Puccinia striiformis f. sp. tritici (Pst) is an important pathogen of wheat (Triticum aestivum L.) stripe rust, and the effector protein secreted by haustoria is a very important component involved in the pathogenic process. Although the candidate effector proteins secreted by Pst haustoria have been predicted to be abundant, few have been functionally validated. Our study confirmed that chitin and flg22 could be used as elicitors of the pathogenic-associated molecular pattern-triggered immune (PTI) reaction in wheat leaves and that TaPr-1-14 could be used as a marker gene to detect the PTI reaction. In addition, the experimental results were consistent in wheat protoplasts. A rapid and efficient method for screening and identifying the effector proteins of Pst was established by using the wheat protoplast transient expression system. Thirty-nine Pst haustorial effector genes were successfully cloned and screened for expression in the protoplast. We identified three haustorial effector proteins, PSEC2, PSEC17, and PSEC45, that may inhibit the response of wheat to PTI. These proteins are localized in the somatic cytoplasm and nucleus of wheat protoplasts and are highly expressed during the infection and parasitism of wheat.

Wheat pollen, which is characterized by its short lifespan, exhibits rapid germination after anthesis. The preservation of wheat pollen is contingent upon environmental factors including temperature, relative humidity, light, and wind. The aim is to explicate the process for efficiently storing wheat pollen, particularly with regard to breeding. The short longevity of wheat pollen grains renders it impractical to conduct tests for pollen viability and in vitro germination on a large scale. Herein, the impact of storage temperatures and duration was assessed on pollen viability and in vitro germination in order to optimize storage conditions for preserving pollen viability. Pollen grains from 50 diverse spring wheat genotypes, each with three replicates, were harvested and stored at temperatures of 22 °C, −20 °C, and 4 °C. Subsequently, pollen viability and in vitro germination rates were determined after storage for 1, 3, and 6 days. The results revealed that storage temperatures, durations, genotypes, and their interactions had a statistically significant impact on both pollen viability and in vitro germination. Notably, when pollen was kept at 22 °C, almost all genotypes exhibited a loss of pollen viability and in vitro germination after 1, 3, and 6 days of storage. Likewise, storage at −20 °C failed to extend pollen germination. However, at a storage temperature of 4 °C, the pollen of 36 wheat genotypes exhibited a range of 6–14% for in vitro pollen germination and even remained viable for 6 days. The ANOVA revealed a substantial variation in grain number per spike between wheat genotypes, thereby highlighting the significant influence of genetic variations on grain yield. Moreover, a slight positive association between the viability of wheat pollen and the number of grains was found in the current study, suggesting that a variety of factors affect the number of grains produced. Simple linear regression analysis further revealed a significant negative correlation between pollen viability, in vitro germination, and storage time and temperature. In conclusion, our findings underscore that 4 °C is the optimal temperature for preserving pollen viability and in vitro pollen germination in spring wheat for up to 6 days. The results of the present study suggests that the pollen viability of wheat is dependent on genotype, storage temperature, and storage duration. Thus, the 36 wheat genotypes identified during the present work could be efficiently maintained at 4 °C for short-term storage (6 days) and could be further used for genetic and breeding purposes.

穗发芽严重降低籽粒产量、品质和种用价值，是小麦育种和生产急需解决的难题. 为利用发芽抑制剂的化控途径有效防治穗发芽，研究了不同浓度的外源激素脱落酸（ABA）、水杨酸（SA）对种子发芽的抑制作用及其生理生化响应. 结果表明：浓度大于70 mg L-1 ABA和大于4 mmol L-1 SA均不同程度地抑制种子发芽并表现剂量效应，赤霉素对二者有拮抗作用，70 mg L-1 ABA＋8.0 mmol L-1 SA对小麦普遍具有强烈的发芽抑制效应；ABA阻抑种子发芽是一种延缓作用，受基因型影响较大；SA对不同基因型有强烈的休眠促进作用，并显著提高种子对ABA的敏感性（P＜0.01）；种子萌发过程中，两种激素均诱导籽粒α-淀粉酶和PPO活性下降，且SA处理组的酶活性降幅更大；ABA明显促进种子PAL活性，而SA处理组的PAL活性水平最低. 因此，ABA与SA的发芽抑制效应与作用方式不同，SA增强种子的ABA敏感性，二者组合产生了良好、稳定的发芽抑制效果.