From: "Lawrence F. London, Jr." <venaurafarm@bellsouth.net>
To: permaculture <permaculture@lists.ibiblio.org>
Subject: [permaculture] Vetiver as a control for stem borer: Re: [SANET-MG] News from the other side
Date: Wed, 20 Oct 2010 21:56:56 -0400
-------- Original Message --------
Subject: Re: [SANET-MG] News from the other side
Date: Tue, 19 Oct 2010 11:13:37 +1100
From: Don Miller <donmillernz@GMAIL.COM>
To: SANET-MG@LISTS.IFAS.UFL.EDU
Buffer plantings of Vetiver grass (*Chrysopogon zizanioides*) might also
be an option for farmers in Hawaii and other tropical areas. In this
case it is a host that reduces populations. The erosion control
function of the sterile, non-invasive vetiver is an added advantage.
*Stem borers attack maize, sorghum, rice and millets in Africa and Asia.
The moths lay their eggs on the leaves of the crop. Professor Johnnie
van den Berg, entomologist, (School of Environmental Sciences and
Development, Potchefstroom University, South Africa.) found that the
moths prefer to lay eggs on the leaves of vetiver planted around the
crop instead of on the maize or rice crop itself. Given the option,
about 90% of the eggs are deposited on vetiver instead of on the crop. *
*Because vetiver leaves are hairy, the larvae that hatch on them cannot
move around easily. The larvae fall off the plant and die on the ground,
resulting in very high mortality, about 90%. Vetiver also harbours many
helpful insects that are predators of pests that attack crops. In
cooperation with Dr. van den Berg, Can Tho University is currently
studying the practical application of this effect on rice. Preliminary
results are very promising. Van den Berg also reports that the sugar
cane borer, Eldana saccharina (in some countries such as India Chilo
partellus prefers to lay its eggs on vetiver. In India Chilo partellus
also is found in cane. Vetiver grass hedgerows provide very good habitat
for beneficail insects such Chrysopidae sp. and other beneficail
insects. Vetiver alone is not enough to
control pests and must be part of an overall IPM package that manages
crop health.*