Sujan Singh , P. C. Pandey , Ajab Singh , Ram Bahadur , S. N. Mukherjee

Abstract

Symptoms of poplar diseases caused by five major foliage pathogens namely Phyllosticta adjuncta. Myrothecium roridum. Sclerotium rolfsii. Sphaceloma populi and Alternaria alternata are described in this paper. Field observations indicate that P. adjuncta, M. roridum and to some extent S. populi remained on poplar plants in nurseries for longest time while attack of S. rolfsii and A. alternata is confined to lower leaves during monsoon peiod only. Nursery bed with old infected leaves significantly increase the incidence of foliage diseases on paplar plants as compared to beds Cree Crom old leaves. Out of 19 clones of Populus deltoides and 3 of P × euramericana tested for their field resistance against foliage diseases, Done Is found resistant. However attack of foliage pathogens on clones 0-121, G-48, 0-153, G-3 and 6351 of P. Deltoides are significantly less than other clones and hence may be classed as moderately resistance clones. P. deltoides clones, IC, 65/27, 0-100, 6244 and 69/65 are found susceptible and the remaining cIones (Clones 6330, PC-75/6421, 3672, 6358, 6408, 3368, 3231, 2670 and 3196 of P. deltoides and clones 45/51, I-214 and Carppaccio of P. × euramericana) are highly suceptible to foliage diseases. Out of five fungicides namely captaf, dithane M-45, capptacol, blitox and bavistin screened in the laboratory by poisoned food technique. Bavistin at 0.05 per cent (a. i.) and dithane M-45 at 0.25 per cent (a.i.) are effective against both P. adjuncta and M. roridum.

Full Text

     

Sujan Singh , S. N. Mukherjee , Suresh Chandra

Abstract

Treatmont of potting mixture with fungicides (ditbane M-45, blue copper, brassicol and captaf) was observed to delay mycorrhizal development in pine seedlings in experiment conducted in a New Forest Nursery though such treatment did not affect the viability of mycorrhizl inoculum. Treatment of polythene soil with fungicides and mycorrhizal inoculation of the same can therefore be done simultaneously for control of damping off fungi as well as development of mycorrhiza in ischolar_mains of pine seedlings Mycorrhizal development was earlier in pine seedlings pricked in April than in those pricked in November-December.

Full Text

     

B. K. Bakshi , M. A. Ram Reddy , Sujan Singh , P. C. Pandey , S. N. Mukherjee

Abstract

In plantations in the Siwalik Forest Division, U.P. State, raised on site previously occupied by scrub forests, khair seedlings suffered a mortality of 14 per cent, of which 12 per cent could be ascribed due to attack by the ischolar_main parasite, Ganoderma lucidum (Leyss.) Karst. The fungus, as endemic species in the natural forests, built up in the residual stumps which served as infection centres of high inoculum potential. The decayed stumps infected khair seedlings by direct ischolar_main contact and killed them. Removal of residual stumps and ischolar_mains from trenches prior to planting in order to remove the source of infection will bring the disease incidence to the minimum.

Full Text