Defense mechanism of leaves to environmental stress in fruit trees

1.测定了土壤施氮量对几种落叶果树叶片和根系非结构性碳水化合物积累的影响。叶片叶绿素含量、可溶性总糖含量、叶片和根系含氮量随施氮量的增加而增加，而叶片淀粉含量与施氮量成反比.随着叶片氮含量的增加，叶绿体中RuBisCO的积累和与RuBisCO特异性抗体的免疫反应程度增加。由于叶绿体内积累了大量的淀粉粒，因此，N-O树叶片中的RuBisCO被限制在叶绿体的外围.研究了不同氮肥用量对几种落叶果树成熟叶片叶绿素荧光的影响。光抑制的程度是通过监测 ...更多信息 有价值叶绿素荧光与最大叶绿素荧光之比（Fv/Fm）。在各物种中，Fv/Fm均受施氮量的影响。在缺氮条件下，该比例始终较低。研究了芒果树展开叶片的解剖和生理特征变化，以确定与叶龄相关的控制光合活性的因素。当未成熟的幼叶用DAPI染色时，在相同的叶肉组织中，一些叶绿体发出红色荧光，而另一些叶绿体发出黄色荧光。冲洗后不久，叶片中的气孔没有分化。当叶片达到28.6cm ~ 2时，气孔保卫细胞全部出现。与幼叶相比，绿色叶和成熟叶含有较高浓度的RuBisCO，但幼叶的光合活性（单位叶面积放氧量和可变荧光与最大荧光的比值）始终低于成熟叶。少

1. The effects of different amounts of nitrogen, applied in the soil, on the accumulation of no*tructural carbohydrate in leaves and roots were determined in several deciduous fruit trees. Leaf chlorophyll content, total soluble sugar, and nitrogen content of leaves and roots increased with increased application of nitrogen, whereas starch content of leaves was inversely proportional to the amount of nitrogen administered.2. The accumulation of RuBisCO and the extent of immunoreaction with RuBisCO-specific antibodies increased in chloroplasts with increases in the nitrogen content of leaves. RuBisCO in The leaves of N-O trees was restricted to the periphery of chloroplasts because large starch grains had accumulated within the chloroplasts.3. The effects of the application of different amounts of nitrogen fertilizer on the chlorophyll fluorescence were examined in mature sun-exposed leaves of several deciduous fruit trees. The extent of photoinhibition was determined by monitoring the … More ratio of valuable to maximum chlorophyll fluorescence (Fv/Fm). In each species, Fv/Fm was affected by the application of nitrogen fertilizer. The ratio was consistently low in nitrogen-deficient leaves.4. Changes in anatomical and physiological features of expanding leaves of mango trees were examined to identify the factors that control photosynthetic activity related to leaf age. When immature young leaves were stained with DAPI, some chioroplasts fluoresced red and others fluoresced a yellowish color in the same mesophyll tissues. Stomata did not differentiated in the leaves soon after flushing. When leaves reached a leaf size, 28.6 cm2, guard cells of stomata appeared all at once. Compared with young immature leaves, green and mature leaves contained higher concentration of RuBisCO.Photosynthetic activity, estimated in terms of the amount of oxygen evolved per unit leaf area and the ratio of variable to maximum chlorophyll fluorescence (Fv/Fm) , were consistently lower in young immaturte leaves than in mature leaves. Less