Bio-rationale Management of Tuta absoluta Meyrick (Gelechiidae: Lepidoptera) using some Sudanese Tomato Accessions and Extracts of some Botanicals

Abstract

The tomato fruit borer, Tuta absoluta (Meyrick) (lipodopetra: Gelechiidae) ,was the most serious incest pest of tomato during the last decade threatening its production all around the world. The pest is highly aggressive was capabilities to invade new territories, affecting tomato and many other host plants. Different management procedure were adopted in many countries, Including the use of insecticides to control T.absoluta.Reliance on chemicals to control insect pest is hazardous to human, animal, beneficial insects and environment; also it generates insect resistance and leads to resurge of non-harmful ones. This study was initiated to mitigate the damage caused by T absoluta, look for alternative bio-rationale eco-friendly management tactics, benefited from the nature through assessment of the possibility of tolerance/ resistance of some tomato local accessions and assessing the effect of extracts of some botanicals on larval mortality. Twelve Sudanese tomato accessions provided by Plant Genetic Resource Centre of ARC (Wad Medani, Sudan) were evaluated for their resistance to T. absoluta in field experiments carried for three winter seasons,2017/18,2018/19 and 2019/20, in the farm of Kassala an Gash Research Station, in Takroof area, Kassala, Sudan. The experiments were arranged in a randomized complete block design (RCBD) with three replicates. Parameters include, number of active mnes, percentage of infested plants, percentage of infested fruits, yield, fruit diameters, days to 50% flowering fruit. Total soluble solid and number of trichomes of leaves were used as indicators for the susceptibility, tolerance or resistance of the tomato accessions. Chemical constituents; Lycopene, Tannin, Ascorbic acid and carotene of different test accessions and hybrids were determined using Elico SL-150 UV-Vis spectrometer device ,applying different analysis standard protocol.The effects of oil extracts of Neem, Azadirchta indica Ajuss, aqueous extracts of Datura, Daura stramonium and Periwenkle, Venca roseaL, were evaluated against the infestation of T. absolua and yield of tomato in randomized complete block design field trials.The results of evaluation of accessions and hybrids of tomatofor resistance to T. absoluta showed high significant difference (pr>f<0001) for the percentage of infested plants/plot, mean number of active mines/plot percentage of infestedfruits/plots, Total Soluble Solid (TSS), fruit diameter (cm2) and yield of tomato (Ton/Ha) for the first , second and third seasons, combined results of the three season and the interaction between seasons and accessions and hybrids. Also High significant difference was revealed between accessions and hybrids on the number of trichomes/cm2of leaves and content of Lycopene, Tannin, Carotene and Ascorbic acid. Accessions HSD6071 and HSD14358 recorded the least percentage of infested leaves/plot, least number of active mines/plot and least percentage of infested fruits/plot .The same three accessions obtained the highest TSS, highest fruit diameters (cm) and highest yield (Ton/Ha) and highest number of trichomes/cm2 of leaves. For the chemical constituents of accessions HSD14358 obtained the highest content of Tannin followed by HSD11429 and HSD6069. Lycopene content was found in high percentage in HSD4420, HSD4419 and HSD6639 while HSD6069, an HSD6639contained the highest percentage of Carotene.On other hand, the content of Ascorbic acid was found greatest in HSD4419, HSD10665.TSS was found correlated highly negative with the percentage of infested leaves/plot (.0.82977,<.0001), number of mines/plot (-0.84764,<.0001) and percentage of infested fruits/pot (-0.81465, <.0001) and correlated highly positive with yield (0.64773, <.0001) Tannin correlated moderately negative(0.5409, <.0001) with the percentage of infested plant/plot and correlated weekly negative with the number of the active mines/plot and correlative (-0.5409, <,001) with the number active mine /plot aswell as percentage of infesed plant /plot(-0.5409, <,001) and mean number of mines (0.8342 <.0001) . Result of evaluation of the effect of some botanicals to control T. absoluta revealed high significant difference between treatment percentage of infested plants number of active mines and yield while significant differencewas observed between treatment in the percentage of the infested fruits.Water extracts of Datura and Neem seed oil were better in reduction of percentage infested plants and number of active mines /polants. All extracts of 3 elites tested plants were better reducing fruit damage percentage and boost tomato yield better than non treated treatment. The obtained results in this study showed the three Sudanese local accessions HSD 6071,HSD11429 and HSD14358 are potent to tolerant infestation of T. absoluta and increase yield of tomato due to their hairiness inclusion of high oercentage of tannin and high count of total soluble solid The three elite accessions can be introduce as sourse of resistance to T. absoluta . . The excellent control of T. absoluta and increment of tomato yield using neem seeds oil and water extracts of Datura and wenca encourage farmes to reduce synthetic insecticides and reduce health hazards and pollution.”Seeds Propagations Program” should be followed to quantify the amount of seeds of the three elites to obtain the gene or genes responsible of resistance and use them for crossing and breeding program