Abstract. Alharits L, Hemelda NM, Yasman, Handayani W. 2020. Allelopathic activity of Dendrophthoe pentandra as a potential bioherbicide to inhibit seed germination and seedling growth of Eleusine indica. Nusantara Bioscience 12: 33-39. Dendrophthoe pentandra (L.) Miq. is a common parasitic plant in Southeast Asia. As a parasitic plant, it exhibits phytochemicals important for infecting its host, which may be potential as bioherbicide. This study was aimed to evaluate allelopathic activity of D. pentandra (stem and leaf extracts) to control Eleusine indica (L.) Gaertn. seed germination and growth. Methanolic extracts of D. pentandra stem and leaf (0, 1, 2, 3, 4 and 5 mg/mL in water) were treated on E. indica seeds in a petri dish for 10 days. After 10 days, germination of treated E. indica seeds was significantly reduced and reached >80% inhibition at 5 mg/mL. Moreover, E. indica roots were more sensitive compared to E. indica shoots, indicated by root inhibition >50% at 1 mg/mL and reached >90% inhibition at 5 mg/mL. Leaf extract presented stronger inhibition than stem extract, but not significant. It may be related to the higher accumulation of phenolic and flavonoid compounds in leaf extract than in stem extract. This is the first report of allelopathic activity in D. pentandra to inhibit E. indica germination and growth. Therefore, further study in a greenhouse, as well as metabolism effects of D. pentandra on the target weeds are important to provide comprehensive evaluation of D. pentandra potential as bioherbicide.

No abstract

No abstract

Drought stress is one of the most common abiotic stress in agriculture. The use of antitranspirant agents to reduce the effect of drought stress on crops has been considered as a potential method. The application of chitosan as an antitranspirant agent has been reported to be effective in several crops. This study was aimed to analyze the effect of chitosan foliar application for maintaining the growth of lettuce under drought conditions. Three concentrations of chitosan (0.2 g/L; 0.4 g/L; 0.6 g/L) were tested in this study. The parameter observed were the height of the lettuce, number of leaves, leaf length and the width, root length, as well as fresh and dry weight. The drought condition without chitosan application reduced the growth of lettuce in all parameters. Chitosan application at 0.2 g/L was able to reduce the effect of drought stress and maintain the growth of lettuce. However, higher chitosan concentration applications (0.4 g/L and 0.6 g/L) were observed to reduce the growth of lettuce. Based on this study, chitosan was reported to reduce the effect of drought stress in lettuce. As chitosan affects the transpiration process by stomatal closure, a higher concentration of chitosan may also affect the photosynthesis process leading to growth inhibition.

No abstract