Article History Keywords Scrobipalpa Ocellatella, Spodoptera Littoralis, Spodptera Exigua, Ecdysone Agonists, Alternatives, Arth
Total Page:16
File Type:pdf, Size:1020Kb
Egypt. J. Plant Prot. Res. Inst. (2020), 3 (1): 290 - 299 Egyptian Journal of Plant Protection Research Institute www.ejppri.eg.net Field evaluation of methoxyfenozide and chromafenozide, ecdysone agonists against cotton leaf worm, sugar beet moth and preservation their predators Amira, SH. M. Ibrahim Economic Entomology Dept., Fac. Agric., Kafr El-Sheikh Univ., Egypt. ARTICLE INFO Abstract: Article History Due to the significant economic losses of the sugar beet crop Received: 1/ 2 / 2020 caused by the cotton leaf worm Spodoptera sp. (littoralis and exigua) Accepted: 29/ 3/2020 and the sugar beet moth Scrobipalpa ocellatella (Boys.) (Lepidoptera : Keywords Gelechiidae), as well as the desire to reduce the use of traditional Scrobipalpa ocellatella, insecticides for their harms, this study was conducted during seasons; Spodoptera littoralis, 2017/2018 and 2018/2019 at shenno village, Kafr El-Sheikh Spodptera exigua, Governorate .The aim was to evaluate alternatives to traditional ecdysone agonists, insecticides represented by five ecdysone agonists. It also assesses its alternatives, arthropod, role in maintaining the presence of arthropod predators associated with predators and sugar these pests in the field. Results showed that the tested ecdysone beet. agonists and the tested insecticides were similar in reducing the number of Spodoptera sp. larvae. The all tested insecticides induced above 92% reduction in Spodoptera sp. larvae number in the both study seasons. As for the arthropod predators associated with Spodoptera sp., the maximum overall mean reduction was 31.59% and 11.57% during the first and second seasons respectively Compared to traditional insecticides (99.38% and 98.68% in 2017/2018 and 2018/2019 seasons respectively). Ascendancy reducing the number of S. ocellatella larvae, overall mean of reductions to all tested insecticides took the same trend. They caused above 87% reduction in S. ocellatella larvae numbers. Concerning the arthropod predators numbers associated with S. ocellatella, the maximum overall mean of reduction caused by the tested ecdysone agonists were 12.41% and 14.40% in the first and second seasons respectively. While, that recorded when using traditional insecticides 99.20%in 2017/2018 season and 99.54% in 2018/2019. Introduction Sugar beet Beta vulgaris L. Saied, 1998; Bazazo, 2005; Saleh et (Family : Chenopodiaceae) attacks by al.,2009; Bazazo, 2010; El–Dessouki, several insect species beginning from 2014; Bazazo et al., 2016; Khalifa 2018 seed germination up to harvest (Abo– and El-Dessouki, 2019). These insect 290 Ibrahim, 2020 pests proved to reduce the crop quality Growth regulators (IERs) are bio-rational (Sugar Percent) and quantity (roots insecticides with novel modes of action weight per feddan) (Shalaby, 2001; which disrupt the physiology and Bazazo, 2010; Shalaby et al., 2011; development of the target pest, such Rashed, 2017 and Abbas, 2018). compounds tend to be selective and Lepidopteran pests of sugar beet cause generally less toxic to natural enemies severe yield reduction in most growing than conventional insecticides (Gurr et areas of the world (Jafari et al., 2009). al., 1999). Ecdysone agonists are one of The cotton leaf worms, Spodoptera the most important groups of IGRs, and littoralis Boisd and Spodoptera exigua widely used against many lepidopteran Hub. (Lepidoptera: Noctuidae) and the pests. Methoxfenozide and beet moth Scrobipalpa ocellatella (Boys.) Chromafenozide are important members (Lepidoptera: Gelechiidae) are of ecdysone agonist they highly specific destructive insects and causing high to lepidopteran pests all over the world economic losses to sugar beet crop in (Pineda et al., 2009). They were reported Egypt. to be safer for natural enemies than Severe infestation of sugar beet conventional products (Schneider et al., with S. cellatella larvae was caused 2008). They favorable eco-toxicological significant reductions of 38.20 and profile and short period of persistence in 52.40% in root weight and sugar the environment mad their good choice percentages, respectively (Abo- for integrated pest management (IPM) Saied,1987). Bassyouny et al. (1991) programs in various crops (Pineda et al., found that the younger plants were highly 2006). infested with cotton leaf worms, the Therefore, the current study was greater damage was caused in both sugar conducted for field evaluation of the five beet leaves and roots, consequently a ecdysone agonists efficiency considerable reduction in sugar (methoxyfenozide and chromafenozide) percentages. Also, Mesbah (2000) in reducing the number of cotton leaf concluded that one larva of S.littoralis worm and sugar beet moth larvae. In consumed 183.6 cm2 of sugar beet leaf addition to assess their role in tissues throughout the entire larval stage, maintaining the presence of the Causing large bare batches. All the associated predators compared to farmers spray the conventional conventional ones. insecticides in controlling these insects. Materials and methods But, the intensive use of conventional The current study was conducted insecticides led to several important during two successive seasons; drastic problems, i.e. environmental 2017/2018 and 2018/2019. Farida pollution, sedtruction of the natural cultivar was planted at Shenno village, enemies and incidence insect resistance Kafr El-Sheikh Governorate. The early to these insecticides (Awad et al., 2014). plantation was sown on 5th August and Over the past four decades, efforts the late plantation was sown on 30th have been made to develop novel October in both seasons. Five ecdyson insecticides with selective properties that agonists and five traditional comparison are designed to act on specific insecticides are listed in Table (1) were biochemical sites or physiological used. Each treatment was replicated four processes of the target pest. Insect times (10 x 4 = 40 plots) in randomized 291 Egypt. J. Plant Prot. Res. Inst. (2020), 3 (1): 290 - 299 block design. Each plot was measured examination was done three, seven and 42m2, in additional to four plots as 10 days after tested ecdysone agonists control. The experimental plots were application. While it was achieved one, separated from each other by untreated seven and 10 days after traditional tested belts to avoid spray drift. Each sample insecticides application according to was consisted of 10 plants/plot (40 Anonymous (2019). Also, arthropod plants/ treatment). The primary fauna of predators was sampled using examination was done before treatment. visual examination and sweep net. In The treatments were applied on 5th each replicate, ten single strokes were September at the early plantation and on made at diagonal direction (Kandil et al., 10th March at the late plantation against 1991). The Reduction in the Spodoptera Spodoptera sp. and S. ocellatella larvae, sp., S. ocellatella larvae and associated respectively in both seasons. Knapsac arthropod predators number were sprayer (20 L Volume) was used in calculated by Henderson and Tilton applying the treatments. Number of formula (1955). Spodoptera sp and S. ocellatella larvae Differences between mean numbers of was simultaneously counted at the early the Spodoptera sp. and S. ocellatella and the late plantations respectively. The larvae after the tenth day of treatment associated arthropod predators were were analyzed using Duncan test (1955). distinguished and accounted. The visual Table (1): List of the tested insecticides and their rats per feddan. Insecticide Category Rate Common name Trade name Methoxyfenozide Raner 24% Sc Ecdysone agonist 75 cm3 /fed. Methoxyfenozide Abhold 36% Ec Ecdysone agonist 125 cm3 /fed. Chromafenozide Ferto 5% Sc Ecdysone agonist 400 cm3 /fed. Methoxyfenozide Xtreme 36% Ec Ecdysone agonist 125 cm3 /fed. Methoxyfenozide Methobiet 24% SC Ecdysone agonist 75 cm3 /fed. Chlorpyrifos Dora 48% EC Conventional 1L./fed. Carbosulfan Marshal 20% Ec Conventional 250 cm3 /fed. Chlorfenapyr Fanty plus 36% EC Conventional 90 cm3 /fed. Methomyl Diracomel 90% Sp Conventional 300 gm /fed. Pyridalyl Pelo 5% Ec Conventional 100 cm3 /fed. Results and discussion season, over all mean of reduction 1. Effects on Spodoptera sp. larvae and percentages were 95.87, 95.93, 95.53, their associated arthropod predators: 94.34 and 95.70%, respectively. Data shown in Table (2) indicate Concerning the conventional insecticides, that the reduction percentages for the five dora, marshal, fanty plus, diracomel and ecdysone agonists insecticides; raner, pelo recorded high reduction percentages abhold, ferto, xtreme and methobiet in after the first, seventh and tenth days of Spodoptera sp. larvae number were close. treatment. Overall mean of reduction High reduction percentages were percentages was 97.15, 95.61, 95.44, achieved after the third, seventh and tenth 95.30 and 95.61%, respectively in days of treatment. Overall mean of 2017/2018 season. Also, it was 95.34, reduction percentages in Spodoptera sp. 96.09, 97.56, 97.38 and 97.76%, larvae number were 92.04, 93.29, 94.01, respectively in 2018/2019 season. 93.78 and 94.12%, respectively in Overall mean of reductions to the 2017/2018 season. As well in 2018/2019 all tested insecticides ranged between 292 Ibrahim, 2020 92.04 – 97.15% in the first season and to 31.59% and 10.84 to 11.57% during 94.34 – 97.76% in the second season. the first and second seasons respectively. This means that the all tested insecticides While the treatment with conventional induced above > 92% reduction in insecticides led to a high reduction