OBSERVATIONS ON ASPARAGUS SEED YIELD AND YIELD COMPONENTS IN RELATION TO GENOTYPE AND PLANT AGE
Asparagus is presently propagated mainly by seed: seed yield can be, therefore, a critical trait for the success of new commercial hybrids. However, the reproductive aptitude of the presently available parental clones is almost unexplored. In 2003 seed yield, yield components and seed quality were measured on a pilot commercial seed production plant in the Bologna area (Northern Italy). The field was established using the following micropropagated clones: heterozygous female 8 planted in 1998 and 1999, 'G190' and '973' planted in 2000 and 2002, and diplohaploid male '1770' planted each year as pollen parent. Mean seed yield was higher for the older '8' clone (1140 kg ha-1). However, three-year old plants of clone '973' gave higher seed yield (1302 kg ha-1) than the 4 and 5 year old clone '8' plants. Clone '973', gave 126 kg ha-1 seed yield already at the first year. On the contrary, seed yield of 'G190' was almost absent in the first year, reaching 628 kg ha-1 in the third. Total aerial biomass increased with plant age, whereas harvest index reached a maximum at the third year, then decreased. Among seed yield components, the number of stalks per plant was rather variable, but with weak relation to seed yield. On the contrary, the number of berries per stalk seemed to be the main determinant of seed yield. Seed germination attained a maximum for the three year old plants, then decreased; mean germination time was the shortest at the fourth year. Variability was detected among clones for attitude to seed production. Seed yield and quality seemed to attain a maximum for 3-4 year old plants.
D'Antuono, L.F., Neri, R., Pirazzini, M., Casali, P.E. and Falavigna, A. (2008). OBSERVATIONS ON ASPARAGUS SEED YIELD AND YIELD COMPONENTS IN RELATION TO GENOTYPE AND PLANT AGE. Acta Hortic. 776, 299-304
Asparagus officinalis L., breeding, clones, germination, hybrids, propagation, seed quality