Effectiveness of biological protection of cabbage against pests in the conditions of the Primorsky Territory

The results of the use of entomophages and biological products to regulate the number of cabbage pests (cabbage moth Mamestra brassicae L., cabbage butterfly Pieris brassicae L., turnip butterfly Pieris rapae L., diamondback moth Plutella xylostella L.) are presented. The study was carried out in the Primorsky Territory in 2018-2020. The efficiency of Trichogramma ussuricum Sorokina applications was assessed on cabbage varieties. The effectiveness of the entomophage against the cabbage moth varied from 33.3 to 66.6%, against the turnip butterfly - from 32.6 to 70.2%. In field experiments the effectiveness of biological products Fitoverm EC (0.09 l/ha), Akarin EC (1.6 l/ha), Proclaim WG (0.3 kg/ha), Bitoxibacillin (10 l/ha), Bitoxibacillin P (2 kg/ha), Lepidocid SC (2 l/ha), Lepidocid P (2 kg/ha) against diamondback moth are studied. Cabbage plants were sprayed with the preparations once. Pest counts were carried out before treatment and after treatment on the 5th, 10th and 15th day in accordance with the approved methods. Bioinsecticide Proclaim showed a high efficiency of 93.0-100% on the 5-10th day. The effectiveness of preparations based on aversectin C and avertin N was 65.0-88.6%. Using the biological product Bitoxibacillin and Lepidocid a decrease the number of diamondback moth relative to the control by 61.2-97.5 и 65.0-78.0% was registered.

Using flower strips to promote green lacewings to control cabbage insect pests

Habitat management improves biological control by increasing the abundance and fitness of natural enemies through the provision of floral resources along field edges or between crops. Among the natural enemies reliant on flower resources, green lacewings often stand out due to their abundance, predation capacity and polyphagy. We evaluated the impact of tailored flower strips on the enhancement of natural enemies, especially green lacewings, in three organic cabbage (Brassica oleracea) farms in Southern Sweden. Insects were sampled from the flower strips, and cabbage pests and predators were visually recorded in the crop. In a laboratory assay, the pollen feeding preferences of Chrysoperla carnea (Stephens, 1836) were evaluated in a dual-choice test. The pollen consumed by the Chrysopidae was extracted from laboratory and field specimens, then quantified and identified. Flower strips were found to attract predators and parasitoids, whose abundance increased as flowers bloomed. Cabbage plants next to the flower strips showed lower pest infestation as compared to cabbage plant control, although no significant differences were observed in the number of predators. Chrysopidae used flower strips as feeding, reproduction and shelter sites and mainly consumed pollen from Phacelia tanacetifolia Benth. Under laboratory conditions, C. carnea showed a preference for P. tanacetifolia and Coriandrum sativum L. pollen over Borago officinalis L. and Fagopyrum esculentum Moench. We show that tailored flower strips could be an efficient tool for enhancing beneficial arthropods and should be considered in integrated pest management for cabbage crops.

Evaluation of a first-event sampling model for monitoring cabbage pests

First-event sampling models for monitoring diamondback moth Plutella xylostella (Lepidoptera: Plutellidae) and small white butterfly, Pieris rapae (Pieridae) are used in integrated production systems of cabbage. Decision-making accuracy and reduced labour needs of those models were unknown compared to fixed-sample monitoring. This we addressed through computer simulations of the currently most used first-event sampling plan for cabbage in DPR Korea. Indeed, this sampling plan in five subplots of a cabbage field at a sampling limit of a maximum 10 plants each, appeared less labour intense than many fixed-sample monitoring plans. However, only a medium accuracy of infestation estimates and correct decision-making for or against pest control was achieved, particularly at high pest densities. If accepting such medium accuracy, the current sampling plan could be reduced from five to three subplots at a sampling limit of 10 plants each, or to a maximum of five assessed plants per each of five subplots, this is, without further loosing accuracy whilst saving labour. Such sampling requires little investment in time and might be therefore applied and validated across more cabbage productions systems of East Asia. Ultimately, first-event sampling, as other sampling plans will remain a compromise between accuracy and practicability.

Bio-efficacy of entomopathogenic nematodes, Steinernema feltiae and Heterorhabditis bacteriophora against the Cabbage butterfly Pieris brassicae (L.), under laboratory conditions

BACKGROUND: Keeping in view the serious health and environmental apprehensions associated with the use of pesticides, entomopathogenic nematodes have the potential to supersede larvicidal activity for the management of various insect pests. RESULT: The lab experiments were conducted to test the pathogenicity of two EPNs species S. feltiaeand H. bacteriophora at different (IJs/cm2) concentrations against cabbage pests. Based on the pathogenicity of strains, only two isolates effectively show larvicidal activity. The native isolate was obtained from soil samples, collected from Rajgarh, Hamachi Pradesh, India. Petri dish bioassay use nematodes S. feltiae HR1 and H. bacteriophora HR2 species dose (0, 10, 20, 40, 80, 160/ IJs/cm2). The highest (%) 2nd instar larval mortality was recorded in treatments with H. bacteriophora and S. feltiae @ 160 /IJs/cm-2 were (72.08, 67.42 percent). And 4th instar larval mortality was recorded in treatment with H. bacteriophora, and S. feltiae @ 160 /IJs/cm-2 were (85.38,69.50 percent). The next best treatments in order of their efficacy’s pupae mortality were H. bacteriophora and S. feltiae @ 160 /IJs/cm-2 (74.12, percent) both are seam result, H. bacteriophora and S. feltiae @ 80 /IJs/cm-2 (62.12, 58.58 percent). Larvicidal activity after 48- and 72-hours exposure, the S. feltiae and H. bacteriophora (1.0, 1.30, 1.60, 1.90, 2.20 /IJs/cm2) showed potent larvicidal activity with LC50, LC75 and LC90 of all instars and pupae show high mortality. The strain inhibits the larval and pupal development 48 to 72 hr exposer time with LC50 range from 11.30 to 39.94, LC75 18.15 to 73.54, LC90 61.80 to 99.21.CONCLUSION: These studies demonstrate the challenge for cabbage butterfly P. brassicae. The local indigenous strains of EPNs (S. feltiae HR1, H. bacteriophora HR2) as a good biocontrol agent against, cruciferous vegetables crop pest P. brassicae.

Cabbage Production in West Africa and IPM with a Focus on Plant-Based Extracts and a Complementary Worldwide Vision

In urban and peri-urban areas in West Africa, the cabbage Brassica oleracea L. (Brassicaceae) is protected using repeated high doses of synthetic insecticides. After a brief description of available IPM components, this paper presents a literature review focused on the botanical extracts that have been experimented with at the laboratory or in the field in West Africa against major cabbage pests. The literature reviewed mentions 19 plant species from 12 families used for cabbage protection in the subregion. The species most used are Azadirachta indica, Capsicum frutescens, Ocimum gratissimum and Ricinus communis. An overview of the world literature showed that a total of 13 plant species belonging to 8 families used to control cabbage pests are reported from the rest of Africa, and 140 plant species belonging to 43 families from the rest of the world. The most commonly used and tested plant species against insect pests in the three geographical areas considered is A. indica.

Effet des extraits aqueux de Calotropis procera sur les principaux ravageurs du chou en culture au Sénégal

Au Sénégal, le chou est l’un des légumes les plus cultivés et consommés, de par son cycle relativement court (60-90 jours après repiquage) et sa possibilité d’être cultivé toute l’année. Cependant il est attaqué par plusieurs ravageurs tels que Plutella xylostella (L.) (Lepidoptera, Plutellidae), Hellula undalis (F.) (Lepidoptera, Pyralidae) et Spodoptera littoralis (B.) (Lepidoptera, Noctuidae). L’objectif de cette étude était de contribuer à la lutte contre ces ravageurs du chou en culture dans la zone des Niayes en utilisant les extraits aqueux à base de feuilles de Calotropis procera (Apocynaceae). L’étude a été menée sur 28 parcelles élémentaires dans la zone des Niayes (durant la période du 3 janvier au 22 mars 2019). Les formulations d’extrait de feuilles de C. procera utilisant comme solvant l’eau de robinet et l’eau de puits (ER et EP), appliquées à des temps différents le matin (ERM, EPM) et le soir (ERS, EPS) ont montré leurs efficacités sur les larves de P. xylostella et H. undalis. Par contre, les extraits ne sont pas efficaces sur S. littoralis (P-value= 0,672). En plus de leurs effets biocides, les extraits à base de feuilles de C. procera semblent accélérer la croissance des plants de chou. La nature du solvant et la période du traitement n’ont pas montré une différence significative.Mots clés : Biocide, Brassicassée, Niayes, lutte biologique English title: Aqueous extracts effect of Calotropis procera on the principal cabbage pests in culture in Senegal In Senegal, the cabbage is one of the most cultivated and consumed vegetables, from its relatively short cycle (60-90 days after road repair) and the possibility of being cultivated all the year. However it is attacked by several pests such as Plutella xylostella (L.) (Lepidoptera, Plutellidae), Hellula undalis (F.) (Lepidoptera, Pyralidae) and Spodoptera littoralis (B.) (Lepidoptera, Noctuidae). The objective of this study was to contribute on protect against cabbage pests in culture in the zone of Niayes by using the aqueous extracts containing sheets of Calotropis procera (Apocynaceae). The study was undertaken on 28 elementary pieces to in the zone of Niayes (during the period of January 3 at March 22, 2019). The formulations of extract using as solvent the water of tap and the water of well (ER and EP), applied to different times morning (ERM, EPM) and evening (ERS, EPS) showed their effectiveness on larvae of P. xylostella and H. undalis. On the other part S. littoralis was resistant to treatment (P=0,672) confirms it. In addition to their biocides effects, the extracts containing sheets of C procera seem accelerated the cabbage patches growth. The nature of solvent and the treatment period did not show a significant difference.Keywords: Biocide, Brassicasseae, Niayes, biological control

Selected Insect Pests of Economic Importance to Brassica oleracea, Their Control Strategies and the Potential Threat to Environmental Pollution in Africa

The most common destructive insect pests affecting cabbages in African smallholder farmers include Plutella xylostella, Helula undalis, Pieris brassicae, Brevycoryne brassicae, Trichoplusia ni and Myzus persicae. Those insect pests infest cabbages at different stages of growth, causing huge damage and resulting into huge yield losses. The African smallholder farmers use cultural and synthetic pesticides to control insect pests and minimize infestations. The cultural practices like crop rotation, weeding and handpicking are used to minimize the invasion of cabbage pests. However, those practices are not sufficiently enough to control cabbage insect pests although they are cheap and safe to the environment. Also, the African smallholder famers rely intensively on the application of broad-spectrum of synthetic pesticides to effectively control the cabbage pests in the field. Due to severe infestation of cabbages caused by those insects, most of African smallholder farmers decide to; first, increase the concentrations of synthetic pesticides beyond the recommended amount by manufacturers. Secondly, increase the rate of application of the synthetic pesticides throughout the growing season to effectively kill the most stubborn insect pests infesting cabbages (Brassica oleracea var. capitata). Thirdly, they mix more than two synthetic pesticides for the purpose of increasing the spectrum of killing the most stubborn insect pests in the field. All those scenarios intensify the environmental pollution especially soil and water pollution. Moreover, most of insecticides sprayed are made with broad-spectrum and are hazardous chemicals posing environmental pollution and threats to natural enemies’ ecosystems. Therefore, this paper reviews Brassica oleracea var. capitata insect pests and control measures as a potential environmental pollution threat in African smallholder farmers.

White head cabbage protection against cabbage moth in Belarus

Cabbage moth is one of the main white head cabbage pests in Belarus. The evaluation of the existing insecticides assortment has shown that their application at the initial pest number from 0.72 to 4.0 caterpillars per inspected plant has allowed reducing cabbage moth harmfulness and number by 84.0–100.0 % and increasing heads yield up to 35.5 %.