A comparison of the yield response of solin (cv. Linola 947) and flax (cvs. McGregor and Vimy) to application of nitrogen, phosphorus, and Provide (Penicillium bilaji)

Field studies were conducted at three locations over three years with Linum usitatissimum L. to determine whether the solin cultivar Linola 947 and th e traditional oilseed flax cultivars McGregor and Vimy, differed in seed yi eld, straw yield and harvest index response to N and P fertilizer and the p hosphorus-solubilizing fungus, Penicillium bilaji, marketed as "Provide". W hile cultivars differed in seed yield, straw yield and harvest index, the r elative performance of the cultivars varied with site and year and did not relate to whether the cultivar was solin or traditional oilseed flax. The d egree and pattern of response of straw yield and harvest index to N and/or P fertilization varied with year and location. Where significant difference s occurred due to P or Provide management, seed yield and harvest index wer e lower and straw yield higher with application of Provide than with applic ation of P fertilizer, indicating that Provide was less effective than P in enhancing seed yield of flax. Solin did not generally differ from traditio nal oilseed flax in the response of seed yield, straw yield and harvest ind ex to fertilizer applications. Response of seed and straw yield to N and re sponse of harvest index to P each differed among cultivars in only one-site year, while an N-by-P-by-cultivar interaction occurred in only one site-ye ar for seed and straw yield. Considering the limited occurrence of cultivar -by-fertilizer interactions, fertilizer recommendations produced for tradit ional flax cultivars should also be applicable to solin cultivars.