Ground Cover Management Research Articles

Prey, management and landscape requirements of an endangered population of the Woodlark Lullula arborea in Southwest Germany

Vineyards can be valuable habitats for biodiversity conservation. For example, in Rhineland-Palatinate (Germany) over a third of the state’s critically endangered Woodlark (Lullula arborea) population breeds in vineyards along the western margin of the Upper Rhine Valley. We here aim to elucidate how local ground cover management, food availability and the proximity to settlements affect territory selection by this bird species in the region. As climate, site conditions and management differ greatly from more continental or Mediterranean wine-growing areas, conditions for Woodlark conservation may differ as well.We compared 26 Woodlark territories in vineyards with 26 nearby reference areas from which Woodlarks were absent. We recorded vineyard ground cover in the inter-rows (% cover) as well as vegetation height and composition (forbs vs. grasses). Arthropods were sampled using pitfall traps, since they are the main food resource of Woodlarks during the breeding season. In addition, the distance to built-up areas was measured. The vegetation in Woodlark territories was shorter (mean 14.2 vs. 19.6 cm) and more dominated by forbs (39% vs. 27% cover) than in absence areas. The vegetation cover in the inter-rows had no effect on Woodlark territory presence or absence. Woodlarks also favoured areas with a higher abundance of arthropods (mean abundance 69.1 vs. 57.5) and a greater distance to built-up areas (mean distance 554 vs. 373 m). We conclude that to promote the Woodlark in wine-growing areas, short, forb-rich swards should be created, facilitating arthropod detectability. This is likely to require low levels of nitrogen fertilization since fertilizers favour tall-growing grasses that outcompete forbs. Pesticide applications should be kept at a minimum to enhance arthropods as the main food source for Woodlarks and their chicks. In addition, the expansion of settlements into breeding areas of Woodlarks should be avoided.

Effect of the ground cover management on Cacopsylla bidens (Šulc, 1907) populations in pear orchards

Effect of the ground cover management on <i>Cacopsylla bidens</i> (Šulc, 1907) populations in pear orchards

Effects of ground cover management on improving water and soil conservation in tree crop systems: A meta-analysis

Tree crops are mainly planted on sloped farmland, which can lead to soil erosion caused by runoff. As an important tree crop management strategy, ground cover management has been effective in controlling runoff generation and soil loss. However, a global overview is needed to comprehensively quantify the effectiveness of ground cover on water and soil conservation. This study aims to conduct a worldwide meta-analysis of 85 peer-reviewed publications from Web of Science and China National Knowledge Infrastructure (CNKI) databases, to quantify the effectiveness of ground cover in reducing runoff, soil and nutrient losses. Overall, ground cover management significantly reduced runoff, soil loss, and nitrogen and phosphorus losses in runoff by 48.5%, 70.5%, and 53.4% and 56.9%, respectively. The magnitude of the effect of ground cover management mostly depended on ground cover types, land slope and climatic conditions. Cover cropping showed more efficiency in reducing runoff, soil and nutrient losses than mulch management. Legume cover crops were less effective than non-legumes, which was mainly attributed to the greater vegetation coverage of the perennial non-legume grasses than the annual legumes. Ground cover showed the most capacity to conserve water and soil at slopes between 10 and 15°, with the tendency to lose effectiveness when field slopes were greater than 15°. When pooling data according to different climatic conditions, the reduction of runoff, soil and nutrient losses were highest when mean annual precipitation and temperature were above 800 mm and 20 °C, respectively. This study can serve as a scientific basis for policy makers and tree crop managers in controlling soil erosion and land degradation based on ground cover type, physical topography and the climate where the agroecosystem is located.

Soil organic carbon and nitrogen pools are increased by mixed grass and legume cover crops in vineyard agroecosystems: Detecting short-term management effects using infrared spectroscopy

The incorporation of cover crops in orchards and vineyards can increase soil organic carbon (OC) and improve nitrogen (N) availability. This study compared how three herbaceous under-vine cover crop assemblages affected OC and N pools in four edaphically distinct vineyard agroecosystems. Using physical fractionation and soil spectral analysis we: 1) compared effects of grass and legume mono- and poly-cultures on total, coarse (≥50 µm) and fine (<50 µm) pools of OC and total N (TN), as well as extractable N (ExN), and 2) assessed predictions of OC and TN pools by infrared spectroscopy (IRS) and partial least squares regression analyses (PLSR). Compared with the control treatment, total, coarse and fine fraction OC were greater in the presence of grasses and legumes; ExN was increased 38% by legumes, and 78% in legume-grass mixture. With initial calibration, we used one soil spectral analysis to successfully derive models predicting contents of OC in the whole soil, and the allocation of OC to coarse and fine fractions. In addition to demonstrating the efficacy of incorporating grass and legume cover crops into vineyard cropping systems to improve OC and the storage and availability of N across diverse soil types, this study confirms the ability of IRS/PLSR to predict changes in OC concentrations related to differential ground cover management. IRS/PLSR is an important and practical approach for the rapid quantification of short-term management impacts on SOM pools, contributing significantly towards improved understanding of soil C and N dynamics in vineyard agroecosystems.

Different Ground Vegetation Cover Management Systems to Manage Cynodon dactylon in an Irrigated Vineyard

Ground cover management in vineyards in Spain is focused on minimizing soil erosion and compaction. Such practices have influenced the weed community structure in the inter-rows, contributing to the spread of the high noxious weed Cynodon dactylon (L.) Pers. This fact highlights the need for further investigation of the interaction between ground cover practices and weed control techniques. In this study, the effect of four different ground cover managements (M) in the inter-rows on C. dactylon population dynamics (changes in coverage and frequency) was assessed over three seasons (2015–2017): (M1) a no-till spontaneous vegetation ground cover managed by shredding; (M2) a no-till spontaneous vegetation ground cover managed by shredding plus herbicide application, (M3) tilled soil and spontaneous vegetation growing; and (M4) tilled soil and a barley cover crop seeded (Hordeum vulgare L.). Cynodon dactylon and the other weeds responded differently to the various weed control methods. After three seasons, the barley cover crop was the most efficient management system to control C. dactylon and other weeds. Final soil cover in barley cover crop and tilled soil with spontaneous vegetation were 0.5% and 1.1%, respectively, compared to 3.7% and 7.7% obtained by spontaneous vegetation shredded with and without herbicide application, respectively. In addition, total weed frequency varied from 9.7% for barley cover crop to 45.8% for spontaneous vegetation only shredded. Weed community composition changed due to the pressure exerted by each management and the adaptive strategy of the different species. This study highlights the importance of knowledge of how vegetation management influences weed flora to improve the sustainability of wine grape production systems.

Impact of vineyard ground cover management on the occurrence and activity of entomopathogenic nematodes and associated soil organisms

Viticulture is a valuable sector worldwide with an extraordinary socio-economic impact in Spain. Numerous pests and diseases threaten vineyards, and their management primarily relies on the use of conventional agrochemicals. The current paradigm of sustainability pursues the implementation of ecologically sound strategies in vineyard ecosystems. The use of cover crops is arising as an alternative with numerous benefits, including favoring above-belowground biodiversity and the presence of beneficial soil organisms such as the entomopathogenic nematodes (EPNs). We hypothesized that the use of specific cover crops in vineyards might enhance the natural occurrence and activity of EPNs by modulating the assemblage with associated organisms. We performed the experiments in an ongoing experimental vineyard (Vitis vinifera var Tempranillo, clon RJ-26, rootstock ‘110-Richter’) located in Logroño (Spain), drove with different soil management systems (three replicates each): conventional tillage practice and the cover crops (i) seeded with Bromus catharticus (Poaceae), (ii) flower-driven, and (iii) spontaneous. We took four soil composite samples per plot (n = 48 per sampling time) late spring and early autumn in two consecutive years (2017 and 2018). By using species-specific primers/probes qPCR sets, we screened for the presence and abundance of eight EPNs species and 12 related soil organisms: six nematophagous fungi, four free-living nematodes, and two ectoparasitic bacteria. Additionally, we assessed the EPN activity by the traditional insect-bait method. Overall, we recorded higher EPN numbers or activity rates on cover crops than on bare soils. However, some of the results were divergent among no-till treatments. We observed not only higher EPN abundance and activity on spontaneous covers but lower numbers of antagonistic organisms, particularly endoparasitic nematophagous fungi. Thus, according to our results, the use of spontaneous covers could be the most promising strategy to support the conservation biological control service provided by the naturally occurring EPN species in vineyards, plus with a low cost for the sector.

Long-term response of groundcover components to organic and conventional weed control in shaded and open-sun coffee in Nicaragua

The weed-free period is employed to evaluate the effectiveness of practices to reduce crop loss to weeds. To orient sustainable cropping system approaches in perennial crops such as coffee which are often grown with trees, orchard floor or groundcover management has been proposed to address not only crop loss, but also soil protection, plant nutrition, habitat for beneficial organisms and labor and input costs. The results of a long-term experiment in Masatepe, Nicaragua, comparing two intensities of organic and conventional coffee management under four combinations of deciduous and evergreen trees either leguminous (Inga laurina and Samanea saman) and non-leguminous (Simarouba glauca and Tabebuia rosea) and full sun concluded that with selective weed management under trees, soil is protected with both low-growing, shallow-rooted cover vegetation and tree leaf litter without yield loss, while also reducing herbicide and labor use. Over 11 years, treatments with trees compared to full sun coffee showed near absence of bare soil (P < .001) and increasing presence of leaf litter (P < .001) and cover vegetation (P < .001), especially in the first 8 years. Selective control, either herbicide or manual, resulted in minimal bare soil, a declining area covered by weeds and increased area, from 40 to 70%, under cover vegetation. Selective control with herbicides had less weedy vegetation than manual selective control. Trees compared to full sun showed increased accumulation of whole leaf and fractionated leaf layers measured in the dry season with treatments including Inga laurina greater than other tree treatments. Labor and herbicide costs declined with increasing time under trees (P < .001), while selective control reduced herbicide use with higher labor costs. A regression of groundcover components on coffee berry yields explained less than 10% of variability. Two research priorities are identified to increase the contribution of groundcover components to sustainable coffee systems – 1) cover vegetation species and management in water conservation and use and 2) the role of tree species and their litter on water, soil biology dynamics and O horizon formation.

Weed species, not mulching, affect web‐building spiders and their prey in organic fruit orchards in South Africa

AbstractWeed infestation affects economically relevant orchard properties, including tree performance, yield, and fruit quality negatively, and weeds are therefore often controlled by herbicide application in conventional farming. The addition of organic mulch below tree canopies has been proposed as an alternative reliable practice to suppress weeds and preserve soil moisture in organic farming. Mulching, however, may also affect arthropod pest and natural enemy populations, which highlights the need for simultaneously assessing weed, natural enemy, and animal pest communities in mulch experiments. This study addresses the limited knowledge about nonchemical ground cover management strategies for the control of plant and animal pests in orchards as a major constraint for organic growers. Here, we hypothesize that decisions about ground cover management practices in organic temperate fruit orchards affect the composition of web‐building spider communities and their functional role as natural enemies of pest arthropods through effects on weed and insect pest communities. We studied weed, prey, and spider communities, as well as spider diet composition, in four temperate fruit types (apricot, peach, plum, and quince) on a single farm in the Western Cape, South Africa. We established experimental plots with and without addition of dead organic mulch under fruit tree canopies. Addition of organic mulch did not significantly affect weed cover under trees or the taxonomic composition of weed or spider communities over the eight‐month study period. However, independent of mulching, the taxonomic composition of weed communities was significantly related to the composition of potential prey and spider communities. These relationships indirectly affected the prey composition of web‐building spiders. These results suggest that the identity of weed species in the study orchards had a pronounced effect on the diet composition and functional role of web‐building spiders. Future research should focus on the value of individual plant species for the promotion of pest control services provided by spiders across larger spatial scales and with higher levels of replication to allow for wider generalizations. The expected results would not only be relevant for weed control but could also be considered during the development of future flower strips in orchards.

Effects of Ground Cover Management on Insect Predators and Pests in a Mediterranean Vineyard.

Conservative techniques, such as ground cover management, could help promote viticulture sustainability, which is a goal of conservation biological control, by providing shelter and food sources for predatory insects. A field experiment was conducted in a Mediterranean vineyard to evaluate ground cover management impacts on predatory insect and potential grapevine pest abundance and diversity, both on the ground and in the grapevine canopy. Three different ground cover management techniques (tillage, spontaneous cover and flower-driven cover) were tested for two years (2016 and 2017). Overall, the ground cover management significantly affected the abundance of important epigeal predators, of which carabids, forficulids and staphylinids were the most captured. The carabid abundances under both the cover crop treatments were found to be approximately three times higher compared with that under the tillage treatment. In contrast, the canopy insect abundance in the vineyard was similar among the treatments for both the predators and the potential grapevine pest species. These results indicate that cover crop vegetation can be used in vineyards to enhance predatory insect abundance and may improve agroecosystem resilience.

Effects of Ground Cover Management on Biotic Communities, Ecosystem Services and Disservices in Organic Deciduous Fruit Orchards in South Africa

Organic orchards may have higher biodiversity and levels of ecosystem services compared to conventionally managed orchards. However, it is not well understood how management decisions within organic orchards alter biotic communities and ecosystem service levels. The simultaneous provision of individual ecosystem services and mitigation of disservices is crucial for organic growers who cannot replace natural regulatory processes by artificial inputs. This study addresses one of the major constraints for organic fruit production in South Africa, namely the availability of strategies for pest control and nutrient management in soils. A field experiment was established to study the impact of a treatment with dead organic mulch compared to controls on the composition of biotic communities, the simultaneous provision of ecosystem services, and the mitigation of disservices in organic pome fruit orchards in the Western Cape Province. Mulching did not significantly reduce weed cover or alter the taxonomic composition of weed communities, but affected soil organisms. Mulched subplots had significantly higher densities of Collembola and phytophagous nematodes and lower microbial activity and woodlice numbers. Independent of mulch treatment, both orchard type (conventional: apricot & organic: apricot, peach, plum and quince) and weed cover had pronounced effects on the composition of biotic communities and associated ecosystem service and disservice potentials. The community composition of plants, microbes and web-building spiders differed significantly between organically and conventionally managed plots. The composition of communities and levels of ecosystem service and disservice potentials also differed significantly between organic orchards of different fruit type. The two potential pest groups (phytophagous nematodes and arthropods) were most abundant in peach subplots with high weed cover and tree age and least abundant in conventionally managed apricot plots. These results emphasize the crucial importance to consider weed-microbe-animal interactions when developing management practices in organic orchards. Management decisions in organic orchards hold the potential to affect biotic communities to the benefit of pest control and soil nutrient services, but can also result in unexpected detrimental effects on ecosystem services.

Role of groundcover management in controlling soil erosion under extreme rainfall in citrus orchards of southern China

Extreme rainfall is becoming more frequent and intense due to climate change and increasing human activity. Changes in rainfall will increase the risks and uncertainty of water erosion from orchards. Groundcover management is an important factor affecting hydrological and erosive processes of orchards. However, the roles of different groundcover managements for controlling soil water erosion caused by extreme rainfall are not fully understood. In this study, four groundcover managements (i.e., control bare land, orchard with no cover, orchard with grass cover and orchard with cover crops) were used to analyze runoff and erosion characteristics related to extreme and ordinary rainfalls in the red soil region of China. Based on the rainfall-runoff data measured on runoff plots, 356 natural rainfall events from 2001 to 2012 were analyzed, and rainfall depths and maximum 30-min rainfall intensities were used to select extreme rainfall events, according to the criteria of the World Meteorological Organization for extreme rainfall. There were 25 extreme rainfall events with a probability of 7.0% during the study period. Extreme rainfall events played the destructive role in inducing soil loss. The average extreme runoff coefficient and soil loss amount were 2.8 and 11.1 times higher than the values from ordinary rainfall, respectively. The contribution of extreme rainfall to sediment yield was 44.2%, which far higher than those to runoff generation (15.8%). Moreover, the runoff coefficients and erosion amounts varied greatly among the different groundcover managements under extreme rainfall, and were ranked in the following order: control bare land > orchard with no cover > orchard with cover crops > orchard with grass cover. However, the highest percentage of soil loss amount caused by extreme rainfalls were 59.0% in orchard with cover crops, and the lowest in orchard with grass cover (26.0%). Therefore, extreme rainfall should cause more attention in improving the groundcover management strategy for orchard soil erosion control, and groundcover like grass cover was extremely needed even after interplanting crops for the serious soil loss.

Diverging Effects of Landscape Factors and Inter-Row Management on the Abundance of Beneficial and Herbivorous Arthropods in Andalusian Vineyards (Spain).

Land use at landscape and field scales can increase the diversity and abundance of natural enemies for pest control. In this study, we investigated interactions between landscape elements (semi-natural vegetation, olive orchards, vineyards, other agricultural areas) and inter-row management (vegetation cover vs. bare soil) in relation to arthropod populations in Andalusian vineyards. Arthropods were collected from grapevine foliage in 15 vineyards using suction sampling. Landscape structure was analyzed within a 750 m radius surrounding the studied vineyards. Arthropods were categorized into functional groups (predators, parasitoids, herbivores), and their responses to the most influencing factors were analyzed by likelihood methods and model selection. Of the total of 650 arthropods collected, 48% were predators, 33% herbivores and 19% parasitoids. Numbers of predatory aeolothrips, parasitoids and herbivorous cicadas in the study vineyards decreased with an increased proportion of vineyards in the surroundings. Spider populations in vineyards increased with increasing proportions of other agricultural fields (non-flowering crops) in the surroundings. Semi-natural elements and olive orchards had no influence on the abundance of collected arthropods. We observed synergistic effects between landscape elements and inter-row management. The total numbers of arthropods, herbivores and parasitoids in vineyards benefitted from inter-row vegetation, while spiders benefitted from bare soil. Our findings underline the importance of both surrounding landscape elements and vineyard ground cover management to promote beneficial arthropods for potential natural pest control.

Challenges and ways forward in pesticide emission and toxicity characterization modeling for tropical conditions

PurposeIn tropical cropping systems, pesticides are extensively used to fight pests and ensure high crop yields. However, pesticide use also leads to environmental and health impacts. While pesticide emissions and impacts are influenced by farm management practices and environmental conditions, available Life Cycle Inventory (LCI) emission models and Life Cycle Impact Assessment (LCIA) toxicity characterization models are generally designed based on temperate conditions. There is, hence, a need for adapting LCI and LCIA models for evaluating pesticides under tropical conditions. To address this need, we aim to identify the characteristics that determine pesticide emissions and related impacts under tropical conditions, and to assess to what extent LCI and LCIA models need to be adapted to better account for these conditions.MethodsWe investigated the state-of-knowledge with respect to characteristics that drive pesticide emission patterns, environmental fate, human and ecological exposures, and toxicological effects under tropical conditions. We then discuss the applicability of existing LCI and LCIA models to tropical regions as input for deriving specific recommendations for future modeling refinements.Results and discussionOur results indicate that many pesticide-related environmental processes, such as degradation and volatilization, show higher kinetic rates under tropical conditions mainly due to higher temperatures, sunlight radiation, and microbial activity. Heavy and frequent rainfalls enhance leaching and runoff. Specific soil characteristics (e.g., low pH), crops, and cropping systems (e.g., mulching) are important drivers of distinct pesticide emission patterns under tropical conditions. Adapting LCI models to tropical conditions implies incorporating specific features of tropical cropping systems (e.g., intercropping, ground cover management), specific drift curves for tropical pesticide application techniques, and better addressing leaching processes. The validity domain of the discussed LCI and LCIA models could be systematically extended to tropical regions by considering tropical soil types, climate conditions, and crops, and adding active substances applied specifically under tropical conditions, including the consideration of late applications of pesticides before harvest and their effect on crop residues and subsequent human intake.ConclusionsCurrent LCI and LCIA models are not fully suitable for evaluating pesticide emissions and impacts for crops cultivated in tropical regions. Models should be adapted and parameterized to better account for various characteristics influencing emission and impact patterns under tropical conditions using best available data and knowledge. Further research is urgently required to improve our knowledge and data with respect to understanding and evaluating pesticide emission and impact processes under tropical conditions.

Ground cover management in a Mediterranean vineyard: Impact on insect abundance and diversity

Sustainable agriculture requires the support of new tools for successful and low-impact management of pests and diseases at global and local scales. The implementation of cover crops is considered a promising alternative ecological structure for sustainable agriculture, because they provide refuge to natural enemies of pests. Specifically, we hypothesised that implementing cover crop vegetation in a vineyard can enhance populations of natural enemies as a measure to support conservation biological control. We analysed insect abundance and diversity on Vitis vinifera var. Tempranillo (clon RJ-26, rootstock “110-Richter”) in a Mediterranean vineyard located in La Rioja, Spain from spring to autumn 2016–2017. Two types of sampling systems (pitfall traps and vacuum sampling) were used in each of the three evaluated ground cover management approaches (n = 3): (i) tillage, (ii) spontaneous cover, and (iii) flower-driven cover. A total of 58 families that belonged to four functional subgroups of insects (predators, parasitoids, phytophagous insects, and pollinators) were found. Overall, differences among the three treatments were only detected for total abundance of insects collected in the ground traps, and the “spontaneous cover” treatment showed significantly higher predator richness and abundance. However, the higher Shannon–Wiener value was recorded for “flower-driven cover” at both the ground and canopy levels. In addition, the abundance of predators, parasitoids and phytophagous insects in the ground traps for both cover crop treatments was more than two times higher than that observed in “tillage” treatment. Several predator taxa, such as ants, ground beetles, earwigs, and vespoid wasps had significantly higher representation under spontaneous cover treatment. Moreover, for parasitoids, the “flower-driven cover” treatment revealed higher Hill numbers values (0D, 1D, and 2D) at the canopy level, although no significant differences were observed. These results indicate that vegetation cover could be used to promote beneficial entomofauna in vineyards and thus be an effective conservation biological control tool.

Influence of Groundcover Vegetation, Soil Physicochemical Properties, and Irrigation Practices on Soil Fungi in Semi-arid Vineyards

Although plants are known to have a strong influence on soil biota, the effect of groundcover vegetation in perennial cropping systems on soil fungi has been little explored. We surveyed extensively managed vineyards to determine how plant community functional characteristics, soil factors, and irrigation management related to the abundance of two guilds of soil fungi that may play a role in plant-soil feedback (entomopathogenic fungi represented by Beauveria bassiana, and the pathogenic species complex, Ilyonectria spp.). We found that plant community characteristics were related to fungal abundance for both fungi assayed. Beauveria bassiana increased with native species, annual plants, and legumes consistently across sampling periods. Ilyonectria spp. increased with the abundance of forbs and exotic species, though only the relationship with forbs was consistent across sampling periods. Both fungal guilds increased with increasing soil organic matter. The use of dual or sprinkler irrigation systems also increased Beauveria bassiana and Ilyonectria spp. in vineyard soils. Overall, groundcover vegetation played a significant role in driving abundance of these important groups of soil fungi. Groundcover management may therefore be a viable tool to manipulate soil fungi with the potential for improving ecosystem services such as conservation biological control of soil dwelling insect pests and deterring pathogens in perennial cropping systems.

Ground cover management with mixtures of flowering plants to enhance insect pollinators and natural enemies of pests in olive groves

The potential of ground cover management with mixtures of selected plants to provide habitats for pollinating insects and natural enemies of pests in an olive grove in southern Greece, was studied over a period of 3 years (2011–2013). The management consisted of the establishment of 3 m2 patches of sown plant species or spontaneous natural vegetation between trees along tree lines. The sown plant species in the mixtures were Sinapis alba L. (Brassicaceae), Glebionis segetum (L.) Fourr. and Glebionis coronaria (L.) Cass. ex Spach (Asteraceae), Vicia sativa L. and Pisum sativum L. (Fabaceae), Borago officinalis L. (Boraginaceae), Coriandrum sativum L. and Pimpinella anisum L. (Apiaceae). Sowing was performed in autumn or spring and the peak flowering period occurred at the end of March to end of April, and at the end of May to end of June, respectively. Visual estimation of flower cover, counts of pollinator landings on flowers and presence of beneficial arthropods (suction sampling) were performed in three 7–10 day intervals during peak flowering, for each experimental year. Overall, patches with sown plant mixtures attracted higher numbers of pollinating Hymenoptera compared to native vegetation, especially mining bees and honey bees (Apis mellifera) as well as megachilids and bumble bees (Bombus spp.). Sinapis alba, present in both sown and native vegetation patches, attracted mainly mining bees and honey bees. The flowering mixture with C. sativum and B. officinalis was more attractive to honey bees than the one with G. coronaria as main flowering species but they were both equally attractive to mining bees, although the species composition may well have been different. Hymenopterous parasitoids, primarily Braconidae and Chalcidoidea, were sampled from the patches and the olive fruit fly parasitoid Opius concolor (Hymenoptera: Braconidae) was recorded on olive trees adjacent to the flowering patches. Large numbers of predators, namely Orius sp. (Hemiptera: Miridae) and lacewings (Neuroptera: Chrysopidae), were recorded in the patches, principally in those with the mixture containing mostly S. alba. Our results suggest that ground cover in patches with suitable flowering species could be part of a sustainable olive crop management system, providing food and refuge for pollinating insects and beneficial arthropods.

Long-term cover cropping seasonally affects soil microbial carbon metabolism in an apple orchard

ABSTRACT Groundcover management can significantly affect soil microbial metabolic activities, especially carbon metabolism, in apple orchards. However, there have been few studies on the effects of groundcover on the seasonality of soil microbial carbon metabolism. We, therefore, studied soil microbial carbon metabolism in an apple orchard on China’s Loess Plateau under four single species cover crops (the grass Dactylis glomerata L., and the legumes Trifolium repens, Coronilla varia L., Lotus corniculatus L.) during spring, summer and fall. Cover cropping significantly, but differentially, promoted soil microbial carbon metabolism in spring and fall. However, cover cropping leads to a significant reduction of soil moisture in spring and summer due to the competition of soil moisture between the cover crops and apple trees, which probably lead to the changes in types of carbon substances metabolizing by soil microbes in summer. Besides, cover crop significantly enhanced soil organic carbon contents between three seasons while clean cultivation had slight, non-significant effects. The promotion of soil microbial metabolic activities was probably an important mechanism for the carbon accumulation, and we postulate that leguminous cover plants may have significantly different effects, mediated through their root exudates, from grasses on soil carbon contents.

Challenges – the impact of climate change on the nutritional management of Hungarian orchards

The agricultural sector is increasingly exposed to both environmental and economic risks due to the phenomena of climate change and climate variability. Fruit growth and productivity are adversely affected by nature’s wrath in the form of various abiotic stress factors. Climate change and extreme climatic events are predicted to increase in intensity, frequency, and geographic extent as a consequence of global climate change. It is no doubt that frequency of unexpected climatic events and their growing rate result in an increasing amount of problems for fruit growers globally. Today, climate change impacts are the most serious problems for Hungarian fruit growers as well. It can be stated that the nutrient demand of fruit trees can be supplied only under even worse conditions.&#x0D; Therefore, it is so important to know and apply adaptation and mitigation strategies in horticulture to improve fruit quality and yield. In the last ten years, at the Faculty of Agricultural and Food Sciences and Environmental Management at University of Debrecen expanded studies have been made to prove the importance of groundcover management in horticultural applications. In this mini review paper, is presented, how the university's researches contributed to the expansion of knowledge of preservation of soil moisture and what advice we can provide for fruit growers to face the challenges of climate change.

Mealybug preference among clover cultivars: testing potential groundcover plants to dissociate mealybugs from grapevines

The choice of groundcover plants used under grapevines may reduce the quantity of mealybugs found on grapevines in New Zealand vineyards. Preferences of Pseudococcus calceolariae and P. longispinus mealybugs on five clover cultivars were tested under ‘no-choice’ and ‘choice’ conditions. Two plants of each cultivar: ‘Karridale’(KS) (Trifolium subterraneum, L.), ‘Tripoli’ (TW), ‘Nomad’ (N) (T. repens), ‘Crimson cv’ (C) (T. incarnatum) and ‘Strawberry cv’ (S) (T. fragiferum) grown in pots, were arranged in randomised designs for the no-choice and choice tests and inoculated with newly emerged mealybugs. In the no-choice test, significantly more mealybugs (either species) were observed on KS and C than on TW, N, or S plants after 21 days. In the choice test, significantly more P. calceolariae were observed on KS than on TW, N, or S, while mealybug numbers on C were intermediate. Numbers of P. longispinus were significantly higher on KS and C than on TW, N or S. Mealybugs demonstrated preferences for KS and C over TW, N or S. These findings could aid development of recommendations for groundcover management in vineyards.

Soil microbial community changes associated with ground cover management in cultivation of Ducasse banana (Musa sp. ABB, Pisang Awak subgroup) and suppression of Fusarium oxysporum

The pathogen Fusarium oxysporum formae specialis cubense (FOC) has caused devastating economic losses in banana production systems. An improved understanding of how agronomic practices can affect the soil microbiome and related agro-ecosystem services, such as disease suppression, may assist in reducing impacts of FOC. This is the first study to investigate whether suppression of FOC, due to use of ground cover management in cultivation of Ducasse banana, is associated with changes in the soil microbiome. A field experiment was undertaken at a site where commercial production of Ducasse bananas had ceased due to Fusarium wilt (indicating high soil inoculum levels). Suppression of Fusarium wilt tended to increase with time in Ducasse bananas cultivated with ground covers compared to bare soil (the vegetated and bare treatments respectively). Terminal restriction fragment length polymorphism (TRFLP) and amplicon sequencing were used to profile microbial communities in bulk soils during the course of the field experiment. TRFLP analysis identified statistically significant changes in the structure of soil microbial communities over time in the vegetated treatment and identified potential bio-markers related to disease suppression. Fungal amplicon sequencing confirmed the findings of TRFLP, and demonstrated reduced dominance of FO in the vegetated treatment was associated with disease suppression. Limitations of using the ITS region for FO/FOC analysis were also determined. The results of this study provide an improved understanding of the mechanisms involved in suppression of FOC by use of ground covers in cultivation of Ducasse bananas, which may be useful for other agricultural production systems.