Delayed maturity in soybean, Glycine max (L.) Merr., occurred in response to infestation by southern green stink bug, Nezara viridula (L.), in 4 yr of field studies. Maturity delays followed stink bug infestation that occurred only during the pod set and filling stages (R3-R5.5), and infestations at R3-4 and R5 resulted in delayed maturity more consistently than did infestation at R5.5. Infestation levels of six stink bugs per 0.3 m of row for 7-14 d generally were required to delay soybean maturity. The greatest impact on seed yield and quality parameters followed stink bug infestations that occurred during R3-R5.5, which corresponded closely with the periods of infestation that resulted in delayed maturity. If both delayed maturity and yield reduction are considered, the pod elongation through late pod filling stages were most critical for protecting soybeans from southern green stink bugs.

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Mortality of eggs, first, third, and fifth instars and adults of fall army worm (FAW), Spodoptera frugiperda (J. E. Smith), after exposure to several insecticides on cotton indicated that the FAW is susceptible to most insecticides currently used to control Heliothis spp. Most insecticides tested exhibited ovicidal activity. High mortality of first instar larvae was observed for most treatments, including the biological insecticide, Bacillus thuringiensis (Berliner). More variation in mortality among treatments was observed in third and fifth instars than in first instars. Pyrethroid, carbamate, and organophosphorous insecticides resulted in higher mortality than did B. thuringiensis. Diflubenzuron, an insect growth regulator, was as effective as commonly used insecticides against third and fifth instar larvae when mortality was observed at pupation. Third instar FAW placed on plant tissue from the upper section of cotton plants sprayed in field situations suffered higher mortality than those placed on plant tissue from lower sections in the plant canopy. Inadequate deposition of insecticide in the lower portions of the cotton plant appears to be a limiting factor in control of FAW larvae on cotton.