SEEDLING VIGOR RESPONSE OF Lotus tenuis POPULATIONS TO CONTRASTING VARIATIONS OF WATER, LIGHT AND NUTRIENT AVAILABILITY

IXTAINA, VANESA Y.; MUJICA, MARIA DE LA MERCED

AGROCIENCIA

Colegio de Postgraduados - Instituci¨®n de Enseñanza e Investigaci¨®n en Ciencias Agr¨ªcolas

Lugar: Ciudad de Mexico; Año: 2010 vol. 44 p. 31 - 41

1405-3195

The intercrop of Lotus tenuis, a strategic legume to improve pasture, is constrained by the limited competitive ability of its seedlings. In this article, we evaluated the influence of the environmental variations of water, light and nutrients on the characters involved in the implantation of populations of L. tenuis, as air dry weight (PSA), number of stems in the crown (Nt), main stem length (Lt) and number of leaves unfolded on the main stem (Nh) in seven populations (P) under contrasting situations of water availability (A), fertilizer (F) and light (S). An effect of P on PSA was detected; the A and S affected all characters, ; F was found to have no effect; increasing PSA, Lt and Nh in flooding conditions showed a tolerant behavior, which can be a competitive advantage over other species under these conditions; shading reduced PSA, Nt and Nh, while causing greater Lt. The interaction A xS (p≤0,001) for Lt and PSA was outstanding; the higher PSA of seedlings subjected to flooding and unrestricted light can be explained by the beneficial effect of abundant water, which prevented potential temporary water stress. Variation among populations was detected only for PSA and there was no significant change in the rest of the characters evaluated, thus limiting the response expectations to selection at the interpopulation level. The strength of seedlings was determined by A and S, which should be taken into account in sowing planning. There was interaction P xS (p≤0.05) for Nt and P xF x S (p ≤0.01) for Lt, although no populations x environments interaction was detected for the seedling vigor estimated by PSA nor for Nh .