青海高原春小麦留茬高度对后茬绿肥生物量和水分利用效率的影响

针对青海高原地区麦后休闲期长、光热水资源利用效率不高的现状,2019年设置麦后不同留茬高度(0、20、40 cm)复种绿肥田间试验,研究其对箭筈豌豆和毛叶苕子2种复种绿肥的生物量、叶面积指数(LAI)和水分利用效率(WUE)的影响,探讨青海高原春小麦与绿肥的高效复种模式。结果表明,绿肥总干物质量随留茬高度的增加而降低,箭筈豌豆留茬0、20、40 cm干物质总量分别为5756.45、4046.09、3534.09 kg·hm^-2;毛叶苕子分别为3462.69、2642.75、2011.34 kg·hm^-2;根冠比则随着留茬高度的增高而增大,箭筈豌豆留茬0、20、40 cm根冠比由0.043增加至0.057和0.047,毛叶苕子由0.07增加至0.08和0.083;且毛叶苕子的根冠比显著高于箭筈豌豆59.2%。绿肥地上部各器官干重及LAI均随留茬高度的增加而降低,其中,箭筈豌豆LAI随着留茬高度的增加由1.72降至1.34和0.95,毛叶苕子由1.00降至0.77和0.59;茎叶比随留茬高度的增高而增大,箭筈豌豆留茬0、20、40 cm茎叶比分别为0.78、0.89、0.99,毛叶苕子为0.82、0.84、0.86。箭筈豌豆的茎干重、叶干重、茎叶比和LAI分别比毛叶苕子显著高141.1%、135.4%、6.0%和69.6%。两种绿肥WUE均随留茬高度的增加而降低,箭筈豌豆的干物质量和WUE分别比毛叶苕子显著高62.2%和60.0%。麦后不留茬复种箭筈豌豆处理具有最高的生物量和水分利用效率,能够充分利用麦后休闲期光热水资源,是本研究推荐的麦后复种绿肥模式。

陇东地区不同冬绿肥翻压对夏玉米产量和土壤水分的影响

2013-2015年通过对陇东旱塬区实施不同冬绿肥-夏玉米2季轮作体系试验栽培,探讨不同冬绿肥对玉米生长的影响。结果表明,二月兰和冬油菜在越冬期死亡,返春后无地上部生物量,小黑麦生物产出量鲜干重显著高于毛叶苕子。小黑麦处理的玉米籽粒产量显著低于对照,两年平均减产2 604.3 kg/hm^2,而毛叶苕子处理玉米产量显著高于对照,两年分别增产279.8 kg/hm^2和309.3 kg/hm^2。上一年秋季降水少,玉米播前毛苕子和小黑麦处理40 cm土层以下含水量显著低于对照(2014年),反之,则明显高于对照(2015年)。收获期0~100 cm各处理土壤含水量受当季降水影响较大,降雨量大年份(2014年),毛苕子和小黑麦处理40 cm以下土壤含水量较对照低,经过玉米生长消耗,显著低于对照(2015年)。冬绿肥-夏玉米轮作生育期内,0~20 cm、60~80 cm和80~100 cm土层含水量各处理动态变化一致,分别在玉米灌浆期、拔节期和播前最低,而20~60 cm土层,毛苕子和小黑麦处理的含水量在拔节期最低,而其余处理则在灌浆期最低。毛苕子适宜在陇东地区做冬绿肥翻压,有利于实现夏玉米灌浆需水期水分不亏缺和产量的增加。

Effects of Light, Fertilizer and Irrigation on Growth and Physiological Characteristics of Glehnia littoralis

The aim was to promote the cultivation and application of medicinal plants Glehnia littoralis. [Method] Glehnia littoralis was used as experi-mental materials in this study, and orthogonal design was performed to investigate the effects of light, fertilizer and irrigation on the growth of Glehnia littoralis. The biomass, leaf chlorophyl and malondialdehyde （MDA） content were determined to study its response to light, fertilizer and irrigation. [Result] The results showed that the optimum cultivation conditions of Glehnia littoralis were not completely consistent with wild living environments. Lightly shade, highly fertilization （21.38-32.08 g） and proper irrigation （500-750 ml） were suitable for artificial cultivated Glehnia littoralis. Under the condition, the biomass was enhanced, leaf chlorophyl and carotene con-tent were increased, and MDA content changed significantly. Under stress condi-tions, the biomass of Glehnia littoralis reduced, with the decrease of chlorophyl and carotenoid content. The content of chlorophyl a was more sensitive to the variation of light, fertilizer, irrigation and other environmental factors, and MDA content signifi-cantly increased by stress conditions. [Conclusion] This research can provide refer-ence for large-scale artificial cultivation of Glehnia littoralis.