R. Rodriguezkabana et al., ALGINATE FILMS FOR DELIVERY OF ROOT-KNOT NEMATODE INOCULUM AND EVALUATION OF MICROBIAL INTERACTIONS, Plant and soil, 164(1), 1994, pp. 147-154
A method was developed for utilizing alginate films to deliver inoculu
m into soil and evaluate microbial antagonistic activity against nemat
ode eggs. Eggs of Meloidogyne incognita were harvested from galled tom
ato roots (Lycopersicon esculentum), surface disinfested, suspended in
2% (w/v) aqueous sodium alginate, and applied to 2.5 x 5.0 cm polyvin
yl chloride coated fiberglass screens (1.5 mm(2) mesh size) at a unifo
rm thickness of 0.5 mm. The alginate solution was gelled by dipping in
0.25 M CaCl2. Films containing eggs were observed in vitro and egg de
velopment was evaluated. The number of immature eggs and eggs with fir
st stage juveniles declined linearly over time while the number of emp
ty eggs shells, and hatched juveniles increased over time, indicating
that the alginate gel did not inhibit development and motility of M. i
ncognita juveniles. In a greenhouse experiment using cucumber (Cucumis
sativus) the number of galls g(-1) root was correlated with the numbe
r of eggs in alginate films placed in each pot at planting. Films cont
aining M. incognita eggs were buried in field soil containing organic
amendments, incubated, removed from soil, rinsed with water, and obser
ved. The number of immature eggs in grids from soil amended with chiti
n or flax seed meal were lower than in untreated soil; percent parasit
ized eggs was also greater in films from amended soil than from untrea
ted soil.