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1.
Stipagrostis ciliata (Desf.) De Winter is a pastoral C4 grass grown in arid regions. This research work focused on assessing the growth of S. ciliata accessions derived from two different climate regions (a wet arid region in the Bou Hedma National Park in the central and southern part of Tunisia (coded as WA), and a dry arid region from the Matmata Mountain in the south of Tunisia (coded as DA)) under water stress conditions. Specifically, the study aimed to investigate the phenological and physiological responses of potted S. ciliata seedlings under different water treatments: T1 (200 mm/a), T2 (150 mm/a), T3 (100 mm/a) and T4 (50 mm/a). Growth phenology, net photosynthesis (Pn), stomatal conductance (gs), midday leaf water potential (Ψmd), predawn leaf water potential (Ψpd), soil water content (SWC) and soil water potential (Ψs) were observed during the water stress cycle (from December 2016 to November 2017). The obtained results showed that the highest growth potential of the two accessions (WA and DA) was recorded under treatment T1. The two accessions responded differently and significantly to water stress. Photosynthetic parameters, such as Pn and gs, decreased sharply under treatments T2, T3 and T4 compared to treatment T1. The higher water stress increased the R/S ratio (the ratio of root dry biomass to shoot dry biomass), with values of 1.29 and 2.74 under treatment T4 for accessions WA and DA, respectively. Principal component analysis (PCA) was applied, and the separation of S. ciliata accessions on the first two axes of PCA (PC1 and PC2) suggested that accession DA was detected in the negative extremity of PC1 and PC2 under treatments T1 and T2. This accession was characterized by a high number of spikes. For treatments T3 and T4, both accessions were detected in the negative extremity of PC1 and PC2. They were characterized by a high root dry biomass. Therefore, S. ciliata accessions responded to water stress by displaying significant changes in their behaviours. Accession WA from the Bou Hedma National Park (wet arid region) showed higher drought tolerance than accession DA from the Matmata Mountain (dry arid region). S. ciliata exhibits a significant adaptation capacity for water limitation and may be an important species for ecosystem restoration. 相似文献
2.
基于菰黑粉菌的全基因组序列,克隆得到了UeRbf1(GenBank登录号:MW375682),该基因的开放阅读框为1 281 bp,无内含子,编码426 个氨基酸,经预测具有3个C2H2锌指结构域,提示其具有转录调控功能。进一步在菰黑粉菌中敲除UeRbf1后进行体外生长及侵染试验,发现:在体外培养时,UeRbf1的缺失没有改变菌株的生长速率及单倍体形态,也未改变两个性亲和UeRbf1缺失突变体的融合及菌丝形成能力,但是融合菌丝的丝状生长能力显著减弱,而且在侵染时UeRbf1缺失突变体丧失了菌丝形成及丝状生长能力,人工接种野茭后也无法使其茎部膨大。以上结果表明,UeRbf1是调控菰黑粉菌丝状生长和侵染能力的一个重要因子。另外, UeRbf1缺失突变后,在体外融合及侵染时相关丝状生长和致病力的调控因子Biz1、Clp1、Hdp1和UeKpp6呈下调表达,其中Biz1的下调表达最为显著,在突变体中几乎不表达,说明UeRbf1对菰黑粉菌丝状生长和致病力的影响,可能是通过调控Biz1来实现的。 相似文献
3.
Ste12是最早在酿酒酵母(Saccharomyces cerevisiae)中发现的一类转录因子。之后在部分丝状真菌中也发现了该类转录因子的存在,并证明其能够参与调控生殖生长以及病原真菌的致病力。然而,苹果树腐烂病菌(Valsa mali)中是否存在该类转录因子以及其功能尚不明确。本研究基于生物信息学鉴定苹果树腐烂病菌中Ste12的同源基因,采用烟草瞬时表达系统进行蛋白亚细胞定位分析,利用酵母单杂技术进行转录激活功能分析,进而利用PEG介导的原生质体转化技术构建基因缺失突变体,并对其进行表型观察与分析。结果表明,苹果树腐烂病菌存在Ste12的同源基因,我们将其命名为VmSte12。该基因编码701个氨基酸,包含Ste同源结构域和C2H2锌指结构域。VmSte12定位于细胞核,并具有体外转录激活功能。与野生型相比,VmSte12敲除突变体生长速率平均下降10.1%,分生孢子器数量平均下降94.6%,致病力平均下降27.4%。可见,VmSte12具有Ste12类转录因子特征,并且极有可能在腐烂病菌的生长、繁殖、致病等方面发挥重要作用。 相似文献
4.
HU Xiaoxing 《干旱区科学》2019,11(6):824-836
In the arid and semi-arid areas of China, rainfall and drought affect the growth and photosynthetic activities of plants. Gross primary productivity (GPP) is one of the most important indices that measure the photosynthetic ability of plants. This paper focused on the GPP of two representative grassland species (Stipa krylovii Roshev. and Allium polyrhizum Turcz. ex Regel) to demonstrate the effect of a temporal rainfall on the two species. Our research was conducted in a temperate grassland in New Barag Right Banner, Hulun Buir City, Inner Mongolia Autonomous Region of China, in a dry year 2015. We measured net ecosystem productivity (NEP) and ecosystem respiration flux (ER) using a transparent chamber system and monitored the photosynthetically active radiation (PAR), air and soil temperature and humidity simultaneously. Based on the measured values of NEP and ER, we calculated the GPP of the two species before and after the rainfall. The saturated GPP per aboveground biomass (GPPAGB) of A. polyrhizum remarkably increased from 0.033 (±0.018) to 0.185 (±0.055) μmol CO2/(gdw?s) by 5.6-fold and that of S. krylovii decreased from 0.068 (±0.021) to 0.034 (±0.011) μmol CO2/(gdw?s) by 0.5-fold on the 1st and 2nd d after a 9.1 mm rainfall event compared to the values before the rainfall at low temperatures below 35°C. However, on the 1st and 2nd d after the rainfall, both of the saturated GPPAGB values of S. krylovii and A. polyrhizum were significantly lower at high temperatures above 35°C (0.018 (±0.007) and 0.110 (±0.061) μmol CO2/(gdw?s), respectively) than at low temperatures below 35°C (0.034 (±0.011) and 0.185 (±0.055) μmol CO2/(gdw?s), respectively). The results showed that the GPP responses to the temporal rainfall differed between S. krylovii and A. polyrhizum and strongly negative influenced by temperature. The temporal rainfall seems to be more effective on the GPP of A. polyrhizum than S. krylovii. These differences might be related to the different physiological and structural features, the coexistence of the species and their species-specific survival strategies. 相似文献
5.
北京地区十字花科蔬菜芜菁花叶病毒株系分化研究 总被引：2，自引：0，他引：2
对北京地区大白菜、不结球白菜、萝卜、甘蓝和花椰菜588份样本进行了病毒种类的鉴定,69.21%的样本感染了芜菁花叶病毒(Turnip mosaic Virus——TuMV)。并对其中33个TuMV分离物按抗病基因型进行了株系分化研究,均获得了台湾省报道的TuMV C1-C5 5个株系。TuMV-C4占分离物的42.4%,为主要株系,其余依次是C5、C1、C3和C2株系,这为十字花科蔬菜,特别是大白菜抗TuMV育种提供了依据。 相似文献
6.
DING Wenli 《干旱区科学》2021,13(7):730-743
Switchgrass is an introduced C4 grass in the semi-arid Loess Plateau of China, but there is a lack of information to assess its ecological invasive risk. In this study, Old World bluestems (native C4 grass) and switchgrass were sowed at five mixture ratios (8:0, 6:2, 4:4, 2:6 and 0:8) under two soil water levels (80% field capacity (FC) and 40% FC) and two nitrogen (N) treatments (0 and 100 mg N/kg dry soil, termed N0-unfertilized and N1-fertilized treatments, respectively) in a pot experiment in 2012. Biomass, root morphological traits and relative competitive abilities of these two species were analyzed. Results showed that biomass of both species was significantly greater under 80% FC or N fertilization, and switchgrass had a relatively larger root:shoot ratio (RSR). Total root length (TRL) and root surface area (RSA) of switchgrass were significantly higher under 80% FC irrespective of N treatment, while those of Old World bluestems were only significantly higher under N fertilization. N had no significant effect on TRL and RSA of switchgrass, while RSA of Old World bluestems significantly increased under 80% FC and N fertilization. Under 40% FC and N0-unfertilized treatment, the aggressivity of Old World bluestems was larger than zero at 2:6 and 4:4 mixture ratios of two species, whereas it was close to zero at 6:2 mixture ratio. Root competitive ability of switchgrass significantly increased under 80% FC or N fertilization. The aggressivity of Old World bluestems was negative at 6:2 mixture ratio under 80% FC and N fertilization, while it was positive at 2:6 mixture ratio. Switchgrass may become more aggressive when N deposition or rainfall increases, while a proper mixture ratio with appropriate water and N management could help with grassland management in the semi-arid Loess Plateau. 相似文献
7.
本文研究了小麦与秆锈菌3种典型类型非亲和性互作对秆锈菌生长发育的影响。结果表明,完全非亲和性互作ISr5-Ra/21C3 CKR(Sr5/P5)使秆锈菌芽管生长方向与叶片长轴夹角显著变小,比对应的亲和性互作ISr5-Sa/21C3 CKR(sr5/p5)平均小6.22°。高度非亲和性互作ISr 11-Ra/34M KG(Sr11/P11)使秆锈菌附着胞总分化率显著降低,接种后第1、2 d平均分别降低21.16%、33.37%,3种类型非亲和性互作对附着胞在气孔上的定位无影响。各类非亲和性互作对秆锈菌菌落扩展有不同程度极显著抑制作用。完全非亲和性互作、高度非亲和性互作及中度非亲和性互作ISr 6-Ra/34C2 MFR(Sr6/P6)侵染点寄主细胞坏死率分别为66.7%~76%、近100%及52.4%~87.1%。 相似文献
8.
稻瘟病抗性基因分析研究 总被引：5，自引：0，他引：5
本文报道了应用累积曲线分布法[1-3],在温室用我国多个菌系人工接种鉴定了丽江新团黑谷×会泽老来黄、丽江新团黑谷×抬头白谷两个组合11套F3系统.结果表明:会泽老来黄对A1、D1、G13个菌系的抗性是由一对显性基因控制的;对C13、F1两菌系的抗性是由两对显性基因控制的,其中一个控制高抗反应,另一个呈中抗反应.抬头白谷对C13、G1小种的抗性是由一对显性基因控制的;对A1、E1、F1三个菌系的抗性是由两对显性基因控制的;对D1菌系的抗性是由两对互补显性基因控制的. 相似文献
9.
从水稻(Oryza sativa L.)越光根面分离到一株固氮菌株1AG4,经生理生化特性鉴定,归类为争论产碱菌(Alcaligenes paradoxus)。1AG4的固氮酶乙炔还原活性(ARA)为13.06 C2H4 nmol/ml°h,固定15N2活性(N2FA)为2.052 15N a.e.%,表明1AG4具有较强的固氮能力。平皿拮抗试验证明1AG4可拮抗包括水稻三大病害病原菌在内的14种植物病原菌(Xanthomonas oryzae pv.oryzae ZHE173、Thanatephorus cucum eris、Piricularia oryzae Cavara、Alternaria longipes(Ellis et Everhart) Tisdale etW adkins、Cochliobolus sativus、Colletotrichum agaves Cavara、Colletotrichum lagenarium(Passerini) Ellis et Halsted、Colletotrichum panacicola Uyeda et Takimoto、Fusarium oxysporum f.niveum、Helminthosporium turcicum Passerini、Phytophthora parasitica Destur、Verticillium albo-atrum Reinkeet Berthold、Phytophthora melonis Katsura、Pseudomonas solanacearum Smith)的生长 相似文献
10.
11.
菰黑粉菌与茭白植株互作形成膨大肉质茎——茭白,已成为我国第二大水生蔬菜。作为一种二态性真菌,菰黑粉菌的二型态转换与侵染茭白密切相关,对茭白孕茭至关重要。本研究基于菰黑粉菌全基因组序列,采用tBlastn进行同源基因查找,克隆得到了玉米瘤黑粉菌Fuz7的同源基因UeFuz7。该基因cDNA全长1 308 bp,无内含子,编码435个氨基酸,在黑粉菌中相对保守。酵母双杂交实验发现,UeFuz7可与UeKpp2蛋白互作。同时其表达模式分析发现,在菰黑粉菌的二型态转换发生时UeFuz7的相对表达量最高。进一步通过PEG介导的原生质体转化获得UeFuz7突变体,表型分析发现:在二型态转换过程中,UeFuz7突变菌株的接合管形成和菌丝生长能力明显减弱。以上结果表明UeFuz7作用于菰黑粉菌的二型态转换。 相似文献
12.
猪毛菜属（Salsola L.）是藜科中最大的属之一,在新疆植物区系和植物资源开发利用中占有重要地位。通过对新疆猪毛菜属32种植物的果时花被片附属物和叶片解剖结构的特征及其地理分布的分析,结果表明：① 果期花被片的附属物可分为两类,其中具翅状附属物的形态更加丰富;② 得到4种叶片解剖结构类型,包括C3-SYMP型、C3-C4中间型、C4-SALS+H型和C4-SALS-H型。依据叶片解剖结构类型判断,新疆猪毛菜属中C4植物占到绝大多数;③ 在新疆分布的猪毛菜属种类以草本植物居多,其生境主要以旱生和盐生环境为主;④ 猪毛菜属植物分布在新疆的6个地理分布地区,其中以准噶尔亚地区分布最多,塔城伊犁亚地区分布次之; ⑤ 新疆猪毛菜属植物与国外邻近地区的共有种明显多于国内邻近地区。 相似文献
13.
Shanshan JIN 《干旱区科学》2019,11(3):446-460
Jujube(Ziziphus jujube Mill.) is a traditional economic forest crop and is widely cultivated in hilly areas of the Loess Plateau, China. However, soil desiccation was discovered in jujube plantations. Pruning is recognized as a water-saving method that can reduces soil water consumption. In this study, we monitored the jujube plots with control(CK), light(C_1), medium(C_2) and high(C_3) pruning intensities during the jujube growing period of 2012–2015 to explore the effect of pruning intensity on soil moisture and water use efficiency(WUE) of jujube plantations in the hilly Loess Plateau Region. The results showed that pruning is an effective method for soil water conservation in jujube plantations. Soil moisture increased with increasing pruning intensity during the jujube growing period of 2012–2015. C_1, C_2 and C_3 pruning intensities increased soil water storage by 6.1–18.3, 14.4–40.0 and 24.3–63.3 mm, respectively, compared to CK pruning intensity. Pruning promoted soil moisture infiltration to deeper soil layer. Soil moisture infiltrated to soil depths of 240, 280 and >300 cm under C_3 pruning intensity, 220, 260 and 260 cm under C_2 pruning intensity, 200, 240 and 220 cm under C_1 pruning intensity, and 180, 200 and 160 cm under CK pruning intensity in 2013, 2014 and 2015, respectively. Soil water deficit was alleviated by higher pruning intensity. In 2013–2015, soil water change was positive under C_2(6.4 mm) and C_3(26.8 mm) pruning intensities but negative under C_1(–20.5 mm) and CK(–40.6 mm) pruning intensities. Moreover, pruning significantly improved fresh fruit yield and WUE of jujube plants. Fresh fruit yields were highest under C_1 pruning intensity with the values of 6897.1–13,059.3 kg/hm2, which were 2758.4–4712.8, 385.7–1432.1 and 802.8–2331.5 kg/hm~2 higher than those under CK, C_2, and C_3 pruning intensities during the jujube growing period of 2012–2015, respectively. However, C_3 pruning intensity had the highest WUE values of 2.92–3.13 kg/m~3, which were 1.6–2.0, 1.1–1.2 and 1.0–1.1 times greater than those under CK, C_1 and C_2 pruning intensities, respectively. Therefore, C_3 pruning intensity is recommended to jujube plantations for its economic and ecological benefits. These results provide an alternative strategy to mitigate soil desiccation in jujube plantations in the hilly Loess Plateau Region, which is critical for sustainable cultivation of economic forest trees in this region. 相似文献
14.
Low-carbon economic development is a strategy that is emerging in response to global climate change. Being the third-largest energy base in the world, Central Asia should adopt rational and efficient energy utilization to achieve the sustainable economic development. In this study, the logarithmic mean Divisia index (LMDI) decomposition method was used to explore the influence factors of CO2 emissions in Central Asia (including Kazakhstan, Uzbekistan, Kyrgyzstan, Tajikistan and Turkmenistan) during the period 1992-2014. Moreover, decoupling elasticity and decoupling index based on the LMDI decomposition results were employed to explore the relationship between economic growth and CO2 emissions during the study period. Our results show that the total CO2 emissions decreased during the period 1992-1998, influenced by the collapse of the Soviet Union in 1991 and the subsequent financial crisis. After 1998, the total CO2 emissions started to increase slowly along with the economic growth after the market economic reform. Energy-related CO2 emissions increased in Central Asia, mainly driven by economic activity effect and population effect, while energy intensity effect and energy carbon structure effect were the primary factors inhibiting CO2 emissions. The contribution percentages of these four factors (economic activity effect, population effect, energy intensity effect and energy carbon structure effect) to the total CO2 emissions were 11.80%, 39.08%, -44.82% and -4.32%, respectively, during the study period. Kazakhstan, Uzbekistan and Turkmenistan released great quantities of CO2 with the annual average emissions of 189.69×106, 45.55×106 and 115.38×106 t, respectively. In fact, their economic developments depended on high-carbon energies. The decoupling indices clarified the relationship between CO2 emissions and economic growth, highlighting the occurrence of a 'weak decoupling' between these two variables in Central Asia. In conclusion, our results indicate that CO2 emissions are still not completely decoupled from economic growth in Central Asia. Based on these results, we suggest four key policy suggestions in this paper to help Central Asia to reduce CO2 emissions and build a resource-conserving and environment-friendly society. 相似文献
15.
JIN Xiaoming 《干旱区科学》2020,12(5):741-751
Sandy grassland in northern China is a fragile ecosystem with poor soil fertility. Exploring how plant species regulate growth and nutrient absorption under the background of nitrogen (N) deposition is crucial for the management of the sandy grassland ecosystem. We carried out a field experiment with six N levels in the Hulunbuir Sandy Land of China from 2014 to 2016 and explored the Agropyron michnoi Roshev. responses of both aboveground and belowground biomasses and carbon (C), N and phosphorus (P) concentrations in the plant tissues and soil. With increasing N addition, both aboveground and belowground biomasses and C, N and P concentrations in the plant tissues increased and exhibited a single-peak curve. C:N and C:P ratios of the plant tissues first decreased but then increased, while the trend for N:P ratio was opposite. The peak values of aboveground biomass, belowground biomass and C concentration in the plant tissues occurred at the level of 20 g N/(m2·a), while those of N and P concentrations in the plant tissues occurred at the level of 15 g N/(m2·a). The maximum growth percentages of aboveground and belowground biomasses were 324.2% and 75.9%, respectively, and the root to shoot ratio (RSR) decreased with the addition of N. N and P concentrations in the plant tissues were ranked in the order of leaves>roots>stems, while C concentration was ranked as roots>leaves>stems. The increase in N concentration in the plant tissues was the largest (from 34% to 162%), followed by the increase in P (from 10% to 33%) and C (from 8% to 24%) concentrations. The aboveground biomass was positively and linearly correlated with leaf C, N and P, and soil C and N concentrations, while the belowground biomass was positively and linearly correlated with leaf N and soil C concentrations. These results showed that the accumulation of N and P in the leaves caused the increase in the aboveground biomass, while the accumulation of leaf N resulted in the increase in the belowground biomass. N deposition can alter the allocation of C, N and P stoichiometry in the plant tissues and has a high potential for increasing plant biomass, which is conducive to the restoration of sandy grassland. 相似文献
16.
本文对经KMnO4、H2O2刺激掘氏疫霉(Phytophthora drechsleri)卵孢子萌发建立的单卵孢株群体应用于掘氏疫霉遗传研究的可行性做了研究。2个掘氏疫霉菌株(A1、A2交配型各1株)经聚碳膜间隔配对产生的卵孢子用KMnO4、H2O2以及不用上述氧化剂处理分别建立K、H、C 3个单卵孢株群体(卵孢子萌发率8-16%)。在群体水平上对来自同一亲本的上述3个群体生物学性状比较结果表明,H2O2处理刺激卵孢子萌发不影响生长速度、菌落形态、耐35℃高温生长、致病力及交配型的遗传稳定性,所建立的单卵孢株群体可用于上述性状的遗传研究;KMnO4处理导致掘氏疫霉A1和A2交配型在自交后代各自分离为A1、A2、A1A2和A2、A1A2,但不影响其他生物学性状的遗传稳定性,所建立的单卵孢株群体可用于除交配型性状以外的其他生物学性状的遗传研究,不宜用于交配型正常遗传规律的研究。用KMnO4处理掘氏疫霉A1或A2交配型菌株单株自交产生的卵孢子,从A1菌株自交后代获得A2和A1A2以及从A2菌株自交后代获得A1A2交配型单卵孢株的结果说明,掘氏疫霉异宗配合菌株体内可能同时包含控制A1和A2交配型的遗传因子,在正常条件下有1种交配型遗传因子不表达。KMnO4处理可望作为揭示交配型遗传本质的有用试验手段。 相似文献
17.
选择合适的启动子是植物抗病基因工程的关键性因素,病原菌诱导型启动子的获得将为植物提供更多的启动子选择。将大麦β-1,3-葡聚糖酶同工酶GⅢ基因启动子的缺失体片段P3与报告基因gus (β-葡聚糖酸醛苷酶基因)偶联,构建植物表达载体,通过农杆菌介导法转化水稻。PCR结果表明,所获得的10株潮霉素抗性水稻植株均呈PCR阳性;DNA印迹法结果显示,9株含P3/gus的融合基因已整合到水稻基因组DNA中。GUS组织化学染色及荧光法结果显示,P3缺失体驱动的gus在激发子诱导后,获得了高水平表达。T1代种子的GUS组织化学染色结果也表明,激发子可以诱导高水平的P3活性。 相似文献
18.
丙环唑是一种具有广谱活性的三唑类杀菌剂。本研究首次采用菌丝生长速率法建立了浙江省绍兴市、江苏省淮安市和黑龙江省尚志市不同地区的80株水稻恶苗病原菌(Fusarium fujikuroi)对丙环唑的敏感性基线,测定了丙环唑对水稻恶苗病菌的生理影响和对水稻的安全性。结果表明: 丙环唑对水稻恶苗病菌菌丝生长的有效抑制中浓度(EC50值)范围在0.029 8~0.211 0 μg·mL-1,EC50平均值为(0.106 7 ± 0.004 4) μg·mL-1。水稻恶苗病菌经0.1 μg·mL-1(EC50平均值)或3 μg·mL-1(EC90平均值)丙环唑处理后,分生孢子产量显著降低,细胞膜通透性显著升高;3 μg·mL-1丙环唑不影响水稻恶苗病菌细胞核的分布与定位,但可以使细胞壁缢缩,菌丝顶端膨大,破坏水稻恶苗病菌细胞膜和细胞器。丙环唑浓度为不超过200 μg·mL-1时,对水稻种子发芽率和株高无显著影响,同时可显著增加水稻鲜重;当浓度为500 μg·mL-1时,对水稻种子发芽率、株高和鲜重均无显著性影响;当浓度达到1 000 μg·mL-1时,发芽率显著降低但株高和鲜重无显著性差异;水稻种子发芽长度随丙环唑浓度升高而降低。本研究明确了丙环唑对水稻恶苗病菌的生物活性和对水稻的安全性,为丙环唑防治水稻恶苗病提供了指导,并进一步加深对丙环唑作用机理的认识。 相似文献
19.
蔓枯病菌侵染影响抗感甜瓜品种及杂种的光合特性分析 总被引：3，自引：0，他引：3
以抗病的甜瓜“PI157082”、“PI482398”和杂种1代“PI157082×PI482398”以及感病品种“白皮脆”为材料,研究了蔓枯病菌接种对甜瓜幼苗叶片叶绿素含量、气体交换参数和叶绿素荧光参数的影响。结果表明:蔓枯病菌接种后,不同抗性甜瓜的叶绿素含量、净光合速率、气孔导度、Fv/Fm、Fv′/Fm′和ΦPSII均有不同程度的降低,CO2浓度均有不同程度的上升。感病品种“白皮脆”的净光合速率、Fv′/Fm′、ΦPSII早于抗病材料达到显著水平;叶绿素含量、Fv/Fm显著低于接种前的时间跨度比抗病材料长;CO2浓度变化幅度比抗病材料大。在抗病材料中,杂种1代PI157082×PI482398的净光合速率、Fv′/Fm′显著降低的时间晚于亲本PI157082和PI482398;叶绿素含量、气孔导度、Fv/Fm一直与接种前差异不显著;CO2浓度变化幅度比亲本PI157082和PI482398小,说明杂种1代PI157082×PI482398可能比双亲有更严密的防御机制,使幼苗叶片保持较高的光合速率,体现出一定的杂种优势。 相似文献
20.
以抗病的甜瓜“PI157082”、“PI482398”和杂种1代“PI157082×PI482398”以及感病品种“白皮脆”为材料,研究了蔓枯病菌接种对甜瓜幼苗叶片叶绿素含量、气体交换参数和叶绿素荧光参数的影响。结果表明:蔓枯病菌接种后,不同抗性甜瓜的叶绿素含量、净光合速率、气孔导度、Fv/Fm、Fv′/Fm′和ΦPSII均有不同程度的降低,CO2浓度均有不同程度的上升。感病品种“白皮脆”的净光合速率、Fv′/Fm′、ΦPSII早于抗病材料达到显著水平;叶绿素含量、Fv/Fm显著低于接种前的时间跨度比抗病材料长;CO2浓度变化幅度比抗病材料大。在抗病材料中,杂种1代PI157082×PI482398的净光合速率、Fv′/Fm′显著降低的时间晚于亲本PI157082和PI482398;叶绿素含量、气孔导度、Fv/Fm一直与接种前差异不显著;CO2浓度变化幅度比亲本PI157082和PI482398小,说明杂种1代PI157082×PI482398可能比双亲有更严密的防御机制,使幼苗叶片保持较高的光合速率,体现出一定的杂种优势。 相似文献