Effects of sodium nitroprusside (SNP) pretreatment on UV-B stress tolerance in lettuce (Lactuca sativa L.) seedlings.

Ultraviolet-B (UV-B) radiation is one of the most important abiotic stress factors that could influence plant growth, development, and productivity. Nitric oxide (NO) is an important plant growth regulator involved in a wide variety of physiological processes. In the present study, the possibility of enhancing UV-B stress tolerance of lettuce seedlings by the exogenous application of sodium nitroprusside (SNP) was investigated. UV-B radiation increased the activities of superoxide dismutase (SOD), catalase (CAT), ascorbate peroxidase (APX), peroxidase (POD) and total phenolic concentrations, antioxidant capacity, and expression of phenylalanine ammonia lyase (PAL) gene in seedlings, but the combination of SNP pretreatment and UV-B enhanced antioxidant enzyme activities, total phenolic concentrations, antioxidant capacity, and PAL gene expression even more. Moreover, UV-B radiation significantly inhibited chlorophylls, carotenoid, gibberellic acid (GA), and indole-3-acetic acid (IAA) contents and increased the contents of abscisic acid (ABA), salicylic acid (SA), malondialdehyde (MDA), hydrogen peroxide (H2O2), and superoxide radical (O2•(-)) in lettuce seedlings. When SNP pretreatment was combined with the UV-B radiation, we observed alleviated chlorophylls, carotenoid, GA, and IAA inhibition and decreased content of ABA, SA, MDA, H2O2, and O2•(-) in comparison to non-pretreated stressed seedlings.

Extended longevity of Drosophila melanogaster by water and ethanol extracts of Stachys lavandulifolia.

CONTEXT: Stachyss species have been used as a medicine for centuries throughout the world. Stachys lavandulifolia Vahl. var. lavandulifolia (Lamiaceae) is of interest to researchers because the constituents such as betulinic acid, oleanolic acid, rosmarinic acid, and ursolic acid are similar to other Stachys species commonly used as an alterative in medicinal preparations. OBJECTIVE: The present study investigated the effects of water extract (SLE(w)) and ethanol extract (SLE(e)) obtained from S. lavandulifolia (SLE) on the longevity of Drosophila melanogaster Meigen. MATERIALS AND METHODS: The effects of different concentrations of SLE (Control+DMSO; 4.0; 12.0 and 20.0 µL/100 mL medium) were administered separately to female and male populations of D. melanogaster for control and SLE groups. RESULTS: In all application groups, each population's longevity increased, depending on the concentration of SLE. The mean life-span of the extract groups which are applied with SLE((w)) was determined to be shorter than the extract groups which are applied with SLE((e)). For example, the maximum mean life-span applied with SLE((w)) increased from 31.86 ± 0.92 days to 43.21 ± 1.33 days and the maximum mean life-span applied with SLE((e)) increased from 31.86 ± 0.92 days to 49.62 ± 1.62 days in females. CONCLUSION: These findings demonstrate that the constituents of S. lavandulifolia have great potential as a source for natural health products for D. melanogaster management.

Recovering effects of aqueous extracts of some selected medical plants on the teratogenic effects during the development of D. melanogaster.

In this study the effects of some selected medical plants (Pimpinella anisum L., Rosmarinus officinalis L., Achillea millefolium L., Acorus calamus L., Hypericum perforatum L.) on the development of Drosophila melanogaster have been investigated. When the different concentration of plant extracts were applied to the cultures of Drosophila melanogaster, they did not caused an elongation of metamorphosis of F1 progeny. Furthermore, depending on an increase of plant extract on the application groups, the number of offsprings increased. But this increasing (for application groups no. I, II and IV) was not statistically significant (p > 0.05) according to control group. The highest increase in the total number of offspring of F1 progeny obtained from applications of Acorus calamus extracts and the 10 mL/100 mL medium concentration of the extract of Hypericum perforatum.