~ 128 ~ The Pharma Innovation Journal 2018; 7(10): 128-130 ISSN (E): 2277- 7695 ISSN (P): 2349-8242 NAAS Rating: 5.03 TPI 2018; 7(10): 128-130 © 2018 TPI www.thepharmajournal.com Received: 27-08-2018 Accepted: 28-09-2018 Sukram Thapa Department of Plant Pathology, BCKV, Mohanpur, Nadia, West Bengal, India Prateek Madhav Bhattacharya Department of Plant Pathology UBKV, Pundibari, Coochbehar, West Bengal, India Deewakar Baral Department of Plant Pathology, BCKV, Mohanpur, Nadia, West Bengal, India Correspondence Sukram Thapa Department of Plant Pathology, BCKV, Mohanpur, Nadia, West Bengal, India Correlation of different traits of wheat with resistance to spot blotch disease Sukram Thapa, Prateek Madhav Bhattacharya and Deewakar Baral Abstract Spot blotch of wheat is caused by Bipolaris sorokoniana is one of the major disease of wheat which causes a considerable yield loss throughout the wheat growing areas in the world. Other than spot blotch this pathogen is reported to cause common root rot, foot rot, seedling blight and seed rot disease. Growing of resistant varieties and varieties with different phenological traits related with resistance to spot blotch disease can be an effective way of managing the disease. In this experiment different phenotypic traits for resistance to spot blotch were observed to explain the disease. Among the different phenotypic traits observed, phenological traits (onset of reproductive phase and maturity), symptomatological trait (lesion number), morphological trait (plant height), physiological trait canopy temperature (AUCTPC), chlorophyll content (AUSDC) and stay green property of the genotypes were found to explain 61 percent in the disease variation. Therefore these traits can be used as diagnostic traits for selecting spot blotch resistant wheat genotypes. Keywords: Bipolaris sorokoniana, spot blotch, wheat, resistance, phenological traits. 1. Introduction Wheat is a cereal grain which comes under the order Poales, family Poaceae, sub family Pooideae and have different species under the genus Triticum. Considering its nutritious value wheat is consumed throughout the world and looked as most important cereal crops in the world and occupies the largest area under cereal. In India it is the second most important staple cereal food after rice. Cultivation of wheat first started about 10,000 years ago, as part of the ‘Neolithic Revolution’, which leads to the shifting from gathering and hunting of food to well settled agriculture. Cultivation of wheat in India started around 5000 years ago (P. R. Shewry2009) [13] . In India wheat is grown as a rabi season crop. Being most important cereal crop wheat production and productivity are greatly challenged by different abiotic and biotic stress. Among the biotic stress Spot Blotch is gaining much importance and a major limiting factor for wheat productivity in warm and humid regions and more severe following rice wheat cropping system. The disease is caused by the pathogen Bipolaris sorokinian (Sacc.) Shoemaker (syn. Helminthosporium sativum teleomorph: Cochliobolus sativus). The occurrence of spot blotch disease was first reported by Mohy in the year 1914 but it was not regarded as an important pathogen in South Asia before the Green Revolution (Saari, 1998; Chaurasia et al., 1999) [11, 2] . Spot blotch pathogen is a hemibiotrophic phytopathogenic fungus and causes seedling blight, foliar blight/spot blotch, common root rot, head blight and black point in wheat, barley, other small cereal grains and grasses (Zillinsky, 1983; Wiese, 1998) [19, 16] . Global estimate indicates that 25 million hectares of wheat is affected by spot blotch (van Ginkel and Rajaram, 1998) [15] , out of which India alone accounts for 9 million hectares, mostly in the rice wheat cropping system in the north eastern plain zone (Nagarajan and Kumar 1998) [9] .Yield losses due to spot blotch of wheat are reported to range from 15.5 (Saari, 1998) [11] to 100% under severe conditions of infection (Mehta, 1993). Therefore the management of spot blotch disease is very important and the best approach to manage the disease can be obtain by developing resistant varieties. There are Reports of the presence of monogenic (Arney, 1951, Wilcoxson et al., 1990) [1, 17] and polygenic (Griffee, 1925, Steffenson et al., 1996) [4, 14] types of resistance to spot blotch disease. Different physiological, morphological, phenological and symptomatological traits has been reported to be related with resistant to spot blotch disease by different researchers which can be used in breeding for resistance.