Use Of Cymbopogon Citratus Leaf Essential Oil For Management Of Anthracnosis In Yam-Grops

The essential oil of Cymbopogon citratus (DC.) Stapf. (Lemongrass) has been positioned as a phytosanitary alternative to counteract the effects caused by phytopathogenic fungi. The aim of the present study was to evaluate in vitro the inhibitory activity of essential oils from Cymbopogon citratus (lemongrass) leaves against Colletotrichum gloeosporioides. Leaves of the silver species Cymbopogon citratus were collected in the sub-region of the savannahs of the department of Sucre; for the extraction of essential oils (EO), fresh leaves were weighed and EO was obtained using the microwave-assisted hydrodistillation method. The antifungal activity of the EOs was evaluated using the surface seeding technique on solid medium, the activity was expressed as percentage inhibition index. Chemical characterisation of the essential oils was performed by gas chromatography coupled to mass spectrometry. The highest antifungal index efficiency of lemongrass was observed at concentrations of 5,000, 8,000 and 10,000 ppm. The main constituent identified in lemongrass EOs was citral, which is possibly related to the inhibitory activity of the fungus causing anthracnose disease in yam crop

Evaluation of the potential of Chlorella vulgaris for the removal of pollutants from standing water

In this study we evaluated the microalga Chlorella vulgaris in order to determine the ability of the microalga to remove the highest concentration of contaminants present in stagnant water. A mixing design of the microalgae with the wastewater was carried out for 20 days, with a 12:12 h photoperiod, in a greenhouse. The highest removal efficiencies for heavy metals were ≥ 98% (mainly Cd, Hg, As and Pb) and ≥ 90% for BOD5, COD, nitrates, phosphates, total phosphorus, faecal and total coliforms. Finally, according to the design analysis, it was determined that the optimal microalgae mixture 1:10 achieves the highest DO production and the highest removal, in a cultivation time of 15 days. In conclusion, microalgae demonstrate their capacity for bioremediation of rural domestic wastewater jagüeyes

STUDY OF THE ANTIBACTERIAL ACTIVITY OF PLANT-DERIVED MEATABOLITES AGAINST PHYTOBACTERIA IN RICE CULTURE

Bacterial blast of the rice panicle, caused by the Gram-negative bacterium Burkholderia glumae, causes grain rot, generating losses of 15 to 80% of production. Although integrated management methodologies and the use of agrochemicals have been implemented to mitigate this situation, satisfactory results have not been achieved, and the excessive use of oxolinic acid has generated resistance on the part of the bacterial strains and, on the other hand, the safety of the final product for food safety worldwide. The present study aimed to implement new environmentally friendly biocontrol strategies such as the use of essential oils of Lippia alba and Lippia origanoides to reduce losses in rice crops caused by B. glumae, finding significant results of the essential oils, observing antibacterial activity of 100%, Lippia origanoides at a concentration of 90 ppm.   Lippia alba had inhibitory activity at 1550 ppm with 80% effectiveness. The chemical profiles of the essential oils showed thymol as the major secondary metabolite with an area percentage of 68% for the essential oil of L. origanoides, while L. alba contains geranial and neral in 35% and 29% respectively and are possibly associated with antibacterial activity against B. glumae and its future use for the biological management of bacterial blast in rice plants