Fruit Damage Patterns Caused by Ovipositing Females ofConotrachelus dimidiatus(Coleoptera: Curculionidae) in Guava Trees

Abstract

We evaluated the damage patterns produced by females of the guava weevilConotrachelus dimidiatusChampion, 1904 (Coleoptera: Curculionidae), according to the position of the damaged fruit in guava treesPsidium guajavaL. in Calvillo, Aguascalientes, Mexico. The trees were subdivided in eight zones, and during one year the level of fruit lesions due to oviposition was registered. Results showed a higher level of damage in the upper and external zone of the trees(P≤.05). We found no significant differences in damage between the four cardinal points(P≥.05). During the year, the level of damage was recorded and was higher in the months of August and September(P≤.05)associated with rainfall (0.86,P=.06) and increase in temperature (0.84,P=.03). The most susceptible fruits were in the size range of 2.1–4.0 cm (polar diameter). The information from this study will be used to design and establish effective control strategies for the guava weevil, taking into account location of the most susceptible fruits, seasonality of the pest, and the abiotic factors.

Weevil Borers in Tropical Fruit Crops: Importance, Biology and Management

“…In the orchards, control is based considering the behavior and biology of the insect, according [22,33] to the presence of adults they have relationship with the rainy season, which are the ones to initiate the damage and infestation of fruit. Based on sampling, using a network under the tree before the start of rainy season, the detection of an adult/tree and observation of fruits with oviposition, applications of chemical insecticides, repellents and entomopathogenic are needed.…”

“…Damaged fruits develop kidney shaped, mature and fall prematurely ( Figure 5). In Calvillo, Aguascalientes, Mexico, the infestation of fruits averages 37.4%, which is higher in the lower portion of the tree and during the rainy season, the fruits are more susceptible when they are young, developing two to four cm of polar diameter [33]. The larvae feed the pulp, causing destruction and blackening of this and seeds ( Figure 6).…”

Emergent and Possible Invasive Pest Species of Weevils in Mexico

“…Guava fruits are damaged when females oviposit into the mesocarp and larvae penetrate the interior of the fruit, blackening the mesocarp and seeds, and causing fermentation and fruit yellowing (Aragón et al 2015). The main damage occurs in the upper and inside zone of infested trees (Tafoya et al 2010). When fruit is absent, adults often feed on terminal buds and affect terminal growth (personal observation).…”

Volatile compounds in different parts of the fruit Psidium guajava L. cv. “Media China” identified at distinct phenological stages using HS‐SPME‐GC‐QTOF/MS

“…As a result of the larval activity, fruits putrefy and mature prematurely . Furthermore, the larval excrement ferments the fruit, which renders the guava unfit for industrial use or human and animal consumption …”

“…22 Furthermore, the larval excrement ferments the fruit, which renders the guava unfit for industrial use or human and animal consumption. 23 Maturity stage at the time of harvest determines the quality and storage life of guava fruits. Authors have described three and four stages, or five phases depending on the time after flowering in 30-day intervals.…”