National Clonal Germplasm Rep - Tree Fruit & Nut Crops & Grapes Site Logo
ARS Home About Us Helptop nav spacerContact Us En Espanoltop nav spacer
Printable VersionPrintable Version     E-mail this pageE-mail this page
Agricultural Research Service United States Department of Agriculture
Search
  Advanced Search
 
Programs and Projects
Subjects of Investigation
 

Research Project: MANAGEMENT OF GENETIC RESOURCES FOR VITIS, PRUNUS, JUGLANS, FICUS, OLEA, PISTACIA, PUNICA, DIOSPYROS, ACTINIDIA, AND MORUS

Location: National Clonal Germplasm Rep - Tree Fruit & Nut Crops & Grapes

Title: Initial screening of chili and sweet pepper germplasm for resistance to chili thrips, Scirtothrips dorsalis Hood.

Authors
item Krishna Kumar, N. - INSTITUTE OF HORT - INDIA
item Aradhya, Mallikarjuna
item Deshpande, A. - INSTITUTE OF HORT - INDIA
item Ramachandar, P. - INSTITUTE OF HORT - INDIA

Submitted to: Euphytica
Publication Type: Popular Publication
Publication Acceptance Date: October 26, 1995
Publication Date: January 25, 1996
Citation: Krishna Kumar, N.K., Aradhya, M.K., Deshpande, A.A., Ramachandar, P.R. 1996. Initial screening of chili and sweet pepper germplasm for resistance to chili thrips, Scirtothrips dorsalis Hood.. Euphytica, 89: 319-324.

Interpretive Summary: A preliminary evaluation for resistance to chili thrips, Scirtothrips dorsalis Hood of 41 and 194 pepper (Capsicum annuum L.) germplasms during 1987 and 1988, espectively, indicated chili accessions may be a promising source of resistance . In contrast, all sweet pepper accessions tested were highly susceptible . A number of chili accessions produced a moderate yield, in spite of a high thrips infestation indicating tolerance to S. dorsalis . Rating for thrips damage was more reliable and efficient than estimating thrips numbers in screening pepper accessions for resistance to thrips. Highly significant, positive correlation between ratings at the seedling stage and final rating for thrips damage indicated the feasibility of screening pepper accessions at the seedling stage . Comparing the similarities in rating among accessions resulted in 40 distinct groups . The variance-covariance matrix of the data from these 40 groups was subjected to principal component analysis . This accounted for 56 and 18 per cent of the variation across the two principal axes, respectively . Projection of chili and sweet pepper accessions along these two axes revealed three distinct clusters . About 80 per cent of chili accessions formed the first cluster, 58 per cent of the sweet pepper accessions formed the second cluster and a third cluster exhibited intermediate ratings for thrips damage. The significance of these findings in relation to geographical divergence and resistance to thrips among pepper accessions is discussed .

Technical Abstract: A preliminary evaluation for resistance to chili thrips, Scirtothrips dorsalis Hood of 41 and 194 pepper (Capsicum annuum L.) germplasms during 1987 and 1988, espectively, indicated chili accessions may be a promising source of resistance . In contrast, all sweet pepper accessions tested were highly susceptible . A number of chili accessions produced a moderate yield, in spite of a high thrips infestation indicating tolerance to S. dorsalis . Rating for thrips damage was more reliable and efficient than estimating thrips numbers in screening pepper accessions for resistance to thrips. Highly significant, positive correlation between ratings at the seedling stage and final rating for thrips damage indicated the feasibility of screening pepper accessions at the seedling stage . Comparing the similarities in rating among accessions resulted in 40 distinct groups . The variance-covariance matrix of the data from these 40 groups was subjected to principal component analysis . This accounted for 56 and 18 per cent of the variation across the two principal axes, respectively . Projection of chili and sweet pepper accessions along these two axes revealed three distinct clusters . About 80 per cent of chili accessions formed the first cluster, 58 per cent of the sweet pepper accessions formed the second cluster and a third cluster exhibited intermediate ratings for thrips damage. The significance of these findings in relation to geographical divergence and resistance to thrips among pepper accessions is discussed .

   

 
Project Team
Preece, John
Aradhya, Mallikarjuna
 
Publications
   Publications
 
Related National Programs
  Plant Genetic Resources, Genomics and Genetic Improvement (301)
 
 
Last Modified: 05/21/2013
ARS Home | USDA.gov | Site Map | Policies and Links 
FOIA | Accessibility Statement | Privacy Policy | Nondiscrimination Statement | Information Quality | USA.gov | White House