Low Cost Efficient Propagation Techniques in Walnut

 Salient features

• Rootstock of 12 months old with 25–30 mm thickness, one-year-old seedling or shoots of rejuvenated trees.
• Scion 3–4 years old, 15–20 mm thick or active bud with or without wood.
• Height of grafting/budding 15–20 cm above collar region.
• Time: Wedge grafting on rootstocks during middle of March under low cost naturally ventilated polyhouse with 400-gauge thick polysheet.
• Healthy strong stocks (25–30 mm) and fully developed plump scions (15–20 mm) are best and are key to higher grafting success and further plant growth.
• Chip budding during July–August under open field conditions.
• Wrapping with 100-gauge polystrip.
• Scion/buds sprout after 180 days, successful plants shifted to open condition for hardening. Plants are ready for sale/planting after one year.
• Both wedge grafting and chip budding techniques are superior for production of quality walnut planting material.

Performance
• Success of wedge grafting (80–85%) and chip budding (35–40%) varies depending upon material used and efficiency of operation.
• This technology has increased grafting/budding success to as high as 80–85% under polyhouse as against 20–25% under open field conditions.

Impact and benefits
• The grafted/budded walnut trees start bearing at four years as against 8–10 years in seedlings. Grafted/budded trees attain full yield potential 10 years after planting.