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排序方式： 共有169条查询结果，搜索用时 15 毫秒
1.
Mohammad Noor Hossain Miah Tetsushi Yoshida Yoshinori Yamamoto 《Soil Science and Plant Nutrition》2013,59(1):205-217
Abstract A water culture pot experiment was conducted to analyze the effects of N application during the ripening period (RP) on photosynthesis, dry matter production, and its impact on grain ripening and yield in two semidwarf indica type varieties viz. Gui Zhao 2 (GZ) and BR3 (BR) compared with a japonica type variety Koganemasari (KO) under four N rates viz. 0 (N0), 10 (N10), 20 (N20), and 40 (N40) mg L?1. Results showed that N application enabled to maintain a higher leaf area and delay leaf senescence in both indica and japonica type varieties but the decrease in the rate, of leaf area was higher in the former than in the latter and the rate was reduced with increasing N rates. Flag leaf photosynthesis and SPAD values of N treated plants were higher throughout the RP, showing the presence of a significant correlation either for each variety or all the varieties together. Higher photosynthetic rate was supported by higher leaf chlorophyll (SPAD value basis) content, stomatai conductance, and N concentration in leaf blades. Top dry matter content increased with increasing N rates mainly due to mean leaf area rather than NAR except for BR during RP but it was higher in KO than in GZ and BR. Reduction of shoot weight due to translocation of dry matter to panicles during RP was suppressed by N rates both in GZ and BR while shoot weight increased in the N-treated plants in KO. The dependency of KO on current photosynthates for panicle weight was found to be almost hundred percent while the contribution of stored carbohydrates in shoot before heading to panicle weight in GZ and BR was in the range of 4-27 and 33-54%, respectively and the rest was contributed by current photosynthates. The percentage increased with increasing N rates. Percentage of ripened grains (PRG) increased with increasing N rates in GZ and BR due to the increase in dry matter production and in the photosynthetic rates of apex leaves, despite the larger spikelet number and larger hull size. However, KO showed almost no variation although it had the highest PRG among the varieties. Brown rice yield followed the same pattern as that of PRG in GZ and BR and the highest yield was produced by BR followed by GZ and KO. These results suggest that N application during RP was more effective in increasing yield in the semidwarf indica type varieties than in the japonica type variety. 相似文献
2.
刘莹 《邯郸农业高等专科学校学报》2000,17(4):20-21,31
以华北麦区不同年代推广的小麦代表品种为材料,对其旗叶一生中的光合性能及SOD活性的变化做了比较研究,结果表明,当前推广的品种光合性能优于前期品种;在旗叶的衰老进程中,现品种SOD活性的下降幅度小于前期品种,这可能是现品种具有较长光合速率高值持续期,叶源量增大进而产量得以提高的内在生理基础之一。 相似文献
3.
LIU Xue-jing YIN Bao-zhong HU Zhao-hui BAO Xiao-yuan WANG Yan-dong ZHEN Wen-chao 《农业科学学报》2021,20(9):2343-2359
In order to identify the optimum period of spring water-restrictive irrigation for winter wheat(Triticum aestivum L.) in the Haihe Plain, China and elucidate its effects on flag leaf senescence and yield formation, field experiments were conducted at the Xinji Experimental Station of Hebei Agricultural University from 2016 to 2019 by using different irrigation regimes in spring, including the conventional regime involving two irrigation periods(control(CK), the 3-leaf unfolding stage and the anthesis stage) and a series of single, restrictive irrigation regimes(SRI) comprising irrigation at the 3-leaf unfolding stage(3 LI), 4 LI, 5 LI, and 6 LI. There are five major findings:(1) The senescence(determined by the green leaf area, GLA) in the 4 LI treatment occurred moderately earlier than that in CK, showed no significant difference with that in 5 LI and 6 LI, and occurred significantly later than that in 3 LI.(2) Compared with other SRI treatments, the GLA value and photosynthetic rate in 4 LI were 14.82 and 20.1% higher, respectively. Microstructural analysis of flag leaf also revealed that the mesophyll cells and chloroplasts were irregularly arranged under drought stress in 3 LI and 6 LI; however, drought stress had minimal negative effects on the microstructure in 4 LI and 5 LI.(3) Postponed irrigation in spring could significantly increase superoxide dismutase(SOD) and catalase(CAT) activities in the early stage of grain filling; however, these activities would subsequently decrease. Among the four SRI treatments, the overall enzyme activities were the highest in 4 LI, and the combined malondialdehyde(MDA) content in flag leaves in 4 LI and 5 LI was 14.5% lower on average than that in 3 LI and 6 LI.(4) The soluble sugar(SS) and proline(Pro) contents in 4 LI were the highest among the four SRI treatments; however, they were lower than those in CK. The abscisic acid(ABA) hormone content in 4 LI and 5 LI was lower than that in 3 LI and 6 LI, respectively, suggesting a smaller drought stress effect in 4 LI and 5 LI.(5) In two growing seasons, there was a larger number of spikes per unit area in 4 LI(i.e., 13.4% higher than that in 5 LI and 6 LI) and the 1 000-grain weight in 4 LI was the highest among the four SRI treatments(i.e., 6.0% higher than that in the other three SRI treatments). Therefore, a single restrictive irrigation regime at the 4-leaf unfolding stage is recommended to be effective in slowing down the senescence process of flag leaves and achieving high yield. 相似文献
4.
头季稻剑叶同化产物分配与再生稻产量的关系 总被引：1，自引：0，他引：1
以4个品种(组合)为材料,研究了头季稻剑叶同化产物的分配与再生稻产量的相关关系.结果表明:(1)约70%～75%的剑叶14C同化产物进入到了穗部,25%～30%残留在剑叶和茎鞘中;(2)约65%～80%的剑叶同化产物分配在倒一和倒二节间;(3)同化产物在穗部的分配比例与再生稻产量及所有的产量构成因子均呈负相关,同化产物在茎鞘、剑叶及其他叶片的分配比例与再生稻产量及所有的产量构成因子均呈正相关;(4)各节间的同化产物分配比例与再生稻相应节位产量呈显著正相关关系. 相似文献
5.
4 种植物生长调节剂对冬小麦旗叶细胞形态的影响 总被引：1，自引：0，他引：1
为明确植物生长调节剂对冬小麦叶片细胞的调控效应, 2008- 2009 年度在河北省藁城市以烯效唑、多效唑、麦巨金、麦业丰4 种植物生长调节剂2 种浓度的水溶液处理小麦, 研究了对旗叶叶片细胞形态的影响。结果表明:与对照(清水)相比, 4 种调节剂对旗叶不同环数叶肉细胞的比例影响不大, 仅常规浓度的麦巨金和加倍浓度的烯效唑使多环叶肉细胞的比例明显增加。4 种调节剂处理的小麦旗叶3 环叶肉细胞的长度和宽度都有所减小, 尤以宽度的减小更为明显。常规浓度下, 麦巨金处理的细胞宽度显著小于对照及其它调节剂处理。加倍浓度下, 多效唑处理的细胞长度和宽度都显著小于对照和其它调节剂处理。4 种调节剂常规和加倍浓度处理都使旗叶叶片的厚度增加, 且与对照叶片厚度的差异显著或极显著。2 种浓度的4 种生长调剂处理后小麦的籽粒产量均有所提高, 其中常规浓度的麦巨金、麦业丰和加倍后的多效唑、烯效唑对产量的提高效果最为显著, 这是不同调节剂对3 个产量构成因素的不同影响及其相互作用的结果。根据本研究结果, 在小麦高产、超高产条件下叶面积指数已经很大的情况下, 可以利用本研究中应用的生长调节剂, 使小麦叶片厚度增厚, 叶肉细胞变小, 从而达到改善叶片质量和群体质量的目的。 相似文献
6.
7.
理想水稻株型的选育与高产育种密切相关,而剑叶角度则是构成水稻理想株型的重要指标之一,同时也是影响水稻产量的重要因素。合理开发利用水稻中控制剑叶角度及产量相关的数量性状基因座位（QTL）,并结合分子育种技术,可更好地为高产制繁种目标服务。通过应用由244个株系组成的珍汕97B/密阳46重组自交系（RIL）群体,构建含256个分子标记的连锁图谱,采用QTL区间作图法对剑叶角度及主穗产量等5个性状进行定位分析,共检测到17个QTL,分布于染色体1、2、3、5、6、9、10、11。这些QTL对相应性状的贡献率介于3.46%~25.64%之间。在第1染色体上检测到控制5个性状的QTL,其中控制剑叶角度的两个QTL;在第2、3、9、10、11染色体上分别检测到各一个QTL;第5染色体上检测到控制剑叶、每穗总粒数和每穗实粒数的3个QTL;1个每穗实粒数和2个每穗实粒重的QTL分布于第6染色体上。多个区间表现出对两个性状的显著作用,其中第1染色体2个,第6染色体1个。相关性分析表明,较小的剑叶角度可通过提高结实率进而显著增加产量。 相似文献
8.
氮肥运筹及密度对中优752源库关系和剑叶温度的影响 总被引：2，自引：0，他引：2
以三系籼型杂交中稻中优752为材料,研究了氮肥运筹及密度对其源库关系和剑叶温度的影响。研究表明：在适宜施氮量的情况下,适当增加中后期施氮比例和适度稀植都能提高粒叶比和库源增量比、降低生育后期根系活力的衰退值,有利于源库协调。粒叶比和库源增量比与产量均显著正相关,生育后期根系活力的衰退值与产量极显著负相关。增施氮肥、增加中后期的施氮比例及适度稀植能降低剑叶温度。抽穗期及抽穗后25 d剑叶温度与产量呈极显著负相关,而抽穗期剑叶温度与抽穗期的伤流强度极显著负相关。 相似文献
9.
光照强度对冬小麦旗叶光合生理特性的影响 总被引：1，自引：0，他引：1
为建立冬小麦相应的光合作用模型提供数据支持,在20℃、不同光强梯度下,测定了冬小麦旗叶净光合速率(Pn)、气孔导度(Gs)、蒸腾速率(Tr)、胞间CO2浓度(Ci)等生理指标,研究自然条件下抽穗期冬小麦旗叶光合生理特性的变化规律。结果表明,光合速率随光照强度增加而增加并呈正相关(p<0.05),在光强度低于500μmol/(m2.s)时,小麦旗叶的光合速率快速增加;气孔导度随光强增强而增强并呈正相关(p<0.05),但在光强度低于100μmol/(m2.s)时气孔导度增幅很小;蒸腾速率随光强度的变化与光合速率趋势基本一致;胞间CO2浓度随光强度的增加呈先降低后增加趋势。 相似文献
10.
植物净光合速率是植物生产的基础,是体现植物生长状况的重要生理指标。本文将小麦旗叶高光谱波段反射率进行一阶导数变换后与净光合速率（Pn）进行相关性分析确定敏感波段,分别采用二次多项式逐步回归（QPSR）、偏最小二乘法（PLSR）、BP神经网络法（BPNN）3种方法构建小麦旗叶的净光合速率反演模型,并对3种模型的预测精度进行比较分析。结果表明：（1）将小麦旗叶的原始光谱进行一阶导数变换后与Pn进行相关性分析确定的敏感谱区集中在750~925 nm之间,确定的6个敏感波段分别是：760、761、767、814、815、889 nm;（2）基于QPSR、PLSR、BPNN3种方法以及敏感波段的反射率一阶导数构建的Pn估测模型预测精度都较高,说明用这3种方法以及敏感波段对Pn的估测是可行的,其中模型估算能力顺序为QPSR > BPNN > PLSR,说明小麦旗叶Pn的最佳高光谱分析模型为小麦叶片750~925 nm反射率一阶导数变化后的QPSR模型。 相似文献