and pine was a problem in the 1990s. Today the disease has become less common in modern nurseries due to improvements in hygiene and cultivation practice. Since 1991 stem lesions and top dying caused by Phytophthora cactorum has been a problem on birch. The ongoing climate change has already had effect on rusts and powdery mildews as well as other fungi infecting leaves. All diseases, which gain high precipitation and warm and long autumns. For same reasons winter stored seedlings need sprayings against grey mold. Fungal infections are also possible during short-day (SD) treatment, that is necessary for summer and autumn plantings and a beneficial step prior freezing temperatures outside or in freezer storage. Growers are encouraged to use cultural and integrated pest management techniques such as better nursery hygiene, including removing plant debris in nursery growing areas and hot water washing of containers plus removal of diseased, spore-producing seedlings and trees around the nursery.