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1.
The allelopathic water extracts (AWEs) may help improve the tolerance of crop plants against abiotic stresses owing to the presence of the secondary metabolites (i.e., allelochemicals). We conducted four independent experiments to evaluate the influence of exogenous application of AWEs (applied through seed priming or foliage spray) in improving the terminal heat and drought tolerance in bread wheat. In all the experiments, two wheat cultivars, viz. Mairaj‐2008 (drought and heat tolerant) and Faisalabad‐2008 (drought and heat sensitive), were raised in pots. Both wheat cultivars were raised under ambient conditions in the wire house till leaf boot stage (booting) by maintaining the pots at 75% water‐holding capacity (WHC). Then, managed drought and heat stresses were imposed by maintaining the pots at 35% WHC, or shifting the pots inside the glass canopies (at 75% WHC), at booting, anthesis and the grain filling stages. Drought stress reduced the grain yield of wheat by 39%–49%. Foliar application of AWEs improved the grain yield of wheat by 26%–31%, while seed priming with AWEs improved the grain yield by 18%–26%, respectively, than drought stress. Terminal heat stress reduced the grain yield of wheat by 38%. Seed priming with AWEs improved the grain yield by 21%–27%; while foliar application of AWEs improved the grain yield by 25%–29% than the heat stress treatment. In conclusion, the exogenous application of AWEs improved the stay green, accumulation of proline, soluble phenolics and glycine betaine, which helped to stabilize the biological membranes and improved the tolerance against terminal drought and heat stresses.  相似文献   
2.
果树自交不亲和性的遗传与生理机制及其研究   总被引:25,自引:5,他引:20  
在简要介绍植物(包括果树)自交不亲和性与生理控制机制的基础上,着重对梨、苹果、杏等果树自交不亲和性的研究进行了综述,内容包括花柱内花粉管生长特点、花柱S糖蛋白的特性与作用机理以及果树自交不亲和的分子生物学研究,并提出了该领域有待研究的问题。  相似文献   
3.
J. Q. Yan    Q. Z. Xue  Y. X. Wang 《Plant Breeding》1996,115(5):301-304
Significant differences of callus induction, green plant regeneration and culture efficiency were observed among restorer lines and their hybrids in rice. Average callus induction percentage of F1, hybrids was about twice that of their parents. Twenty doubled haploid (DH) lines that showed normal fertility with both indica and japonica CMS lines, were selected as widely compatible restorers (WCRs). TG8 derived from CPSLO17/Minghui 63 not only showed normal fertility to both indica and japonica test varieties and CMS lines, but also exhibited superior agronomic traits, in particular short plant, desired plant type, high tillerability, large panicles, good grain quality and resistance to rice blast disease. Strong heterosis for yield was observed in crosses between indica or japonica CMS lines and TG8. TG8 possessed a dominant, widely compatible gene (WCG) that was inherited from the variety CPSLO17. Results confirmed that the anther culture technique is a quick and effective way of developing widely compatible restorers in rice and that it is applicable to the direct use of intersubspecific heterosis with the three-line method.  相似文献   
4.
 ‘金都1号’火龙果是从中南美洲火龙果原种(Hylocereus costaricensis)与红肉种(H. polyrhizus)的杂交后代中选育出的新品种。果实短椭圆形,平均单果质量572.5 g,果肉深紫红色,可溶性固形物含量21.2%,可食率78.8%,味清甜,有玫瑰香味,品质优。生长健壮,易成花,自花亲和性好,丰产稳产性好,不易裂果,适宜在广西桂南及华南气候相似地区种植。  相似文献   
5.
为研究稻瘟病菌Magnaporthe oryzae不同菌株间的相互作用,选择与单抗性基因系水稻IRBL5-M (携带抗性基因Pi5)表现为亲和性的菌株HN52与非亲和性的菌株HN119为研究对象,将其单独或混合接种到单抗性基因系水稻IRBL5-M中,并通过荧光显微镜观察接种后水稻叶鞘的发病情况及病斑面积,测定接种后水稻内相关抗性基因OsWRKY45、OsNPR1、OsPR10、OsMAPK2的表达量以及活性氧的变化。结果显示,相较于单独接种亲和性菌株,混合接种后单抗性基因系水稻IRBL5-M病斑发病面积减少;混合接种中亲和性菌株HN52菌丝侵染能力降低,侵染菌丝细胞间扩展率显著降低73.13%;同时单抗性基因系水稻IRBL5-M中OsWRKY45、OsNPR1、OsPR10OsMAPK2抗性基因表达量显著增加,水稻叶片中活性氧含量增加,表明在菌株混合侵染过程中,非亲和性菌株可通过激发水稻的抗性反应来降低亲和性菌株对水稻的侵染程度。  相似文献   
6.
云南光壳稻亲和性品种的筛选与鉴定   总被引:5,自引:1,他引:5  
以IR36等11个灿稻品种和秋光等8个粳稻品种为测验种,对毫梅、毫秕等12个云南光壳稻亲和品种的亲和谱和亲和力进行了鉴定。结果表明,在供试的12个云南光壳稻亲和品种中,品种毫秕对10个灿稻和7个粳稻测验种表现亲和,亲和组合百分率最高(84.2%),亲合组合百分率在60%以上的还有毫梅(75.0%)和镰刀谷(68.4%);亲和力最好的是大白糯,其与灿、粳测验种表现亲合的各组合的F1平均小穗结实率为7  相似文献   
7.
NaCl胁迫对骆驼蓬属植物渗透调节作用的影响   总被引:4,自引:0,他引:4  
研究NaCl处理对骆驼蓬属植物幼苗生物量、植株中主要无机离子和有机溶质的含量及渗透调节能力的影响。结果表明,骆驼蓬在NaCl浓度小于200 mmol/L,骆驼蒿和多裂骆驼蓬小于100 mmol/L时促进根系和地上部干重的增加,超过相应浓度时,幼苗生物量明显下降。3种植物根系和叶片的Na 和Cl-含量随NaCl浓度升高而增加,NO3-含量及K /Na 比则下降,K 对Na 的选择性吸收和运输SK,Na增大,但多裂骆驼蓬叶片的离子运输SK,Na则降低,Ca2 、Mg2 含量有升有降。无机离子占总计算渗透势(COP)的68.37%~83.82%,但随NaCl浓度增大而降低;可溶性糖和氨基酸含量随NaCl浓度增大明显增加,有机酸和脯氨酸变化不明显。有机物质约占COP的16.18%~31.63%,且随NaCl浓度提高而增大。骆驼蓬、骆驼蒿和多裂骆驼蓬的渗透调节能力随NaCl浓度增加而增强,其中叶片的渗透调节能力大于根系,渗透调节能力骆驼蓬>骆驼蒿>多裂骆驼蓬,表明骆驼蓬比骆驼蒿和多裂骆驼蓬具有更强适应盐渍生境的能力。  相似文献   
8.
During winter when the active layer of Arctic and alpine soils is below 0 °C, soil microbes are alive but metabolizing slowly, presumably in contact with unfrozen water. This unfrozen water is at the same negative chemical potential as the ice. While both the hydrostatic and the osmotic components of the chemical potential will contribute to this negative value, we argue that the osmotic component (osmotic potential) is the significant contributor. Hence, the soil microorganisms need to be at least halotolerant and psychrotolerant to survive in seasonally frozen soils. The low osmotic potential of unfrozen soil water will lead to the withdrawal of cell water, unless balanced by accumulation of compatible solutes. Many microbes appear to survive this dehydration, since microbial biomass in some situations is high, and rising, in winter. In late winter however, before the soil temperature rises above zero, there can be a considerable decline in soil microbial biomass due to the loss of compatible solutes from viable cells or to cell rupture. This decline may be caused by changes in the physical state of the system, specifically by sudden fluxes of melt water down channels in frozen soil, rapidly raising the chemical potential. The dehydrated cells may be unable to accommodate a rapid rise in osmotic potential so that cell membranes rupture and cells lyse. The exhaustion of soluble substrates released from senescing plant and microbial tissues in autumn and winter may also limit microbial growth, while in addition the rising temperatures may terminate a winter bloom of psychrophiles.Climate change is predicted to cause a decline in plant production in these northern soils, due to summer drought and to an increase in freeze-thaw cycles. Both of these may be expected to reduce soil microbial biomass in late winter. After lysis of microbial cells this biomass provides nutrients for plant growth in early spring. These feedbacks, in turn, could affect herbivory and production at higher trophic levels.  相似文献   
9.
Yang Zhuping 《Euphytica》1997,95(3):253-258
Following anther culture of various F1 hybrids of indica restorer (R) lines/wide compatible varieties (WCVs) and japonica R lines/WCVs, the homozygous diploid plants (2n) generated were test-crossed with indica WA type cytoplasmic-genetic male sterile (CMS) line Zhanshan 97A (WA), indica testers Nanjing 11 and Nante, japonica BT CMS line Hanfeng A (BT), and japonica testers Balilla and Akihikari to identify widely compatible restorer lines. The results of this study showed that among the diploid pollen plants generated from F1 hybrids of indica R lines/WCVs, 36.7% and 64.7% possessed normal fertility restoration ability (rate of seed-setting > 80%) to Hanfeng A and Zhanshan 97A, respectively. 71.3% and 32.3% had normal fertility restoration ability to Hanfeng A and Zhanshan 97A, respectively, in diploid pollen plants derived from the japonica R lines/WCVs F1's anther culture. Several widely compatible R lines were selected from anther culture of F1 hybrids of indica R lines/WCVs and japonica R lines/WCVs. These widely compatible R lines derived from diploid pollen plants showed good wide compatibility and restoration ability both to WA and BT type CMS lines. Strong standard heterosis of major agronomic traits and yield traits was observed in F1 test-crosses of widely compatible R lines with Hanfeng A and Zhanshan 97A. The wide compatibility in widely compatible R lines H17, H158 and H281 was studied by a set of three-way crosses. Segregation of the fertile plants with seed-setting rate > 70% and semi-fertile plants with seed-setting rate > 69.9% agreed with a ratio of 1:1, indicating that wide compatibility in these widely compatible R lines is governed by a pair of major genes. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   
10.
分析了广亲和品种02428,CP—SLO_(17)和轮回422与籼、粳稻杂种F_1、F_2及F_3世代亲和力与颖尖色的遗传特点,结果表明,具有一个广亲和品种的组合,F_1花粉育性与结实率正常,均在70%以上,F_2结实率呈连续变异,但主要分布在60~80%区域,平均结实率65.1%,F_3育性变异度与F_2基本一致,但平均结实率有明显提高。两个广亲和品种间杂交后代育性显著提高,F_2结实率低于60%的单株较少,而不含广亲和品种的组合F_1表现半不育,F_2呈正态分布,平均结实率43.4%,主要分布在40~60%之间。以上说明广亲和基因是存在的,广亲和力既受主效基因支配,也有微效基因参与作用。颖尖色出现3∶1或9∶7分离,有色颖尖与高结实率连锁明显,因此,颖尖色可以作为选择广亲和基因的标记性状。  相似文献   
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