首页 > 分享 > 花期短时高温对不同品种水稻颖花开放动态及产量的影响

花期短时高温对不同品种水稻颖花开放动态及产量的影响

花匠小妙招
2024-12-30 10:01

摘要： 以耐热型水稻品种N22和热敏型水稻品种YR343为材料，进行盆栽试验。从抽穗扬花当天开始，利用人工气候室进行高温处理，以32℃/25℃（昼/夜）为对照，设置38℃/30℃为高温处理，连续处理7d。分别于处理第1、3、5、7天取样，研究花期不同天数高温胁迫对水稻颖花开放动态、颖花生理特性及产量的影响。结果表明：（1）高温胁迫后水稻产量和结实率均呈降低趋势，其降幅与高温持续时间有关。高温处理7d时，品种N22的产量与结实率分别降低49.1%和37.4%，YR343分别降低85.1%和65.3%。（2）高温胁迫后，水稻的花药开裂率和花粉活性均出现不同程度降低，且高温持续时间越长，降幅越大。（3）高温胁迫后水稻的总颖花开放量显著降低，其中，N22与YR343分别降低33.3%和65.5%。花期高温还改变了水稻开花峰值和峰值出现时间，与常温相比，高温下N22的开花高峰提前1h出现，峰值比例下降0.5%，YR343峰值出现时间无变化，但峰值比例降低2.8%，高温胁迫下YR343出现了花期缩短的现象。（4）高温胁迫下，水稻颖花可溶性蛋白、可溶性糖及脯氨酸含量总体呈下降趋势；丙二醛及过氧化氢含量呈上升趋势；抗氧化酶活性呈先升后降趋势。综上所述，结实率的降低是导致水稻减产的主要原因。花期高温主要通过改变水稻颖花开放动态及其生理特性，降低花药开裂率和花粉活性，从而降低结实率，导致水稻减产。

关键词: 水稻, 短时高温, 颖花开放动态, 产量, 结实率

Abstract: Under the background of global warming, high temperature weather occurs frequently in the Yangtze River Basin, which has become the primary problem seriously affecting the safe production of rice in this region. In order to clarify the effects of short-term high temperature on the spikelet opening dynamics and yield of different rice varieties during flowering period, the heat-resistant rice variety N22 and heat-sensitive rice variety YR343 were used as experimental materials and planted in pots. From the day of heading and blooming, the artificial climate chamber was used for temperature treatment, with 32℃/25℃ (day/night) as the control, 38℃/30℃ as the high temperature treatment, and continuous treatment for 7 days. Samples were taken on the 1st, 3rd, 5th, and 7th days of treatment to study the effects of high temperature stress on the opening dynamics, physiological characteristics of spikelets and yield of rice in different days of flowering. The results showed that: (1) the yield and seed setting rate of rice showed a decreasing trend after high temperature stress, and the reduction range was related to the duration of high temperature. After 7 days of high temperature treatment, the yield and seed setting rate of N22 decreased by 49.1% and 37.4%, and that of YR343 decreased by 85.1% and 65.3%, respectively. (2) The anther dehiscence rate and pollen activity of rice decreased to varying degrees after high temperature stress during flowering, and the longer the high temperature lasted, the greater the decrease. (3) The total amount of spikelet opening of rice was significantly reduced under high temperature stress, in N22 and YR343, by 33.3% and 65.5%, respectively. The flowering peak and peak appearance time of rice changed under high temperature stress. Compared with the control, the flowering peak ratio of N22 and YR343 decreased by 0.5% and 2.8%, respectively, and the flowering peak of N22 appeared 1 h earlier, while that of YR343 did not change. And under the high temperature coercion, YR343 has a shortened flowering period. (4) The changes of the physiological indices of rice spikelets under high temperature stress were as follows: the contents of soluble protein, soluble sugar and proline generally decreased; the contents of malondialdehyde and hydrogen peroxide increased; the activity of antioxidant enzymes showed a trend of first increasing and then decreasing. In summary, the low seed setting rate is the main reason for the reduction in rice yield. High temperature stress leads to the reduction of rice yield, mainly by changing the spikelet opening dynamics and its physiological characteristics, reducing the anther dehiscence rate and pollen activity, and thus reducing the seed setting rate.

Key words: Rice, Short-term high temperature, Spikelet opening dynamics, Yield, Seed setting rate