Effect of fertilization with municipal sludge on the glutathione, polyamine, and cadmium content of cole crops and associated loopers (Trichoplusia ni)

Abstract

Cabbage and collards grown in pots in municipal sludge amended soil accumulated cadmium. Glutathione content of both young and old leaves was significantly higher in the sludge-grown vegetables than in the corresponding control plants, likely in response to stress factors imposed by the sludge amendment. Putrescine, spermidine, and spermine, measured only in the collards, also increased, possibly by induction due to cadmium accumulation or to general metal stress. Cabbage loopers foraging on the sludge-grown plants assimilated and concentrated cadmium from the contaminated foliage. Putrescine, spermidine, and spermine also increased in the loopers associated,with the collards whereas glutathione did not. The inseds grew larger but developed more slowly on the sludge-grown collards than on the corresponding control plants. Possible accumulation of cadmium in insects by insect-consuming birds is discussed.

Contrasting effects of sewage sludge and commercial fertilizer on egg to adult development of two herbivorous insect species

“…Cabbage loopers did well on the fertilizer-treated broccoli, while the larval stage was prolonged and both the larval and pupal stages had significantly higher mortality on sludge-treated broccoli. Similar results were obtained by Hughes et al (1987), where collards grown in contaminated sludge soil mixtures were larger and greener than collards grown in control soils, and cabbage loopers developed slower on sludge-grown collards. In our study, cabbage loopers developed fastest on broccoli grown in fertilizer-treated soils, indicating that high nutrient content of the fertilized soil was influencing growth as suggested by Hurd and Wolf (1974), Kirchner (1977), Prestidge and McNeill (1982), and Pimentel and Warneke (1989).…”

“…Previous studies (e.g. Hughes et al, 1987;Schmidt et al, 1992), which evaluated the impact of heavy metals on the development of herbivorous insects on plants grown in soils treated with sewage sludge, used artificial soil mixtures or hydroponic solutions, rather than soils from field sites subjected to sludge application and heavy metal contamination. The current study provided a unique opportunity to investigate heavy metal uptake and toxicological effects on egg to adult development of phytophagous insects on plants grown in soils from an old-field ecosystem subjected to 11 years of fertilizer and municipal sludge applications.…”

Significance of Glutathione to Plant Adaptation to the Environment

“…As a consequence of this also the rate of epoxidation (a detoxifying reaction involving GSH) of aldrin was also increased in the parasites. Hughes et al (1987) found also a better performance of Trichoplusia spec. on Brassica grown on sludges.…”

Glutathione Conjugation and Contaminant Transformation

“…Glutathione S-transferase enzymes are present in most organisms, including plants, animals, protozoa, fungi, and bacteria (13). Elevated levels of glutathione and glutathione reductase have been observed in plants exposed to stresses such as heat (60), cold and salinity (61,62), air pollutants including ozone and sulfur dioxide (63-65) and heavy metals (66)(67)(68). Elevated levels of glutathione and glutathione reductase have been observed in plants exposed to stresses such as heat (60), cold and salinity (61,62), air pollutants including ozone and sulfur dioxide (63-65) and heavy metals (66)(67)(68).…”

“…Increases in glutathione, glutathione reductase, and glutathione S -transferase levels have been linked to organism resistance and adaptation to a variety of physical and chemical stresses encountered in the environment ( , ). Elevated levels of glutathione and glutathione reductase have been observed in plants exposed to stresses such as heat (), cold and salinity ( , ), air pollutants including ozone and sulfur dioxide ( − ) and heavy metals ( − ).…”