Spike morphogenesis of winter triticale (X Triticosecale Wittmack) genotypes differing in nutrient utilisation efficiencya)

摘要

Mainstem spike morphogenesis was analysed in two groups of winter triticale (X Triticosecale Wittmack) designated as efficient and inefficient in nutrient utilisation efficiency. Efficient genotypes (MAH 7885-7, MAH 10434-12, LAD 956/84, CZR 134/84) were characterised by a high dry matter weight while inefficient genotypes (CHD 1840/83, CHD 1024/84, LAD 1588/84) showed a low dry matter weight, and a low level of nitrogen and phosphorus utilisation. Defined developmental stages of spike morphogenesis (formation of double ridges, spikelet initiation and differentiation, floret initiation and differentiation, floret growth) in efficient genotypes appeared 10 days earlier than in inefficient ones. Efficient genotypes showed greater number of floret primordia and of fertile florets during spike emergence (heading), greater number of mature florets during anthesis and greater number of grains per spike. Also efficient genotypes had a higher grain weight per spike. Relationships between duration of some crucial stages of spike development (e. g. spikelet phase, terminal spikelet phase, floret phase) and the level of yield components which determined grain yield per mainstem spike in both efficient and inefficient genotypes of winter triticale are discussed.