Weed Occurrence in Organic Apple Orchards by Different Cover Crops

Sowing plants that provide food resources in orchards is a potential habitat management practice for enhancing biological control. Flowering plants (providing pollen and nectar) and grasses (providing alternative prey) can benefit natural enemies in orchards; however, little is known about their relative importance. We studied the effect of management practices (flower strips, grass strips, and spontaneous grass) on arthropod predators under organic apple management regimes in apple orchards in Beijing, China. Orchards located at two different sites were assessed for 3 years (2017–2019). The cover crops had a significant impact on the abundance and diversity of arthropod predators. The grass treatment consistently supported significantly greater densities of alternative prey resources for predators, and predators were more abundant in the grass than in the other treatments. The Shannon–Wiener diversity was significantly higher for the cover crop treatment than for the control. Community structure was somewhat similar between the grass and control, but it differed between the flower treatment and grass/control. Weak evidence for an increase in mobile predators (ladybirds and lacewings) in the orchard canopy was found. Ladybirds and lacewings were more abundant in the grass treatment than in the other treatments in 2019 only, while the aphid abundance in the grass treatment was lowest. The fact that grass strips promoted higher predator abundance and stronger aphid suppression in comparison to the flower strips suggests that providing alternative prey for predators has great biocontrol service potential. The selection of cover crops and necessary management for conserving natural enemies in orchards are discussed in this paper.

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Cover crops in Victorian apple orchards: Effects on production, natural enemies and pests across a season

Crop Protection ◽

10.1016/j.cropro.2009.03.021 ◽

2009 ◽

Vol 28 (8) ◽

pp. 675-683 ◽

Cited By ~ 36

Author(s):

Nicole J. Bone ◽

Linda J. Thomson ◽

Peter M. Ridland ◽

Peter Cole ◽

Ary A. Hoffmann

Keyword(s):

Natural Enemies ◽

Cover Crops ◽

Apple Orchards

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The effect of bi-culture cover crops on soil quality, carbon sequestration, and growth characteristics in apple orchards of North Western Himalayas

Agroforestry Systems ◽

10.1007/s10457-021-00687-7 ◽

2021 ◽

Author(s):

Javaid M. Dad ◽

Suheel A. Dand ◽

Nazir A. Pala

Keyword(s):

Carbon Sequestration ◽

Soil Quality ◽

Cover Crops ◽

Growth Characteristics ◽

Western Himalayas ◽

Apple Orchards ◽

North Western

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Managing Floral Resources in Apple Orchards for Pest Control: Ideas, Experiences and Future Directions

Insects ◽

10.3390/insects10080247 ◽

2019 ◽

Vol 10 (8) ◽

pp. 247 ◽

Cited By ~ 5

Author(s):

Annette Herz ◽

Fabian Cahenzli ◽

Servane Penvern ◽

Lukas Pfiffner ◽

Marco Tasin ◽

...

Keyword(s):

Pest Control ◽

Natural Enemies ◽

Cover Crops ◽

Floral Resources ◽

Apple Orchards ◽

Functional Biodiversity ◽

Short Term ◽

Future Directions ◽

Policy Makers ◽

Mowing Regime

Functional biodiversity is of fundamental importance for pest control. Many natural enemies rely on floral resources to complete their life cycle. Farmers need to ensure the availability of suitable and sufficient floral biodiversity. This review summarizes 66 studies on the management of floral biodiversity in apple orchards, published since 1986. Approaches followed different degrees of intervention: short-term practices (mowing regime and weed maintenance, cover crops), establishment of durable ecological infrastructures (perennial flower strips, hedgerows) and re-design of the crop system (intercropping, agroforestry). Although short-term practices did not always target the nutrition of natural enemies by flowering plants, living conditions for them (alternative prey, provision of habitat) were often improved. Perennial flower strips reliably enhanced natural enemies and techniques for their introduction continuously developed. Resident natural enemies and their impact in pest control reacted positively to the introduction of a more diversified vegetation, whereas the response of very mobile organisms was often not directly linked to the measures taken. A careful selection and management of plants with particular traits exploitable by most natural enemies emerged as a key-point for success. Now the elaborated design of such measures needs to be adopted by stakeholders and policy makers to encourage farmers to implement these measures in their orchards.

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Impact of cover crop in pre-plant of apple orchards: relationship between crop health, root inhabiting fungi and rhizospheric bacteria

Canadian Journal of Plant Science ◽

10.4141/cjps-2015-013 ◽

2015 ◽

Vol 95 (5) ◽

pp. 947-958 ◽

Cited By ~ 6

Author(s):

L. M. Manici ◽

M. Kelderer ◽

F. Caputo ◽

F. Nicoletti ◽

F. De Luca Picione ◽

...

Keyword(s):

Plant Growth ◽

Cover Crops ◽

Cover Crop ◽

Apple Orchard ◽

Infection Frequency ◽

Apple Orchards ◽

Rhizospheric Bacteria ◽

Replant Disease ◽

Crop Health

Manici, L. M., Kelderer, M., Caputo, F., Nicoletti, F., De Luca Picione, F. and Topp A. R. 2015. Impact of cover crop in pre-plant of apple orchards: relationship between crop health, root inhabiting fungi and rhizospheric bacteria. Can. J. Plant Sci. 95: 947–958. Replant disease of fruit tree orchards has a multifactorial etiology, mainly due to the decline in soil biodiversity along with an increase in root rot pathogens, which can be principally countered with appropriate cropping practices. Therefore, a study on the impact of cover crops on plant health of young fruit trees in long-term orchards was performed. Bioassays were performed over two consecutive growing cycles using soil from a multigeneration apple orchard affected by replant disease. First, a cycle was performed with three cover crops (alfalfa, barley, marigold) and apple rootstock plantlets; at the end, the above-ground part of the plant was removed and root residues left in the soil. In the second cycle, an apple orchard planting was simulated upon the first experimental design. Changes of diversity and composition of root inhabiting fungi and rhizospheric bacteria were evaluated as well as apple plant growth response to the pre-plant treatments. Results suggest that one cycle with alternate plants was sufficient to induce changes at the rhizosphere level, despite soil microbial resilience caused by the same long-term soil management. Rhizospheric bacteria were generally affected by plant genotype. Findings suggest that all three different cover crops can harbor almost all fungal species that colonize apple in replanted orchards (Fusarium spp., Pythum spp., binucleate Rhizoctonia sp., Cylindrocarpon-like-fungi and a several nonpathogenic saprophytic fungi named “other”), but their infection frequency varied according to the host plant. A single pre-plant break treatment did not overall differ significantly in plant growth of subsequent apple tree; however, break with marigold, which increased abundance of nonpathogenic root inhabiting fungi more than other cover crops, gave significantly higher plant growth than obtained after barley. This study provides evidence about cover-crop potential to increase soil diversity in long-term permanent cropping systems and to manipulate root colonizing fungi involved in crop health.

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Growth and Yield Responses to Mulches and Cover Crops under Low Potassium Conditions in Drip-irrigated Apple Orchards on Coarse Soils

HortScience ◽

10.21273/hortsci.45.12.1866 ◽

2010 ◽

Vol 45 (12) ◽

pp. 1866-1871 ◽

Cited By ~ 8

Author(s):

Eugene J. Hogue ◽

John A. Cline ◽

Gerry Neilsen ◽

Denise Neilsen

Keyword(s):

Cover Crops ◽

Cover Crop ◽

Ground Cover ◽

Vegetation Management ◽

Leaf Nitrogen ◽

Growth And Yield ◽

Apple Orchards ◽

Significant Treatment ◽

K Concentration ◽

Yield Responses

Fertigated ‘Gala’ apple trees on M.9 (Malus domestica Borkh.) rootstock, planted in 1998, were grown on a coarse soil for 6 years (1998 to 2003) and exposed to eight orchard floor vegetation management treatments within the tree row. These consisted of a glyphosate control; three waste paper mulch treatments [spray-on mulch paper mulch (SM), SM incorporated with dichlobenil, SM applied over uniformly spread shredded office paper (SOP)]; and four living cover crop mulch treatments [dwarf white clover (WC), sweet clover (SC), hairy vetch (HV), and annual rye]. There were no significant treatment effects on leaf nitrogen (N) and phosphorus (P) status; however, leaf potassium (K) levels were negatively affected by the living mulch treatments in 2 of 5 years. Tree vigor was diminished by several of the orchard floor vegetation management systems in 5 of 6 years. Trees receiving an SM treatment grew more rapidly than trees receiving the ground cover treatments and trees receiving a glyphosate treatment had relatively poor but comparable growth to several of the cover crop treatments. Growth response in trees receiving SM were observed in all production years. After 6 years, cumulative yields were highest from trees receiving any of the three SM or glyphosate treatments and significantly less for any of the ground cover treatments. Weed growth within the rye cover crop was significantly reduced in comparison with the other living mulches; however, it remained sufficiently competitive to contribute to diminished overall yield and tree growth in comparison with the SM and gylphosate control treatments. Overall, response of leaf K concentration to mulch treatments was insufficient to prevent low K levels after 5 years. The addition of K through the organic mulches or recycling of K by cover crops was insufficient to avoid the development of low leaf K levels. Annual fertigation of K, in addition to N and P, appears necessary to maintain adequate vigor and yield when using mulches or cover crops in intensive, drip-irrigated apple orchards grown on coarse soils.

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Cover crops

AccessScience ◽

10.1036/1097-8542.165900 ◽

2015 ◽

Keyword(s):

Cover Crops

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New Technologies to Combat Herbicide Resistance

Outlooks on Pest Management ◽

10.1564/v30_apr_09 ◽

2020 ◽

Vol 31 (2) ◽

pp. 90-92

Author(s):

Rob Edwards

Keyword(s):

Winter Wheat ◽

Herbicide Resistance ◽

Cover Crops ◽

New Technologies ◽

Green Revolution ◽

Arable Land ◽

Limited Range ◽

Cultural Control ◽

Arable Farming ◽

The Uk

Herbicide resistance in problem weeds is now a major threat to global food production, being particularly widespread in wild grasses affecting cereal crops. In the UK, black-grass (Alopecurus myosuroides) holds the title of number one agronomic problem in winter wheat, with the loss of production associated with herbicide resistance now estimated to cost the farming sector at least £0.5 billion p.a. Black-grass presents us with many of the characteristic traits of a problem weed; being highly competitive, genetically diverse and obligately out-crossing, with a growth habit that matches winter wheat. With the UK’s limited arable crop rotations and the reliance on the repeated use of a very limited range of selective herbicides we have been continuously performing a classic Darwinian selection for resistance traits in weeds that possess great genetic diversity and plasticity in their growth habits. The result has been inevitable; the steady rise of herbicide resistance across the UK, which now affects over 2.1 million hectares of some of our best arable land. Once the resistance genie is out of the bottle, it has proven difficult to prevent its establishment and spread. With the selective herbicide option being no longer effective, the options are to revert to cultural control; changing rotations and cover crops, manual rogueing of weeds, deep ploughing and chemical mulching with total herbicides such as glyphosate. While new precision weeding technologies are being developed, their cost and scalability in arable farming remains unproven. As an agricultural scientist who has spent a working lifetime researching selective weed control, we seem to be giving up on a technology that has been a foundation stone of the green revolution. For me it begs the question, are we really unable to use modern chemical and biological technology to counter resistance? I would argue the answer to that question is most patently no; solutions are around the corner if we choose to develop them.

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