Journal of Applied Biology and Biotechnology
Open Access
SCOPUSWeb of Science
  • Year: 2025
  • Volume: 13
  • Issue: 3

Improvement of sweet corn resistance to northern corn leaf blight (NCLB) and downy mildew (DM) through breeding program in Thailand

  • Author:
  • Wassamon Mongkol1,2, Choosak Jompuk1,*, Peeranuch Jompuk3, Kularb Laosatit3, Warapon Bunkoed4, Chaowanart Phruetthithep5, Chalong Kerdsri2
  • Total Page Count: 13
  • Published Online: Dec 25, 2025
  • Page Number: 38 to 50

1Department of Agronomy, Faculty of Agriculture at Kampaeng Saen, Kasetsart University, Nakhon Pathom, Thailand

2Chai Nat Field Crops Research Center, Chai Nat, Thailand

3Department of Applied Radiation and Isotopes, Faculty of Science, Kasetsart University, Bangkok, Thailand

4National Corn and Sorghum Research Center, Kasetsart University, Nakhon Ratchasima, Thailand

5Field and Renewable Energy Crops Research Institute, Bangkok, Thailand

*Corresponding Author: Choosak Jompuk, Department of Agronomy, Faculty of Agriculture at Kampaeng Saen, Kasetsart University, Nakhon Pathom, Thailand, E-mail: agrcsj@ku.ac.th

Online Published on 25 December, 2025.

Abstract

This study aimed to improve the resistance to two major sweet corn diseases in Thailand: northern corn leaf blight (NCLB) and downy mildew (DM). Two sweet corn lines resistant to NCLB (PopHX75C1 and PopCH66C1) were crossed with two waxy corn inbred lines resistant to DM (F4305 and AGWX001) resulting in two hybrid groups: PopHX75C1 × F4305 (group X) and PopCH66C1 × AGWX001 (group C). Self-pollinated progenies from these groups were selected for resistance to both NCLB and DM and further self-pollinated to advanced generations. Disease resistance was evaluated under natural and artificial infection conditions. In the S6 generation, the 14 selected hybrids were assessed for ear yield and agronomic traits. Nine parental lines resisted both NCLB and DM, with the hybrid X3 × C6 demonstrating the highest ear yield of 14.67 tons ha-1. This hybrid also exhibited good eating quality and agronomic characteristics comparable to those of commercial varieties, with a 19% infection rate for NCLB and 7% for DM—lower than those of the commercial hybrids. These results indicate that the selected sweet corn lines with dual resistance to NCLB and DM have the potential as valuable parental lines for future breeding programs. These lines can be used to develop high-yield, disease-resistant hybrids, thereby improving the sustainability and productivity of sweet corn cultivation in Thailand.

Keywords

Sweet Corn, Northern Corn Leaf Blight, Downy Mildew, Line, Hybrid, Disease Resistance