Pilot field trials were conducted against Sesamia cretica Led. using a Granulosis Virus recently isolated from the corn borer infesting maize at Kafr El-Sheikh Governorate. The efficacy of spray application of ScGV was compared with the currently recommended chemical insecticides (Methomyl and Monocrotophos) as two different control strategies against S. cretica larvae on maize. The viral insecticide is a highly purified suspension of granules in water plus 10% molasses as a sticker as well as a feeding stimulant additive. The spray containing 0.1 g of granules/l (i.e. 1.48 x 10" I.B./ml) was applied twice at the rate of 1.25 and 2.5 l/O.Ol feddan (1 feddan = 4200 m' ) at 2 week intervals, starting 3 weeks after sowing. For the chemical insecticides, the methomyl was applied at the same time as the ScGV suspension against S. cretica larvae, and the monocrotophos was applice twice, 2 months after sowing, and 2 weeks later, against Ostrinia nubilalis and Chilo agamemnon larvae. All treatments were made using a portable knapsack sprayer. Additional plots were left as control. Results revealed that both tested treatments (microbial and chemical insecticides) noticeably reduced the numbers of S. cretica larvae. Regarding yield, the mean weight of seeds was higher for the plots which were treated with either virus or insecticide than untreated ones. However, the chemical insecticide treatment was more effective than the formulated virus treatment. The corrected yield in ardab (1 ardab = 145 kg)/feddan were 20.1 1, 16.04 and 12.79, for chemical insecticide, viral insecticide and control treatments, respectively. It is concluded that ScGV seems to be pathogenic to the field population of S. cretica and may be considered a promising biocontrol agent to support the Integrated Pest Management Programme of such an important corn borer.

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Pulp of sour orange fruit; Citrus aurantium v. amara extracted in water and petroleum ether, leaves of lantana; Lantana salvifolia extracted in acetone and leaves of Herb Robert; Geranium robertianum extracted in water at different concentrations 3, 4 and 5% were tested under laboratory conditions against Citrus mealy bug Planococcus citri (Risso) (Pseudococcidae: Homoptera) which is one of the most wide spread insects infesting horticulture crops either inside or outside greenhouses.Data demonstrated that sour orange extracted in petroleum ether the highest reduction in the population of the different stages of the mealy bug being 97.01% after 8 days from treatment with the assayed materials at 5% concentration. While lantana extract in acetone, pulp of sour orange and leaves of Herb Robert extracted in water achieved intermediate reductions in bug population. Also, LT 50 values were determined for the different treatments and it ranged from 2.32 to 3.75 days for leaves of Herb Robert extracted in water and pulp of sour orange extracted in water, respectively.

field experiment was carried out at the Experimental Farm of Sakha Agricultural Station in 2014 rice season using two cultivars, Giza 178 (high tillering capacity) and Egyptian Jasmine (medium tillering capacity) to determine the economic threshold level for control measures of stem borer Chilo agmemnon Bles. in rice. Seven simulated levels of dead hearts; 0, 5, 10, 15, 20, 25 and 30% were adopted to find out their effects on rice yield and yield components. In Giza 178 cultivar, dry matter content was significantly reduced at 25% detillering. Panicle weight, 1000-grain weight and filled grains increased as the detillering level increased. This could be attributed to the compensation phenomenon, as the rice hills that suffered from high detillering produced heavier grains in the remaining tillers. This trend was also obtained with the Egyptian Jasmine. The rice yield was significantly reduced at 15% in the former cultivar and at 20% in the latter one. Economic analysis showed that the economic threshold is 25% damaged tillers in Giza 178 rice cultivar and 20% in the Egyptian Jasmine. This might be due to that Giza 178 is higher tillering cultivar than the Egyptian Jasmine. Thus, control measures, particularly insecticides, should not be applied before dead hearts reach 25% in case of Giza 178 cultivar and 20% in case of Egyptian Jasmine.

This study aimed mainly to estimate the resistance of the cotton leafworm Spodoptera littoralis to several bioinsecticides (Spnitor, Protecto, Dipel DF, Dipel 2X, Agrine and Radical) throughout determining the resistance ratio values. Among all the tested bioinsecticides, Radical had the highest resistance ratio in the four Governorates, while, Spnitor had the lowest resistance ratio in all these Governorates. The relative toxicity of these bioinsecticides to S. littoralis was also determined. The results clearly indicated that Radical was the most toxic bioinsecticides in all four field strains followed by Spnitor, while the other bioinsecticides were the least toxic action.