SHARMA, D.P.THAKUR, KISHORE2018-03-142018-03-142018-02http://krishikosh.egranth.ac.in/handle/1/5810041765ABSTRACT The present investigation entitled “Studies on replant problem in peach [Prunus persica (L.) Batsch]” was carried out in a private orchard at village Matnali, Tehsil Rajgarh, District Sirmour and Department of Fruit Science, Dr. Y S Parmar University of Horticulture and Forestry, Nauni, Solan, Himachal Pradesh during the years 2015 and 2016. The objectives of the study were to identify biotic causes of peach replant problem and to study the effects of different soil management practices on plant and rhizosphere related parameters under replant situations. A survey of declined peach orchards was conducted and rhizospheric soil samples were collected from different locations of District Sirmour. The studies were conducted under two different experiments (field and pot-culture), laid out using RBD and CRD, respectively, comprising of 6 treatments including 3 variants viz., soil fumigation, PGPR and biocontrol in 5 different combos and a control (i.e. Recommended package of practices); each with four replications. The process of isolation and identification of fungal pathogens yielded following biotic suspects Aspergillus flavus, Aspergillus nidulanse, Aspergillus niger, Aspergillus oryzae, Penicillium chrysogenum, Penicillium expansum, Penicillium griseofulvum, Alternaria alternata, Acremonium byssoides, Acremonium strictum, Acremonium kiliense, Gilmaniella humicola, Geotrichum candidum, Chaetomium murorum, Phoma destructive, Fusarium oxysporum, Fusarium solani, Mycelia sterilia, Fusarium equiseti and Humicola grisea. Some of these fungi have been previously identified while others represent new candidates. Subsequent Koch’s postulates investigations will assess their possible roles in peach replant disease. Further, in consideration of inference drawn from data with respect to plant and rhizosphere soil parameters, combined treatment (Soil fumigation +PGPR +Biocontrol+25% more of recommended SSP) proved to be a potential agro-technique to combat replant problem in peach, which recorded marked increase in growth and vigour, physiological parameters, foliar and available soil nutrient status as well as soil biological parameters under present investigations.ennullThesis