More disease-resistant and drought-tolerant cultivars of lablab, an annual tropical legume that could fit will into Texas forage-production systems, will be field-tested this year by Gerald Smith, Texas A&M AgriLife Research plant breeder.
If all goes well, Smith expects new cultivars to be ready to start the release stage in three years. The approval and subsequent release of seed to seed-production companies usually takes another two years.
Smith has worked with lablab for 10 years and developed Rio Verde lablab, released in 2006.
Rio Verde is planted in May, will start flowering in late August and continue producing forage until first frost. Its leaves’ crude protein averages 25% or higher; its stems provide around 12% crude protein.
As good as Rio Verde is, there is a need for an earlier-flowering and more disease-resistant variety, Smith says.
Smith crossed existing anthracnose-resistant lines with small-seed, deep-rooting types that are closely related to wild lablab lines. “The parents that we crossed are quite different. What we are doing now is selecting for flowering times that will fit Texas.”
The most promising progeny will be field-tested in 2013 and desired traits will be selected.
“We need a new forage crop in Texas that fits our seasons and works for us in the summer,” Smith says. “We have a lot of summer annual grasses, but we need a forage legume that works in the summer like those grasses.”
Lablab fits that need very well, he adds. Cattle readily graze it and get good weight gains from the drought-tolerant crop. Wildlife benefit from the legume and, because it is a legume, it fixes its own nitrogen. Unlike many other legumes, such as cool-season clovers, lablab seed can be produced in Texas.
“Lablab is deep-rooted and drought- and heat-tolerant, but does require soil moisture to germinate and establish,” Smith says. “This does narrow the utility of this plant to eastern and central Texas where annual rainfall is at least 30” per year.”