多效唑和乙烯利对谷子穗颈、穗部性状及灌浆的影响

为探究既能抑制谷子植株的贪青徒长,又不影响谷子产量的最佳多效唑和乙烯利处理,以农大8号为试验材料,采用随机区组设计,在谷子不同生育时期分别叶面喷施多效唑和乙烯利,研究2种植物生长调节剂单施多效唑分别于拔节期前(A1)、拔节期(A2)、孕期期(A3)喷施;乙烯利分别于孕穗期(B1)、抽穗期(B2)、灌浆期(B3)喷施]和互作(A1B1、A1B2、A1B3、A2B1VA2B2、A2B3VA3B1、A3B2、A3B3)对谷子穗颈、穗部性状及灌浆的影响。结果表明,多效唑、乙烯利单施处理下,谷子穗颈粗、穗颈干物质显著提高,但其他穗颈参数无显著差异;谷子穗粗显著增加,在A1处理下达到最大值,较CK增加5.39%,穗重、穗粒重均在B2处理下最高,较CK分别增加7.25%、6.94%,穗长、穗码数无显著差异;籽粒灌浆速率有所提高,但秕谷率无显著变化。多效唑、乙烯利互作处理下,谷子穗颈粗、穗颈抗折力及干物质重显著增加,穗颈弯曲力矩、穗颈重心高度及含水量明显下降;谷子的穗长、穗码数显著减少,穗粗显著增加,在A1B3处理下达到最大,与CK相比,其穗长、穗码数分别减少20.11%、9.75%,穗粗增加10.15%,穗重、穗粒重均在A2B2处理下达到最大值,较CK分别增加11.45%、9.50%;随着籽粒灌浆速率的提高,秕谷率显著降低,在A2B2处理下达到最小值,较CK降低50.00%。表明与单施相比,两种调节剂互作效应更显著。在谷子拔节期前或拔节期喷施300 mg·L^-1多效唑后,在抽穗期或灌浆期追施400 mg·L^-1乙烯利最为适宜,而在孕穗期追施乙烯利会降低穗粒重,导致产量下降。本研究结果为谷子的化学调控和高产栽培提供了理论依据。

Effects of Paclobutrazol and Ethephon on the Panicle Neck,Panicle Traits and Grain Filling of Foxtail Millet

In order to explore the best treatment of paclobutrazol and ethephon which can inhibit the greedy and excessive growth of plants without affecting the yield of foxtail millet, the Nongda 8 was used as the experimental material, and the randomized block design was adopted. Paclobutrazol and ethephon were sprayed on the leaves of foxtail millet at different growth stages, respectively, and the effects of single applicationPaclobutrazol was sprayed befor jointing stage(A1), jointing stage(A2) and booting stage(A3), respectively. Ethephon was sprayed at booting stage(B1), heading stage(B2) and filling stage(B3).] and interaction(Those are A1B1, A1B2,A1B3,A2B1,A2B2,A2B3,A3B1,A3B2,A3B3) of two plant growth regulators on panicle neck, panicle traits and grain filling of Nongda 8 foxtail millet were investigated. The results showed that the panicle neck diameter and dry weight per centimeter of panicle neck was significantly improved with the single treatment of paclobutrazol and ethephon, but the other parameters of the panicle neck were not significantly different. The panicle diameter was significantly increased under A1 treatment, which was 5.39% higher than CK, and the panicle weight and grain weight of panicle were the highest under B2 treatment, which increased by 7.25% and 6.94% respectively compared with CK. There was no significant difference in panicle length and panicle code number. At the same time, the grain filling rate was improved, but the blighted grain rate did not change significantly. Under the interaction of paclobutrazol and ethephon, the panicle neck diameter, bending force and dry weight per centimeter of panicle neck of millet were increased significantly, while the bend moment, height of center gravity and water content of panicle neck decreased obviously. Compared with CK, the panicle length and panicle code number of millet decreased by 20.11% and 9.75% respectively, and the panicle diameter increased by 10.15% under A1B3 treatment. The panicle weight and grain weight of panicle reached the maximum under A2B2 treatment, which increased by 11.45% and 9.50% respectively compared with CK. With the increase of grain filling rate, the blighted grain rate decreased significantly, and reached the minimum under A2B2 treatment, which decreased by 50.00% compared with CK. The results showed that the interaction effect of the two regulators was more significant than that of single application, after spraying 300 mg·L^-1 paclobutrazol on the before jointing stage or jointing stage of foxtail millet, it is most suitable to pursue the application of 400 mg·L^-1 ethephon in heading or filling stage, while the application of ethephon at booting stages will decrease grain weight of panicle and yield decrease. The results of this study provided a theoretical basis for chemical regulation and high-yield cultivation of foxtail millet.