天祝高寒草地马蔺的开花物候及繁育系统研究OA

[Objective]This study aimed to characterise the flowering phenology and breeding system of Iris lac-tea.[Method]A natural population of Iris lactea in the Tianzhu alpine grassland was selected as the study material.Flowering phenology was monitored,and controlled pollination experiments were conducted to assess the breeding system.[Result]Under natural conditions,Iris lactea blooms from June to July.The population flowering period lasted approximately 33 days,with a peak flowering period of about 15 days.Individual flowering duration ranged from 19 to 27 days,with inflorescence longevity of 114～144 h and single-flower longevity of 55～75 h.Two daily flowering peaks were observed,occurring between 10∶00-11∶00 and 16∶00-17∶00.Floral traits exhibited consider-able variation,with a coefficient of variation of 36.73%,and stamens positioned approximately 3 mm from the stigma.No fruit set occurred in treatments involving bagging without pollination or self-pollination under isolation.The highest fruit set was observed under artificial cross-pollination(97.5%),followed by artificial self-pollination(95.0%),both exceeding that of the control.Fruit set under bagging without pollination was significantly lower than in the control.[Conclusion]This Iris lactea population exhibits a short and concentrated flowering period and a mixed mating system dominated by outcrossing.The species lacks apomixis.Reproductive success under natural con-ditions may be constrained by pollen limitation and insufficient pollinator activity.