Most crops have been dramatically altered from their wild ancestors with the primary goal of increasing harvestable yield. A long-held hypothesis is that increased allocation to yield has reduced ...plant investment in defence and resulted in crops that are highly susceptible to pests. However, clear demonstrations of these trade-offs have been elusive due to the many selective pressures that occur concurrently during crop domestication.
To provide a robust test of whether increased allocation to yield can alter plant investment in defence, this study examined fruit chemical defence traits and herbivore resistance across 52 wild and 56 domesticated genotypes of apples that vary >26-fold in fruit size. Ninety-six phenolic metabolites were quantified in apple skin, pulp and seeds, and resistance to the codling moth was assessed with a series of bioassays.
The results show that wild apples have higher total phenolic concentrations and a higher diversity of metabolites than domesticated apples in skin, pulp and seeds. A negative phenotypic relationship between fruit size and phenolics indicates that this pattern is driven in part by allocation-based trade-offs between yield and defence. There were no clear differences in codling moth performance between wild and domesticated apples and no overall effects of total phenolic concentration on codling moth performance, but the results did show that codling moth resistance was increased in apples with higher phenolic diversity. The concentrations of a few individual compounds (primarily flavan-3-ols) also correlated with increased resistance, primarily driven by a reduction in pupal mass of female moths.
The negative phenotypic relationship between fruit size and phenolic content, observed across a large number of wild and domesticated genotypes, supports the hypothesis of yield-defence trade-offs in crops. However, the limited effects of phenolics on codling moth highlight the complexity of consequences that domestication has for plant-herbivore interactions. Continued studies of crop domestication can further our understanding of the multiple trade-offs involved in plant defence, while simultaneously leading to novel discoveries that can improve the sustainability of crop production.
Insect olfaction is vital for foraging, mating, host-seeking, and avoidance of predators/pathogens. In insects, odorant binding proteins (OBPs) are involved in transporting hydrophobic odor molecules ...from the external environment to receptor neurons. The codling moth,
, one of the most destructive insect fruit pests, causes enormous economic losses. However, little is known about the number, variety, gains and losses, and evolution of
genes in
. Here we report the identification of 40
in
, most (75%) of which are classic
, using genomic and transcriptomic analyses. Two
genes were lost in
relative to possible distant ancestor in Lepidoptera lineage based on an analysis of gene gains and losses. The phylogenetic tree and chromosome location showed that the expansion of
genes mainly resulted from tandem duplications, as the
gene was duplicated twice along with loss of
. Two positive selection sites of the
gene were identified while other
genes evolved under purifying selection. Our results provide fundamental knowledge of
genes allowing further study of their function in
.
•Vibro-acoustic emission was investigated for detection of codling moth in apples.•Classifiers with matched filtering shows better performance as compared to unfiltered method.•Decision tree and ...ensemble classifiers show better performance as compared to kNN, LDA, and NB.•Heat stimulation method improved classification performance.
Codling moth (CM) is the most devastating global pest of apples with a huge potential impact on the post-harvest quality and yield of the product. Due to the small size of its larvae and potentially hidden behavior, simple visual inspection is ill-suited for accurate infestation detection. The characteristic vibro-acoustic signals of multiple behaviors of CM larvae such as chewing and boring were identified in a previous study. In this study, two different approaches were proposed to build on this previous work: multi-domain feature extraction with machine learning to show basic classification potential, and matched filter-aided classification to show the effects of preprocessing using the larval behavior templates. Additionally, low-intensity heat stimulation was applied to improve classification results by increasing the larvae’s hidden activity rate. The results indicated that the first approach led to accuracies as high as 97.47 % for an acoustic signal duration of 10 s, with heat stimulation improving classification rates to 98.96 % for the same interval. Finally, the matched filter-aided classification approach improved upon the heat stimulated results even further to obtain a 100 % accuracy on classifying the test set for a signal duration of 5 s. These findings suggest that the vibro-acoustic technique can be an adaptable tool for detecting CM infestation in apples and improve post-harvest classification quality in fruit.
Apple growers have pursued the use of exclusion netting to reduce pesticide inputs and maintain control of codling moth.
It is uncertain if these nets provide a physical or behavioural behaviour, and ...if they prevent codling moth establishment.
To address this, we conducted field trials testing the ability of commercial netting to exclude codling moth using small (3 trees) and large (48 trees) cages. Experiments were conducted to evaluate both the permeability by releasing marked sterile moths either inside or outside the small cages, and the establishment of wild codling moth in the large cages.
Results from the small cage study showed that netting reduced codling moth movement out of the netted plots, but virtually prevented codling moth dispersal into the plots. Codling moth capture inside the large cage plots was significantly less than in uncaged plots, but no differences were found in codling moth damage at harvest.
These results indicate that the netting is physically permeable to codling moth adults; however, it acts as a behavioural barrier to moth immigration. These outcomes agree with existing literature that net enclosures can provide a non‐insecticidal tool to improve codling moth management, although it may not be a stand‐alone technique.
Organic farming is an essential component of sustainable agriculture that can help maintain biodiversity in agricultural landscapes, providing benefits for both human well-being and environmental ...conservation. Recent studies have highlighted the vital role of insectivorous bats in farmland ecosystems in controlling pest insect populations. Our research focuses on the direct economic value of bat insectivory in woody crops, specifically in apple orchards affected by the codling moth Cydia pomonella. We conducted an exclusion experiment followed by an economic evaluation to estimate the impact of bat insectivory on crop damage and economic savings. Our results demonstrate that the presence of bats in apple orchards can significantly reduce the damage caused by C. pomonella, resulting in a 32.1% reduction in affected apple trees and a 50% reduction in the total weight of damaged apples per tree. This translates to estimated economic savings of 551 €/ha/y by reducing the need for insecticide applications and, consequently, minimizing the negative impacts of such chemicals on the environment and human health. Moreover, the presence of bats can lead to higher crop yields and protect the quality of the product, resulting in higher profits for farmers. Our findings highlight the critical role of bats in maintaining ecosystem services and provide valuable information for the sustainable management of farmland ecosystems.
The egg parasitpoids
Trichogrammadanausicida
(Nagaraja) and
Trichogrammacacaeciae
(Marchal) (Hymenoptera: Trichogrammatidae), are reported for the first time in Israel. Moreover, our discovery of
...T.danausicida
is the first report of this parasitoid species outside of India. The occurrence of those trichogrammatids was first discovered and documented in May 2016 during a survey of egg parasitoids of the False codling moth
Thaumatotibialeucotreta
(Lepidoptera: Tortricidae). The field survey was conducted on castor bean fruits (
Ricinuscommunis
) in the Israeli central coastal plain. The identity of the parasitoids was revealed by means of sequencing a portion of the cytochrome oxidase I gene (COI) of the studied parasitoids.
Thaumatotibia leucotreta (Lepidoptera, Tortricidae) is one of many economically important insect pests for which no complete mitogenome sequence is available. The complete mitochondrial sequences for ...this species and other key pests could assist in the development of novel molecular techniques, such as enabling the identification of population‐specific markers which could assist in improved monitoring of populations. The objective of this study was to determine whether NGS datasets generated for entomopathogenic viruses contain reads originating from host mitochondrial DNA. A total of 28 NGS datasets generated for the baculovirus Cryptophlebia leucotreta granulovirus (CrleGV) were analysed in this study. Three datasets contained sufficient reads providing adequate coverage for the assembly of complete mitogenomes. All 13 protein‐coding genes, 22 tRNAs and both rRNAs present in the mitogenomes of other species within the Grapholitini tribe, were identified. Phylogenetic analysis of the mitogenomes at both an intrafamilial and interspecies level grouped the sequences within the Olethreutinae and T. leucotreta clades, respectively. Analysis of single nucleotide variations (SNVs) between each T. leucotreta sequence indicated up to 75 differences across the mitogenome. The methodology used in this study could be expanded to other baculovirus NGS datasets enabling the generation of novel lepidopteran mitogenome sequences.
Mitogenomic data were extracted from multiple pre‐existing baculovirus NGS datasets.
Three complete mitogenome sequences were assembled, annotated and analysed for the lepidopteran pest Thaumatotibia leucotreta.
The application of this technique could enable the determination of mitogenome sequences for other important lepidopteran pests.
Quince (Cydonia oblonga Miller) is one of the common hosts of the codling moth, Cydia pomonella L. Knowledge of the chemical ecology of codling moth is based on its behaviour against apples and pears ...but not quince. Here, we present a laboratory study on olfactometry and oviposition behavior preference of mated females and neonate larvae of codling moth against four quince cultivars. Oviposition of mated females was evaluated on dual‐choice test, whereas olfactometry response was evaluated in a Y‐tube olfactometer. Neonate larvae were evaluated in a dual‐choice test between pieces of fruit of quince cultivars in pairwise comparisons. In the Y‐tube olfactometer assay, mated females always responded positively to the fruit‐scented arm to quince fruit volatiles. Smyrna and Champion cultivars showed significant differences in the time that mated females spent in the fruit‐scented arm. In the oviposition assay, all pairwise comparisons showed significant differences in the number of the eggs laid, with Smyrna and Champion being the cultivars most preferred. No significant differences were detected in dual choice of neonate larvae. All comparisons elicited the behaviour of contacting the fruit source. Based on the potential emission of recognized kairomones and the results found here, cultivars Smyrna and Champion are suggested as cultivars most susceptible to codling moth infestation.
•Exclusion, sterilisation and disruption offer a different paradigm in pest management.•Exclusion (netting) can be used in the most diverse settings.•Sterile insect release (SIT) is the most ...selective but also costly.•Mating disruption is the easiest to implement at the farm level.
Because of their perennial nature, orchards harbor one of the most complex ecosystems in agriculture. Nevertheless, crop protection programs still mainly focus on pesticides (synthetic or organic-approved) to prevent or limit the action of so-called noxious species in these systems. Killing agents represent the dominant paradigm and have been used in agriculture for decades. This paper synthesizes the available literature about the other approaches, more suited to organic farming, which recognize that the radicalness of killing is not necessary to prevent crop losses. Exclusion barriers represent one of the most readily available means of protecting the crop that way, but other behavior-based techniques have been developed, such as sterile insect technique and mating disruption. While there are many other possibilities, these are the three approaches that are currently getting the most interest in tree fruit production, due to ecological and agronomical characteristics, some of which will be detailed in this review.
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