Study of Powdery Mildew Resistance in seven Lines of Snow Pea, Pisumsativum

C Sittigul ,N Potapohn ,Angsana Akkarapisan,Anchan Chompupoung,Weenun Bundithya,Siripong Kumphai

doi:10.5539/jas.v4n5p209

Abstract

Snow pea is one of the important crops grown on highland of Thailand. However, it is very susceptible to powdery mildew. Thus, resistant cultivar increases the production of this crop at a reduced costs. Seven pea lines/cultivars, namely P117, P185, P309, No.3, No.4, No.5 and Fang No.7, were evaluated for phenotypic powdery mildew resistance at Pang Da Royal Agricultural Station, Samoeng district, Chiang Mai during the period of November, 2007 – March, 2008. They were divided into 3 groups: highly resistant group (R) i.e. P117, P185 and P309, moderately resistant group (M) i.e. No.3, No.4 and 5, and susceptible group (S) i.e. Fang No.7. In addition, DNA marker for powdery mildew resistance, er , was tested using PCR technique with 3 primers, ScOPD10, OPU17 and OPO02. It was found that only ScOPD10 could yield an 850-bp marker specific to resistant group. DNA sequencing of this 850 bp marker showed 618-624 bases. The sequence was compared with databases in NCBI GenBank. After BLAST searches, the 618-624 base sequences had 90-91% homology to the DNA sequence from clone JICPSV-598E15, complete sequence of P. sativum .

Highlights

Snow pea, Pisumsativum L.(Fabaceae), is an important source of protein which has continuously increased market demand and becomes popular for the Thai consumers
The results showed that in all stages of growth of cultivar Fang No.7, the highest severity on infection (100%) was observed on the leaves
Base on the disease severity ratings of the study, the tested materials were classified into 3 groups as follows; highly resistant (R), lines P117, P185 and P309; moderately resistant (M), lines No.3, No.4 and No.5 and susceptible (S), cultivar Fang No

Summary

Introduction

Pisumsativum L.(Fabaceae), is an important source of protein which has continuously increased market demand and becomes popular for the Thai consumers. The commercial snow pea cultivars, widely used by farmers, produce high yield but are very susceptible to powdery mildew disease. There is a report that the resistance to the powdery mildew disease in pea is controlled by recessive gene er-1 and (or) er-2. DNA maker is a tool that has been widely used to identify and separate resistant pea cultivar from the susceptible cultivar by using polymorphic band of er gene linkage such as ScOPO181200 and ScOPE161600 in Canadian resistant cultivar (Tiwari et al.,1998), OPU171000 and ScOPD10650 in Indian resistant cultivar whereas OPO021400 in Indian susceptible cultivars (Janila and Sharma, 2004). The objective of this study was to identify the er gene-linked molecular marker in snow peas which were developed in Thailand by using three primers, OPU17, OPO02 and ScOPD10 which were reported by Janila and Sharma (2004)

Objectives

Methods

Results