Description and Adaptation
Lentil (Lens culinaris L.) is a pulse crop that is part of the Leguminosae family. Lentil plants are typically short but can range from 20 to 75 cm (8-30 inches) in height, depending on growing conditions.
Lentil seed undergoes hypogeal germination, meaning the cotyledons remain below ground. The first two nodes on the stem develop at, or below the soil surface and are known as scale leaves (Figure 1). Scale leaves provide points for possible re-growth, should the plant sustain injury from conditions such as frost, heat canker, wind damage, or defoliation. The third node on the stem has two leaflets and is called the first true leaf. Lentil seedlings can produce a new node every four to five days under good growing conditions. Leaves are about 5 cm long with nine to 15 leaflets. Stipules, much smaller than leaflets, occur in pairs on either side of the leaf axis where it joins the stem. Just prior to flowering, new leaves will develop a short tendril at the leaf tip. At this time, usually around the 12 node stage, the first flower clusters can be seen developing at the base of the leaves.
Lentil plants have an indeterminate growth habit. Plants continue to flower until they encounter some form of stress, such as lack of moisture, high temperatures, or nutrient deficiency.
Flowers are self-pollinated. Flower stalks produce one to three flowers, which develop pods. Pods are less than 2.5 cm in length and usually contain one or two seeds. Vigorously growing lentil plants with adequate space will produce two or more primary shoots from the base of the stem. However, the main contribution to seed yield is made by secondary (aerial) branches that arise from the uppermost nodes of the main stem just below the first flowering node. Flowers that form after the first week of August may not produce filled seeds by harvest.
Figure 1. Lentil seedling
Lentil is a cool season crop with a relatively shallow root system (0.6 metres or 1.97 feet) and is moderately resistant to high temperature and drought. Lentil requires at least moderate moisture; 15 to 25 cm during the growing season to produce a full seed set. Due to its indeterminate growth habit, lentil will often continue to flower as long as growing conditions remain favourable for vegetative growth. Therefore, low moisture or low nitrogen stress is required to encourage seed set and hasten maturity. Excess moisture before the plant is in full bloom promotes vegetative growth, thus delaying and reducing seed set and promoting fungal infections. Lentil grows best on well-drained soil with pH levels of 6.0 to 8.0. It will not tolerate flooding, or soils with high salinity.
In Saskatchewan, lentil is best adapted to the Brown and Dark Brown soil zones but can be grown successfully in the Thin Black and Black soil zones in years with moderate moisture. The development of more determinate red and small green varieties allows opportunity to expand lentil production into less traditional lentil growing areas of the province such as the moist Dark Brown and Thin Black soil zones.