Clubroot is a devastating disease of crucifers throughout the world. It is caused by a soil-borne obligate phytoparasite, Plasmodiophora brassicae Wor. Plant affected by this disease shows flagging of leaves, unthrifty growth, and even premature death. When uprooted, root shows characteristic symptom of hypertrophied club-shaped root system. Several biotic and abiotic factors affect the disease severity. Biotic factors include spore load in soil and virulence of pathogen, whereas abiotic factors generally include soil environmental factors such as soil temperature, soil pH, soil moisture, and soil type. Pathogen survives, for substantial period of time in absence of host, through its double-walled resting spores in soil or crop debris. Temperature affects spore germination, occurrence, and pathogen proliferation. Acidic soil reaction is crucial for pathogen to proliferate, metabolize, secret enzymes, and to complete lifecycle. All type of soil textures favor disease; however, severity differs with type of soil and soil organic matter content. Soil moisture provides platform to move bi-flagellated zoospores to infect root hairs of crops. Root hair infection is commensurate with inoculum density or spore load in soil. Immediate management strategies entail cultural practices, use of biocontrol agents, and application of chemical as last resort. Trichoderma spp., Pseudomonas fluorescens, Bacillus subtilis, and Gliocladium catenulatum are potential biocontrol agents. Flusalfamide, Fluazinam, and Cyazofamid are some common chemicals used to control clubroot. Soil carried by farm implements, human body, irrigation water, and flood can be potential source of pathogen. The risk of clubroot can be reduced by ensuring phyto-sanitory measures, destroying host crop debris, regular scouting, growing resistant cultivars, avoiding acidic soil reaction, eliminating weedy hosts, and reducing soil movement.

Grafting is a successful method of propagation of cultivated apple (Malus domestica Borkh.). However, the most suitable grafting date and wrapping material have not been well understood. The field experiment was conducted to study the effect of grafting dates and wrapping materials on grafting success of royal delicious apple at Horticulture Research Station, Jumla of Karnali Province. The experiment was laid out in Two Factorial Randomized Complete Block Design (RCBD) with four replications. The treatments span four grafting dates (25th February, 4th March, 11th March, and 18th March of 2018) and two wrapping materials (grafting tape and normal plastic). Data for different parameters were taken at 60 days after grafting (DAG) and 90 DAG. The results revealed that the treatment of grafting date March 11 and grafting tape recorded minimum days (24.38) for first sprouting, minimum days (28.88) for 50% sprouting, maximum success percentage (92.51%), maximum increment in length (54.88 cm), and highest number of fully opened leaves (23.62) of grafted scions at 90 DAG. The results indicate that the suitable time for grafting of royal delicious apple is between 1st and 2nd weeks of March and suitable wrapping materials is grafting tape. The orchard or nursery owners of Jumla are suggested to carry out grafting in first half of March and to use grafting tape as wrapping material of graft.