Growth habit is a plant architectural trait in grain legumes with no exception of horse gram [Macrotyloma uniflorum (Lam.) Verdc.]. Determinacy and indeterminacy are the two types of growth habits reported in horse gram. Relative advantages of the two types of growth habit depend on the production systems to which cultivars are targeted. Dependable information on genetics of growth habit provide clues for adopting the most appropriate selection strategy to breed high yielding horse gram varieties with desired growth habit. Taking cues from the past studies, we hypothesize that growth habit in horse gram is controlled by two genes displaying inhibitory epistasis and indeterminacy is dominant over determinacy. To test this hypothesis, we monitored the inheritance of growth habit in F₁, F₂ and F₃ generations derived from two crosses involving parents differing for growth habit. Contrary to our hypothesis, determinate growth habit of F₁s of both the crosses suggested dominance of determinacy over indeterminacy. A good fit of observed segregation of F₂ plants to that of the hypothesized segregation in the ratio of 13 determinate: 3 indeterminate plants, besides confirming dominance of determinacy, suggested classical digenic inhibitory epistatic control of growth habit. These results were further confirmed in F₃ generation based on goodness of fit between observed numbers of plants segregating for determinacy and indeterminacy and those expected in the ratio of 49 determinate: 15 indeterminate plants. To the best of our knowledge, this is the first report on the inheritance of growth habit in horse gram.

生长习性是谷物豆类的植物结构特征，马克[ Macrotyloma uniflorum (Lam.) Verdc.]也不例外。确定性和不确定性是马克报告的两种生长习惯。这两种生长习性的相对优势取决于栽培品种所针对的生产系统。有关生长习性遗传学的可靠信息为采用最合适的选择策略来培育具有所需生长习性的高产马革兰品种提供了线索。从过去的研究中汲取线索，我们假设马革兰的生长习性受两个显示抑制性上位性的基因控制，而不确定性高于确定性。为了验证这一假设，我们监测了 F ₁中生长习性的遗传，F ₂和F ₃代来自两个杂交，涉及生长习性不同的亲本。与我们的假设相反，两个杂交的 F ₁ s 的确定生长习性表明确定性优于不确定性。观察到的 F ₂植物分离与假设的分离以 13 个确定性：3 个不确定性植物的比例的良好拟合，除了确认确定性的优势外，还表明了生长习性的经典双基因抑制上位控制。这些结果在 F _{3 中}得到进一步证实基于观察到的确定性和不确定性分离的植物数量与预期的 49 个确定性：15 个不确定性植物的比例之间的拟合优度。据我们所知，这是第一篇关于马革兰生长习性遗传的报道。