Effect of solarisation on root knot nematode in seed beds of brinjal

Brinjal or eggplant (Solanum melongena L.) is an important solanaceous crop of sub-tropics and tropics. In Punjab, brinjal is grown in an area of 2790 ha with production of 41250t. Root knot nematode is an important pathogen of brinjal infesting plants in nursery as well as transplants in the field. Protection at nursery level is of utmost importance not only to prevent spread to field but also to develop healthy transplants which can stand environmental stresses. Various non chemical methods have been tried for management of root knot nematode. In the present study, efforts have been made to exploit radiant heat energy of sun for management of root knot nematode in seed beds of brinjal during 2007–10 under field conditions in sick plots. One sq m beds were prepared in an infested soil. These were irrigated and saturated with water before putting white and black sheets. In one treatment, the plots were left uncovered (control). Maximum soil temperature was observed daily in afternoon. In all the four years, the soil temperature in solarised beds was generally higher than unsolarised beds. Observation on gall numbers from 2007 -2010 (pooled data) revealed that maximum reduction in gall numbers was observed in beds which were solarised with white polythene clear sheet (80.2% reduction over control). Solaristion with black polythene sheet also reduced root gall numbers but was found to be comparatively less effective than white sheet. Seedling height and weight was also increased in solarised beds. Weed mass was decreased by 87% over control. In 2011, a trial laid simultaneously in nethouse, polyhouse and open field revaled that under nethouse conditions the rise in temperatures under solarised sheets did not exceed by 5–6 degrees as compared to unsolarised ones. Solarisation appeared to be more useful in open field than in net house and polyhouse conditions.