Effect of cutting height on the yield and straw quality of lentil and on a succeeding wheat crop

Abstract

Lentil (Lens culinaris Med.) seeds are an important source of protein in the human diet, while the straw is widely used as animal feed in the Mediterranean region and West Asia, but production is declining due to the high cost of hand-harvesting. Investigations were conducted during 1984–1985 and 1985–1986 at Tel Hadya, North Syria, to assess the yield losses in seed and straw when lentil cultivars of differing plant type were harvested with a double-knife harvester at various heights above ground-level, compared with traditional hand-pulling. Averaged over both seasons, respective losses were 10.1%, 14.8% and 19.5% in seed yield and 16.1%, 39.9% and 45.1% in straw yield, for cutting lentil at ground-level and at 5 and 10 cm above ground, compared to hand-pulling. Digestibility of straw, and its protein percentage, increased with height of cut. Percentage losses in seed and straw yields were least in the tall upright cultivar ILL 8, and greatest in the spreading-type ILL 4400.

The residual effect of the different heights of cut and cultivars of lentil on the succeeding wheat crop, given 0 and 60 kg N ha−1, was investigated during the 1986–1987 season. Method of harvest of lentil in 1985–1986 did not significantly influence the total biological and seed yields of a succeeding wheat crop in 1986–1987. Nitrogen applied at 60 kg ha−1 on the wheat crop in 1986–1987 tended to increase total biological yield, but significantly decreased harvest index and seed yield.