Lamichaney Amrit, Parihar Ashok K, Hazra Kali K, Dixit Girish P, Katiyar Pradip K, Singh Deepak, Singh Anil K, Kumar Nitin, Singh Narendra P
ICAR-Indian Institute of Pulses Research, Kanpur, India.
ICAR-Indian Agricultural Statistics Research Institute, New Delhi, India.
Front Plant Sci. 2021 Mar 29;12:635868. doi: 10.3389/fpls.2021.635868. eCollection 2021.
The apparent climatic extremes affect the growth and developmental process of cool-season grain legumes, especially the high-temperature stress. The present study aimed to investigate the impacts of high-temperature stress on crop phenology, seed set, and seed quality parameters, which are still uncertain in tropical environments. Therefore, a panel of 150 field pea genotypes, grouped as early ( = 88) and late ( = 62) maturing, were exposed to high-temperature environments following staggered sowing [normal sowing time or non-heat stress environment (NHSE); moderately late sowing (15 days after normal sowing) or heat stress environment-I (HSE-I); and very-late sowing (30 days after normal sowing) or HSE-II]. The average maximum temperature during flowering was about 22.5 ± 0.17°C for NHSE and increased to 25.9 ± 0.11°C and 30.6 ± 0.19°C in HSE-I and HSE-II, respectively. The average maximum temperature during the reproductive period (RP) (flowering to maturity) was in the order HSE-II (33.3 ± 0.03°C) > HSE-I (30.5 ± 0.10°C) > NHSE (27.3 ± 0.10°C). The high-temperature stress reduced the seed yield (24-60%) and seed germination (4-8%) with a prominent effect on long-duration genotypes. The maximum reduction in seed germination (>15%) was observed in HSE-II for genotypes with >115 days maturity duration, which was primarily attributed to higher ambient maximum temperature during the RP. Under HSEs, the reduction in the RP in early- and late-maturing genotypes was 13-23 and 18-33%, suggesting forced maturity for long-duration genotypes under late-sown conditions. The cumulative growing degree days at different crop stages had significant associations ( < 0.001) with seed germination in both early- and late-maturing genotypes; and the results further demonstrate that an extended vegetative period could enhance the 100-seed weight and seed germination. Reduction in seed set (7-14%) and 100-seed weight (6-16%) was observed under HSEs, particularly in HSE-II. The positive associations of 100-seed weight were observed with seed germination and germination rate in the late-maturing genotypes, whereas in early-maturing genotypes, a negative association was observed for 100-seed weight and germination rate. The GGE biplot analysis identified IPFD 11-5, Pant P-72, P-1544-1, and HUDP 11 as superior genotypes, as they possess an ability to produce more viable seeds under heat stress conditions. Such genotypes will be useful in developing field pea varieties for quality seed production under the high-temperature environments.
明显的气候极端情况会影响冷季豆类作物的生长和发育过程，尤其是高温胁迫。本研究旨在调查高温胁迫对作物物候、结实率和种子质量参数的影响，而这些在热带环境中仍不确定。因此，选取了150个豌豆基因型组成的群体，分为早熟（=88个）和晚熟（=62个）类型，通过交错播种使其暴露于高温环境下[正常播种时间或非热胁迫环境（NHSE）；适度晚播（正常播种后15天）或热胁迫环境-I（HSE-I）；极晚播（正常播种后30天）或HSE-II]。NHSE条件下开花期的平均最高温度约为22.5±0.17°C，HSE-I和HSE-II条件下分别升至25.9±0.11°C和30.6±0.19°C。生殖期（RP）（开花至成熟）的平均最高温度顺序为HSE-II（33.3±0.03°C）>HSE-I（30.5±0.10°C）>NHSE（27.3±0.10°C）。高温胁迫使种子产量降低（24 - 60%），种子发芽率降低（4 - 8%），对生育期长的基因型影响显著。在HSE-II条件下，成熟持续时间超过115天的基因型种子发芽率降幅最大（>15%），这主要归因于生殖期较高的环境最高温度。在HSE条件下，早熟和晚熟基因型的生殖期缩短了13 - 23%和18 - 33%，表明晚播条件下生育期长的基因型被迫早熟。不同作物阶段的累积生长度日数与早熟和晚熟基因型的种子发芽率均存在显著关联（<0.001）；结果进一步表明，营养期延长可提高百粒重和种子发芽率。在HSE条件下，尤其是HSE-II条件下，结实率降低了（7 - 14%），百粒重降低了（6 - 16%）。在晚熟基因型中，百粒重与种子发芽率和发芽速率呈正相关，而在早熟基因型中，百粒重与发芽速率呈负相关。GGE双标图分析确定IPFD 11 - 5、Pant P - 72、P - 1544 - 1和HUDP 11为优良基因型，因为它们在热胁迫条件下能够产生更多有活力的种子。这些基因型将有助于培育在高温环境下用于优质种子生产的豌豆品种。
