A study on the pollination compatibility of different cultivars of Prunus salicina×armeniaca with different pollenizers

Abstract: 【Objective】The study investigated pollination compatibility of different cultivars of Prunus salicina×armeniaca with different pollen sources in order to select suitable pollinizer varieties and to providereference for reasonable arrangement of pollinizers for cultivation.【Methods】Three cultivars of P. salicina×armeniaca were used as female parents, and one cultivar of Chinese plum, one cultivar of P. domestica L. and two cultivars of apricot as male parent. The pollen quantity and pollen viability of the tested cultivars were examined before cross pollinations were carried out and fruit set in the three cultivars of P. salicina×armeniaca after self-pollination, cross-pollination with the pollens of the above-mentioned parentsand open pollination was recorded. At 6, 8, 10, 12, 24, 48, 72, 96, 120 and 144 h after pollination, pollentube growth in the FAA-fixed styles was observed, and the compatibility of different pollination combina⁃tions was compared.【Results】The average pollen quantity in a single flower of all the tested cultivars was1 120 000 grains per flower and that the average pollen viability was 31.9%. The highest pollen quantityper flower was found in‘Saimaiti’with 2 810 000 grains per flower and the lowest was in‘Nüshen’withonly 370 000 grains per flower. Among the three cultivars of P. salicina×armeniaca,‘Konglongdan’hadthe largest pollen quantity (960 000 grains per flower), while‘Fengweihuanghou’had the fewest (560 000grains per flower). However, pollen viability of‘Fengweihuanghou’was the highest (65.1%), and that of‘Weidi’was the lowest with only 3.3%. Self-pollination in the three cultivars of P. salicina×armeniacagenerated an extremely low fruit set, which was 0 in‘Fengweihuanghou’and‘Weidi’2.16% in‘Konglongdan’. Therefore, the three cultivars of P. salicina × armeniaca were self-incompatible. There weresome differences in fruit set among different pollination combinations. Open pollination of‘Fengweihuanghou’produced a fruit set rate of 6.72%. Fruit set rate in‘Fengweihuanghou’בKonglongdan’and‘Fengweihuanghou’בMeilili’was 3.33% and 2.62%, respectively, and it was 0 in the cases of‘Fengweihuang⁃hou’בWeidi’and‘Fengweihuanghou’בNüshen’. The fruit set rate in open pollination of‘Konglong⁃dan’was 8.52%, which was the highest among the three cultivars of P. salicina×armeniaca. Fruit set ratein‘Konglongdan’בMeilili’,‘Konglongdan’בNüshen’and‘Konglongdan’בJianali’was 8.87%,13.86% and 0.41%, respectively. Open pollination in‘Weidi’generated a fruit set rate of 4.31%, and thefruit set rate in‘Weidi’בKonglongdan’,‘Weidi’בMeilii’and‘Weidi’בJianali’was 7.28%, 6.25%and 1.38%, respectively. In the pistils of the three cultivars of P. salicina×armeniaca as the female parent,the pollens from different parents began to germinate 10 h after pollination, and the pollen tubes of somecultivars reached the base of the style 120 h after pollination. There were differences in processes of pol⁃len germination and pollen tube growth among different cultivars. The pollen tube of some cultivars neverreached the base of style. Some of the pollen tubes in the case of‘Fengweihuanghou’בKonglongdan’had grown to the base of the style 72 h after pollination, and the ratio of the pollen tubes that reached thebase of the style 96 h after pollination was 80%, but the pollen tubes in the case of‘Fengweihuanghou’בWeidi’and‘Fengweihuanghou’בJianali’failed to reach the base of the style. The pollen tubes in‘Konglongdan’בSaimaiti’had reached the base of the style 48 h after pollination, and the ratio of thepollen tubes in‘Konglongdan’בNüshen’reached the base of the style 72 h after pollination was 60%,but those in the cases of‘Konglongdan’בWeidi’and‘Konglongdan’בMeilili’never reached the baseof the style. The pollen tubes in‘Weidi’בFengweihuanghou’,‘Weidi’בJianali’and‘Weidi’בSaimaiti’grew vigorously and entered the base of the style 72 h after pollination, with a percentage ofthe pollen tubes entered the ovule 144 h after pollination of 100%. However, the pollen tube of‘Weidi’בMeilili’and‘Weidi’בNüshen’failed to reach the base of style.【Conclusion】The pollen of‘Konglong⁃dan’is more highly compatible with‘Fengweihuanghou’than the other pollen sources studied. Both ofthem and‘Saimaiti’are suitable pollinizers for‘Weidi’. The pollination compatibility between‘Fengweihuanghou’and two cultivars of apricot is weak.‘Meilili’and‘Nüshen’are suitable as the pollen suppli⁃ers for‘Fengweihuanghou’and‘Konglongdan’, but not suitable‘Weidi’. The pollen viability of‘Wei⁃di’is very low with poor compatibility with P. salicina×armeniaca cultivars, and therefore it is not a suitable pollinizer.