Control de malezas de lenteja (Lens culinaris Medik) y su influencia en la produccion de grano en la zona precordillerana de la provincia de Nuble.

The effect of six herbicides and hand weeding on weed control and seed yield of lentils were tested in a trial sown in May, 1988 at El Carmen locality close to the Andes Mountain. 50 km s.e. of Chillan, Nuble. The lentil seed c.v. Constitucion was treated with Rhizobium and Pomarsol before sowing, and 120 kg a.i. P2O5/ha as triple superphosphate applied at sowing. Weed killer applied were Linuron 1 kg a.i., Metribuzin 280 g a.i., Metabenztiazuron 1,4 kg a.i., preemergence/ha. Glifosato 100 g a.i., Bentazon 480 g a.i., Sethoxidim 180 g a.i. post-emergence/ha. Linuron was combined with post-emergence treatments and hand weeding 135 days after seeding. Sethoxidim affect was increased by the addition of a sulfactant. The more dominant weeds at the first accountant in descending order were: Spergula arvensis L. 34%; Vicia sativa L. 33,5%; Anthemis cotula L. 10%; Silene gallica L. 6,5%. The best control was hand weeding, decreasing infection from 90 to 85%, with Linuron and hand weeding, control ranged from 88 to 79%, with Linuron and Bentazon from 71 to 80%, Bentazon from 48 to 70%, with Linuron pre- and post-emergent from 60 to 90% and with Linuron plus Sethoxidim from 78 to 85%, at the first and second inventory, this last after the post-emergent applications. Combined effect of Linuron pre-emergent and Bentazon or Sethoxidim post-emergent were the most effective weed killer controlling 80% and 85%, respectively, Bentazon post-emergent alone applied was also effective controlling 70% weed. The lentil seed c.v. Constitution was treated with Rhizobium and Pomarsol before sowing, and 120 kg a.i. P205/ha as triple superphosphate applied at sowing, because of which, they were always lower than those of the previous years. Effects on seed yield show as better, the treatments Linuron and hand weeding or Bentazon or Metabenztiazuron which gave yields of 5,58; 5,61 and 5,10 qqm/ha, respectively, compared with 3,74 qqm/ha in weeded control. Over it were also the weed-free control, Linuron pre-emergent, Linuron and Glifosato postem. treatments with 4,16; 4,58 and 4,80 qqm/ha, respectively, and under the check; Glifosato, Bentazon, Linuron and Linuron, Metribuzin and Linuron and Sethoxidim, it gave yields of 2.84; 3,66; 2,16; 3,50 and 3,45 qqm/ha, respectively. The weed killer treatments had no notorious effect over the yield components notwithstanding the pods and seed number and seed weight appear significatively increased when Linuron preem. and Bentazon postem. was applied. Correlations between seed yield and some yield components showed significative association of yield with number of branches plants 0,6443, number of pods/plant 0,5110 number of seeds/plant 0,5116 and seeds weight/plant 0,5422.