Management of Irrigated Lentil

Introduction

The Canada-Saskatchewan Irrigation Diversification Centre has evaluated breeding lines, varieties, and appropriate management practices for irrigated lentil production since 1987. A brief summary of research conducted from 1987 through 1993 is presented.

Variety Evaluation

Several registered varieties and a number of advanced breeding lines were tested under irrigation to identify early maturing, disease tolerant or resistant material of suitable plant type and growth habit. The more vigorous, later-maturing Laird lentil consistently produced lower seed yields than the early-maturing, less vigorous Eston, or the intermediate type CDC Richlea (Table 1).

Seeding Rate and Row Spacing

The effects of seeding rates and row spacing on yield of Eston lentil under irrigation were studied in 1990 and 1991 (Table 2). Seeding rates from 100 to 200 plants/m2 had no significant effect on yield in 1990 or in 1993. In 1991 a progressive increase in yield was observed up to a seeding rate of 175 plants/m² (50 - 55 lb/ac.).

In 1990 and 1991, the 10 cm (4 inch) row spacing produced slightly higher yields of Eston than the 20 cm (8 inch) spacing, but the increases were not statistically significant. In 1993 the yield of Eston was 16% higher in 20 cm rows than in 40 cm (16 inch) rows.

Irrigation Scheduling

Research work and producer experience has shown that overwatering can reduce lentil yield. Moisture stress, particularly during the reproductive stage can also reduce yield. Judicious use of irrigation can help ensure consistent yields by alleviating moisture stress.

Work in Alberta indicated that Eston produced highest yield at a total water use of 260 – 300 mm (10 – 12 inches). For Laird the optimum water use was 190 – 280 mm (7.5 – 11 inches).

Results of irrigation scheduling work at SIDC are summarized in Table 3. In drought years lentil yield was increased substantially by irrigation. In wet years the benefit of irrigation was less. In years of abundant growing season precipitation, irrigation resulted in excessive vegetative growth and increased disease incidence which caused considerable yield loss.

For example, in the dry year of 1989 which received only 95 mm (3.75 inches) of rain, irrigated plots of Eston yielded 5 to 6 times more than the dryland plots (Table 3). In 1990, which received 230 mm (9 inches) of rain, supplemental irrigation of Eston produced a 19% higher yield than the dryland crop. In the cool, wet year of 1993, even moderate irrigation of 75 mm (3 inches) caused severe yield reduction. The decrease was more pronounced for Laird than for Eston.

During the wet 1993 season, irrigation at the flowering stage reduced seed yield of Eston by 22% compared to treatments that did not receive water at flowering. Lentil should not be irrigated during flowering and pod formation in wet years.

Diseases

Diseases such as aschochyta blight, anthracnose, and sclerotinia stem rot can cause severe damage to lentil under high moisture conditions. The effect of irrigation on the incidence of disease was studied from 1991 through 1993. Irrigation tended to increase disease levels. In 1993, for example, anthracnose had infected 40% of dryland Eston plants and 65% of irrigated Eston lentil plants. For CDC Richlea the anthracnose incidence was 18% on dryland and 28% on irrigated plots.

Results of studies:

• Under irrigation, Eston and CDC Richlea produced higher seed yield than Liard.
• Seeding rate and row-spacing recommendations for dryland production are suitable for irrigated production.
• Over-irrigating in wet years or at flowering can reduce yield considerably.
• Under high moisture conditions, Eston and Laird were more susceptible to diseases then CDC Richlea.

NS = not significant
* = significant at 5 % level; LSD = 570
** = significant at 5 % level; LSD = 275

For more information, please contact:
Canada-Saskatchewan Irrigation Diversification Centre
901 McKenzie St. S
Outlook, Saskatchewan
S0L 2N0
Phone: (306)867-5400
Fax: (306)867-9656
E-mail: csidc@agr.gc.ca