PJB-2018-370
Screening of maize genotypes under northern corn leaf blight (NCLB) epiphtotic at Rawlakot Azad Kashmir
Tahsin Razzaq, Muhammad Fareed Khan, Shahid Iqbal Awan, Huma Tariq and Muhammad Ilyas
Abstract
Northern corn leaf blight (NCLB) is most devastating maize foliar disease in Himalayan region of the world, caused by fungus Exerohillum turcicum. The present investigations were carried out to screen the 30 maize genotypes against NCLB under agro-climatic field conditions of Rawalakot, Azad Kashmir-Pakistan. Artificial inoculation was done at four to six leaf stages during spring 2017. The disease severity of maize genotypes was assessed using 0-5 points scale. Data were recorded on number of lesions on leaf, lesion length, number of infected leaf, number of infected plants, percentage leaf infection, percentage plant infection, disease severity, disease index, disease incidence and area under disease progressive curve (AUDPC). Genotypes had significant differences for NCLB severity and reactions and were classified into resistant, highly resistant, moderately resistant, susceptible and highly susceptible categories. The percent disease incidence ranged from 20-60%, disease index (20-66%), disease intensity (16-34%) and area under disease progressive curve was 22-362%-dsu (percentage development stage unit). Based on disease rating scale and pathological traits, it was reported that three genotypes i.e., Karamat-Bar-25, SZP-13200 and NCEV-1530-11 had lowest values for all pathological traits and severity rating of 5R, 5R and 10R respectively and marked as highly resistant (R) genotypes, whereas three genotypes viz., Soan-3, Ghuari-122 and Kissan-60 were evaluated as highly susceptible (S) within germplasm and had highest values for all pathological traits and severity rating of 90S, 90S and 80S respectively. Fourteen genotypes were moderately resistant (MR), 10 were moderately susceptible (MS) under field conditions. Results suggested that the genotypes found resistant to leaf blight might be utilized in future breeding program. Alternatively, the said promising genotypes might also be used as parents in hybridization in order to transfer the gene for resistance to early blight to existing adapted high yielding cultivars
To Cite this article:
Razzaq, T., M.F. Khan, S.I. Awan, H. Tariq and M. Ilyas. 2019. Screening of maize genotypes under northern corn leaf blight (NCLB) epiphtotic at Rawlakot Azad Kashmir. Pak. J. Bot., 51(5): DOI: http://dx.doi.org/10.30848/PJB2019-5(10)
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