Vol. 10, Issue 9 (2021)

Author(s):
YS Balgude and AP Gaikwad

Abstract:
An experiment was conducted at Agricultural Research Station, Lonavala during Kharif (Rainy) seasons of 2014, 2015 and 2016 to know the influence of appropriate planting time with fungicide sprays for management of blast of rice (Pyricularia oryzae) under natural field conditions. A.R.S., Lonavala is a hot spot for blast of rice. The experiment was conducted in factorial randomized block design with three factors and replications. The factors comprised of five planting dates i.e., 15^th June, 30^th June, 15^th July, 30^th July and 15^th August; two varieties viz., EK-70 (susceptible) and Indrayani (popular cultivar) and fungicidal sprays with carbendazin @ 0.1 per cent and no spray. The rice crop of first planting date (15^th June) had significantly least leaf and neck blast incidences of 7.21 and 28.89 per cent, respectively and leaf blast intensity of 2.05 per cent. However, thereafter blast disease increased linearly up to last planting date (15^th August), wherein incidences of leaf and neck blast and leaf blast intensity were 36.28, 56.00 and 21.67 per cent, respectively. The highest grain (45.72 q/ha) as well as straw (58.08 q/ha) yields were recorded in second planting date (30^th June), then it decreased steadily up to last planting date where grain and straw yields were 23.42 and 30.28q/ha, respectively. The sprays with fungicide carbendazim 50 WP (0.1%) recorded significantly least leaf blast incidence of 15.73 and intensity of 6.58 per cent as well as lowest neck blast (33.94%). Further, the highest grain (62.56 q/ha) and straw (73.39 q/ha) yields were obtained in Indrayani variety of rice when planted on 30^th June with sprays of carbendazim, which had considerably low leaf blast disease incidence of 3.16 and intensity of 0.52 per cent with neck blast incidence of 11.11 per cent. This was followed by planting of Indrayani variety on 15^th July and 15^th June with fungicide sprays. Hence, it is recommended to transplant popular paddy varieties from 15^th June to 15^th July with three sprays of carbendazim @ 10 gm per 10 L water starting first spray at leaf blast appearance, second at sheath formation and third at panicle emergence stage for the effective management of blast disease and increasing the grain and straw yields.