Studies on the pycnidial formation by Macrophomina phaseoli (Maubl.) Ashby. Development of pycnidia and pycnidiospores

Summary An account on the pycnidial development of eight isolates ofM. phaseoli — five from cotton and the other, one each from castor, groundnut and sesame and also from a culture medium has been given. The pycnidial development ofM. phaseoli from cotton on a culture medium is extremely rare and pycnidia developed were having the outer wall consisting of only one layer of thickened cells and no clear ostiole. In the other isolates, all from the hosts, there were no differences in the development of pycnidia and pycnidiospores. All the isolates were true to the type speciesM. phaseoli.