Variation in fruit traits and infestation ratios in natural sweet chestnut (Castanea sativa) populations under chestnut weevil (Curculio elephas) damage

Abstract

Sweet chestnut (Castanea sativa Mill.) is one of the most important species in agro-forestry and horticulture. Turkey is an important C. sativa gene centre and fruit production region. The present study aimed to measure the variations in fruit width, length, thickness and weight in four different natural C. sativa populations in Turkey and determine the loss of fruit traits due to damage by chestnut weevil (Curculio elephas (Gyllenhal, 1836)) (Coleoptera: Curculionidae). Fruits were collected from four populations (Istanbul-Bahçeköy, Çanakkale-Bayramiç, Balıkesir-Erdek and Bursa-Uludağ) of phenotypically healthy sweet chestnut trees, measurements were taken, and the fruits were classified into those damaged by C. elephas and those not. Analysis revealed significant differences among and within the populations in all fruit traits, and between the sound and damaged fruits, with the average fruit width, length, thickness and weight being 24.8 mm, 23.1 mm, 15.3 mm and 3.4 g, respectively. Bursa-Uludağ population had the highest healthy fruit ratio (70%), with some individuals in the population yielding healthy fruits at ratios > 90%. In the Balıkesir-Erdek population, however, where the percentage of damaged fruits was the highest (54%), it was determined that some trees suffered more than 90% damage in contrast to the Bursa-Uludağ population. In the fruits infested by C. elephas, the approximate percentages of loss in fruit width, length, thickness and weight were 6, 4, 7 and 30%, respectively. The fruit weight loss percentages varied between 25% and 32% among the populations.

Brown Rot Caused by Gnomoniopsis smithogilvyi (syn. Gnomoniopsis castaneae) at the Level of the Chestnut Tree (Castanea sativa Mill.)

“…Furthermore, on average, 56.3 and 27.8% of the infested fruits contain one or two immatures (eggs and larvae) [7], showing the frequent presence of this chestnut weevil in the groves. More recently, when analyzing the loss of fruit traits due to damage by this weevil in four populations of healthy sweet chestnut trees in Turkey, Caliskan et al [8] verified that the fruit weight loss percentages varied between 25% and 32%, demonstrating again the production and economic losses that this pest can cause to producers. Cydia splendana Hübner (Lepidoptera: Tortricidae) is another pest that chestnut producers face because the larvae feed on the fruits, reducing their quality and economic value.…”

Ceviz kurdu, Alcidodes porrectirostris Marshal (Coleoptera: Curculionidae)'nin laboratuvar koşulları altında biyonomisi ve Hindistan'ın Keşmir vadisinde Juglans regia'daki (L.) zarar derecesi hakkında güncellenmiş veri

“…Asian walnut moth, Garella musculana Erschoff is also a serious pest of J. regia (Bostanci et al 2021, EPPO 2019, Khan et al 2023) and J. nigra (Bostanci et al 2019). In the plethora of insect pests affecting the walnut trees in Jammu and Kashmir (J&K), Walnut weevil, Alcidiodes porrectirostris Marshal (Coleoptera: Curculionidae) is one of the most destructive pests causing about 36.7% fruit damage (Mir and Wani 2005) and in some situations up to 90% output loss (Caliskan et al 2020). The walnut weevil is a mediumsized pest with characteristics of the Mecysolobini tribe of the weevil family Curculionidae (Bhagat 2017).…”