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991.
十个外引啤酒大麦品种产量及品质分析 总被引:1,自引:0,他引:1
为筛选适合甘肃河西地区种植的优质啤酒大麦品种,在甘肃民乐、张掖、山丹、黄羊镇、永昌5个试验点进行两个生长季的品比试验,对10个外引啤酒大麦品种和当地主栽品种的生育期、产量及主要品质性状进行了比较。结果表明,与当地主栽品种甘啤4号相比,10个引进品种生育期相对偏长,有8个品种比对照晚熟;品种Beatrix和Belana表现增产,两年多点试验平均产量分别较对照甘啤4号增产13.31%和8.45%。10个外引啤酒大麦品种的千粒重、发芽势、发芽率达国标一级标准;麦芽品质指标α-氨基氮和糖化力达国标优级标准,浸出物除品种Marnie外均达国标一级标准,库尔巴哈值除品种Xanadu外均达国标一级标准。经产量与品质综合分析,外引啤酒大麦品种Beatrix和Belana在甘肃河西走廊及沿黄灌区气候及土壤条件下表现优良,适宜推广种植。 相似文献
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ZHOU Juan SHU Xiaowei LAI Shangkun XU Gaoping HUANG Jianye YAO Youli Yang Lianxin DONG Guichun WANG Yulong 《中国水稻科学》1986,34(6):561-573
【Objective】Our aim is to investigate the differences in response of grain yield, nitrogen absorption and utilization to FACE (atmospheric CO2 concentration increase) of different rice varieties. 【Method】Six rice varieties, including conventional japonica rice, hybrid indica rice, and conventional indica rice, were used to study the effects of free-air CO2 enrichment (FACE) (atmospheric CO2 concentration increase) on the nitrogen absorption, utilization, and yield of different types of rice.【Result】 1) FACE treatment dramatically increased rice yield by 24.17% on average and the maximum increment was observed in conventional indica rice. Compared with other types of rice varieties, hybrid indica showed the highest grain yield under both FACE and control (CK) treatments. 2) Panicle number was significantly improved in FACE treatment with conventional japonica rice varieties having the maximum increment. Spikelet number per panicle was significantly improved in hybrid and conventional indica rice varieties in FACE treatment. 3) The nitrogen absorption (NA) and nitrogen use efficiency for grain yield (NUEg) were significantly higher in FACE treatment than those in CK treatment. The average increase of NA was 21.23% with the maximum increment in hybrid indica rice varieties. Compared with other rice varieties, conventional indica rice varieties had the highest NA both in FACE and CK treatments. The average increase of NUEg was 7.33% with hybrid indica rice varieties enjoying the maximum increment. The hybrid indica rice varieties had the highest NUEg in FACE treatment and in CK treatment, respectively. 4) Nitrogen content was decreased in FACE treatment with the average decrease of 0.105%, among which the maximum decrease was observed in conventional japonica rice. Dry matter weight was extremely and significantly increased in FACE treatment. The average increase of dry weight was 23.95% with the maximum increment in conventional indica rice varieties. NA of single panicle was significantly improved in FACE treatment with the average increase of 10.79% in conventional indica rice varieties and 13.93% in hybrid indica rice varieties, but NA of single panicle was decrease by 9.60% in conventional japonica rice. FACE treatment significantly increased rice NA intensity with an average increase of 22.29% and the maximum increment was observed in hybrid indica rice varieties. The growth duration was not influenced by FACE treatment in all rice varieties. NAs of stem, leaf and panicle were significantly higher in FACE treatment than in CK treatment with the highest increase of 51.86% in leaf. The largest increase of NA was observed in hybrid indica rice. NA in different rice growth stages was significantly improved with the maximum increment of 108.90% during heading-maturity. The maximum increment of NA from heading to maturity was observed in hybrid indica rice varieties.5) Effects of dry matter weight, NA per panicle, NA intensity, NA of panicle and NA from heading to maturity on NA at maturity were greater than those of nitrogen content, panicle number, growth duration, NAA of leaf, stem and sheath, NAA during transplanting-tillering and tillering-heading. 6) Partial productivity of nitrogen fertilizer (PFPN) was significantly improved in FACE treatment with an average increase of 24.16% and the maximum increment in conventional indica rice. NAA per 100 kg grains was significantly reduced in FACE treatment with an average decrease of 4.7%. The maximum decrease of NAA per 100 kg grains was observed in conventional indica rice varieties.【Conclusion】The results indicated that FACE could markedly increased both grain yield and nitrogen use efficiency in all rice varieties, but the increases varied with the variety types. 相似文献
995.
饲料氨基酸对褐飞虱及其蜜露游离氨基酸的影响 总被引:2,自引:0,他引:2
利用氨基酸组成不同的全纯人工饲料对褐飞虱(Nilaparvata lugens)成虫进行饲养,研究了饲料氨基酸对该虫及其蜜露中游离氨基酸的影响。结果表明:1)饲料对试虫体内游离氨基酸有明显影响。在不能摄入任何氨基酸的试虫体内,游离氨基酸总量降至可以获得全部氨基酸的试虫的63.2%,其中缬氨酸、苏氨酸、异亮氨酸、亮氨酸、赖氨酸和半胱氨酸下降明显,但蛋氨酸增多。在仅能摄取到非必需氨基酸的试虫体内,蛋氨酸、赖氨酸和亮氨酸的含量与不能摄取到任何氨基酸的试虫处在同一水平,甚至明显低于后者;苏氨酸和组氨酸则明显高于可以获得全部氨基酸的试虫,异亮氨酸、苯丙氨酸和精氨酸亦达到了后种试虫的含量水平,缬氨酸的含量虽然低于后者,但与仅能摄取到必需氨基酸的试虫处在同一水平。2)蜜露中的游离氨基酸组成基本与饲料内的相一致,但相对含量有较大差别,而且少数不存在于饲料中的氨基酸可以在蜜露中检测到。文中对必需氨基酸的补偿代谢进行了讨论,初步认为褐飞虱体内至少可以合成苏氨酸、组氨酸、异亮氨酸、苯丙氨酸、精氨酸和缬氨酸等6种必需氨基酸。 相似文献
996.
来进花 《甘肃农业大学学报》2002,37(2):260-264
对在校1~4年级本科生采用“国际防痨和呼吸病联盟烟草与健康委员会”设计的调查表为基础,根据甘肃农业大学的生源实际情况,自行设计自填式问题调查表进行调查,共调查565人,对553份有效答卷进行统计分析。结果表明:大学生总吸烟率为63.8 %,其中每日吸烟者占18.8 %,偶尔吸烟者占45.0 %;烟卷种类有普通型和过滤嘴型,其中以过滤嘴烟卷为主,占74.2 %;每日吸烟10支以上占53.8 %;大学生对控制全社会吸烟的态度较积极。不吸烟的原因,60.6 % 的学生认为是“保护自己的身体健康”;30.4 % 的学生是“为了不使周围人感到讨厌”;34.5 % 的学生不吸烟是为了“省钱”。大学生对吸烟危害认识不清,不吸烟并不是源于自身健康的要求,而是屈从于外界条件,控制大学生吸烟需要全社会与学校的密切配合。 相似文献
997.
区域森林景观破碎化对比分析 总被引:4,自引:0,他引:4
以盆地丘陵区(仁寿县和营山县)和川西地区(道孚县)典型区域的林相图和调查资料为基础,结合林分起源和林种分析,研究了森林景观破碎化特征,针对不同区域景观破碎化的现状,提出了不同区域森林经营的具体措施。结果表明,不同区域林业用地类型的破碎化和主要植被的破碎化差异均显著;由于人为活动干扰,森林破碎化总体上表现为盆中和盆周地区显著高于川西地区;对人类活动的合理调控与管理有利于森林景观恢复与景观安全格局的维持。 相似文献
998.
采用固态发酵工艺与酶活性测定法研究发酵菌种、原料组成及原料灭菌处理对马铃薯渣发酵饲料中与动物饲料消化率密切相关的4种重要水解酶活性的影响。结果表明:向马铃薯渣中接入酵母菌(Yeast)、黑曲霉A8(Aspergillus niger A8)及米曲霉(Aspergillus oryzae)发酵剂能大幅度提高发酵产物蛋白酶、纤维素酶、果胶酶及植酸酶活性。加入尿素及油渣,进行原料灭菌处理也有类似效果:①发酵产物蛋白酶活性为184.20~564.90 U,发酵增率为191.7%~794.5%,接菌增率为68.9%~206.7%,灭菌增率为9.4%~45.2%;②纤维素酶活性为3 455.56~5 978.15 U,发酵增率为4.7%~81.1%,接菌增率为36.7%~73.0%,灭菌增率为1.7%~61.0%;③果胶酶活性为248.76~613.74U,发酵增率为19.5%~194.8%,接菌增率为10.2%~146.7%,灭菌增率为7.5%~71.1%;④植酸酶活性为23.63~107.08 U,发酵增率为67.7%~949.6%,接菌增率为109.4%~526.0%。除酵母菌接种的植酸酶外,其余4种水解酶接菌与不接菌的差异均达到显著水平(P0.05)。单接米曲霉处理发酵产物的蛋白酶活性明显高于其他处理;单接黑曲霉及黑曲霉与酵母菌混接处理发酵产物的植酸酶活性均高于其他处理。 相似文献
999.
在随机需求环境下,电信企业的价格策略表现为一个随时变化的调整轨迹,将寡头电信企业之间的价格竞争博弈刻画为微分博弈模型,并对模型进行了数值模拟和仿真分析,结果表明:在随机需求下,寡头电信企业的价格策略存在唯一的鞍点均衡路径,否则很难实现均衡状态;虽然寡头电信企业的价格处在动态调整中,但市场份额会相对稳定维持在某一均衡状态下。 相似文献
1000.