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RESEARCH EVALUATION OF ENVIRONMENTAL

FRIENDLY PRODUCTS FOR CONTROL

OF NEMATODES ON COTTON

Although few nematicides are available for he root-knot nematode (RKN),
the control of Meloidogyne spp. nematodes Tespecially Meloidogyne javanica,
on cotton, Oxamyl still performed best is by far the most important nematode

compared to other environmental friendly pest of cotton worldwide. Root-knot
nematodes, in particular Meloidogyne
products currently available. incognita race 4, are the predominant
nematode species that adversely
EXPERIMENTAL DESIGN affects the production of cotton in
A glasshouse experiment was treatments, replicated 6 times in South Africa and thus result in
conducted at the ARC-Industrial Crops separate 3kg pots with three plants substantial yield losses. Other
Institute in Rustenburg and the following each. Candia B2RF cotton cultivar was nematodes, such as Pratylenchus spp.
treatments were evaluated: used for study. Two plants were used for and Trichodorus spp. are widely found
nematode assessments during season
i. Untreated control, and one used for harvest end of season. but not of economic importance in
ii. Standard Nematicide (Oxamyl) 10l/ha Nematodes were extracted according to cotton. Meloidogyne spp. are
at planting. the procedure of Jenkins (1964) from widespread and attack a wide range of
iii. Seed Treatment (Clothianidin) one 250-ml sub-sample taken from the hosts, both cultivated and
prepared by Bayer personnel. composite sample from each plot for uncultivated. Following the 2005
iv. OR_079 (10% Pressed orange oil) + identification and quantification of all
international withdrawal of methyl
Standard nematicide (Oxamyl) 7 plant parasitic nematodes (PPN)
days before planting and standard present. Then nematode samples (for bromide (MB) in management of plant-
nematicide at planting. soil and roots) counting were done parasitic nematodes due to its eco-
v. OR_079 100g/l applied 7 days before before planting (soil only), 6 weeks after unfriendliness, Meloidogyne spp.
planting and at planting. planting and 12 weeks after planting. To increasingly became the most
vi. OR_079 100g/l applied 7 days before determine nematode root infestation, debilitating nematode genus, which
planting and at planting + OR_151 one randomly selected plant from the
(plant derived flavonoids in an organic each pot was sampled at 6 and 12 left producers with limited options.
carbon complex) 250ml/ha of applied weeks after planting. There are no commercial cotton
at 14days after planting and 28 days RESULTS varieties resistant to root-knot
later. nematodes available in South Africa. It
95% of the seedlings develop sufficient
is therefore imperative to evaluate the
Mixed growth medium and sandy soil root/stem systems that ensured
were sterilised to remove any pathogens. adequate number of test plants per pot. effectiveness of nematicides and
The soil was transferred to pots in Moreover, sampling was destructive by biological agents for the management
glasshouse. Tomatoes roots infested with uprooting the whole plant system to of nematodes in a cotton farming
the root knot nematodes Meloidogyne allow root and soil around root system to system.
incognita and Meloidogyne javanica were be assayed. The initial population of
incorporated to the soil to establish nematodes in soil showed no significant significant difference among treatments.
nematode population. Soil samples were difference in each pot for each Untreated control had significantly higher
taken for analysis of nutrients. Planting treatment. Although the untreated number of nematodes in soil compared to
date was 13 February 2017. During the control had higher number of standard nematicide and seed treatment.
trial, 20g/l cypermethrin was sprayed to nematodes counted in the soil In addition, standard nematode and seed
control aphids. compared to other treatments, there treatment had no significant difference with
was no significant difference in the other treatments except for untreated
The experiment comprised of a number. At week six, M. javanica control. At week 12, nematode counts in
randomized block design with six populations in the soil showed continued on next page
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