Field Screening of Maize (Zea mays L.) Genotypes against Turcicum Leaf Blight (TLB) under Artificial Conditions
D. Keerthana *
Agricultural College-Bapatla, Acharya N.G Ranga Agricultural University, Guntur 522101, India.
T. Haritha
Department of Genetics and Plant Breeding, Agricultural College Farm, Bapatla, Guntur 522101, India.
I. Sudhir Kumar
Department of Genetics and Plant Breeding, Agricultural Research Station (ARS), Peddapuram, East Godavari 533437, India.
D. Ramesh
Department of Statistics and Computer Application, Agricultural College-Bapatla, Acharya N.G Ranga Agricultural University, Guntur 522101, India.
*Author to whom correspondence should be addressed.
Abstract
Background: There are a variety of critical problems facing tropical maize cultivation, such as disease infestation, insect/pest and weed problems. Foliar diseases in particular cause significant losses in agricultural yield. Leaf blight, known as northern leaf blight, is a disease of maize leaves caused by an overgrowth fungus. Therefore, it was necessary to develop sources of resistance to TLB and then a field experiment was conducted to study the performance of 64 genotypes (44 test crosses, 11 lines, 4 testers and 5 checks) During Spring 2021-22 at the Agricultural College Farm, Bapatla.
Methods: Screening was carried under field conditions by adopting an artificial disease inoculation technique Disease score was recorded at tasseling, 20 DAT and maturity stages by using 1-9 scale.
Results and Discussion: At maturity stage 12 crosses, seven lines and one check showed resistant reaction (R); 25 crosses, 4 inbreds, one check showed moderately resistant reaction (MR); 7 crosses, 3 inbreds and one check showed moderately susceptible reaction (MS) and one inbred, two checks showed susceptible reaction (S) under field screening.
Conclusion: The lines VL171488-2, VL18828, VL19705-8, VL18142, VL175869, SNL19582-22 and tester LM13 showed resistant disease reaction for TLB pathogen at phenotypic level. These lines can be used in future TLB resistance breeding programmes.
Keywords: Genotypes, Zea mays, Turcicum leaf blight, resistance breeding programmes