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Egyptian Journal of Agronomy http://agro.journals.ekb.eg/ Review 20T HE WATER stress harshly influences the plant growth and development with considerable reductions in plant growth and biomass accumulates. It declines the number of bolls per plant, bolls weight, and seed cotton (Gossypium spp.) yield. Fiber length, fiber strength, seed index and boll weight are reduced dynamically. The relative leaf water contents, transpiration rate and leaf water potential are decreased while leaf and canopy temperature is increased under water stress conditions. Limited water availability restricts the total uptake of nutrients, thus deprecating their concentration in the plant tissues. The major effects of water stress on the plants are lowered photosynthesis stimulated by reduced leaf expansion, early leaf senescence, deteriorated photosynthetic machinery and reduction in food production.The Plant accomplishes escape from moisture stress by shortening its growing season which results in a reduction in yield. The plants cut down their water spending under water stress conditions by dercreasing the number and area of leaves to minimize the yield losses. The growth and development of tolerant genotypes are relatively fast because of retention of more moisture from soil earlier. Genes are induced by water stress, categorized into regulatory and functional genes; from them, functional genes produce functional proteins, whereas regulatory genes product regulatory proteins like transcriptional factors, they control a cluster of genes by regulating the expression of different targeted genes in their promoter region through specific binding of it with cis-acting elements. The development of stress-tolerant cotton varieties based on the stability of yield and yield components under water stress conditions should be the prime focus of breeders.

B rassica spp. family Cruciferae has a prime position as a resource of edible oil for humans (Mandal et al., 2012). In Pakistan, the most abundant species of Brasicae comprise Brassica campestris L., B. juncea L. and B. napus L. (Khan and Begum, 2005). It occupies an area of 2,22,000 hectares with 4,88,000 tons of production (Anonymous, 2021).

The present study was designed to determine the LC50 of some insecticides commonly used against Helicoverpa armigera and their comparative efficacy against the insect pest. The second instar larvae of H. armigera reared in the laboratory were selected for leaf dip bioassay. Two types of insecticides viz. conventional (deltamethrin and bifenthrin) and new chemistry (spinosad and indoxacarb) were assessed in the present studies. The results revealed that bifenthrin was more toxic to the second instar larvae of H. armigera at all the doses with lower LC50 value of 120.007 ppm as compared to deltamethrin with the highest LC50 value of 292.404 ppm. Among the new chemistry insecticides, indoxacarb proved to be more toxic than spinosad with LC50 of 5.592 ppm. LC50 of spinosad was 8.201 ppm showing 1.46 times less toxicity than indoxacarb.