ChileanJAR

During three years dry matter (D.M.) yield of Lotus tenuis in pure and mixed stands under cutting conditions were evaluated. Purposes were: quantify the annual D.M. yield and its seasonal distribution, analyze the botanical composition dynamics of mixtures, and determine yield stability through time. The experimental design was a randomized block with 4 replications and 5 treatments: pure L. tenuis sown at two densities (Ld1-Ld2) and L. tenuis in mixtures with Thinopyrum ponticum (LA), Festuca arundinacea cv. Maris Kasba (LMK) or Festuca arundinacea cv. El Palenque (LEP). Ld1 and Ld2 showed no difference(P>0.05) in total annual yield (henceforth Lp=Ld1-Ld2mean yield). In the first year total yield showed no differences between mixtures, being lower for LA and LEP in the third year (LA =7,438 year 1; 4,208 year 3; LMK =5,776 year 1; 5,651 year 3; LEP =7,431 year 1; 5,622 year 3). Seasonal yield of all treatments was concentrated during spring and summer. During the three years, pure L. tenuís over yielded (P<0.05) mixed stands, though decreasing through time in all treatments (Lp =8,492 year 1; 1,729 year 3; L. tenuís in mixtures =3,414 year 1; 1,079 year 3). The grass component did not decrease in any mixture through time. In pure stands, not sown species proportion increased significanly through time while decreasing in mixtures. It is concluded that yield was higher and more stable in mixture than in pure stands. Under this kind of defoliation regimen the initiallegume contribution to phytomass would drasticalJy decrease in the short termo Not sown species abundance was important principally in pure stands. Results suggest the convenience of sowing the legume in mixtures with grasses for the conditions of this essay.