In-vitro evaluation of exotic Hevea genotypes for resistance to Corynespora cassiicola.

Achuo E. A., . and Ebai M. M., . and Gobina S. M., . In-vitro evaluation of exotic Hevea genotypes for resistance to Corynespora cassiicola. pp. 255-269. ISSN 1511-1768

Hevea leaf fall disease caused by Corynespora cassiicola (Berk Curt) Wei is one of the major disease constraints to the production of natural rubber (Hevea brasiliensis) in South Cameroon. Attempts to control this disease by traditionally recommended practices such as artificial defoliation or aerial spray of fungicides have not yielded satisfactory results in Cameroon. Production of disease resistant planting material may provide a more efficient disease control strategy. As part of a screening process of a large pool of Hevea genetic resources for disease resistance we evaluated in-vitro. 28 genotypes collected from Amazonia. These genotypes were tested for resistance to two isolates of C. cassiicola (NK01 and NK02) obtained from different clones showing different levels of susceptibility to the disease in the same field in South Cameroon. The two isolates had similar growth characteristics on culture media. However isolate NK01 grew faster than NK02 on Potato Dextrose Agar and was also more virulent on the lest material. The two isolates may belong to different races. To verify this further characterisation of the isolates is recommended. Significant differences were observed in the response of the tested Hevea genotypes to each of the isolates. Genotypes AC/S/12/22 RO/07/48. and AC/B/19/22 had the highest resistance to both isolates. These could constitute good source material in breeding for disease resistance. Due to their high susceptibility to both isolates genotypes AC/S/12/02 MT/I/25 MT/C/04/22 MT/C/04/27 and RO/C/08/33 may have to be avoided in any such breeding programme.

Full text available from: Official URL: http://vitaldoc.lgm.gov.my:8060/vital/access/servi...

Abstract

Hevea leaf fall disease caused by Corynespora cassiicola (Berk Curt) Wei is one of the major disease constraints to the production of natural rubber (Hevea brasiliensis) in South Cameroon. Attempts to control this disease by traditionally recommended practices such as artificial defoliation or aerial spray of fungicides have not yielded satisfactory results in Cameroon. Production of disease resistant planting material may provide a more efficient disease control strategy. As part of a screening process of a large pool of Hevea genetic resources for disease resistance we evaluated in-vitro. 28 genotypes collected from Amazonia. These genotypes were tested for resistance to two isolates of C. cassiicola (NK01 and NK02) obtained from different clones showing different levels of susceptibility to the disease in the same field in South Cameroon. The two isolates had similar growth characteristics on culture media. However isolate NK01 grew faster than NK02 on Potato Dextrose Agar and was also more virulent on the lest material. The two isolates may belong to different races. To verify this further characterisation of the isolates is recommended. Significant differences were observed in the response of the tested Hevea genotypes to each of the isolates. Genotypes AC/S/12/22 RO/07/48. and AC/B/19/22 had the highest resistance to both isolates. These could constitute good source material in breeding for disease resistance. Due to their high susceptibility to both isolates genotypes AC/S/12/02 MT/I/25 MT/C/04/22 MT/C/04/27 and RO/C/08/33 may have to be avoided in any such breeding programme.

[error in script]

Item Type:	Article
AGROVOC Term:	Corynespora cassiicola
AGROVOC Term:	Hevea brasiliensis
AGROVOC Term:	Genotypes
AGROVOC Term:	Natural rubber
AGROVOC Term:	In vitro
AGROVOC Term:	Exotic breeds
AGROVOC Term:	Leaf diseases
AGROVOC Term:	Leaf fall
AGROVOC Term:	Plant diseases
AGROVOC Term:	Planting
Depositing User:	Ms. Suzila Mohamad Kasim
Last Modified:	24 Apr 2025 06:28
URI:	http://webagris.upm.edu.my/id/eprint/23203

Actions (login required)

View Item