In vitro Evaluation of PHYTOSANEB-020, A Biopesticide for the Control of Mealybug (Planococcus ficus) on Rosa multiflora and Bougainvillea spectabilis in Kimwenza-Mission

This study focused on the in vitro evaluation of the effectiveness of Phytosaneb-020, a bio-pesticide on Mealybug Planococcus ficus (Signoret) which infests Rosa multiflora (Rosa polyantha) and Bougainvillea spectabilis. Three treatments were used: Phytosaneb-020, Pacha a chemical insecticide and aqueous solution (distilled water) as a negative control. A volume of 1.5 mL for an area of ​​56.72 cm2 corresponding to the area of ​​a Petri dish, used for each treatment. Populations of Maconellicoccus hirsutus were carefully collected from bougainvillea leaves and roses. Pacha gave the highest mortality percentage for direct toxicity by contact (98.3± 2.89%) followed by Saneb-020 (93.3 ± 7.64%). The negative control, distilled water, was not effective against the insects. No death was observed (0%). The repellency effect assay revealed a repellent activity of 80% ± 20 for Saneb-20. Distilled water gave the best avoidance effect (86.7±11.6%) pointing out the fact that Mealybug Planococcus ficus doesn’t support the presence of water. Pasha exhibited low repellency effect on Mealybug Planococcus ficus (46.7±41.6%). Further investigations on different pests are strongly suggested and encouraged to improve the effectiveness of this biopesticide.

Multiple Effects of Nitrogen Fertilization on Grape Vegetative Growth, Berry Quality and Pest Development in Mediterranean Vineyards

Nitrogen is a key macronutrient for the quantitative and qualitative yield of grapes; in addition, it influences the development and reproduction of grape pests. The multiple effects of different nitrogen rates were investigated on the red berry cultivar ‘Carignano’ and the grape pest Planococcus ficus in a two-year field trial. Different amounts of ammonium nitrate were compared: 0, 80 and 160 Units ha−1 for mineral nitrogen. The amount of nitrogen fertilization supplied influenced the nitrogen status of vines and increased the pruning weight and leaf area, as well as the overall grape yield, by increasing the cluster weight. However, doubling the nitrogen rate did not generally increase the vegetative and productive parameters of grapevines. At harvest, nitrogen supply did not influence the anthocyanin content, tritatable acidity, and soluble solids, although the latter parameter showed a clear, yet not significant, decreasing trend. Planococcus ficus exhibited higher fecundity, survival and shorter development time on grapevines provided with nitrogen, whereas its fertility was unaffected by nitrogen fertilization. Ultimately, nitrogen had a direct and positive effect on grape yield and vine mealybug development, highlighting the importance of integrated cultural and pest control practices to promote grape production.

Quantifying Planococcus ficus (Hemiptera: Pseudococcidae) Invasion in Northern California Vineyards to Inform Management Strategy

The spread and impact of invasive species in exotic ranges can be mitigated by increased understanding of pest invasion dynamics. Here, we used geospatial analyses and habitat suitability modeling to characterize the invasion of an important vineyard pest, vine mealybug (Planococcus ficus Signoret, Hemiptera: Pseudococcidae), using nearly 15,000 trapping records from throughout Napa County, California, between 2012 and 2017. Spatial autocorrelation among P. ficus detections was strongest at distances of ~250 m and detectable at regional scales (up to 40 km), estimates of the rate and directionality of spread were highly idiosyncratic, and P. ficus detection hotspots were spatiotemporally dynamic. Generalized linear model, boosted regression tree, and random forest modeling methods performed well in predicting habitat suitability for P. ficus. The most important predictors of P. ficus occurrence were a positive effect of precipitation in the driest month, and negative effects of elevation and distance to nearest winery. Our results indicate that 250-m quarantine and treatment zones around P. ficus detections are likely sufficient to encompass most local establishment and spread, and that implementing localized regulatory procedures may limit inadvertent P. ficus spread via anthropogenic pathways. Finally, surveys of P. ficus presence at >300 vineyard sites validated that habitat suitability estimates were significantly and positively associated with P. ficus frequency of occurrence. Our findings indicate that habitat suitability predictions may offer a robust tool for identifying areas in the study region at risk to future P. ficus invasion and prioritizing locations for early detection and preventative management efforts.

Development of a Mating Disruption Program for a Mealybug, Planococcus ficus, in Vineyards

The vine mealybug (VMB), Planococcus ficus (Hemiptera: Pseudococcidae), is a key insect pest of vineyards, and improvements in sustainable control of this pest are needed to meet increasing consumer demand for organically farmed products. One promising option is mating disruption. In a series of experiments conducted from 2004 to 2007, we tested the effects of mating disruption on trap captures of Pl. ficus males in pheromone-baited traps, on Pl. ficus numbers and age structure on vines, and on damage to grape clusters. From 2004 to 2005, the effects of dispenser load (mg active ingredient per dispenser) were also assessed, and dispensers were compared to a flowable formulation. Across all trials, mating disruption consistently reduced pheromone trap captures and often reduced mealybug numbers on vines and/or crop damage, regardless of the pheromone dose that was applied. Reductions in Pl. ficus densities in mating disruption plots were not accompanied by clear effects on mealybug population age structure; however, production of non-viable ovisacs by unmated females may have obscured differences in proportional representation of ovisacs. Pheromone trap captures were never lowered to zero (often called trap shut down), possibly because trials were conducted in vineyards with unusually high Pl. ficus densities. Trap-capture patterns in both treated and control plots commonly began low in April–May, increased in mid-July or August, and often decreased in September–October when post-harvest insecticides were applied. During the four-year trial, the release rate from plastic sachet dispensers was improved by industry cooperators as pheromone was released too quickly (2004) or not completely released during the season (2005–2006). The flowable formulation performed slightly better than dispensers at the same application dose. Results over all years suggest season-long coverage or late-season coverage may be as or more important than dose per hectare. Development of a dispenser with optimized season-long pheromone emission or targeted seasonal periods should be a future goal.

Planococcus ficus. [Distribution map].

A new distribution map is provided for Planococcus ficus (Signoret). Hemiptera: Pseudococcidae. Main hosts: grapevine (Vitis vinifera), fig (Ficus carica). Information is given on the geographical distribution in Europe (Albania, Bulgaria, Croatia, Cyprus, France, Corsica, Greece, Crete, Italy, Sardinia, Sicily, Malta, Portugal, Azores, Madeira, Slovenia, Spain, Canary Islands, Ukraine), Asia (Azerbaijan, Georgia, India, Maharashtra, Iran, Iraq, Israel, Jordan, Lebanon, Malaysia, Pakistan, Saudi Arabia, Syria, Turkey, Turkmenistan, Yemen), Africa (Cote d'Ivoire, Egypt, Libya, Mauritius, South Africa, Tunisia), North America (Mexico, USA, California), Central America & Caribbean (Dominican Republic, Haiti, Trinidad and Tobago), South America (Argentina, Brazil, Rio Grande do Sul, Chile, Peru, Uruguay).