共查询到19条相似文献,搜索用时 93 毫秒
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砧木用南瓜原产日本,传入我国后,经过改良,现在成为许多蔬菜品种良好的嫁接砧木,青岛农科院培育的青研砧木一号就是其中之一,近几年在全国各地推广应用面积发展很快。它的特点是抗病性强、根系发达、嫁接前期有较好的低温伸长性和坐果率,与品种有较好的嫁接亲和性和共生亲和性。但是青研砧木一号杂交制种经常受气候的影响:定植较早,前期霜冻危害严重;定植较晚,后期高温影响坐瓜。 相似文献
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<正>上世纪80年代,国外种子商通过我国农业管理部门在唐山市建立了西、甜瓜嫁接砧木——白籽南瓜杂交制种基地,进行专业化生产,产品全部外销。几年后该项任务取消,而亲本材料得到保存。随着国内西、甜瓜嫁接栽培的发展,使白籽南瓜杂交制种 相似文献
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研究了杨树菇菌丝体在不同培养基不同pH条件下液体培养的生长情况。试验结果表明 :磷酸二氢钾对杨树菇菌丝体生长有明显的促进作用 ,培养基含有磷酸二氢钾时的菌丝最高生长量要比不含磷酸二氢钾的最高生长量高出 0 12 2g/ 10 0mL ;磷酸二氢钾对培养基灭菌前后pH的变化有缓冲作用 ;培养过程中含有磷酸二氢钾的培养基pH变化较不含磷酸二氢钾的变化明显 ;杨树菇液体培养的适宜pH为 5 0~ 7 0 ,最适pH为 6 5 9~ 6 87。 相似文献
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以"蒙农4号"新麦草为试材,采用不同追肥时期(果后营养期、返青期、孕穗期,处理代号记为T1、T2、T3),不同追肥量(33.3、66.7、100.0、133.3、166.7g·m-2,处理代号记为N1、N2、N3、N4、N5)对"蒙农4号"新麦草进行田间试验,研究了磷酸二铵对"蒙农4号"新麦草种子产量及其构成因子的影响,以期为生产实践提供理论依据。结果表明:追施磷酸二铵可以明显提高6年生"蒙农4号"新麦草种子产量,以果后营养期追施166.7g·m-2的效果最佳,种子产量达到最大值为1 546.44kg·hm-2,比对照提高了355%。影响"蒙农4号"新麦草种子产量的主要因子是生殖枝数;小穗数、千粒质量、每小穗小花数和每小穗种子数对种子产量影响较弱。 相似文献
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R. B. Austin 《The Journal of Horticultural Science and Biotechnology》2013,88(4):277-285
Variations in final plant density (number of plants per square foot) lead to variations in yield in onion variety trials and often complicate the interpretation of the results. These variations in plant density may be caused by differences in germination and in seedling survival. Such differences were obtained from several lots of genetically similar seed of the onion variety Cambridge No. 10 which had been produced under different environmental conditions, viz. in different places and years. It was found, however, that variations in yield produced by these environmental effects on the seed could be allowed for within limits by using a statistical method based on the regression of final plant density on yield.Where seed of one stock of this variety was produced in each of three years by harvesting the seed heads at various stages of maturity and drying them at either 25° C. or 35° C., all except one lot of seed gave variations in yields of onions which were related to final plant densities. The exceptional lot, consisting of the least mature seed dried at 35° C., gave not only poor germination and seedling survival but also less vigorous surviving plants than those from the other lots. 相似文献
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为探明外源化学物质对红叶桃叶片着色的影响及其机制,以‘筑波5号’离体叶片为试材,研究不同浓度NaCl、蔗糖及KH_2PO_4处理对叶片中花色苷生物合成途经相关基因表达水平的影响。结果显示:低浓度NaCl(100和200 mmol′L~(-1))短时间(4 h)处理能提高花色苷合成结构基因CHI、UFGT和转录因子基因MYB10、bHLH33的表达水平;0.3%蔗糖处理8 h对UFGT、MYB10和bHLH33的表达促进作用显著;0.2%KH_2PO_4处理8 h对CHI、UFGT、MYB10、bHLH33和WD40的表达也具有显著的促进作用,而且CHI的表达在一定范围内随蔗糖及KH_2PO_4浓度增大和处理时间延长,效果更明显。除了0.2%KH_2PO_4处理8 h提高了WD40的转录外,NaCl、蔗糖及KH_2PO_4对MYB15和WD40的表达均具有显著抑制作用。 相似文献