The effects of incorporating a hydrogel polymer with sand on development of selected maize (Zea mays, L.) grown under saline conditions has been demonstrated. The seeds of maize was germinated in sand/swollen hydrogel polymer mixture (80:20 v/v) with added Hoagland nutrient solution, then transplanted after 7 days from germination into a range of sand/swollen hydrogel polymer (90:10 v/v) in plastic growbags. Saline solutions containing NaCl, CaCl 2 , mgCl 2 (0.0, 2,000, 4,000, 6,000, 8,000 ppm.)were applied to the growbags (to field capacity twice per week, alternating with a comparable watering regime. Polymer incorporating with sand reduced the effect of salinity treatments. Maize (Zea mays, L.) adapted to salinity (< 8,000 ppm) was found to have undergone extensive osmotic adjustment by accumulation of organic and inorganic solutes. With the exception of 2,000 ppm, salinity decreased seed germination, plant growth yield production and mitotic division. With salinity treatment the water content tended to increase more in the root with salinity treatment, but succulence was greater in shoot than root. Total pigments (chlorophyll a + b & carotenoids) and photosynthetic activity decreased with salinity treatments. The results indicate that adaptation of maize plant to salinity stress had occurred; may make significant contributions by using hydrogel polymer to improve the soil characters and adapted the maize plant to salinizations.

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Insecticide residues were detected in 10 of the 15 insect species examined. The most common insecticide residues were , 'and its metabolite , '-.. The concentrations ranged from 0.10 to 9.16 p.p.m. and from a trace to 12.89 p.p.m., respectively. Aldrin, dieldrin, endrin, heptachlor epoxide, chlordane, and toxaphene also were present in some samples. Laboratory studies on the persistence of DDT in Heliothis spp. showed the fast disappearance of DDT, followed by the disappearance of DDE. There was no change in the level of , 'in diapausing bollworm pupae over a period of 5 months. All of the eight bird species examined showed residues of , 'and/or , '-with concentrations ranging from 0 to 132.50 p.p.m. and from a trace to 37.50 p.p.m., respectively. In most cases, the fat tissue contained higher levels of residues than the other tissues. Chlorinated hydrocarbon insecticides have been used extensively during the past 20 years in controlling various insect pests. As a result, contamination of the environment by these residual insecticides is almost universal (George, 1963).Cotton fields represent an ecological area where large amounts of chlorinated hydrocarbon pesticides are used annually. Exactly how much of these chemicals are present in beneficial (predaceous) and pest (phytophagous) insects of cotton, nearby aquatic insects, and birds feeding in cotton fields on insects, nectar, and seeds is unknown. In order to establish the magnitude of contamination and to obtain basic information on the residue problem, a survey of the chlorinated hydrocarbon insecticide residues in selected insects and birds found in association with cotton fields in Louisiana was undertaken.