Limits...
Genetic variability of the bollworm, Helicoverpa armigera, occurring on different host plants.

Subramanian S, Mohankumar S - J. Insect Sci. (2006)

Bottom Line: This preliminary study uses 10 microsatellite simple sequence repeat (SSR) markers, to provide insight into the genetic variability of H. armigera populations from six different host plants.Nine of the SSR primers indicated high variability across the different host associated populations with polymorphism ranging from 75 to 100 per cent.Using the un-weighted pair-group method analysis, H. armigera collected and reared from cotton stood out as unique in one cluster while the insects collected and reared on all other hosts grouped separately.

View Article: PubMed Central - PubMed

Affiliation: Department of Plant Molecular Biology and Biotechnology, Tamil Nadu Agricultural University, Coimbatore, India. subbisgv@rediffmail.com

ABSTRACT
The bollworm, Helicoverpa armigera Hübner (Lepidoptera: Noctuidae) is a polyphagous pest of worldwide occurrence inflicting annual crop damage in India worth US$ 1 billion. In India this insect occurs as a major pest in many economically important crops, including cotton, pigeonpea, chickpea, tomato, okra, and blackgram. Understanding the genetic variation among the H. armigera populations occurring on host plants has become essential to understand the variation in their susceptibility to different insecticides, including Bacillus thuringiensis . This preliminary study uses 10 microsatellite simple sequence repeat (SSR) markers, to provide insight into the genetic variability of H. armigera populations from six different host plants. Nine of the SSR primers indicated high variability across the different host associated populations with polymorphism ranging from 75 to 100 per cent. Using the un-weighted pair-group method analysis, H. armigera collected and reared from cotton stood out as unique in one cluster while the insects collected and reared on all other hosts grouped separately.

Show MeSH

Related in: MedlinePlus

Simple sequence repeat (SSR) fragments generated from Helicoverpa armigera obtained from different host plants
© Copyright Policy - open-access
Related In: Results  -  Collection

License
getmorefigures.php?uid=PMC2990316&req=5

i1536-2442-6-26-1-f02: Simple sequence repeat (SSR) fragments generated from Helicoverpa armigera obtained from different host plants

Mentions: The genetic variability of six populations of H. armigera collected from different host species (Fig. 1) was investigated by PCR analysis of DNA from one adult female randomly selected from each of these populations using 10 SSR primers. All ten primers listed produced scorable markers in each DNA sample and the primer HaSSR2 was found to produce a single monomorphic band for all DNA samples. Sample gels resulting from the HaSSR1, 2, 3, 4 and 10 primers across the populations collected from different hosts are presented in Figure 2. A total of 61 markers from 10 primers were available for analysis across the different populations. The highest numbers of 16 markers were produced by the primer HaSSR 1, followed by 8 markers by HaSSR 8 with high degree of polymorphism 75–100%. The primer HaSSR 1 was found to be highly informative to differentiate the host associated populations with a polymorphism information content value of 0.92 (Table1). The calculation of the dice coefficient values were based on the presence or absence of SSR bands. The coefficient values ranged from 0.348–0.741 (Table 2). The H. armigera populations occurring on tomato and bhendi were found to be closely related with a coefficient of 0.741, while the population occurring on cotton and blackgram was found to differ widely with a coefficient value of 0.348. The population on cotton was found to be distantly related to the others with lower dice coefficients.


Genetic variability of the bollworm, Helicoverpa armigera, occurring on different host plants.

Subramanian S, Mohankumar S - J. Insect Sci. (2006)

Simple sequence repeat (SSR) fragments generated from Helicoverpa armigera obtained from different host plants
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC2990316&req=5

i1536-2442-6-26-1-f02: Simple sequence repeat (SSR) fragments generated from Helicoverpa armigera obtained from different host plants
Mentions: The genetic variability of six populations of H. armigera collected from different host species (Fig. 1) was investigated by PCR analysis of DNA from one adult female randomly selected from each of these populations using 10 SSR primers. All ten primers listed produced scorable markers in each DNA sample and the primer HaSSR2 was found to produce a single monomorphic band for all DNA samples. Sample gels resulting from the HaSSR1, 2, 3, 4 and 10 primers across the populations collected from different hosts are presented in Figure 2. A total of 61 markers from 10 primers were available for analysis across the different populations. The highest numbers of 16 markers were produced by the primer HaSSR 1, followed by 8 markers by HaSSR 8 with high degree of polymorphism 75–100%. The primer HaSSR 1 was found to be highly informative to differentiate the host associated populations with a polymorphism information content value of 0.92 (Table1). The calculation of the dice coefficient values were based on the presence or absence of SSR bands. The coefficient values ranged from 0.348–0.741 (Table 2). The H. armigera populations occurring on tomato and bhendi were found to be closely related with a coefficient of 0.741, while the population occurring on cotton and blackgram was found to differ widely with a coefficient value of 0.348. The population on cotton was found to be distantly related to the others with lower dice coefficients.

Bottom Line: This preliminary study uses 10 microsatellite simple sequence repeat (SSR) markers, to provide insight into the genetic variability of H. armigera populations from six different host plants.Nine of the SSR primers indicated high variability across the different host associated populations with polymorphism ranging from 75 to 100 per cent.Using the un-weighted pair-group method analysis, H. armigera collected and reared from cotton stood out as unique in one cluster while the insects collected and reared on all other hosts grouped separately.

View Article: PubMed Central - PubMed

Affiliation: Department of Plant Molecular Biology and Biotechnology, Tamil Nadu Agricultural University, Coimbatore, India. subbisgv@rediffmail.com

ABSTRACT
The bollworm, Helicoverpa armigera Hübner (Lepidoptera: Noctuidae) is a polyphagous pest of worldwide occurrence inflicting annual crop damage in India worth US$ 1 billion. In India this insect occurs as a major pest in many economically important crops, including cotton, pigeonpea, chickpea, tomato, okra, and blackgram. Understanding the genetic variation among the H. armigera populations occurring on host plants has become essential to understand the variation in their susceptibility to different insecticides, including Bacillus thuringiensis . This preliminary study uses 10 microsatellite simple sequence repeat (SSR) markers, to provide insight into the genetic variability of H. armigera populations from six different host plants. Nine of the SSR primers indicated high variability across the different host associated populations with polymorphism ranging from 75 to 100 per cent. Using the un-weighted pair-group method analysis, H. armigera collected and reared from cotton stood out as unique in one cluster while the insects collected and reared on all other hosts grouped separately.

Show MeSH
Related in: MedlinePlus