Características morfofisiológicas de feijão-miúdo sob diferentes densidades de semeadura e intensidade de desfolha

Abstract

Morphogenetic characteristics, structural and productive of cowpea (Vigna unguiculata L.) were evaluated under different plant and defoliation intensities. The experiment was conducted in the area of Embrapa Clima Temperado, Capão do Leão, RS. The treatments consisted of three seeding rates (20, 40 and 60 kg.ha¯¹ of viable pure seed) and three grazing intensities (removal of 50, 63 and 75% forage in relation to pre-cut condition - when the plants reached approximately 40cm in height) during the period November 2013 to March 2014. We used the design of complete randomized block design with four replications. The structural characteristics evaluated included: plant height, main branch length and secondary branches, number of plants per square meter, number of live leaves per primary and secondary branch, branch number, number of plants with secondary branches, leaf fall, number of nodes, leaf / stem and dry matter production. While the morphogenesis was assessed, emergency rates (seedling emergence / day), increased height (cm / day) growth rate (cm / day), onset of leaf (leaves / day) Phyllochron( 1 / leaf appearance rate) and duration of life of the sheet (number of live × Phyllochron leaves). The plant density and defoliation intensity changed morphogenetic and structural characteristics of the bean-kid, however, did not affect the productive performance culture throughout the cycle. Thus, the low seeding density (20 kg.ha¯¹), regardless of defoliation management (lowering between 50 and 75% of pre-cutting time) was enough to prevent the larger forage crops throughout the production of cowpea.