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1.
导入AGPase基因的转基因可育水稻及其经济性状的研究   总被引:8,自引:0,他引:8  
以农杆菌介导法将淀粉合成关键酶AGPase(腺嘌呤二磷酸葡萄糖焦磷酸化酶)基因导入云南地方优质水稻合系35,38,39,41,42中,获得了大量的可育转基因植株。PCR扩增检测,外源基因已稳定整合进水稻基因组中。大量的农艺性状及淀粉含量研究表明,转基因水稻种子的千粒重比对照明显提高,但总淀粉含量没有显著变化。  相似文献   
2.
A laboratory evaluation was performed to evaluate the performance characteristics of a new veterinary ventilator. The ventilator studied was configured according to manufacturer's directions and attached to a test lung via a pneumotachograph and differential pressure transducer interfaced to a pulmonary mechanics analyzer system. Constant resistance (R=10 cm H2O/L/sec) and compliance (C=3 ml/cm H2O) factors were maintained for all trials. The ventilator operated at the manufacturer's preprogrammed parameters. In the first trial, body weight was the only variable. In the second trial, an endotracheal tube was placed in series between the ventilator's breathing circuit and the pneumotachograph. Body weights from 1–20 kgs were evaluated. Mean values for respiratory rate (RR), minute ventilation (VE), inspiratory time (Ti), peak inspiratory pressure (PIP), and peak inspiratory flow (Fpki) displayed on the ventilator control panel; tidal volume (VT), calculated from the displayed minute volume, and identical parameters measured by the pulmonary mechanics system at each body weight, were compared using a two factor analysis of variance. Significant differences (P< 0.05) were found between mean displayed and measured values for RR, PIP, and Fpki.  相似文献   
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通过对195份冬小麦资源品种(系)的抽穗期、灌浆时间与千粒重的试验分析表明,冀东冬小麦的抽穗期主要在5月1日~5月14日之间,而5月7~5月13日是抽穗的高峰期,达到总量的80.4%;灌浆时间在35~45d之间,以37~41d的品种最多,占品种总数的88.2%.随抽穗期的推迟、灌浆期的缩短,千粒重呈显著下降趋势,相关系数分别为 r=-0.4365和r=0.8924.  相似文献   
5.
Five physiological and eleven yield traits of two pairs of sister lines generated from a high generation with similar genetic background (SLs) for purple pericarp were investigated to explore the reasons behind low-yield production of colored rice. Of the five physiological traits examined, except grain anthocyanin content, there were generally similar trends between the P (purple-pericarp) lines and the corresponding W (white-pericarp) lines over two seasons (in the year 2009 and 2010 separately). The results demonstrated that the chlorophyll content of flag leaves, the net photosynthetic rate of flag leaves, and the grain anthocyanin content could be easily influenced by the environment. The physiological functions of the traits for the P lines were more active than those of the corresponding W lines in the year 2010. The grain anthocyanin content of the P lines was much greater in the year 2010 than in the year 2009 during the growth period. The investigation of yield traits revealed that the P lines had reduced 1000-grain weight, yield per plot and grain/brown rice thickness compared to the W lines. A difference comparison of these traits and a source-sink and transportation relationship analysis for these SLs suggested that small sink size was a key reason behind yield reduction of purple pericarp rice.  相似文献   
6.
At concentrations near 2 × 10?4M, barban, chlorpropham, and phenmedipham are inhibitors of the electron transfer in potato and mung bean mitochondria. The inhibition seems to be localized in the flavoprotein region. It affects preferentially the exogenous NADH dehydrogenation, in potato mitochondria (I50, 10?4M). Succinate dehydrogenation is less inhibited. At noninhibiting concentrations, the studied carbamates cannot uncouple the oxidative phosphorylations. Photosynthesis is completely inhibited by 2.10?7M phenmedipham, 5 × 10?5M barban, and 2 × 10?4M chlorpropham. The inhibition takes place at the PS II level. Moreover, barban and chlorpropham are uncouplers of the photophosphorylations for concentrations between 5 × 10?5 and 5 × 10?4M. The effects observed on mitochondrial respiration can also be found on respiration of Acer cultured cells. The effects on isolated chloroplast photosynthesis are also observed for slightly higher concentrations on cultured Chlorella and on pea and oat leaf fragments.  相似文献   
7.
干热风对冬小麦灌浆速率和千粒重的影响   总被引:9,自引:0,他引:9  
为定量分析冬小麦灌浆不同时期出现的干热风对小麦产量形成带来的危害,利用郑州农业气象试验站连续两个年度的干热风人工控制试验数据,结合前期作物观测资料,研究了干热风对冬小麦籽粒灌浆速率及千粒重的影响。结果表明,干热风导致冬小麦灌浆速率不同程度下降,不同时期干热风的降幅表现为灌浆中期灌浆后期灌浆前期,重度干热风轻度干热风。随着干热风后冬小麦的自身修复和后续灌浆进程,最终千粒重不同程度降低,降低幅度最大的是灌浆后期重度干热风,千粒重降低5.4g,降幅达14.5%;其次为灌浆中期重度和轻度干热风,千粒重分别降低9.7%和4.8%;再次为灌浆后期轻度干热风;而灌浆前期干热风对千粒重影响不显著。  相似文献   
8.
In order to clarify the impact posed by wheat powdery mildew (Blumeria graminis f. sp. tritici) on the yield and yield components in different epidemic seasons, field trials were conducted in three growing seasons, 2009-2010, 2010-2011 and 2011-2012, in Langfang City, Hebei Province, China. The relationships between 1000-kernel weight, crude protein content of grain and yield and disease index (DI), as well as area under disease progress curve (AUDPC) were studied. The models of the percentage of loss of 1000-kernel weight, crude protein content and yield were constructed using DI at critical point (CP) of growth stages (GS) and AUDPC in the three growing seasons, respectively. The CPs for estimating 1 000-kernel weight, crude protein content of grain and yield of wheat caused by powdery mildew were GS 11.1, GS 10.5.3 and GS l 0.5.3, respectively. Models based on DI at CP to estimate the percentage of loss of 1000-kernel weight, crude protein content of grain and yield were better than models based on AUDPC. And models of the percentage of loss of 1000-kernel weight, crude protein content and yield for 2011-2012 season were significant different from these for 2009-2010 and 2010-2011 seasons. These results indicated that besides powdery mildew, weather conditions also had influence on 1 000-kernel weight, crude protein content of grain and yield loss of wheat when powdery mildew occurred.  相似文献   
9.
水稻淀粉合成代谢相关基因与千粒重QTLs的连锁分析   总被引:6,自引:1,他引:6  
稻米淀粉的合成和积累是水稻千粒重形成的重要基础之一。在水稻千粒重QTLs定位分析基础上,对本研究克隆的14个水稻胚乳淀粉合成与积累相关基因及已报道的和预测的42个相关基因进行了电子定位分析,比较水稻淀粉合成代谢相关基因与千粒重QTLs的连锁关系。发现有38个基因位点与千粒重QTLs连锁,说明千粒重形成与胚乳淀粉积累与淀粉结构形成代谢密切相关。本研究结果将为进一步研究水稻产量形成的分子机理提供参考。  相似文献   
10.
Summary The effects of 1000-grain weight, its stability and the correlation coefficients with other traits of 50 barley varieties were studied at 18–20 environments. Additional material was used to study genotypic correlations among traits. Significant differences in stability of 1000-grain weight were found among varieties. Two-row varieties were on average more stable than 6-row varieties. The 1000-grain weight was among the most stable and grain yield the most variable traits. This was discussed in connection with stem reserves translocation to the grain. Consistently high yielding varieties had around average stability of 1000-grain weight. Regression coefficient, b, for 1000-grain weight was positively correlated with variance of log transformed data, both valid estimates for stability of 1000-grain weight. The correlation coefficient of 1000-grain weight with grain yield was positive or non-significant, with number of grains per tiller mainly negative and with volume weight it was positive. In 6-row barley, 1000-grain weight was positively correlated with grain yield, straw yield, total biological yield, and plant height, and negatively with number of tillers per m2 and number of grains per tiller.  相似文献   
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