共查询到20条相似文献，搜索用时 265 毫秒
1.
采用常规耕作（T1）、秸秆覆盖（T2）、起垄覆膜膜侧种植（T3）、起垄无膜（T4）、无垄覆膜（T5）对玉米叶片光合作用和叶片水平上的水分利用效率以及产量和产量构成因素方面进行分析研究。结果表明,玉米叶片的净光合速率（Pn）、蒸腾速率（Tr）、气孔导度（Cond）、胞间二氧化碳浓度（Ci）和水分利用效率（WUE）在不同覆盖模式下均存在显著差异,且起垄覆膜膜侧种植模式下的Pn、Cond和WUE为最大,Tr和 Ci较低。叶片水分利用效率与净光合速率和气孔导度呈极显著正相关,相关系数分别为0.94、0.98;与蒸腾速率和胞间二氧化碳浓度呈显著负相关,相关系数分别为0.92、0.96。 2018 年 T3 处理产量最高,达 10 095 kg/hm2,较 T1、T2、T4、T5 处理分别高 23.18%、0.55%、19.32 %、3.71%;2019年T3处理产量最高,达10 248 kg/hm2,较T1、T2、T4、T5处理分别高21.84 %、12.47%、15.69%、6.03%。 相似文献
2.
为了提高小麦的抗旱能力,通过转基因将拟南芥 RD29A:DREB1A转入到小麦品种陇春30中,成功获得三个单拷贝本底DREB1A蛋白低表达水平的纯合转基因家系,并在干旱胁迫下测定了其生理指标及产量相关农艺性状。结果表明,与陇春30相比,转基因小麦的脯氨酸和可溶性糖含量以及SOD、CAT和POD活性都显著提高,H2O2含量、MDA含量和相对导电率均显著降低,株高、穗长、穗粒数、千粒重、地上生物量显著增加,说明 RD29A:DREB1A外源基因的导入能够显著增强陇春30的抗旱性。 相似文献
3.
为了解新麦草的种子产量及繁殖性状间的关系,对27份新麦草种质资源的单株种子产量与7个产量性状的关联性进行了分析。结果表明,新麦草的单株生殖枝数、穗轴节数、单穗小花数和千粒重与单株种子产量关联最密切,其相关性表现为单株生殖枝数＞千粒重＞穗轴节数＞单穗小花数。经通径分析,单株生殖枝数（X1）对单株种子产量（Y）直接效应最大,其余依次是单穗小花数（X4）、单穗小穗数（X3）、千粒重（X7）、穗轴节数（X2）和单穗结实种子数（X5）,其中单穗结实种子数和结实率对种子产量均表现为负效应,且未达到显著水平。经逐步回归分析得到回归方程Y= -9.880 2+0.27X1+0.012X4+2.011 1X7（R=0.805 8,P<0.001）,说明提高单株生殖枝数、千粒重、单穗小花数对新麦草增产的贡献最大,增加结实率也可间接提高新麦草的单株种子产量。 相似文献
4.
玉米直链淀粉是重要的食品和工业原料,高直链淀粉性状的产生受多种酶和基因-环境等因素的共同影响。玉米ae基因（amylose extender）突变导致子粒中直链淀粉含量增高、子粒表面皱缩、淀粉颗粒呈不规则形状、尺寸不均匀且表面基质蛋白增多,用于玉米育种后获得的品种直链淀粉含量升高,产量显著降低。通过将显性Ae突变体与16份优质玉米自交系杂交,对F1代植株进行开花期、株型、产量性状调查,分析F1代子粒总淀粉、直链淀粉的含量。结果表明,Ae突变体与不同的自交系杂交,F1代直链淀粉含量及产量的变化存在明显差异,与基因型有密切关系,以Ae突变体和W16F41、CA240为亲本杂交,可显著提高直链淀粉含量同时产量变化最小。根据F1代表现筛选直链淀粉含量提高、产量变化较小的双亲配制杂交种,可加速高直链淀粉玉米新品种培育进程。 相似文献
5.
水肥一体化条件下施氮量对小麦旗叶叶绿素荧光特性及产量的影响 总被引：6，自引：0，他引：6
为探讨水肥一体化条件下施氮量对小麦旗叶叶绿素荧光特性及籽粒产量的影响,以小麦品种济麦22为试验材料,设每公顷施纯氮0（N0）、150（N1）、180（N2）、210（N3）和240 kg（N4）五个处理,通过大田试验分析了不同处理间小麦旗叶PSⅡ 最大光化学量子效率（Fv/Fm）、PSⅡ实际光化学效率（ΦPSⅡ）、叶绿素相对含量、籽粒灌浆速率及产量的差异。结果表明,花后14~35 d,小麦旗叶Fv/Fm在N3和N4处理间无显著差异,但二处理显著高于其他处理。花后0~35 d,N3处理的旗叶ΦPSⅡ最高,施氮量再增加至N4时,ΦPSⅡ无显著变化。花后14~28 d,N3和N4处理的旗叶叶绿素相对含量显著高于其他处理;花后35 d,N3处理显著高于N4处理。粒重和灌浆速率在灌浆前期均随施氮量增加而降低;灌浆后期N3与N4处理间粒重和灌浆速率无显著差异,但二处理显著高于其他处理。籽粒产量在N3处理下最高;在施氮量增加至N4时,籽粒产量不再增加,且氮肥生产效率和氮肥农学效率分别下降了14.6%和24.0%。在本试验条件下,210 kg·hm-2是兼顾高产和高效的最佳施氮量。 相似文献
6.
高温胁迫下镁对小麦旗叶光合特性及产量的影响 总被引：1，自引：0，他引：1
为了解施镁对小麦后期高温胁迫的缓解效应,采用盆栽试验方法,以自然条件为对照(昼夜温度分别为26和16 ℃),研究了灌浆期花后14~20 d 和花后21~27 d高温胁迫（昼夜温度分别为32和22 ℃）下,施镁（20 kg·hm-2）对小麦产量和旗叶光合特性的影响。结果表明,高温胁迫显著降低了小麦产量,且以花后21~27 d高温胁迫影响最大;施镁能显著增加穗粒数、千粒重和籽粒产量。高温胁迫降低了旗叶叶绿素含量、净光合速率（Pn）、气孔导度（Gs）、蒸腾速率（Tr）、光化学效率（Fv/Fm）和实际光量子产量（ΦPSⅡ）,各指标均以花后21~27 d高温处理降幅最大,而胞间二氧化碳浓度（Ci）则表现出相反趋势;相同温度处理下,施镁则显著提高了旗叶叶绿素含量、Pn、Gs、Tr、Fv/Fm、ΦPSⅡ,表明镁素施用能有效缓解花后高温对叶片光合能力的伤害,有助于光合产物的积累和产量的形成。 相似文献
7.
ALA叶面肥对春小麦光合特性和灌浆速率的影响 总被引：3，自引：0，他引：3
为了解含5-氨基乙酰丙酸(ALA)的叶面肥对春小麦光合特性、灌浆特性及产量的影响,以宁春15号春小麦为试验材料,采用单因素随机区组试验,研究了拔节期喷施稀释2 000倍（T1）、1 500倍（T2）、1 000倍（T3）、500倍（T4）的ALA叶面肥和清水（CK）5个处理对春小麦灌浆期光合特性、灌浆特性和产量的影响。结果表明,拔节期喷施一定浓度的ALA叶面肥能提高小麦灌浆期叶片净光合速率(Pn)、蒸腾速率(Tr)和胞间CO2浓度(Ci),但以T2处理增幅最大。ALA叶面肥能够提高春小麦灌浆中前期的灌浆速率,以T2处理的效果最佳;可不同程度提高小麦产量及其构成因素,以T3处理成穗数、产量最高,与CK差异显著,较CK增产10.74%。综上所述,一定浓度ALA叶面肥能够改善春小麦的叶片光合特性,提高小麦籽粒产量,以稀释1 000~1 500倍施用效果较佳。 相似文献
8.
农杆菌介导法将抗草甘膦基因转入玉米自交系 总被引：1，自引：0，他引：1
利用农杆菌介导法将抗草甘膦基因(ssu-G2-aroA)转入优良玉米自交系R18-599和齐319,侵染后的愈伤组织转至潮霉素浓度为10 mg/L的筛选培养基上,继代筛选3轮,每轮3周;得到的抗性愈伤组织在含有潮霉素浓度为3 mg/L的分化培养基上进行分化,R18-599获得30株再生植株,齐319获得18株再生植株。经PCR鉴定后共得到7株转化抗性植株(4株R18-599、3株齐319)。经PCR-Southern及RT-PCR检测结果表明,ssu-G2-aroA基因已稳定整合到了玉米基因组中,并在RNA水平上得到表达。 相似文献
9.
为了解叶片衰老抑制基因 PSAG12-IPT在小麦遗传改良中的作用,利用共表达PSAG12和IPT的转基因小麦材料（TIPT-XN1376）与推广小麦品种陕麦159、周麦18、远丰175、西农979和郑麦9023杂交,并对其后代进行分子标记辅助选择和叶绿素含量测定,研究 PSAG12-IPT基因在小麦中的遗传特点及其与衰老和叶片叶绿素含量的关系。结果表明,150个转基因株系中,携带 PSAG12-IPT植株与不携带 PSAG12-IPT植株的分离比为110∶40,χ检验表明,符合3∶1的分离特点,说明 PSAG12-IPT基因以单基因形式在子代中稳定遗传。携带 PSAG12-IPT的F2株系平均叶绿素含量（55.4 mg·g-1）比不携带 PSAG12-IPT的F2株系（51.7 mg·g-1）提高7%,说明 PSAG12-IPT基因能够降低植株叶片叶绿素的降解速率,使叶片维持较长持绿时间,延缓叶片衰老。 相似文献
10.
CO2浓度升高对玉米叶片光合生理特性的影响 总被引：3，自引：0，他引：3
以沈糯3号为研究材料,利用开顶式气室(OTCs)法研究了二氧化碳(CO2)浓度升高处理下,玉米叶片叶绿素含量、光合生理特性及其子粒产量的变化,揭示CO2浓度升高对玉米光合生理特性及子粒产量的影响机理。结果表明,在整个生育期内,与对照相比,高浓度CO2处理下,玉米叶片叶绿素a、叶绿素b及叶绿素(a+b)的含量增加,而叶绿素a/b的值则先升高后降低;在整个处理期间,净光合速率均高于对照(p>0.05),升高幅度为12.6%～71.1%,气孔导度低于对照(p>0.05),其降低幅度为2.9%～18.8%。处理至抽雄期和灌浆期,胞间CO2浓度分别增加152%和161%,均极显著高于对照(p<0.01);蒸腾速率的变化较小。高浓度CO2处理下,玉米穗粒数和穗粒重均明显高于对照(p<0.05)。CO2浓度升高在一定程度上促进了玉米的光合作用,从而使玉米子粒产量增加。 相似文献
11.
《Field Crops Research》2004,90(1):75-85
Determining plant response at the biochemical/physiological level to a changing global environment is a prerequisite for constructing accurate models to predict plant productivity. High temperature and CO2 impact plant biomass accumulation by altering the rate of net photosynthesis such that the measured rates differ greatly from the potential rates predicted from commonly used models. Such models are based on assumptions pertaining to biochemical limitations to net photosynthesis by the capacity of ribulose-1,5-bisphosphate carboxylase/oxygenase (Rubisco), the enzyme that ultimately limits the rate of photosynthetic CO2 fixation in C3 and C4 plants, or the capacity of electron transport to supply energy for Calvin cycle activity. Here we provide evidence that the impact of high temperature and CO2 on net photosynthesis can be accurately calculated from predictive models based solely on Rubisco kinetics if the modeled rate of photosynthesis is adjusted for heat and CO2-induced changes in the activation state of Rubisco. The activation state of Rubisco, which is regulated by the activity of Rubisco activase, thus appears to be the primary limitation to net photosynthesis at high temperature and/or CO2. This limitation to net photosynthesis has not been incorporated into common biochemical models, thus compromising their effectiveness. The expression of activase mRNA was not indicative of the central role of activase in the response of photosynthesis to high temperature thus revealing limitations of using a broad genomics approach to identify the impact of environmental stress on plant metabolism. 相似文献
12.
Yutaro Makino 《Plant Production Science》2018,21(1):39-50
Nitrogen (N) is one of the major nutrients influencing photosynthesis and productivity of C4 plants as well as C3 plants. C4 photosynthesis operates through close coordination between mesophyll (M) and bundle sheath (BS) cells. However, how the development of structural and physiological traits in leaves of C4 plants is regulated under N limitation remains uncertain. We investigated structural and physiological responses of leaves of the NADP-ME-type C4 grass Sorghum bicolor to N limitation. Plants were grown under four levels of N supply (.05 to .6 g N per 5-L pot). Decreasing N supply resulted in decreases in net photosynthetic rate, stomatal conductance, leaf N and chlorophyll contents, and the activity ratio of phosphoenolpyruvate carboxylase to ribulose 1,5-bisphosphate carboxylase/oxygenase and increases in δ13C values and photosynthetic N use efficiency. Low-N leaves were thinner and had smaller photosynthetic cells, especially in M, resulting in lower M/BS tissue area ratio, and contained smaller and fewer chloroplasts. The BS chloroplasts in the low-N leaves accumulated abundant starch grains. The number of thylakoids per granal stack was reduced in M chloroplasts but not in BS chloroplasts. The low-N leaves had thicker cell walls, especially in the BS cells, which might be associated with less negative δ13C values, and fewer plasmodesmata in the BS cells. These data reveal structural and physiological responses of C4 plants to N limitation, most of which would be related to cellular N allocation, light use, CO2 diffusion and leakiness, and metabolite transport under N limitation. 相似文献
13.
《Plant Production Science》2013,16(3):165-173
AbstractEleocharis retroflexa (Poir.) Urban ssp. chaetaria (Roem. & Schult.) T. Koyama, an amphibious leafless sedge, grows not only under terrestrial conditions but also under completely submerged aquatic conditions. We investigated the photosynthetic traits and structural features of the culms, which are the photosynthetic organs, in the terrestrial and submerged forms of this species and compared them with those of other amphibious species of Eleocharis which are known to change the photosynthetic modes. The culms of the terrestrial form had Kranz anatomy with well-developed Kranz (bundle sheath) cells and high levels of C4 enzyme activity typical of the NAD-malic enzyme (NAD-ME) subtype of C4 metabolism. They also had a δ 13C value typical of C4 plants, indicating that the terrestrial form fixes carbon through the C4 pathway. The culms of the submerged form had not only a Kranz-like anatomy but also revealed anatomical traits typical of leaves of submerged aquatic plants. The activities of the C4 enzymes in the submerged form were lower than those in the terrestrial form, but were still in the range typical of G4 plants, 14C pulse-12C chase experiments with the submerged form indicated that almost all of the fixed 14C was incorporated into G4 compounds, and subsequently the raioactivity was transferred into C3 compounds and sucrose. The submerged form showed no diurnal fluctuation in malate level. These data demonstrate that a C4 metabolism is operative even in the submerged form. This unique amphibious C4 plant provides an intriguing example of the physiological and ecological adaptability of C4plants. 相似文献
14.
ABSTRACTThe successful introduction of the C4 pathway into C3 crops would increase photosynthetic rates and crop productivity. However, our poor understanding of how Kranz leaf anatomy develops poses a great obstacle. In particular, the origin, development, and genetics of bundle sheath (BS) cells in C4 plants are key points to elucidate. Here we report that Elymus tsukushiensis, a common C3 grass of the subfamily Pooideae, contains chloroplasts in the mestome sheath (MS) cells of the leaf, unlike most MS cells of C3 grasses. The chloroplasts are smaller than those of mesophyll cells. Immunogold localization showed that the chloroplasts and mitochondria of MS cells, respectively, accumulate ribulose 1,5-bisphosphate carboxylase/oxygenase and a photorespiratory enzyme, glycine decarboxylase, as in mesophyll cells. Thus, we suggest that the MS cells have weak photosynthetic and photorespiratory functions. This finding provides an insight into the development and evolution of C4-type BS cells in leaves of C3 grasses. 相似文献
15.
以玉米进行C4光合的全展第5位叶片为材料,分析从叶基部到顶部的解剖结构和叶绿素含量变化,研究玉米C4光合叶片"花环"结构随叶片发育的变化规律。结果表明,玉米第5位叶从基部到顶部都具有完整的典型"花环"结构,维管束鞘细胞(BSC)和叶肉细胞(MC)的体积在叶片发育过程中具有渐变性,从叶基部到顶部BSC和MC均呈先增大后变小的趋势,而且叶绿素a、b和a+b含量呈相同的变化趋势,说明BSC和MC细胞体积与叶绿素含量的变化具有相关性。叶绿素a/b总体呈上升趋势,说明玉米第5叶基部到顶部的光合途径存在C3向C4转变的过程。玉米第5叶不同部位C4光合途径发育的渐变性比前3叶更为明显。 相似文献
16.
蜀恢881含玉米C4型pepc基因改良系的遗传背景及其光合特性 总被引：6，自引：1，他引：5
从通过分子标记辅助选择育成的含玉米C4型pepc基因蜀恢881中筛选10株,利用530对SSR引物进行遗传背景分析,发现与蜀恢881表现差异的位点仅有1～4个,相似度在95.15%以上,最高的达9903%。进一步对相似度为9903%的转育玉米C4型pepc基因蜀恢881的6个生长时期测定有关光合指标,表明6个时期的PEPC酶活性均比蜀恢881增强,PEPC酶活性值最大时期是拔节期,为1264.2 μmol/(mg·h）,分蘖初期增加的幅度最大达到23.3倍;其净光合速率与蜀恢881相比,在分蘖初期、分蘖盛期、拔节期和始穗期都得到不同程度的提高,其中拔节期最高,达到22.3%。研究表明通过杂交利用C4型pepc基因特征引物对C4型pepc基因进行分子标记辅助选择,能够获得携有C4型pepc基因且与受体亲本遗传背景十分接近的籼型水稻材料,而且C4型pepc基因在新的遗传背景下能够高水平表达和稳定地遗传。据此,建立了分子标记辅助选择、光合生理生化指标鉴定和田间综合农艺性状考查相结合的筛选玉米C4型pepc基因水稻的技术体系;同时认为在拔节期进行转育C4型pepc基因水稻光合生理指标的测定和筛选的效果可能较理想。 相似文献
17.
Yuto Hatakeyama 《Plant Production Science》2016,19(4):540-551
In C3 plants, photosynthetic efficiency is reduced by photorespiration. A part of CO2 fixed during photosynthesis in chloroplasts is lost from mitochondria during photorespiration by decarboxylation of glycine by glycine decarboxylase (GDC). Thus, the intracellular position of mitochondria in photosynthetic cells is critical to the rate of photorespiratory CO2 loss. We investigated the intracellular position of mitochondria in parenchyma sheath (PS) and mesophyll cells of 10 C3 grasses from 3 subfamilies (Ehrhartoideae, Panicoideae, and Pooideae) by immunostaining for GDC and light and electron microscopic observation. Immunostaining suggested that many mitochondria were located in the inner half of PS cells and on the vacuole side of chloroplasts in mesophyll cells. Organelle quantification showed that 62–75% of PS mitochondria were located in the inner half of cells, and 62–78% of PS chloroplasts were in the outer half. In mesophyll cells, 61–92% of mitochondria were positioned on the vacuole side of chloroplasts and stromules. In PS cells, such location would reduce the loss of photorespiratory CO2 by lengthening the path of CO2 diffusion and allow more efficient fixation of CO2 from intercellular spaces. In mesophyll cells, it would facilitate scavenging by chloroplasts of photorespiratory CO2 released from mitochondria. Our data suggest that the PS cells of C3 grasses have already acquired an initial structure leading to proto-Kranz and further C3–C4 intermediate anatomy. We also found that in the Pooideae, organelle positioning in PS cells on the phloem side resembles that in mesophyll cells. 相似文献
18.
C4 plants show higher photosynthetic capacity and productivity than C3 plants owing to a CO2-concentrating mechanism in leaves, which reduces photorespiration. However, which traits regulate the photosynthetic capacity of C4 plants remains unclear. We investigated structural, biochemical, and physiological traits associated with photosynthesis and resource use efficiency in 20 accessions of 12 species of Amaranthus, NAD-malic enzyme-type C4 dicots. Net photosynthetic rate (PN) ranged from 19.7 to 40.5 μmol m?2 s?1. PN was positively correlated with stomatal conductance and nitrogen and chlorophyll contents of leaves and was weakly positively correlated with specific leaf weight. PN was also positively correlated with the activity of the C3 enzyme ribulose-1,5-bisphoshate carboxylase/oxygenase, but not with the activities of the C4 enzymes phosphoenolpyruvate carboxylase and NAD-malic enzyme. Structural traits of leaves (stomatal density, guard cell length, leaf thickness, interveinal distance, sizes of mesophyll and bundle sheath cells and the area ratio between these cells) were not significantly correlated with PN. These data suggest that some of the biochemical and physiological traits are involved in interspecific PN variation, whereas structural traits are not directly involved. Photosynthetic nitrogen use efficiency ranged between 260 and 458 μmol mol?1 N s?1. Photosynthetic water use efficiency ranged between 5.6 and 10.4 mmol mol?1. When these data were compared with previously published data of C4 grasses, it is suggested that common mechanisms may determine the variations in resource use efficiency in grasses and this dicot group. 相似文献
19.
《Field Crops Research》1999,62(1):53-62
Maize was grown in the high-radiation arid summer environment of Davis, California, and its leaf photosynthetic rate was measured over diurnal courses on cloudless days with the leaf held perpendicular to the sunlight. On days of high atmospheric vapor pressure deficit (VPD), leaf photosynthesis reached a maximum in the late morning and then decreased gradually as the day progressed, though the soil was well irrigated. When CO2 concentration in the measurement chamber was raised to about 1000 μmol mol−1, photosynthesis was enhanced, but more in the afternoon than in the morning. As a result, rates measured at high CO2 in the morning and afternoon were essentially the same. There was also no difference in the curves of photosynthetic rate (A) versus intercellular CO2 concentration (Ci) for the morning and afternoon. Hence, photosynthetic capacity was similar for the two periods and there was no evidence of photoinhibition by the high photosynthetic photon flux density at noon. Further, Ci and photosynthetic rates A measured over a range of photon flux density were lower in the afternoon than in the morning. These results indicate that A at noon and early afternoon was more limited than in the morning by epidermal conductance (mostly stomatal). On a day of low VPD, however, midday depression in A and epidermal conductance were not evident for the well-irrigated plants. Without irrigation and with leaves at a lower midday water potential, midday reduction in conductance and A was much more marked, beginning late in the morning. Epidermal conductance of maize grown in the field in Davis is are not sensitive to VPD. Therefore, the midday reduction in conductance and A was more likely the result of low leaf water potential caused by high transpiration rates. 相似文献
20.
《Plant Production Science》2013,16(3):345-350
AbstractThe activity of ribulose-1,5-bisphosphate carboxylase/oxygenase (Rubisco) is a major limitation of photosynthetic CO2 assimilation in C3 plants. In order to find useful Rubisco for improvement of photosynthesis in rice under elevated CO2, we analyzed the catalytic turnover rate (kcat) of Rubisco in Poaceae including C3 alpine plants, C3 cold-resistant plants and C4 plants. Rubisco in these plants showed 1.1- to 2.8-fold higher kcat than that in rice. However, the most of high kcat Rubisco also showed a higher km for CO2 (Kc) than that of rice, indicating that increase in kcat led to decrease in the affinity for CO2. Rubisco in Festuca ovina, Phleum pratense and Sorghum bicolor showed relatively high kcat to Kc. Although the kcat of Rubisco in F. ovina and P. pratense was not so high (1.5-1.6 fold relative to rice), the Kc was comparable to that in rice and the amino acid sequence of RbcL shared higher identity to that in rice than that in S. bicolor. By contrast, Rubisco of S. bicolor showed considerably high kcat (2.5-fold relative to rice), which is considered to be the most important factor for improvement of photosynthesis. In our estimation, the expression of high kcat Rubisco of F. ovina and S. bicolor in rice could significantly enhance CO2 assimilation at Ci of 50 Pa, the level assumed to be reached by the middle of this century. 相似文献