植物生长调节剂对茭白孕茭的作用研究

Effects of plant growth regulators on galls formation of Zizania latifolia

茭白(Zizania latifolia)是我国第二大水生蔬菜,具有很高的营养和药用价值,但其成熟季集中,价格优势不明显,因此提早孕茭已成为农民的迫切需求。研究表明茭白茎部菰黑粉菌(Ustilago esculenta)和植物内源激素含量是茭白孕茭的重要影响因素。基于此,通过随机区组试验,首先将8种不同的植物生长调节剂及其复配组合作为备选孕茭调节剂,每种孕茭剂选择4个不同的喷施时间,采用随机抽样法对采收期的茭白进行生长指标测定,同时采用组织切片和荧光定量PCR方法测定茭白中菰黑粉菌的生长状态,在不影响孕茭产量的情况下筛选可能提早孕茭的组合及其喷施时间,并再次进行随机区组试验进一步确认。对比分析结果表明,在分蘖期喷施对碘苯氧乙酸能促进菰黑粉菌适量增殖,在保障茭白产量的同时提早孕茭时间,是理想的促孕茭时间调节剂。

As the second major aquatic vegetable in China, Zizania latifolia is very popular for its high nutritional and medicinal values. However, Z. latifolia always appears centralized ripening, leading to a lack of price advantage. Therefore, early harvest has become the urgent needs of farmers. Studies show that the formation of swollen stem is closely related to the endophytic fungus, Ustilago esculenta and the levels of endogenous hormones. Therefore, 8 different plant growth regulators and its combinations were first selected as alternative gall formation regulators and 4 different spraying times were set, through the randomized block experiment. Random sampling method was adopted to measure the growth regulators during the harvest period. Furthermore, the real time fluorescence quantitative PCR and freehand slice method were performed to detect the growth status of U. esculenta. The combinations and their specific spraying time, which could promote earlier harvest were screened, and further confirmed through next randomized block experiment. Results show that 4-iodophenoxyacetic acid(4-IPOA), spraying at tillering stage, could promote the moderate proliferation of U. esculenta, induce galls formation earlier but not affect the yields. So 4-IPOA could be an ideal plant growth regulator for the purpose of earlier harvest of Z. latifolia.