Relationship of susceptibility and growth stages of plant for development of epidemic of sheath blight in rice

The present paper deals with most susceptible growth stage of rice with different farms and quantitiy of inoculum for development of sheath blight of rice by Rhizoctonia solani.Among seven different growth stages of rice crop i.e. seedling, initial tillering, maximum tillering, boot leaf, panicle emergence, flowering and dough stage, the flowering stage was found to be most susceptible and highly prone for sheath blight development, while seedling stage was found to be least susceptible and with low proneness for disease development. Disease severity, number and length of lesions get increased with the increasing crop growth stages up to flowering stage and thereafter disease severity decreases with the increases in further growth stages of rice plant. Among four different growth stages of the pathogen (inoculum capacity) i.e. five days old mycelium, seven days old mycelium, milky sclerotial stage and mature sclerotial stage which were inoculated at maximum tillering stage of rice plants, five days old mycelial inoculum was found to be most virulent. Disease severity decreased and incubation period increased with further ageing of inoculum. Among five different amount of inoculum (inoculum density) i.e. 0.20 mg, 5.50 mg, 6.00 mg, 7.00 mg and 8.00 mg of sclerotial inoculum, which were inoculated at maximum tillering stage of rice plants, highest disease severity and minimum incubation period was observed with 8.00 mg amount of sclerotial inoculum. Whereas, least disease severity and longest incubation period was observed when inoculation was done with 0.2 mg of sclerotial inoculum

Genetic variability in sugarcane (Saccharum spp. hybrid) genotypes through inter simple sequence repeats (ISSR) markers

In the present study, 14 sugarcane (Saccharum spp. hybrid) genotypes were used for genomic diversity analysis based on nineteen inter simple sequence repeat (ISSR). These nineteen sets of ISSR markers generated a total of 164 discernible and reproducible bands including 109 polymorphic and 55 monomorphic bands. The unweighted pair group method with arithmetic average (UPGMA) analysis revealed three distinct clusters: I, II and III within the 14 genotypes. The polymorphic information content (PIC) value per locus ranged from 0.14 (UBC811) to 0.53 (ISSR1) locus with an average of 0.42 for all loci. The range of genetic distance or coefficient of similarity among sugarcane genotypes varied 0.14 - 0.78. The analysis of these similarities matrix revealed that greater similarity between CoS03234 and CoSe1424 (0.78), and lowest similarity between CoS03234 and Co0118 (0.14). The knowledge gained in this study would be useful to future breeding programs for increasing genetic diversity of sugarcane varieties and cultivars to meet the increasing demand of sugarcane cultivation for sugar and bio energy uses

Off Season Fruits in Poly-houses

47-48IF you are yearning for your favourite vegetable or fruit that is not available during the season, poly-houses could be the answer to your predicament

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