不同条件育秧提高水稻秧苗抗逆性的研究

稻麦轮作系统中,麦秸还田腐解产生的有毒有害物质可对下茬水稻幼苗产生不利影响,有效减缓或避免其负面影响对于水稻生产尤为重要,而筛选能够提高水稻秧苗抗性的育秧技术不失为重要途径。通过采用5种不同育秧条件对水稻秧苗进行抗性锻炼,以期提高水稻秧苗对麦秸还田条件的抗逆性和适应性,并在移栽后采取相同的栽培措施(氮素和水肥管理)对其进行评估。试验结果表明,干旱及低营养条件下育秧均降低了水稻株高、生物量以及叶绿素含量,且增加了水稻植株丙二醛含量和脯氨酸含量,使水稻的生长发育受到抑制;而施用秸秆、浇施秸秆腐解液以及酚酸混合液进行育秧的处理均增加了水稻株高、地上部鲜重、叶绿素含量、总根长、根表面积、根体积、根尖数、根分枝数和平均根直径,且均降低了水稻植株丙二醛含量和脯氨酸含量,提高了水稻秧苗对麦秸腐解产生负面影响的抗逆性和适应性。通过在水稻育秧期添加适量麦秸、麦秸腐解液或酚酸混合液均可有效提高水稻秧苗对麦秸还田条件的适应性。

Study on Different Methods of Rice Seedling Raising to Improve Its Resistance

In rice wheat rotation system, the toxic and harmful substances produced from wheat straw decomposition can adversely affect the next stubble rice seedlings, how to reduce or avoid its negative impact is particularly important for rice production, and it is an important way to improve the resistance of rice seedling through rice seedling raising technique. In this experiment, five different resistance training methods were set up to investigate their resistance and adaptability of rice seedlings to the condition of wheat straw returning field. The results showed that drought and low nutrient stress conditions decreased plant height, biomass, chlorophyll content, and increased the content of malondialdehyde and proline in rice plant, i.e. the rice growth was inhibited. Meanwhile, the application of wheat straw, watering of wheat straw decomposed liquid and phenolic mixture on rice seedlings nursing increased the plant height, aboveground fresh weight, chlorophyll content, total root length, root surface area, root volume, root number, branch number, root diameter, and decreased the content of malondialdehyde and proline content in rice plants. Adding moderate amount of wheat straw or wheat straw decomposed liquid and phenolic mixture in rice seedling nursing period, can effectively improve the adaptability of rice seedling to the condition of wheat straw returning field.