Attributes related to seasonal herbage growth in white clover

Abstract

When breeding temperate forage species is investigated, some attributes such as herbage accumulation and seasonal growth patterns have to be considered. To modify some of these traits, knowledge of the detailed process might be useful. In order to evaluate seasonal growth of contrasting white clover populations an experiment was carried out. Treatments were five cultivars and three local populations collected in Argentina. Weekly measures were taken during each season to calculate leaf appearance and flower appearance rates, stolon growing rate and dry matter (DM) net accumulation. Different germplasm of this species have different mechanisms for DM accumulation. Leaf size, more than leaf appearance rate, was the variable with most differences among germplasm and mostly related to dry matter accumulation. During spring and summer, inflorescences production had important effects on growing stolon rate, and differences among germplasm were evident. Some local populations showed favourable attributes that could be useful for breeding. Key words: Trifolium repens L., germplasm, leaves, inflorescences, stolon growth ATRIBUTOS RELACIONADOS AO CRESCIMENTO SAZONAL DE FORRAGEM EM TREVO BRANCORESUMO: Quando o melhoramento de forrageiras de clima temperado é investigado, alguns atributos tais como acúmulo de forragem e padrões de crescimento sazonal devem ser considerados. Para a modificação de alguns desses caracteres, o conhecimento detalhado destes processos pode ser útil. No sentido de avaliar o crescimento sazonal de populações contrastantes de trevo branco, um experimento foi conduzido. Os tratamentos consistiram de cinco cultivares e três populações nativas coletadas na Argentina. Medições semanais foram realizadas durante cada estação do ano para cálculo das taxas de aparecimento de folhas e flores, taxa de crescimento de estolões e acúmulo de matéria seca. Germoplasmas distintos para essa espécie apresentam mecanismos distintos para acúmulo de matéria seca. A característica de tamanho de folha, mais do que a taxa de aparecimento de folha, foi a variável analisada que mostrou as maiores diferenças entre os germoplasmas analisados, além de estar mais relacionada ao acúmulo de matéria seca. Durante a primavera e verão, a produção de inflorescências mostrou efeito importante na taxa de crescimento de estolões e diferenças entre os germoplasmas foram evidentes. Algumas das populações nativas apresentaram atributos favoráveis que podem ser úteis no melhoramento.

Morphoagronomic variation in natural populations of Trifolium riograndense (Burkart)

“…The reasons for this kind of comparison are manyfold: (i) there are no similar studies as the present one for T. riograndense; (ii) both species have similar growing habits, are stoloniferous and perennial; (iii) white clover is widely cultivated around the world and is a well studied and characterized species (Nabinger, 1980;Alcântara and Bufarah, 1988;Mather et al, 1995;Jahufer et al, 2002;Schneiter et al, 2009). For primary stolon length (STL1), in the first evaluation, the higher values were found for accessions 71, 50 (large-leafed group) and 53 (small-leafed group) (15.6, 12.8 and 12.2 cm, respectively), which also presented the higher number of nodes per primary stolon (NN) (10.4, 8.8 and 8.0 nodes, respectively).…”

Under Stressful Conditions, High Cattle Density Maintains White Clover Abundance

“…Therefore, before sampling, the plots had been grazed between 10 and 30 d, according to the position of the plot in the rotation. The sampling dates in each season were based on the results of previous research on changes in the seasonal growth of stolons at the experimental site (Scheneiter and Pagano, 2001b; Scheneiter et al, 2009).…”