新牧1号杂花苜蓿开花习性及弹花现象与环境因子的研究

连续2年在新疆呼图壁对新牧1号杂花苜蓿开花习性和弹花现象进行观测,并对影响弹花的环境因子进行分析,结果表明:1)不同年份间及同一年份花期不同阶段的苜蓿有着不同的开花与弹花习性。2004年,3年生植株在初花期每花序开放时间4~7 d,单花寿命为4~7 d,开放后龙骨瓣不能自动弹开;盛花期,每花序1~4 d开放完毕,单花寿命为2~4 h,单花开放后1~2 h龙骨瓣自动弹开,弹花后1~2 h闭合。2)导致单花寿命在不同时期的巨大差异与弹花有关,龙骨瓣弹开后的花会在几小时内闭合而没弹开的花可持续1周不凋谢。3)在访花昆虫无助于弹花的情况下,单花能否发生自动弹花以及弹花的时期,是决定产量的关键因素,而弹花后能否得到传粉昆虫的及时拜访是产量形成的一个必要条件。4)环境因子与弹花密切相关,其中温度、光照强度是影响弹花的重要因素。

A study on the effect of environment factors on flowering behavior and tripping of Xinmu No.1 Medicago lupulina

By observing flowering behavior and the tripping phenomenon of Xinmu No.1 Medicago lupulina the effect of environment factors on tripping were analyzed from 2004 to 2005 in Hutubi County,Xinjiang.The main results were as follows: 1) There were remarkably different flowering behaviors and "tripping" phenomena in the different phases of alfalfa blooms and it varied between years.In 2004,the first florescence of three-year-old alfalfa plants took about 4-7 d for all florets to bloom from bottom to top of each raceme.After blooming,the florets lasted 4-7 d before wilting,and the keel petals could not self-trip.At anthesis,each raceme took about 1-4 d for all florets to bloom and the life-span of the flowers was 2-4 h.After blooming,the flowers self-tripped in 1-2 h and then wilted in 1-2 h.2) The remarkable difference of flower life-span in the different phases of florescence was related to tripping.The flowers wilted in several hours after the keel petal flicked out,whereas if the keel petal was not flicked out or self-flicked the flowers could keep open for a week.3) When the pollination insect cannot trip the flowers,whether the florets can self-trip is the key factor affecting the alfalfa seed yield.If not pollinated after tripping,the flowers can not develop seed pods.Thus the pollination insect is an important factor affecting the seed yield.4) The tripping phenomenon depends on the weather conditions: temperature and illumination are important factors affecting tripping.