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81.
82.
云南及周边地区农作物野生近缘植物 总被引:1,自引:0,他引:1
高爱农 《植物遗传资源学报》2013,14(2):193-201
"云南及周边地区生物资源调查"项目是国家科技部基础性工作专项,现已通过国家验收。云南及周边地区是低纬度高海拔地区,也是我国少数民族聚居区,农作物的种类和物种多样性及遗传多样性都十分丰富,并且孕育了丰富的农作物野生近缘植物。本文仅介绍云南及周边地区粮食作物、经济作物、蔬菜作物、果树作物的野生近缘植物,旨在为这些野生近缘植物的研究和开发,制定国家野生植物多样性保护政策提供基础数据和相关信息。 相似文献
83.
莱菔子素是由萝卜中萝卜甙水解形成的一种异硫氰酸酯类物质,在植物抗性和人类抗癌方面具有重要作用。本试验利用优化的HPLC检测方法测定了93份萝卜种质肉质根的莱菔子素含量,分析了不同来源地和不同类型萝卜种质莱菔子素含量分布。试验发现不同萝卜种质莱菔子素含量存在显著差异,其含量分布范围为34.445~1446.9 mg/kg﹒DW,最高含量约是最低含量的42倍;红皮白肉和绿皮白肉类型的萝卜种质莱菔子素平均含量较高,华东地区的萝卜种质莱菔子素平均含量显著高于其它来源地的萝卜种质。试验初步获得莱菔子素含量较高的萝卜种质2份,为进一步试验研究提供了良好的材料。 相似文献
84.
Addisu Mekonnen Peter J. Fashing Afework Bekele Nils Chr. Stenseth 《American journal of primatology》2020,82(4):e23074
Primates inhabiting human-modified landscapes often exploit matrix habitat to supplement their diet with cultivated foods, at times resulting in economic losses and conflict with local people. Understanding human-nonhuman primate interactions and the attitudes and perceptions of local people towards crop feeding species are crucial to designing effective species-based management plans. Over a 12-month period, we used scan sampling to study the consumption of cultivated foods and matrix use patterns by two habituated groups of Bale monkeys (Chlorocebus djamdjamensis), Ethiopian-endemic bamboo specialists, in two forest fragments (Kokosa and Afursa) set amidst human settlements and farmland in the southern Ethiopian Highlands. Further, we conducted interviews with local people to document their attitudes and perceptions towards Bale monkeys at the two sites. We found that Bale monkeys at Kokosa, a more degraded habitat by most measures, consumed significantly more cultivated foods than their counterparts at Afursa. Moreover, Bale monkeys at Kokosa spent significantly more time in the matrix than in the forest habitat, while monkeys at Afursa spent significantly less time in the matrix than in the forest habitat. Not surprisingly, local people displayed a more negative attitude towards monkeys inhabiting Kokosa than those inhabiting Afursa. The differences in Bale monkey cultivated food consumption and matrix use patterns—as well as in local people's attitudes and perceptions towards Bale monkeys—between Kokosa and Afursa are probably associated with differences in habitat structure, degree of habitat alteration, and land-use practices between the sites. We conclude that to ensure long-term coexistence between Bale monkeys and local people in human-modified landscapes, it is vital to incorporate nearby matrix habitats into management plans and to work closely with local communities to develop effective nonlethal crop protection strategies, thereby reducing the likelihood of negative interactions between Bale monkeys and humans. 相似文献
85.
通过定向进化(directed evolution)可以快速进行蛋白工程改良及重要基因功能研究,以获得新型农艺性状突变体。近期,中国科学院遗传与发育生物学研究所高彩霞团队和李家洋团队合作构建了新型的饱和靶向内源诱变编辑器(saturated targeted endogenous mutagenesis editors, STEMEs),并在植物中实现了基因的定向进化和功能筛选。该系统融合了现有的2种单碱基编辑技术,成功实现在植物体内同时诱导C:G>T:A、A:T>G:C双碱基编辑,通过靶向OsACC羧基转移酶结构域编码序列定向进化出水稻除草剂抗性植株。这种在体内进行基因定向进化的新方法,对于今后农作物重要农艺性状的筛选和功能基因研究具有重要作用。本文对STEME系统的组成、编辑效率和应用原理进行介绍,并与已有的定向进化方法进行比较,为加速作物种质资源创新研究提供参考。 相似文献
86.
Mona H. Soliman Taghreed S. Alnusaire Nessreen F. Abdelbaky Aisha A. M. Alayafi Mirza Hasanuzzaman Mohamed M. Rowezak Mohamed El-Esawi Amr Elkelish 《Phyton》2020,89(3):473-486
Salt stress is one of the major abiotic stress in plants. However,
traditional approaches are not always efficient in conferring salt tolerance. Experiments were conducted to understand the role of Trichoderma spp. (T. harzianum
and T. viride) in growth, chlorophyll (Chl) synthesis, and proline accumulation of
C. pepo exposed to salinity stress. There were three salt stress (50, 100, and
150 mM NaCl) lavels and three different Trichoderma inoculation viz. T. harzianum, T. viride, and T. harzianum + T. viride. Salt stress significantly declined the
growth in terms of the shoot and root lengths; however, it was improved by the
inoculation of Trichoderma spp. C. pepo inoculated with Trichoderma exhibited
increased synthesis of pigments like chl a, chl b, carotenoids, and anthocyanins
under normal conditions. It was interesting to observe that such positive effects
were maintained under salt-stressed conditions, as reflected by the amelioration
of the salinity-mediated decline in growth, physiology and antioxidant defense.
The inoculation of Trichoderma spp. enhanced the synthesis of proline, glutathione, proteins and increased the relative water content. In addition, Trichoderma
inoculation increased membrane stability and reduced the generation of hydrogen peroxide. Therefore, Trichoderma spp. can be exploited either individually
or in combination to enhance the growth and physiology of C. pepo under saline
conditions. 相似文献
87.
Rice blast disease is one of the most devastating diseases of rice
(Oryza sativa L.) caused by the fungus Magnaporthe oryzae (M. oryzae), and
neck blast is the most destructive phase of this illness. The underlying molecular
mechanisms of rice blast resistance are not well known. Thus, we collected 150
rice varieties from different ecotypes in China and assessed the rice blast
resistances under the natural conditions that favoured disease development in
Jining, Shandong Province, China in 2017. Results showed that 92 (61.3%) and
58 (38.7%) rice varieties were resistant and susceptible to M. oryzae,
respectively. Among the 150 rice varieties screened for the presence of 13 major
blast resistance (R) genes against M. oryzae by using functional markers, 147
contained one to eight R genes. The relationship between R genes and disease
response was discussed by analysing the phenotype and genotype of functional
markers. The results showed that the rice blast resistance gene Pita was
significantly correlated with rice blast resistance. Our results provided a basis for
the further understanding of the distribution of 13 major R genes of rice blast in
the germplasm resources of the tested rice varieties, and were meaningful for rice
disease resistance breeding. 相似文献
88.
Niaz Ahmad Mehboob-ur Rahman Zahid Mukhtar Yusuf Zafar Baohong Zhang 《Journal of cellular physiology》2020,235(2):666-682
Clustered regularly interspaced short palindromic repeats (CRISPR)-based genome editing, derived from prokaryotic immunity system, is rapidly emerging as an alternative platform for introducing targeted alterations in genomes. The CRISPR-based tools have been deployed for several other applications including gene expression studies, detection of mutation patterns in genomes, epigenetic regulation, chromatin imaging, etc. Unlike the traditional genetic engineering approaches, it is simple, cost-effective, and highly specific in inducing genetic variations. Despite its popularity, the technology has limitations such as off-targets, low mutagenesis efficiency, and its dependency on in-vitro regeneration protocols for the recovery of stable plant lines. Several other issues such as persisted CRISPR activity in subsequent generations, the potential for transferring to its wild type population, the risk of reversion of edited version to its original phenotype particularly in cross-pollinated plant species when released into the environment and the scarcity of validated targets have been overlooked. This article briefly highlights these undermined aspects, which may challenge the wider applications of this platform for improving crop genetics. 相似文献
89.
Xinyou Yin 《Annals of botany》2013,112(3):465-475
Background
Process-based ecophysiological crop models are pivotal in assessing responses of crop productivity and designing strategies of adaptation to climate change. Most existing crop models generally over-estimate the effect of elevated atmospheric [CO2], despite decades of experimental research on crop growth response to [CO2].Analysis
A review of the literature indicates that the quantitative relationships for a number of traits, once expressed as a function of internal plant nitrogen status, are altered little by the elevated [CO2]. A model incorporating these nitrogen-based functional relationships and mechanisms simulated photosynthetic acclimation to elevated [CO2], thereby reducing the chance of over-estimating crop response to [CO2]. Robust crop models to have small parameterization requirements and yet generate phenotypic plasticity under changing environmental conditions need to capture the carbon–nitrogen interactions during crop growth.Conclusions
The performance of the improved models depends little on the type of the experimental facilities used to obtain data for parameterization, and allows accurate projections of the impact of elevated [CO2] and other climatic variables on crop productivity. 相似文献90.