Deep Convolutional Neural Networks for Tea Tree Pest Recognition and Diagnosis

Due to the benefits of convolutional neural networks (CNNs) in image classification, they have been extensively used in the computerized classification and focus of crop pests. The intention of the current find out about is to advance a deep convolutional neural network to mechanically identify 14 species of tea pests that possess symmetry properties. (1) As there are not enough tea pests images in the network to train the deep convolutional neural network, we proposes to classify tea pests images by fine-tuning the VGGNET-16 deep convolutional neural network. (2) Through comparison with traditional machine learning algorithms Support Vector Machine (SVM) and Multi-Layer Perceptron (MLP), the performance of our method is evaluated (3) The three methods can identify tea tree pests well: the proposed convolutional neural network classification has accuracy up to 97.75%, while MLP and SVM have accuracies of 76.07% and 68.81%, respectively. Our proposed method performs the best of the assessed recognition algorithms. The experimental results also show that the fine-tuning method is a very powerful and efficient tool for small datasets in practical problems.

Evaluation of Botanicals for Management of Piercing–Sucking Pests and the Effect on Beneficial Arthropod Populations in Tea Trees Camellia sinensis (L.) O. Kuntze (Theaceae)

The tea green leafhopper Empoasca onukii Matsuda (Hemiptera: Cicadellidae), the orange spiny whitefly, Aleurocanthus spiniferus (Quaintanca) (Hemiptera: Aleyrodidae), and the green plant bugs Apolygus lucorum Meyer-Dür (Hemiptera: Miridae) are the important piercing–sucking herbivores in tea trees Camellia sinensis (L.) O. Kuntze (Theaceae). The goal of this study was to evaluate the laboratory toxicities and field control efficacies of botanical insecticides including matrine, azadirachtin, veratrine, and pyrethrin to three tea pests. Via leaf-dip bioassay, toxicity tests with botanical insecticides indicated that there were significant differences between the LC50 values for botanical insecticides within the same insect species. Matrine had the highest toxicity to E. onukii, A. spiniferus, and A. lucorum with the LC50 values of 2.35, 13.10, and 44.88 mg/liter, respectively. Field tests showed that, among four botanical insecticides, matrine at dose of 9 g a.i. ha−1 can significantly reduce the numbers of E. onukii and A. spiniferus and the infestation of A. lucorum on the tea plants. Furthermore, botanical insecticides matrine and azadirachtin had no obvious influence on the coccinellids, spiders, and parasitoids densities in tea plantations. The results of this study indicated that use of botanical insecticides, such as matrine, has the potential to manipulate the population of E. onukii, A. spiniferus, and A. lucorum and will be an effective and environmentally compatible strategy for the control of tea pests.

Diversity and density of tea pests in the tea gardens of Manipur

<p>Twenty one species of tea pests have been recorded for the first time from the tea gardens of Manipur which include twelve species of cutting and chewing pests, seven species of sucking pests, a stem borer and a leaf miner. Among them, red spider mite, (<em>Oligonychus coffeae</em>), leaf roller, (<em>Caloptilia theivora</em>), thrips (<em>Mycterothrips setiventris</em>) and aphid, (<em>Toxoptera aurantii</em>) were categorised as important pests and the rest as minor pests based on the observations carried out for one pruning cycle during 2010 to 2013. Field studies had shown that red spider mite (RSM) infested the tea plants all through the year with peak density of 16 mites per leaf per bush in April, whereas occurrence of thrips had been recorded with maximum abundance of 6 thrips per leaf per bush during October. On the other hand, tea aphids infested the plant from March to October with maximum of 200 individuals per 5 cm length of tea shoot in September. The stem borer, <em>Zeuzera coffeae </em>was noticed during March, April and September with an average density of 9.5 borers per 40 bushes. Among the foliage folders, leaf roller was predominant over flush worm and tea tortrix. Occurrence of leaf rolls was noticed from June to November with maximum incidence of 6 larvae per bush in October, but flushworms and tortrix were abundant even in April with the mean of 3 larvae per infested tea bush. Based on the above observation, a pest calendar was prepared for the tea pests of Manipur for planning pest control measures. Besides, 16 species of natural enemies attacking the tea pests are also reported in this article.</p>