夹金山3种同域分布绿绒蒿的传粉生态学研究

A study of pollination ecology of three Meconopsis species with sympatric distribution on Jiajin Mountain

为了揭示夹金山3种同域分布绿绒蒿的传粉生态学特点与繁育系统差异,以全缘叶绿绒蒿、川西绿绒蒿、红花绿绒蒿为研究对象,观测植株的花期物候与传粉媒介,并采用联苯胺-过氧化氢法与氯化三苯基四氮唑(TTC)染色法分别检测柱头可授性与花粉活力。结果表明:1)全缘叶绿绒蒿的花期比川西绿绒蒿和红花绿绒蒿提前近1个月,后两者的花期接近,但三者花期均有重叠。2)3种绿绒蒿柱头可授性持续时间均达5 d以上,且第3至4天时可授性最强。3)在散粉后的8 h内,全缘叶绿绒蒿和川西绿绒蒿的花粉活力随时间延长而下降,红花绿绒蒿的花粉活力呈先升高后降低的趋势。4)全缘叶绿绒蒿花粉胚珠比为990±28,川西绿绒蒿为2050±596,两者之间有显著差异(P<0.05);红花绿绒蒿为1380±202,与前两者无显著差异。且3种绿绒蒿均属于兼性异交。5)3种绿绒蒿有着相同的传粉者麻蝇;其中访问全缘叶绿绒蒿的昆虫种类最多;访问红花绿绒蒿的昆虫比较单一,但数量最多;访问川西绿绒蒿的昆虫数量最少。综上,3种绿绒蒿在繁育系统上表现出差异性:全缘叶绿绒蒿花期和柱头可授期最长,柱头可授性最强,授粉昆虫种类最多,弥补了花粉活力衰减快的缺陷;川西绿绒蒿的花粉能长时间维持高活力但传粉昆虫数量最少;红花绿绒蒿的传粉者有独特的寄生性传粉现象,它们在柱头内产卵,并帮助宿主进行种内传粉,确保了传粉的精确性。

This study investigated the pollination ecology and differences in breeding systems of three Meconopsis species with sympatric distribution on Jiajin Mountain.This study observed and statistically analyzed the flowering phenology and insect pollinators of Meconopsis integrifolia,Meconopsis henrici and Meconopsis punicea and used benzidine hydrogen peroxide and triphenyltetrazolium chloride(TTC)staining methods to detect stigma receptivity and pollen viability,respectively.The results indicated that:1)The flowering period of M.integrifolia began about one month earlier than that of the M.henrici and the M.punicea,and the flowering periods of the latter two were similar,and the three had overlapping flowering periods.2)The duration of stigma receptivity of the three Meconopsis species was more than 5 days,and the plant stigma receptivity was the strongest at the 3rd to 4th day of flowering.3)Within 8 hours after dispersal,the pollen viability of M.integrifolia and M.henrici decreased with time,and the pollen viability of M.punicea initially increased and then decreased.4)The pollen∶ovule of M.integrifolia pollen was 990±28,and that of M.henrici was 2050±596(P<0.05).The pollen∶ovule of M.punicea was intermediate(1380±202),and not significantly different from the other two species.The three species of Meconopsis display facultative outcrossing.5)Three species of Meconopsis had the same pollinator,Helicophagella melanura.M.integrifolia was the species visited by the largest number of insect species,while M.punicea attracted the highest total number of insect visits and M.henrici had the lowest total number of insect visits.The main pollinator of M.punicea was a small parasitic fly which only visits this species and lays its eggs on the stigma.In summary,there were differences among the three species in the breeding system:the flowering period and stigma receptivity period of M.integrifolia were the longest,with the strongest stigma receptivity and the highest number of pollinating insects,which compensated for the rapid decline in pollen viability;the pollen of M.henrici could maintain high viability for a long time,but the number of pollinating insects was the least;M.punicea has a unique pollination mode involving a small parasitic fly.They oviposit within the stigma and assist the host in intraspecific pollination,ensuring pollen reaches flowers of the same species.