Screening and characterization of exotic germplasms of bread wheat against leaf and stripe rust diseases under epiphytotic conditions
Loading...
![Thumbnail Image](assets/images/Item.jpg)
Date
2021-08
Authors
Journal Title
Journal ISSN
Volume Title
Publisher
G.B. Pant University of Agriculture and Technology, Pantnagar - 263145 (Uttarakhand)
Abstract
Wheat (Triticum aestivum L.) is foremost and basic cereal crop consumed by approximately 2.5 billion of global population.Among three rusts, stripe rust (Puccinia striiformis West.) and leaf rust (Puccinia triticina Eriks.) are the most important and destructive diseases of wheat in India and elsewhere that affects its yield potential. Although the chemical control of these diseases is known but it is not economic and environmental friendly to be used on a large scale. Frequent breakdown of resistance genes for stripe rust (Yr9 and Yr27) and leaf rust (Lr9, Lr18 and Lr28) led to the investigation of adult plant resistance and slow rust resistance gene which are considered as more durable. The present studies were carried out with the following objectives (i) Screening of exotic germplasms of bread wheat for disease resistance against leaf and stripe rust under epiphytotic conditions and analysis of disease severity with Area Under Disease Progress Curve (AUDPC) (ii) Confirmation of resistance in the phenotypically resistant lines with the use of molecular markers. In the study, 164 germplasm accessions were screened against stripe and leaf rusts during 2019-2020 crop season. Out of one hundred sixty four germplasm accessions, fiftyeight (accession No. 8, 10, 12, 16, 22, 31, 32, 33, 34, 35, 42, 43, 47, 52, 54, 59, 69, 71, 75, 86, 88, 96, 98, 100, 102, 104, 105, 106, 107, 112, 115, 116, 117, 119, 121, 127, 130, 131, 132, 133, 137, 144, 151, 153, 155, 160, 169, 171, 173, 174, 175, 177, 178, 179, 180, 181, 182, 183) were found to be phenotypically resistant to stripe rust and fourteen (accession No. 29, 36, 59, 65, 77, 80, 86, 103, 107, 109, 126, 128, 172, 178) for leaf rust in field conditions during2019-2020 crop season. All the sixty and eighteen accessions which were resistant to stripe and leaf rust respectively, in the field condition also gives lower AUDPC value. Therefore, selection of cultivars having lower AUDPC values is acceptable for practical purposes. Molecular marker characterization revealed that out of 18 accessions which were phenotypically resistant to leaf rust, 13 accessions (accession No. 29, 36, 59, 65, 77, 80, 86, 107, 109, 128, 172, 178, 16) were found possessing Lr19 gene and 8 accessions (accession No. 29, 65, 80, 86, 103, 126, 171, 16) having adult plant resistance gene i.e. Lr67. However, five germplasm accessions i.e. no. 16, 29, 65, 80, 86 have both Lr19 and Lr67 genes. As disease pressure in both the years was quite low therefore, further studies need to be done to confirm the resistance germplasm accessions at phenotypic level for their use in future research programme.