Studies on Stemphylium leaf spot and Leptosphaerulina pepper spot, two foliage diseases of lucerne : a thesis presented in partial fulfilment of the requirements for the degree of Masterate of Agricultural Science at Massey University

Abstract

Over recent years the area of lucerne (Medicago sativa L.) grown in New Zealand has rapidly increased (Table 1) as farmers and commercial firms have realised the many and varied virtues of this crop in farming enterprises. TABLE 1. Areas of lucerne grown in New Zealand used for hay, silage and seed production. Year Area (acres) Authority 1953-59 144,516 N.Z. Year Book, 1963 1963-64 164,860 N.Z.Year Book,1969 1968-69 202,770 N.Z. Year Book, 1971 1970-71 300,000 Meeklah & Allen, 1971 Lynch (1967) estimated that if the present trend continued a lucerne area of at least 300,000 acres could be expected by 1977. However, this area was attained by 1970, and the increased rate of expansion can be accounted for in several ways: 1. Due to its agronomic features lucerne is primarily grown in free-draining soils subject to an unreliable summer rainfall, so ensuring a continued feed supply over this period. 2. Lucerne has a greater versatility than most crops within a farming enterprise in that it can be utilised in several ways; for example, hay and silage, grazing, seed production, and more recently for lucerne meal or pellets, and protein extraction. 3 A gross margin analysis of lucerne as a cash crop indicates a return comparable with, or better than, such other popular crops as wheat or peas (Lamb, 1969; Tocker, 1970; Anon, 1970; Anon, 1972). [From Introduction]