In pepper haploid breeding, the low natural doubling rate is a major bottleneck. Artificially inducing haploids chromosome doubling can obtain pepper diploids and improve haploid breeding efficiency. While there is no effective way reported in pepper up to now. This study aimed to investigate the relationship between pepper microsporogenesis and flower development to guide diploid induction and also explore suitable conditions for treatments using chemical reagents and high temperature. The results showed that flower buds developed to stage 2 was most suitable for chemical and high-temperature treatment, when the corolla and anther were green, and the corolla slightly exposed the bracts, and the meiosis were in the zygotene–diplotene phase; the highest induction rate reached 30% when growth points of pepper haploids were treated with 0.006% pendimethalin for 2 days, which is higher than the traditional method of colchicine treatment; the highest induction rate for high-temperature treatment was 14.29%, when the flower buds were subjected to high-temperature treatment at 38 °C for 2 h. The study first report that high-temperature treatment is a feasible method for chromosome doubling of pepper haploids and provide an efficient and practical chemical treatment method for pepper chromosome doubling.

在辣椒单倍体育种中，自然倍增率低是一大瓶颈。人工诱导单倍体染色体加倍可以获得辣椒二倍体，提高单倍体育种效率。而目前在辣椒中还没有报道有效的方法。本研究旨在研究辣椒小孢子发生与花发育之间的关系，以指导二倍体诱导，并探索使用化学试剂和高温处理的合适条件。结果表明，发育至第2期的花蕾最适合化学处理和高温处理，此时花冠和花药呈绿色，花冠稍显露苞片，减数分裂处于合子-二线期；辣椒单倍体生长点经 0 处理后诱导率最高可达 30%。006%二甲戊灵2天，高于传统秋水仙碱处理方法；花芽在38℃高温处理2h时，高温处理的最高诱导率为14.29%。该研究首次报道高温处理是辣椒单倍体染色体加倍的可行方法，为辣椒染色体加倍提供了一种高效实用的化学处理方法。