Vol. 11, Issue 12 (2022)

Author(s):
Prem Naresh, Ved Ratan, Upesh Kumar, Traloni Singh and SK Biswas

Abstract:
The domesticated chilli (Capsicum annuum L.) is one of the important vegetables and spices crop among family Solanaceae. Most of the promising chilli cultivars are under a great threat for profitable cultivation due to the attack of several by fungal diseases. The important fungal diseases of chilli are root rot /stem rot. These diseases are responsible for lowering down the yield and quality both. The disease was widely occurring in Kanpur and its adjoining area with the incidence ranging from 12.6 to 59.8 percent (Av. 36.20%). Highest disease incidence (59.8%) was recorded in Sarsaul of dist. Kanpur and lowest in Badokhar, dist. Banda (12.6%) followed by Maudaha dist. Hamirpur (17.4%). The pathogen was able to survive along with diseased plant debris and to cause primary infection. The pathogen surviving in diseased plant debris stored in laboratory condition caused 17.1% infection in seedlings while it infected 29.41% seedlings when plant debris stored under field condition. The seedlings raised in sterilized soil from surface sterilized seeds without mixing plant debris remained healthy. Diseased symptoms were observed on 29.41% seedlings in case of naturally infected seeds while 34.28% seedlings were found infected when raised from artificially inoculated seeds. On the other hand, plants raised from healthy surface sterilized seeds did not develop any symptoms of the disease. This clearly indicated that the diseased seeds served as primary source of inoculums. To ascertain the role of infected soil as primary source of infection, it is revealed that the plants raised in the pots filled with naturally infested field soil and artificially inoculated soil produced stem rot. However, the percentage of plant infection was more in case of artificially inoculated soil than naturally infested field soil. To know the role of seeds in initiation of disease, it was observed that the disease was successfully reproduced from infected seeds sown in sterilized soil. Diseased symptoms were observed on 29.41% seedlings in case of naturally infected seeds while 34.28% seedlings were found infected when raised from artificially inoculated seeds. On the other hand, plants raised from healthy surface sterilized seeds did not developing symptoms of the disease. This clearly indicated that the diseased seeds served as a source of primary inoculums. The highest disease incidence (20-21%) was observed during first week of August, when the average temperature was 31.19 °C (2009-10) & 29.77 °C (2010-11) along with 70.0 and 81.50% relative humidity, respectively in both the year. The disease incidence declined with the decline average temperature along with decrease in average relative humidity. Probably rain fall helped in increasing the relative humidity and also the spread of the disease. To find out the disease resistance reaction, cultivars/ germplsms of chilli were screened under natural conditions and found that, Out of seventy varieties/germplasms screened 04 varieties/germplasms were found to be moderately resistant (MR), 07 moderately susceptible (MS), 23 varieties/germplasm susceptible (S) and remaining varieties/germplasm were found to be highly susceptible(S) under natural conditions. None of the varieties/germplasms was found immune (I) and resistant(R). But in pots experiment (artificial condition), eleven varieties, showing free, resistant and moderately resistant reaction were subjected to further testing under artificial condition of inoculation in the glass house and found that out of 11 varieties /germplasms none of the verieties/germplasm was immune (I) and resistant (R), while 2 varieties /germplasm (Chanchal and A M-1)were found to be moderately resistant (MR), 2 moderately susceptible (MS) and 3 were susceptible (S) and remaining 4 varieties /germplasm were found to be highly susceptible(HS). In pot condition out of 11 selected field trial tested in pots, none of the variety /germplasm was immune and resistant against the test pathogen. The two (Chanchal and AM-1) germplasms were moderately resistant and two (2013 and 8601) were moderately susceptible and rest were susceptible and highly susceptible against the disease. To know the impact of time of planting on disease incidence and yield, chilli seedlings were planted on different time during crop season (1st week of June to II^nd week of August) and observed that when chilli seedlings were planted in the second week of August, the disease incidence was minimum during both the year. The maximum yield was obtained from the seedlings planted in August during both the years. This clearly indicated that with advancement in planting time disease as well as yield potential decreased.