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1.
龙眼远程商业运输保鲜技术分析 总被引：2，自引：1，他引：2
目前龙眼运往欧美市场主要通过空运和海运两种方法,将其放在泡沫箱里,加入一定量的冰块,空运到欧美市场,不仅运费昂贵,而且质量也不能得到保证,而选择耐贮运品种,适时采收和适当的保鲜处理后进行冷柜运输,不仅运费低,而且能保持较好的品质,是选择打进欧美市场的最佳运输方法。 相似文献
2.
试验根据2002年和2003年两年在黑龙江省各市县地区所采集的大豆花叶病毒病(SMV)样品所表现的症状,利用MVSP3.1.2版本的软件分别对其进行聚类分析,研究大豆花叶病毒在黑龙江省各市县地区的症状表现规律以及分布规律。 聚类结果表明：黑龙江省的各地区SMV表现的主要症状为皱缩型,其次为黄化型的,只有极少数表现为畸形。在2003年的223份样品中有一半的样品表现为皱缩;在2002年的126份样品中有80％的样品表现为皱缩。这些说明黑龙江省的大豆花叶病毒主要以１号株系为主。 为进一步研究黑龙江省各地区的发病情况,将黑龙江省划分为东、西、南、北四大块。分别对各部分的病毒样品的症状进行聚类分析,结果表明：各地区也基本以皱缩型SMV为主,大致规律与黑龙江省的整体发病规律相吻合。 相似文献
3.
Summary The resistance of 19 cultivars of subterranean clover was screened against 4 races of P. clandestina by mycelial inoculation of roots of 10-day-old seedlings growing in water agar and by growing seedlings in pasteurised potting mix containing infested vermiculite in controlled conditions. The cultivars showed differential resistance (vertical resistance) to races of the pathogen and can be divided into 4 resistance groups. Cultivars Clare, Esperance, Green Range, Junee, Mount Barker, Rosedale, Woogenellup and Yarloop were susceptible to all races. Cultivars Bacchus Marsh, Denmark, Enfield, Gosse, Goulburn, Karridale, Larisa, Leura and Trikkala were susceptible to races 1 and 3, but resistant to races 0 and 2. Cultivar Meteora was susceptible to races 2 and 3, but resistant to races 0 and 1. Cultivar Seaton Park (LF) was resistant to all races. Cultivars also varied in their race-non-specific (horizontal) resistance: cultivars that were susceptible to particular races usually varied in their degree of susceptibility to those races. In particular, Junee was more resistant to all four races than the other cultivars within its group. Similarly, cultivars Gosse, Larisa, Denmark and Trikkala were more resistant to races 1 and 3 than the other cultivars in their group. Races of the pathogen varied in their aggressiveness as well as in their virulence, as shown by the variation in aggressiveness of different isolates of race 0. 相似文献
4.
扁豆在中国广泛栽培,紫色扁豆品种的豆荚中的花青素含量高于绿色品种,但扁豆中花青素合成的调控机制尚待研究。鉴于扁豆基因组测序工作尚未完成,为了解析扁豆花青素合成的调控机制,本研究利用Illumina转录组测序技术,获得了假定Unigene 94982个。与紫色扁豆相比,绿色品种的荚皮中上调Unigene1065个,下调3086个。通过GO、KEGG基因富集分析以及20个表达差异最大的Unigene功能预测,可以发现,绿色扁豆品种抗锈病能力较强,可能与抗氧化能力、氧化还原反应、40S核糖体小亚基(与翻译有关)蛋白高于紫色品种有关,而扁豆豆荚颜色由紫变绿的原因与生长素类AUX蛋白、类衰老特定的半胱氨酸蛋白酶等编码基因的表达水平下调有关。本研究将为解析扁豆花青素合成的调控机制提供借鉴。 相似文献
5.
An experiment in which two different intensities of selection were applied, in each of three successive generations, to two varieties of Brussels sprout showed that the progeny resulting from lax selection were frequently inferior in agronomic characteristics to those from the more stringent selection. In one of the varieties used, this inferiority took the form of an increase in the proportion of off-types, and in the other there was a decrease in yield.These results imply that deterioration in the agronomic value of a variety is likely to occur whenever standards of selection are relaxed, for example, to accelerate the multiplication of seed. It is suggested that such deterioration is most likely to occur in those characteristics for which selection has improved the uniformity of a variety but has produced only partial homozygosity over the range of loci affecting those characteristics. 相似文献
6.
北京延庆甘蓝枯萎病发生和危害调查 总被引：7，自引：2，他引：5
【研究目的】对北京市延庆县2002—2006年期间甘蓝枯萎病的田间发生和危害进行了追踪和实地调查,旨在为后续研究和病害综合控制实践提供参考。【方法】文献追溯法、田间实地调查、数据分析方法;【结果】近五年来甘蓝枯萎病在北京市延庆县的发生呈现快速上升趋势,由2002年的2个村约13.3 hm2发展到2006年的25个村86.7hm2,提高了6.5倍。病害造成的产量损失高达30%以上,甚至绝收。甘蓝枯萎病的发生和危害与田间土壤、气候和品种抗病性关系密切;生产中目前尚无有效的预防控制措施。系统研究病原种类、初侵染来源和病害传播方式具有紧迫性。【结论】加速甘蓝种子健康检测和杀菌剂预防保健处理、筛选适合与土壤消毒的化学药进行应急防治的配套技术措施研究是病害综合防治的重点。 相似文献
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Summary Nine polyploids (including two mixaploids) were obtained in Trifolium riograndense with three methods of colchicine application to seedlings: immersion, dropping and cotton. The best method showed to be immersion for 6 h in 0.30% colchicine. Leaves with more than 3 folioles were frequently observed in some (but not all) polyploids. The number of pollen grain pores increased from 3 to 4 in tetraploids. Stomatal cell size was not a reliable criterium to distinguish ploidy levels. Two percent of aneuploidy occurred in the C1 generation. Meiotic behavior was characterized by high bivalent and low quadrivalent numbers with suggestions of genetic control of chromosome pairing. Meiotic index ranged from 70% to 98% and pollen viability from 66 to 90%. An apparent tendency to decrease the number of quadrivalents and to increase mean meiotic index and pollen viability from C0 to C1 was detected. The use of these autopolyploids in basic and applied research as well as in genetic breeding is promising. 相似文献
8.
沈阳市霜期农业气候资源特征分析 总被引：3，自引：2，他引：1
研究霜期农业气候资源变化,为沈阳市霜期农业顺利发展,趋利避害提供科学依据。利用沈阳1951-2010年气象资料,采用常规数理统计方法,分析霜期光热水资源变化特征。结果表明：近60年来,因气候变暖沈阳市霜期缩短趋势明显,气象要素变化稳定性较差。与1951-2010年相比,近30年的霜期气温升高0.9℃,高温年增加5.7%;日照时间减少66 h,寡照年增加16.7%;降水量增加8.3 mm,多雨雪年增加5%;阴天日数增加6天,几率提高8.3%;大风日数减少,大、暴雪次数变化平缓。连续阴天寡照、气温升高变化不稳是沈阳市冬季气候特点,对冬季设施农业发展影响较大。只有完善设施农业设备现代化、智能化功能,才能更好地发挥光热资源效率。 相似文献
9.
Ricardo Augusto Diniz Cabral Ferreira Magno Antonio Patto Ramalho Fernando Henrique Ribeiro Barrozo Toledo Angela de Fátima Barbosa Abreu 《Plant Breeding》2015,134(5):599-604
In the common bean crop in Brazil, the requirement of the value for cultivation and use trials is that these experiments must be conducted over two years in three locations per region. Information in regard to the necessary number of years to ensure precision in cultivar recommendation and the influence of evaluated years in the estimation of the GE interaction are still scarce. Using grain yield of five check varieties assessed over 11 years in three sowing seasons per year, the aims of this study are as follows: to measure the relative contribution of the GE interaction, evaluating the implication of the number of years in the estimates of the GE interaction, and infer how many years are needed to ensure precision in cultivar recommendation. For instances, analysis of variance was carried out involving all environments and also combinations of years. The results showed that the GE interaction was greater than all other cross‐effects involving lines. The use of at least two years allows good coincidence in cultivar recommendation compared to the whole period. Increasing the evaluation time is a good strategy, especially when it is difficult to grow three different sowing seasons. 相似文献
10.
为探索安康烟区烤烟物理性状年度间变化规律,对安康烟区2011－2016年不同部位的烤烟物理性状指标进行分析。结果表明,烟叶物理性状在年度间存在差异,下部叶2014-2015年含梗率有所上升,2016年下降;除2013和2016年外,中部叶含梗率较高;上部烟叶2011-2013年含梗率逐年下降,此后至2015年逐年升高,2016年再次下降。下部烟叶单叶重年度间变化不大,2016年中部烟叶单叶重显著升高,上部烟叶单叶重以2011和2016年最高。下部烟叶叶面密度逐年缓慢升高;中部烟叶叶面密度2011-2013年逐年升高,此后至2015年缓慢下降,2016再次升高;上部烟叶叶面密度2011-2012年逐年升高,此后至2015年逐年下降,2016年再次升高。下部烟叶开片度年度间变化不大,中部烟叶开片度2011-2014年总体表现出逐年下降的趋势,此后至2016年逐年快速升高;上部烟叶开片度2011-2014年逐年下降,2015年有所回升,2016年再次下降。中下部烟叶拉力在2011-2012年无明显变化,2013年有所下降,此后至2015年无明显变化,2016年迅速升高;上部烟叶拉力2011-2012年无明显变化,2013年下降,此后至2015年逐年上升,此后至2016年无明显变化。 相似文献
11.
The origin of sorghum hybrids developed in China in the past several decades was analyzed in order to assess genetic contribution
of Chinese landraces (Kaoliang) to the sorghum hybrids, to evaluate the genetic diversity existing in the A-lines and R-lines
mainly used in breeding programs, and to outline a proper strategy for the future development of sorghum improvement. Basically,
Chinese sorghum landraces have played an important role in the development of R-lines while foreign germplasm have played
an essential role in the development of A-lines. Because cytoplasmic male-sterility has not been certainly found in Chinese
sorghum, cytoplasmic and nuclear genetic backgrounds of A-lines will continue to depend on foreign sorghum types in the future.
Genetic diversification including cytoplasmic diversification has to be a priority in future hybrid breeding and production.
To obtain superior hybrid vigor, Chinese sorghum germplasm will have to play a more important role in hybrid breeding programs
in the future.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
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13.
Automobile comfort dynamic simulation is necessary when we predict and evaluate the comfort of a automobile or optimize performance of automobile. The nine DOF vibration model of automobile is established , which acts root mean square value of body in multiple work conditions as comfort evaluation indices. Based on the comfort simulation, the Hongyan 1160 is predicted in the way of comfort. The programmes can be used in many different automobiles . The computational result indicates that the model can simulate vibration of automobile truly. It is significant to research automobile comfort evaluation to optimize performance of automobile and comfort simulation .The computational program can be applied to optimize or simulate which has some reference value. 相似文献
14.
中国东北地区春雨开始期变化特征研究 总被引：3，自引：1，他引：2
为了研究中国东北地区春雨开始期的变化特征,揭示影响其变化的主要因素及影响机理,利用近50年（1959-2008年）东北地区（包括黑龙江、吉林、辽宁和内蒙古东北部）地面测站降水资料,给出了东北地区春雨开始期的划分标准及其推进特征,并分析了东北地区春雨开始期的时空分布特征。结果表明,东北地区春雨平均在5月下旬开始,由东南向西北推进。当东北地区春雨开始偏早（晚）时,东北地区5月的降水偏多（少）;主要以全区一致型,南北反相型和东南向西北“-+-”的空间分布特征;东北地区春雨开始期具有显著的年际变化,存在准2~3年的年际振荡特征。此外,当前期12-4月中国东部沿海海温偏高（低）时,东北地区春雨开始期偏早（晚）。 相似文献
15.
为更好地推进西藏自治区昌都市芒康县盐井乡葡萄产业长足发展，本研究采取平行观测、数理统计的方法开展盐井葡萄物候期人工观测和所在区域气象要素自动监测，根据所得数据分析葡萄生长的不同阶段对气候条件的适应性，并提出灾害防御对策。结果表明，盐井葡萄一般在3月上旬—下旬开始萌芽，5月上中旬进入开花期，6月下旬—7月上旬进入浆果膨大期，1个多月后葡萄开始转色，10月中旬进入成熟期，10月下旬开始落叶随即进入休眠期。从萌芽到成熟，盐井葡萄约需200天左右。盐井光照条件完全能满足葡萄的正常生长和发育的需要，在芽萌动期间逐日气温大都高于10℃，在开花期日平均气温为16.4～20.6℃，且80%以上的时间大于25℃。浆果膨大期日最高气温平均为21.9～28.0℃，期间风力大，20多天风速都达到10 m/s。从萌芽到坐果期，降水很少，从浆果膨大期开始雨水不断增多，但依旧不能满足葡萄生长发育，必须通过灌溉才能满足。 相似文献
16.
在福建省沙县稻瘟病重发区,对1092份水稻材料进行连续3年的田间苗叶瘟和穗茎瘟的自然鉴定,供试材料中高抗、抗、中抗、中感、感和高感材料分别为124、99、121、545、156和47份。利用14个与抗性基因紧密连锁的SSR标记及3个源于抗病基因序列的显性标记,对其中130份抗性较好的材料进行了遗传背景分析,14个SSR标记引物共扩增到87个等位位点,每一标记的等位位点变幅为2～13个,平均为6.2个,每个SSR位点的多态性信息含量(PIC)变化范围为0.379～0.9,平均为0.695;不同抗性亲本材料出现抗性基因的标记为2～9个,其中与抗病基因Pi35、Pi-yt及Pi-ta相对应的标记RM1003、RM202和YL155/YL87的概率较高。 相似文献
17.
日光温室外保温系统设计及其对温室进光量的影响 总被引：1，自引：0，他引：1
为改进日光温室的性能,对日光温室保温被的存放方式进行改装。日光温室保温被的改装主要在后坡焊接存放架,用来存放保温被,存放架具的角度为16.7°,便于保温被的下放。这样做一方面提高了白天保温被的卷起高度约40 cm,也有可能增强冬季温室中的光照强度;另一方面提高了棚顶的通风口高度约20 cm,有可能增强温室中的通风能力。同时,在夏季可以把保温被存放在存放架上,这样可以节省人力,也减少保温被的磨损,延长了保温被的使用年限,在实验所用日光温室的使用年限内可以节省18000元左右,并且节省存放保温被的空间。但是该设计也存在不足,即保温被存放在棚顶后,增加了日光温室的脊高,冬季时增加温室背面的阴影长度89 cm,可能影响到后面温室的采光。本实验通过对温室中光及通气性能的测定、财力物力节省状况的研究,考察该设计的可行性,并对改进后存在的缺点提出解决方案。 相似文献
18.
论脯氨酸累积与植物抗渗透胁迫 总被引：7，自引：3，他引：7
脯氨酸是植物体内适应逆境胁迫的一种重要的渗透调节物质。此文概述了脯氨酸在植物抗渗透胁迫中的作用、累积机制以及植物编码脯氨酸代谢、运输相关的酶基因和抗渗透胁迫基因工程改良等方面的研究进展,分析提出了目前植物抗渗透胁迫研究方面存在的问题,并对今后研究的重点进行了展望,以期为植物抗逆性的遗传改良提供理论依据。 相似文献
19.