【作者】 韩浩章；

【导师】 姜卫兵；

【作者基本信息】 南京农业大学 ， 果树学， 2004， 硕士

【摘要】 满足落叶果树低温需求量以顺利完成自然休眠是果树正常开花、结果的重要保证。若需冷量不足会引起生长发育障碍，不能使其萌发或萌发不整齐，并引起花器官畸形或败育，影响果树的正常生产。因此了解落叶果树的需冷量及其生理机制，探讨打破落叶果树芽体自然休眠的可能途径，对于果树设施栽培和南方地区果树引种栽培具有十分重要的意义。 本研究在2001～2003年越冬期间用低温模型（≤7.2℃）、0～7.2℃模型、犹他（Utah）模型三种方法，对苏南地区主要落叶果树梨、桃、葡萄、杏四个树种的需冷量进行研究。结果表明：应用三种模型统计的落叶果树需冷量数值存在差异，但以犹他（Utah）模型统计的落叶果树需冷量年际间差异较小；总体来看，砂梨和砂杂梨品种的需冷量为340h～530h（0～7.2℃模型）、340c.u～5 00c.u（犹他模型）和530h～830h（低温模型）；桃、杏为520h～900h（0～7.2℃模型）、590c.u～900c.u（犹他模型）和840h～1300h（低温模型）；葡萄为770h～980h（0～7.2℃模型）、820c.u～1000c.u（犹他模型）和1200h～1350h（低温模型）。 在大田条件下，以葡萄和油桃两个树种共四个品种为试材，研究了落叶果树芽体内活性氧及其清除系统、丙二醛和呼吸代谢的变化。结果表明：在整个自然休眠过程中供试树（品）种芽体内H₂O₂含量前期升高，保持一定时间的大致稳定后，在自然休眠解除前后迅速下降，H₂O₂与休眠有关；丙二醛含量在前期迅速下降，到最低点后保持基本稳定；SOD的变化规律与H₂O₂基本相似；CAT与之相反，在自然休眠前期开始降低，中期保持较低水平，自然休眠解除前后回升；POD在前期缓慢上升，深休眠期保持最高，休眠后期降低并保持稳定；呼吸速率前期缓慢上升，到最高点后迅速下降，自然休眠解除前后回升；两树种间需冷量的差异较大，各所测指标的含量或活性亦存在明显差异，而同一树种内需冷量不同的品种间这种差异不明显。 以藤稔葡萄和金山早红油桃为试材，在自然休眠进程中的不同阶段对芽体处理不同浓度的化学药剂并进行萌芽培养过程中，对芽体内活性氧及其清除酶系统、丙二醛和呼吸速率的变化进行了测定。结果表明：施用化学药剂能不同程度的提高芽体呼吸速率，降低CAT活性，提高H₂O₂含量，提高POD活性，但对SOD苏南地区主要落叶的果树需冷量及休眠解除生理机制的研究影响不明显。25%浓度的石灰氮对葡萄在1月3日²月7日施用能提高HZOZ含量，基本满足芽体对HZO，含量的积累需要，使芽体萌芽率达41 .6%一90%。水杨酸对葡萄解除休眠无效;1叭浓度的水杨酸对油桃在1月3日²月7日施用能有效控制芽体内H202含量，基本满足芽体对HZOZ含量的积累需要，使叶芽萌芽率达47%-88%，使花芽提前3一8天萌发。而石灰氮对金山早红油桃花芽解除休眠效果不明显，且存在药害。更多还原

【Abstract】 To satisfy Chilling requirement (CR) of deciduous fruit crops is an important guarantee for deciducxn fruit crops to sprout, blossom and bearing normally. If Chilling requirement of deciduous fruit crops is insufficient, production of deciduous fruit crops will be influenced because sprouting was delayed, floral organ became abnormal or abortion. So studying the physiological mechanism dormancy-release, chilling requirement of deciduous fruit crops and methods of dormancy-release are very important for protected cultivation of deciduous fruit crops and introduction of new varieties of fruit crops of southern area in china.Chilling requirement (CR) of main deciduous fruit crops in southern area of Jiangsu province were studied from November 2001 to February 2004. The results showed that CR of deciduous fruit crops, estimated by <7.2C chilling model ,0~ 7.2C chilling model and Utah model ,was difference between each other, while it was estimated by Utah model was less difference between different years. In one words ,values of CR measured of Pyrus pyrifolia and its hybrids were 340h~530h(0-7.2C chillingmodel), 340c.u~500 c.u (Utah model) and 530h~830h (< 7.2C chilling model) ,And those of apricot and nectarine varieties were 520h~900h(0~7.2C chillingmodel ), 590c.u~900 c.u (Utah model) and 840h~1300h (< 7.2C chilling model), and those of grape varieties were 770h~980h (0~7.2C chilling model), 820c.u~1000 c.u (Utah model) and 1200h~1350h (<7.2C chilling model) .Content of H2O2 and MDA, activities of antioxidant enzymes, and the respiratory ratio of grape and nectarine during nature dormancy-release were measured. The results showed that relative H2O2 content of grape and nectarine increased in early-dormancy stage, kept high level in deep-dormancy stage, and decreased later; content of MDA was high in early-dormancy stage and became a low level later; the change of SOD activities was same to that of H2O2.But the change of CAT activities was contrary to that of H2O2. POD activities increased in early-dormancy stage and reached the highest point in deep-dormancy stage, then decreased and kept at a low level later. Respiratory ratio increased in early-dormancy stage, the respiratory ratio of grape varieties reached a lowest point in deep-dormancy stage, while that of nectarine varieties was highest in deep-dormancy stage. A rise was found in stage of nature dormancy-release of grape and nectarine respiratory ratio. Chilling requirement between grape and nectarine has significant difference, but little difference between grape or nectarine.Content of H202 and MDA, activities of antioxidant enzymes, and the respiratory ratio of grape and nectarine, treated by CaCN2 and salicylic acid(SA) and glasshouse culture in different stage during nature dormancy-release, were studied. The results showed that CaCN2 and SA increased respiratory ratio, relative H2O2 content, POD activities, and decreased CAT activities, but has no significant effect on SOD activities. Treated by 25% CaCN2 from 3rd Jan. to 7th Feb. increased relative H2O2 content effectively, and satisfied the need of H2O2 content accumulation for buds to sprout, made sprouting ratio reach 41.6%~90%. Salicylic Acid had little effect on nature dormancy-release of grape; Treated by 10% SA from 3rd Jan. to 7th Feb to nectarine could regulate relative H2O2 content effectively, and satisfied the need of H2O2 content accumulation for buds to sprout, made leaf buds sprouting ratio reach 47%~88% and floral bud sprouting be advanced three to eight. CaCN2 had no significant effect on nature dormancy-release of nectarine.更多还原