施肥对芹菜生长及硝酸盐含量的影响

在砂质潮土上研究了不同施氮量和生物菌剂接种对芹菜生长及硝酸盐含量的影响。结果表明,无论是否接种生物菌剂,增施氮肥均有利芹菜产量的提高。在等氮量条件下,接种丛枝菌根真菌Glomus mosseae “93”显著促进芹菜产量的提高。随着施氮量的增加,芹菜硝态氮含量大幅增加,Vc含量呈下降趋势。为获得相同的产量目标,通过接种丛枝菌根真菌Glomus mosseae “93”可以显著降低氮肥的施用量,并因而大幅减少芹菜硝酸盐的累积。     

不同育苗方式对茄子幼苗生长的影响

为筛选出适合茄子幼苗生长的最佳育苗方式,研究了营养钵、穴盘育苗和普通苗床育苗3种育苗方式对茄子幼苗生长动态的影响.结果表明,采用营养钵培育的幼苗茎叶鲜重、根鲜重、单株干重、茎粗、壮苗指数等生长指标最好,其次是穴盘育苗,最差的是普通苗床育苗.生产上茄子的育苗方式建议采用穴盘育苗.     

柴达木地区新疆杨扦插育苗试验

通过新疆杨插穗催根不同处理方法和扦插时间对比试验,总结出柴达木地区新疆杨扦插育苗过程中最佳的插穗催根方法和扦插时间。     

寡聚酸钾对豌豆幼苗生长的影响

研究了不同浓度寡聚酸钾对豌豆幼苗生长、根系活力和光合色素含量的影响。结果表明:0.1~10mg/kg的寡聚酸钾均能显著促进豌豆幼苗的生长,提高根系活力和光合色素的含量。1mg/kg的寡聚酸钾对豌豆幼苗根系活力、光合色素含量以及生长指标的促进作用最为明显。     

光辐射强度对侧柏油松幼苗光合特性与水分利用效率的影响

 探讨不同土壤水分条件下光辐射强度对侧柏和油松苗木光合特性与水分利用效率的影响规律,可为林木栽培和管理提供科学依据。在黄土半干旱区,采用人工控制土壤水分的方法,利用模拟光源研究了侧柏和油松苗木的净光合速率、蒸腾速率、水分利用效率和胞间CO2浓度随模拟光辐射增强的变化规律。结果表明:在模拟光辐射为0～2200μmol/（m2.s）的范围内,侧柏和油松叶片的净光合速率、蒸腾速率和水分利用效率均随光辐射强度的增强而增大,但光辐射强度进一步增强,侧柏和油松净光合速率和水分利用效率呈下降趋势;在同样土壤水分条件下,侧柏净光合速率、蒸腾速率和水分利用效率高于油松,侧柏光饱和点高于油松,而侧柏光补偿点低于油松,侧柏光能利用率高于油松;随着土壤水分的增加,侧柏与油松净光合速率、蒸腾速率和胞间CO2浓度升高,而水分利用效率降低。在土壤含水量为7.90%、13.00%和19.99%条件下,侧柏光饱和点分别为1275、1 450和1 675μmol/（m2.s）,光补偿点分别为4225和13μmol/（m2.s）,由光饱和点对应最大净光合速率分别为3.04、4.06和5.53μmol/（m2.s）;在土壤含水量为7.83%1、3.04%与20.15%条件下,油松光饱和点分别为11001、325和1500μmol/（m2.s）,光补偿点分别为60.30和23μmol/（m2.s）,由光饱和点对应最大净光合速率分别为1.08、3.35和4.36μmol/（m2.s）。     

杂种大花万寿菊试管苗繁殖

利用组织培养技术繁殖引进的杂种大花万寿菊获得成功,在诱导侧芽时,利用６－卞基腺嘌呤（６－ＢＡ２．５ｍｇ／Ｌ）和玉米素（ＺＴ２．５ｍｇ／Ｌ）ＺＴ对侧芽的诱导效果好于６－ＢＡ,诱导生根的培养基分别为（１）１／２ＭＳ;（２）１／２ＭＳ＋ＮＡＡ０．５ｍｇ／Ｌ;（３）１／２ＭＳ＋ＮＡＡ１ｍｇ／Ｌ;（４）１／２ＭＳ＋ＩＢＡ０．５ｍｇ／Ｌ;（５）１／２ＭＳ＋ＩＢＡ１ｍｇ／Ｌ．ＩＢＡ可以促进万行区形成不定根,质量     

Blight of conifer seedlings caused by Colletotrichum gloeosporioides

In a growth chamber experiment, 70-day-old seedlings of 10 conifer species were inoculated with Colletotrichum gloeosporioides conidia to determine the host range of the fungus. Based on the percentage of seedlings affected and the disease severity on individual seedlings, the order of most to least susceptibility was: western hemlock (WH), mountain hemlock, western larch, Sitka spruce, Engelmann spruce, Douglas-fir (coastal form, then interior form), white spruce and ponderosa pine; lodgepole pine and western red cedar remained unaffected. Inoculation of WH needles showed that within 24 h C. gloeosporioides conidia germinate and appressoria (penetration structures) form. A growth chamber study demonstrated that the pathogen can infect WH at needle wetness periods as short as 15 min; number of needles affected was higher at 0.5 h, but did not increase further even when wetness was extended up to 8 h. The results are discussed in relation to blight management of greenhouse-grown conifer seedlings.Portion of a Bachelor of Science (Honors) thesis, Department of Biology, University of Victoria, Victoria, British Columbia.     

CO2加富对茄子穴盘幼苗生长的影响

研究了572,859,1145 μL·L-13种不同体积分数的CO2加富对茄子穴盘幼苗的影响.姑果表明,与对照相比,CO2加富施肥使茄子幼苗的株高及茎粗明显增大,增加了干物质积累量和叶面积;叶绿素含量增加,增强了光合作用;茄子幼苗的根系活力升高;第14天时,可溶性糖含量分别增加88.07%,119.51%和133.48%.茄子幼苗在施用859 μL·L-1CO2时品质优于其他处理,可作为该茄子幼苗适宜的CO2体积分数,1145μL·L-1次之.     

北京地区玉米就地加代技术的初步研究

1984—1986年在北京进行早熟、中早熟玉米一年两季加代试验.试验结果表明.第一季加代采用早春(3月上旬—下旬)温室育苗,3月末至4月上旬移栽到塑料薄膜复盖的阳畦、小棚或大棚;以及3月下旬直播于铺设电热线的阳畦,大棚等增温保温措施,早熟、中早熟玉米自交系和育种材料。可于5月下旬进入抽雄、吐丝、散粉期,7月上旬末以前收获授粉后25—30天果穗,种子发芽率可达到80%以上,第二季加代采用上季25—30天嫩粒,经2%H_2O_2浸种24小时,于7月上旬播种(气温偏高年份还可适当延迟播种),在大田条件下,8月下旬可进入抽雄、吐丝、散粉期,授粉工作可进行到9月上旬末,10月底以前收获的种子,发芽率一般达80%左右,高的达90%以上.H_2O_2处理玉米种子可明显加速种子发芽,促进幼苗生长.采用了短日照处理(8—10小时日照)生育后期叶面喷磷钾肥和乙烯利等促进早熟措施,对本试验成功实现一年两季加代,均取得了一定效果。     

Comparison of the response of ion distribution in the tissues and cells of the succulent plants Aloe vera and Salicornia europaea to saline stress

There exists a great variability among plant species regarding their sensitivity and resistance to high salinity in soil, and most often this variability is related with the ability of a particular plant species to regulate ion homeostasis and transport. In this study, we have investigated the effects of NaCl on growth rate, water status, and ion distribution in different cells and tissues of two succulent plants, Aloe vera and Salicornia europaea. Our results showed that the growth of A. vera seedlings was significantly decreased in response to salinity. However, the growth of S. europaea seedlings was greatly stimulated by high concentrations of NaCl. Under saline conditions, S. europaea seedlings maintained K⁺ and Ca²⁺ uptake in roots and showed a higher root‐to‐shoot flux of Na⁺ and Cl^– as compared to A. vera. Despite great accumulation of Na⁺ and Cl^– in photosynthetically active shoot cells in S. europaea, its growth was enhanced, indicating S. europaea is capable of compartmentalizing salt ions in the vacuoles of shoot cells. Aloe vera seedlings, however, showed a low transport rate of Na⁺ and Cl^– to leaves and suppressed uptake of K⁺ and Ca²⁺ in roots during NaCl treatment. Our results also implicate that A. vera may be able to accumulate Na⁺ and Cl^– in the metabolically inactive aqueous cells in leaves and, as a result, the plant can survive and can maintain growth under saline conditions.