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991.
In order to analyze the effect of different temperatures on PAOs decay, a lab scale EBPR culture with PAOs over 90%±2% of the entire bacterial was used under different conditions (10℃ anaerobic, 10℃ aerobic, 20℃ anaerobic, 20℃ aerobic). The results show that the decay rate increases with the increase of temperature; the average rate during 1~9 days is (respectively: 10℃ anaerobic, 10℃ aerobic, 20℃ anaerobic, 20℃ aerobic) 0.053/d, 0.50/d, 0.072/d, and 0.145/d; the cell death rate is 0.019/d, 0.017/d, 0.019/d, and 0.03/d, which accounts for 35.8%, 34%, 26.4%, and 20.7% of the decay rate, respectively. The concentration of PHA and glycogen decreases during the decay period. And Glycogen degrades quickly in anaerobic conditions than in aerobic conditions under the same temperature. The glycogen degrade rate is higher with the increase of temperature under the same anaerobic and aerobic conditions. 相似文献
992.
Huimin Wang Xiaoming Xu Xiaodeng Zhan Rongrong Zhai Weiming Wu Xihong Shen Gaoxing Dai Liyong Cao Shihua Cheng 《Breeding Science》2013,63(3):267-274
Root system development is an important target for improving yield in rice. Active roots that can take up nutrients more efficiently are essential for improving grain yield. In this study, we performed quantitative trait locus (QTL) analyses using 215 recombinant inbred lines derived from a cross between Xieqingzao B (XB), a maintainer line with short roots and R9308, a restorer line with long roots. Only a QTLs associated with root length were mapped on chromosomes 7. The QTL, named qRL7, was located between markers RM3859 and RM214 on chromosome 7 and explained 18.14–18.36% of the total phenotypic variance evaluated across two years. Fine mapping of qRL7 using eight BC3F3 recombinant lines mapped the QTL to between markers InDel11 and InDel17, which delimit a 657.35 kb interval in the reference cultivar Nipponbare. To determine the genotype classes for the target QTL in these BC3F3 recombinants, the root lengths of their BC3F4 progeny were investigated, and the result showed that qRL7 plays a crucial role in root length. The results of this study will increase our understanding of the genetic factors controlling root architecture, which will help rice breeders to breed varieties with deep, strong and vigorous root systems. 相似文献
993.
结球甘蓝霜霉病是由十字花科寄生霜霉菌引发的严重病害。本研究利用高代自交系‘R103’抗病亲本和‘S101’感病亲本及其F2分离群体,于霜霉病病发高峰期田间自然诱发抗性鉴定,由单基因显性控制。运用AFLP分子标记技术,结合BSA法,对双亲和2对抗、感基因池的筛选和验证,获得2个与结球甘蓝抗霜霉病基因相关的AFLP标记。204 bp BoRAAC/CAC标记转化为SCAR标记,发现在抗病亲本和抗病池中与感病亲本和感病池中条带只存在量上的差异,在抗性选择起中只能起辅助作用;191 bp BoRAAG/CTC标记(EU-635443.1),转化为SCAR标记,仅在抗病亲本和2个抗病池中获得目的条带,经F2群体单株验证后,与抗性位点的遗传距离为5.7cM。利用BoRAAG/CTC113标记对F1和BC1群体与多年苗期霜霉病抗性鉴定的20份结球甘蓝种质资源进行验证和筛选,该标记与品种(系)的霜霉病抗性吻合率达到95%,初步表明该标记可应用于早期结球甘蓝抗霜霉病抗性辅助选择。 相似文献
994.
嫩江沙地樟子松人工固沙林天然更新特征 总被引:1,自引:0,他引:1
在调查分析的基础上,探索了樟子松天然更新苗龄分布、苗高分布、更新苗密度及更新分区规律,研究结果表明,33年生以上的樟子松人工林更新幼苗(树)苗龄主要分布在1~10年;樟子松天然更新幼苗5年生以前生长较缓慢,6年生开始加快生长。在樟子松林墙外缘5~23m范围内,樟子松更新幼苗(树)密度每10m2为10~72株,并且生长较好;林窗更新每10m2为45~350株。在距樟子松母树9~34m杨树林内,樟子松更新稠密,小黑杨林内每10m2达27株,银中杨林内每10m2达到19株。在杨树林内樟子松更新密集区幼苗(树)密度每10m2为11~14株,稀疏区更新幼苗(树)密度每10m2为4~7株。银中杨、小黑杨林内樟子松更新苗密集区最远边界分别达58m、71m,稀疏区最远边界分别为99m、110m。 相似文献
995.
996.
Huawei Su Yachun Wang Qian Zhang Fuwei Wang Zhijun Cao Muhammad Aziz Ur Rahman Binghai Cao Shengli Li 《Tropical animal health and production》2013,45(7):1495-1503
Twenty multiparous Chinese Holstein dairy cows calving in hot summer (S group), were compared with 20 similar control cows calving in cool autumn (C group). Diets were the same for both groups; prepartum diets had relatively low energy density. Average temperature–humidity index was 76.5 and 53.0 in summer and autumn, respectively. S group cows had significantly higher rectal temperatures (39.6 vs. 39.0 °C) and respiration rates (79.0 vs. 31.3 breaths/min) than C group, and consumed less feed (prepartum 8.0 vs. 12.3 kg/day, postpartum 16.3 vs. 21.2 kg/day). Calculated energy balance (EB) was ?7.98 vs. ?5.15 Mcal/day for S group prepartum and postpartum, respectively. In contrast, EB was 1.36 vs. ?2.03 Mcal/day for C group prepartum and postpartum, respectively. S group produced significantly less milk than C group by 15.4 % (5.2 kg/day) and 26.8 % (10.2 kg/d) for milk yield and energy-corrected milk, respectively. Percentages of milk fat (3.28 vs. 4.29 %), protein (3.08 vs. 3.33 %), and solids-not-fat (8.46 vs. 8.78 %) were significantly lower for S group. Milk urea nitrogen (19.54 vs. 13.31 mg/dL) was significantly higher in S group. Significantly lower feed efficiency was observed in S group (1.56 vs. 1.66). During the entire transition period, S group had significantly lower circulating glucose levels. S group had significantly higher levels of nonesterified fatty acids (NEFA) prepartum, but after 14 days in milk, NEFA was significantly lower. We conclude that increasing dietary energy density during transition period (especially prepartum) is necessary to minimize adverse effects of hot season. 相似文献
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1000.
本文汇集了我国近年来新发布的关于汽车运用工程国家或行业标准,对这些标准进行了特点分析和应用研究。 相似文献