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61.
Linaria maroccana Hook. f. Ann., ‘Lace Violet’, Lupinus hartwegii ssp. cruikshankii Lindl. ‘Sunrise’ and Papaver nudicaule L. ‘Meadow Pastels’ seeds were directly sown into 105 cell plug trays and received either ambient light or supplemental high intensity discharge (HID) lighting. For each species, a 2 × 3 × 3 factorial was used with two light intensities during propagation, three transplant stages, and three night temperatures. Seedlings were transplanted at the appearance of 2–3, 5–6, or 8–9 true leaves. Transplanted Linaria and Papaver seedlings were placed at 5/11, 10/16, or 15/21 ± 1 °C night/day temperatures and Lupinus seedlings were placed at 15/24, 18/25, or 20/26 ± 2 °C night/day temperatures. For this study, the optimum production temperature for Linaria was 10/16 °C as the cut stems produced at 15/21 °C were unmarketable and production time was excessively long at 5/11 °C. At 10/16 °C, Linaria seedlings should be transplanted at the 2–3 leaf stage to maximize stem number, stem length and profitability. For Lupinus the optimum temperature was 15/24 °C due to long stems and high profitability per plant. Lupinus seedlings should be transplanted at the 2–3 leaf stage when grown at 15/24 °C to obtain the longest and thickest stems; however, $/m2 week was higher for plants transplanted at the 8–9 leaf stage due to less time in finishing production space. For Papaver, the 15/21 °C temperature was optimal as that temperature produced the longest stems in the shortest duration, resulting in the highest $/m2 week. At 15/21 °C Papaver plants should be transplanted at the 2–3 leaf stage. Supplemental HID lighting had no effect on any of the species. 相似文献
62.
In a previous experiment it has been found that maximum uptake rate (Imax), Michaelis constant (Km), and minimum nutrient concentration (Cmin) as plant physiological characteristics may be important for phosphorus (P) uptake in peat-substrate. Thus, variation of P uptake parameters was evaluated with a series of depletion studies for poinsettia (Euphorbia pulcherrima) and marigold (Tagetes patula) under fluctuating climatic conditions and different developmental stages. 相似文献
63.
樱桃透光和郁闭树冠相对光照强度及其果实品质和产量的差异 总被引:6,自引:2,他引:4
以13年生‘红灯’甜樱桃(Prunus avium L.)为试材,应用树冠分格方法,研究了树冠透光和郁闭两种冠型内相对光照强度及其果实品质和产量的差异,以及相对光照强度与果实产量品质的关系。结果表明,两种树冠内相对光照强度均自下而上逐渐增高,透光和郁闭树冠小于30%的相对光照区域分别占树冠总体积的25.23%和52.78%。透光树冠果实分布均匀,主要集中在树冠1.5~2.5 m的高度;而郁闭树冠果实分布差异较大,主要在树冠的外围和上部;产量分别是9.02t.hm-2和3.53t.hm-2。果实品质因素与相对光照强度的回归分析表明樱桃单果质量、果实硬度、果实可溶性固形物含量、可滴定酸含量、固酸比最佳的相对光照强度值分别为76.52%、46.84%、100.00%、41.63%和75.77%。 相似文献
64.
柴油发动机广泛应用于各类农业机械中,由其带来的噪声污染也日益严重.为研究柴油机的整机噪声,利用声强测试技术中的p-p法,对某型农用六缸柴油发动机进行实测.通过对发动机各包络面上声强分布和声功率测试结果的分析,确定了其噪声源的位置、声功率的大小、主要噪声频率及整机辐射强度,为控制柴油发动机噪声污染提供了理论依据. 相似文献
65.
66.
温度、盐度和光照强度对鼠尾藻氮、磷吸收的影响 总被引:9,自引:0,他引:9
在实验室条件下,研究了不同的温度和盐度组合,温度和光照强度组合对鼠尾藻(Sargassum thunbergii)氮、磷吸收速率的影响.结果表明,上述3个环境因子对鼠尾藻氮、磷吸收速率均有显著影响.其中,温度和盐度对鼠尾藻氮、磷吸收速率有极显著影响(P<0.01),二者交互作用也极显著(P<0.01).在盐度20、温度25℃条件下和盐度30、温度30℃条件下,鼠尾藻对氮有较高吸收速率,分别为11.26μmol/[g(dw)·h]和11.01 μmol/[g(dw)·h];在盐度40、温度15~30℃范围内对磷的吸收速率较大,达到1.5μmol/[g(dw)·h]以上.温度和光照对鼠尾藻氮、磷吸收速率均有极显著影响(P<0.01),二者交互作用极显著(P<0.01).在温度15℃和光照强度140~180μE/(m2·s)以及温度20~25℃和光照强度60~100 μE/(m2·s)条件下,鼠尾藻对氮有较高吸收速率,均在9.60 μmol/[g(dw)·h]以上;在温度25℃和光照强度60μE(m2·s)条件下,鼠尾藻对磷的吸收速率达到最大,为1.30 μmol/[g(dw)·h].本研究结果表明,鼠尾藻总体上对水体中的氮、磷均具有较高的吸收速率,且能较好地同时吸收NH4+-N和NO3--N,显示了它对海水环境中营养盐具有较强的吸收能力. 相似文献
67.
Kenzo Yoseda Kazuhisa Yamamoto Kimio Asami Masayuki Chimura Koji Hashimoto Shinichi Kosaka 《Aquaculture (Amsterdam, Netherlands)》2008,279(1-4):55-62
This study investigated the effect of different light intensities on feeding, growth and survival of early stage leopard coral grouper Plectropomus leopardus larvae. Four different light intensities (0, 500, 1000 and 3000 lx) were used and larvae were kept under constant light conditions from 0 day after hatching (DAH) to 5 DAH. The larvae were fed a small S-type of Thai strain rotifers at a density of 20 individuals/mL from 2 DAH. The number of rotifers in larval digestive organ and total length of larvae were examined at 3 h intervals between 04:00 and 22:00 h on 3 DAH, and thereafter at 6 h intervals until the end of the experiment (5 DAH). Four experimental trials of the larval rearing were repeated using by 60 kL mass-scale rearing tanks. The results indicate that coral grouper larvae are visual feeders and their food intake increases with increasing light intensity. Food intake of larvae reared at 3000 lx was significantly higher than those reared at 0–1000 lx on 3 DAH despite being the first-feeding day (P < 0.01). On 4 DAH, total length of larvae reared at 3000 lx was significantly larger than those reared at the lower light intensities (0, 500 and 1000 lx), and thereafter light intensity significantly influenced larval feeding and growth until the end of the experiment. Survival on 5 DAH did not show a significant difference between light intensities, but survival rate at 3000 lx and 1000 lx had a tendency to be higher than those reared at the lower light intensities (0 and 500 lx). In contrast, larvae reared at 0 lx exhibited stagnant and/or negative growth. These results indicate that light intensity is significantly the factor affecting larval feeding, growth, and survival in coral grouper larvae under the rearing conditions. 相似文献
68.
韭菜迟眼蕈蚊紫外敏感视蛋白基因的克隆及光强度对其表达量影响 总被引:1,自引:0,他引:1
为明确韭菜迟眼蕈蚊Bradysia odoriphaga紫外敏感视蛋白基因Bo-uv的作用及其与趋光性的关系,利用常规PCR方法克隆获得Bo-uv基因的全长cDNA序列,分析了其敏感视蛋白的氨基酸序列与其它12种昆虫同源蛋白氨基酸序列之间的系统进化关系,运用qPCR技术检测了不同发育阶段、不同组织及不同光强度下Bo-uv基因的相对表达量。结果表明,Bo-uv基因cDNA全长2 757 bp,开放阅读框1 542 bp,编码514个氨基酸。韭菜迟眼蕈蚊紫外敏感视蛋白的氨基酸序列与其它12种昆虫同源蛋白的氨基酸序列一致性为21.93%~43.00%,与橘小实蝇Bactrocera dorsalis的氨基酸序列同源性最高。Bo-uv基因在韭菜迟眼蕈蚊蛹末期、成虫期表达,在成虫头部的相对表达量较高。在0~10 000 lx光强范围内雌、雄成虫体内该基因的相对表达量均呈先增高后降低趋势。与对照相比,1 000 lx光强度下其相对表达量显著升高,10 000 lx时相对表达量显著降低。表明光强度能够有效地调控Bo-uv基因的表达,该基因在韭菜迟眼蕈蚊感知外界光刺激过程中具有重要作用。 相似文献
69.
70.
以阔叶空心菜为试材,研究蕹菜芽苗菜对LED 光强和光质的生长响应。结果表明:绿化阶段结束时处理L7000RBW4∶1∶1(光强7 000 lx,红光∶蓝光∶白光为4∶1∶1)的脱壳率显著高于其他处理;光强为7 000 lx 时,3 种光质处理的蕹菜芽苗菜可食部分干质量均显著高于白光对照;光照强度过高显著影响叶绿素的累积,高光强(L11000)下的叶绿素a、叶绿素b 含量及叶绿素总量随红光比例的增加而降低,同时子叶白化现象越发明显;不同光强条件下,3 种光质处理的抗坏
血酸含量均随着红光比例的增加而降低,而可溶性糖含量处理间差异不显著;主成分分析结果表明,L7000RBW4∶1∶1 在本试验条件下表现最佳,是较适宜蕹菜芽苗菜工厂化生产的LED 光源配方。 相似文献