Comparative study of 2 protection strategies against Tuta absoluta (Meyrick) in late open field tomato crops in Tunisia

A comparative study of 2 protection strategies against Tuta absoluta (Meyrick) in open field tomato crops was performed. The first strategy used Integrated Pest Management (IPM) through mass trapping, release of Nesidiocoris tenuis and rational use of compatible insecticides. The second strategy was based on conventional use of synthetic insecticides (9 treatments). This study revealed at the end of the culture a 20% infestation rate of leaves in the IPM cropping system versus 98% in the conventional cropping system. The infestation rate of fruit was 18.2% in the IPM cropping system versus 46.8% with the conventional one.     

Physico-chemical characteristics of a seed fiber arised from <Emphasis Type="Italic">Pergularia Tomentosa</Emphasis> L.

In the present paper, we analyze a seed fiber arising from Pergularia tomentosa L. (PTL). It was, primarily, characterized using different techniques. The morphology of the fibers was observed via Scanning Electron Microscopy (SEM). They are also checked in term of decomposition behavior through TGA/DTG instrument. The cristallinity index was determined using XRD and it was about 52 %. The chemical composition in terms of moisture percent, ash, waxes and fats, lignin, hemicellulose and cellulose were, respectively 8.5 %, 2.74 %, 1.88 %, 8.6 %, 16 % and 43.8 %. The contact angle value was measured and the evolution of drop profile was captured with video-camera using GBX Tensiometer Surfaces Sciences Studies. Further, fibers were dyed with Methylene Blue, Direct Red 79, Sumifix supra yellow 3RF and Reactive Blue 198. Color coordinates (ΔL*, Δa*, Δb*, ΔC* and ΔH*) of the samples were so measured. All obtained data were compared to cotton fibers and some other cellulosic fibers. The Results revealed that, based on such properties, PTLF could be a competitive fiber in many applications field (textile weaving, composites, etc).