Abstract Off-season flowering in red pitaya (Hylocereus sp.) can be achieved by night-breaking (NB) with artificial light in a noninductive season. To ensure abundant flowering, 4–6 h of NB is applied and often resulted in over flowering. This study compared the effects of four NB durations (4 h [2200–0200HR], 2 h [2300–0100HR], 1 h [2330–0030HR], and 0.5 h [2345–0015HR]) on floral bud formation in late autumn and early spring. In late autumn, the accumulated number of flowering shoots (FStotal) increased as the NB duration increased and 0.5 h was not sufficient to force 50 % of shoots flowering. The number of days to 50 % of the shoots flowering (FS50 %) was 35 for 1−4 h NB duration treatments. In late spring, the shoots were more responsive to the NB treatment and the duration effect on FStotal was less distinct; however, days to FS50 % decreased as the NB duration increased, and the shortest was 28 days in the 4-h treatment. Therefore, for obtaining shortest days to FS50 %, we suggest that the NB duration in late autumn and early spring should be 1 and 4 h, respectively. Thinning out the new sprouting are also in off-season production in early spring.

中文翻译：

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非诱导期夜间休息对火龙果花芽形成的季节性响应

摘要 红火龙果 (Hylocereus sp.) 的淡季开花可以通过在非诱导季节使用人造光进行夜间照明 (NB) 来实现。为确保大量开花，施用 4-6 小时的 NB，通常会导致过度开花。本研究比较了四种 NB 持续时间（4 小时 [2200-0200HR]、2 小时 [2300-0100HR]、1 小时 [2330-0030HR] 和 0.5 小时 [2345-0015HR]）对深秋花芽形成的影响和早春。在深秋，随着 NB 持续时间的增加，开花枝条的累积数量 (FStotal) 增加，0.5 小时不足以迫使 50% 的枝条开花。对于 1-4 小时 NB 持续时间处理，达到 50% 芽开花的天数 (FS50%) 为 35。在晚春，芽对 NB 处理更敏感，对 FStotal 的持续时间影响不太明显；然而，至 FS50% 的天数随着 NB 持续时间的增加而减少，最短的是 4 小时处理中的 28 天。因此，为了获得 FS50% 的最短天数，我们建议深秋和早春的 NB 持续时间分别为 1 和 4 小时。淡化新芽也在早春的淡季生产中。