Cool-Season Weed Control Using Ammonium Nonanoate and Cultivation in Organic Vidalia® Sweet Onion Production

Ammonium nonanoate is registered for weed control in certified organic cropping systems and may be useful to control cool-season weeds in organic Vidalia® sweet onion production. Ammonium nonanoate combined with tine-weeder cultivation was evaluated for weed control in organic onion in Georgia. There were no statistical interactions between main effects of herbicides and cultivation with a tine weeder for cool-season weed control and onion yield, indicating that ammonium nonanoate does not improve weed control compared with cultivation. Ammonium nonanoate at 4% and 6% did not adequately control weeds and onion yields were reduced. Ammonium nonanoate at 8% and 10% controlled cutleaf evening-primrose and lesser swinecress equal to the standard of d-limonene (14%), but the degree of control did not consistently protect onion yields from losses due to weeds. These results are in agreement with previous studies using clove oil and pelargonic acid. There is no advantage to using ammonium nonanoate for cool-season weed control in organic Vidalia® sweet onion production.

Family instability and children's effortful control in the context of poverty: Sometimes a bird in the hand is worth two in the bush

Effortful control has been demonstrated to have important ramifications for children's self-regulation and social–emotional adjustment. However, there are wide socioeconomic disparities in children's effortful control, with impoverished children displaying heightened difficulties. The current study was designed to demonstrate how instability within the proximal rearing context of young children may serve as a key operant on the development of children's effortful control in the context of poverty. Two separate studies were conducted that included samples of children living within homes characterized by heightened economic risk. In Study 1, we tested the differential prediction of family instability on two domains of children's effortful control: cool effortful control and delay control. Consistent with hypotheses, elevated instability was associated with decreased hot effortful control but not cool effortful control over the span of 2 years. In Study 2, we examined how children's basal cortisol activity may account for associations between heightened instability and effortful control in reward tasks. The results were consistent with sensitization models, suggesting that elevated cortisol activity arising from increased uncertainty and unpredictability in rearing contexts may influence children's hot effortful control. The findings are interpreted within emerging evolutionary–developmental frameworks of child development.

X-Y chromosome dissociation in mice and rats exposed to increased testicular or environmental temperatures

Heating the testes, scrota and tails of mice and rats by immersion in a water bath at 42 degrees C for 20 min caused an increased percentage of X-Y univalents in meiotic preparations made after 6 and 12 days respectively. It was also confirmed that exposing mice of a cool-adapted strain to an environment at 33 degrees C for 5 days resulted in an increase in the percentage of X-Y and autosomal univalents in meiotic preparations made after a recovery period of 2 days. Mice of a strain adapted to living at 33 degrees C also showed a higher rate of X-Y dissociation than control cool-adapted mice, but a lower frequency of autosomal univalents than cool-adapted mice exposed to the hot environment. The testes of the heat-adapted mice were even more sensitive than the testes of cool-adapted mice to the effects of local heating, as judged by the fall in testis weight 21 days afterwards.