Meiotic chromosome preparation techniques of pollen mother cells for laser micro-dissection in Populus spp.

In order to isolate meiotic chromosomes of Populus species meiotic chromosome preparation techniques of pollen mother cells for laser micro-dissection were studied. Pollen mother cells at diakinesis ofPopulus canadensis Moench were used as samples. Two methods were used to prepare meiotic chromosomes： in the first, cell suspensions were dropped on polyethylene-naphthalate or polyester membrane slides which had just been incubated at -20~C; in the second method, cell suspensions were also dropped on polyethylene-naphthalate or polyester membrane slides, but spread with the aid of high temperatures. The cells did not completely spread by the first method and chromosomes at diakinesis could not be individually distinguished. In contrast, well-spread diakinesis chromosomes were obtained by the second method, where chromosomes, connected with their nucleolus, were successfully isolated with the laser micro-dissection system. As well, we discuss the prospect of applications of laser micro-dissection in cytogeneties and molecular genetics in Populus species.

杨树人工林下辽东楤木高效栽培模式

为了提高杨树(Populus spp.)人工林下土地的利用率,解决辽东楤木(Aralia elata)发展缺乏土地问题,本项目将辽东楤木从山区引种到平原杨树人工林下栽植。通过研究不同郁闭度杨树林下辽东楤木的生长节律,不同株行距配置对春菜产量影响和温室反季节水培技术等,形成一整套杨树林下辽东楤木栽培模式。结果表明:1)郁闭度0.6以下的杨树林分,辽东楤木有较高的芽菜产量和较高的生长量,其中辽东楤木株行距1.0 m×1.2 m的配置方式单位面积鲜菜产量最高;2)在株行距4 m×6 m的杨树人工林下,辽东楤木可经营2个轮伐期,辽东楤木鲜菜年产量130 kg/667 m^(2)左右;3)温室反季节生产辽东楤木芽菜是一种可行且经济价值较高的生产方式,可产鲜菜10.0 kg/m^(2)。