02214nam a2200265 a 450000100080000000500110000800800410001910000220006024500770008226000470015930000100020650000170021652015420023365000140177565000170178965000100180665000130181665000120182965000240184165000150186565000250188065000160190565000120192165300150193315564441996-09-26       1993    bl uuuu  m   00u1 u    #d1 aANDRADE, R. P. de  aFlowering, seed maturation, and harvest timing of turf-type tall fescue.  a[Corvallis]: Oregon State Universityc1993  a105p.  aPh.D Thesis.  aLack of uniformity in tiller and inflorescence development in tall fescue (Festuca arundinaceae Schreb.) leads to asynchronous seed maturation and difficulty in determining optimum havest time. Little is known about the effects of cultivar, weather, diseases, and fungicides on seed development and maturation in cool season grasses. Several experiments were designed with the general objective of determining seed moisture content at windrowing for achieving maximum yields. Specific objectives were to: a) study daily and seasonal flowering patterns in relation to weather variables; b)determine the normal course of seed development and the effects of propiconazole fungicide (1-[2-(2,4-dichlorophenyl)-4-propyl-1,3-dioxolan-2-yl-methyl]-1H-1.2.4 triazole) and stemrust (Puccinia graminis Pers.graminicola Urban) on seed maturation; and c) compare seed moisture content and growing degree days (GDD) as index of optimum harvesting. The research was conducted with 'Chesapeake', and 'Emperor', turf-type cultivars of tall fescue with differing maturity dates. Hourly and daily flowering intensities were estimated by the amount of pollen collected by Burkard spore samplers. A distinct seasonal peak anthesis occurred only when variation in the daily maximum temperature during the flowering period was small. Calculation of mid-anthesis is a practical and less subjective alternative to visual determination of peak anthesis. A two-year experiment showed that propiconazole has no effect on seed maturation in the absence of stem ....  aflowering  aharvest date  aseeds  aColheita  aFestuca  aFestuca Arundinacea  aFloração  aGramínea Forrageira  aMaturação  aSemente  aMaturation