花粉直感对杨梅果实品质及不同蔗糖代谢酶活性的影响

Effect of xenia on fruit quality and sucrose metabolism enzyme activity in red bayberry

【目的】探究杨梅的花粉直感效应。【方法】以‘东魁’‘荸荠种’为母本,选用黄岩、舟山的雄株作为花粉源进行人工授粉,并以自然授粉为对照,观察其对当年果实品质的影响,并且测定2个不同发育时期的杨梅果实蔗糖磷酸合成酶(SPS)和蔗糖合成酶(SS)的活性。【结果】以‘荸荠种’为母本的授粉组合中,单果质量比对照低6.5%~18.6%,果实纵径比对照低4.62%~9.16%,亮度比对照低5.1%~16.4%,总糖含量比对照低14.17%~16.67%,维生素C含量比对照低6.73%~10.3%,可滴定酸含量比对照高17.1%~20.3%。以‘东魁’为母本授粉组合中,与自然授粉相比,果实质量、果实横纵经、可食率等方面差异不显著,色差比对照低8.1%~9.3%,‘东魁’×黄岩花粉可溶性固形物含量、总糖含量和可滴定酸含量分别比对照高31.95%、3.06%、25.39%。杨梅人工授粉不同雌雄组合表现出花粉直感现象。SPS活性在5月19日和6月19日最高的分别是‘荸荠种’×舟山花粉和‘东魁’×舟山花粉。SS活性在5月19日和6月19日最高的分别是‘荸荠种’×黄岩花粉和‘东魁’×黄岩花粉。【结论】‘荸荠种’×舟山花粉、‘东魁’×黄岩花粉为最佳组合,‘荸荠种’和‘东魁’都与黄岩和舟山的杨梅花粉有亲和力。从容易取材及品质改良两方面综合考虑,黄岩和舟山的杨梅雄株在品质改良中有着一定的优势,舟山的杨梅花粉为‘荸荠种’授粉对品质的改良更好,黄岩的杨梅花粉为‘东魁’授粉对品质的改良更佳。

[Objective] Xenia is a phenomenon that pollen source influences fruit traits, including color, size, soluble solids, seed size and so on. In this study, we evaluated different pollination combinations in improving fruit quality. [ Methods ] Pollens from different parent cuhivars were collected from Huangyan and Zhoushan counties in Zhejiang province before the male flowers opened and stored under -20 ℃. Female flowers were selected from 15-year-old trees of Myrica rubra ＇Biqizhong＇ and ＇Dongkui＇ in Haining county, Zhejiang province. The pollination combinations included natural pollination of ＇Biqizhong＇ （CK1）, ＇Biqizhong＇ x Huangyan（BH）, ＇Biqizhong＇ x Zhoushan （BZ）, natural pollination of ＇Dongkui＇ （CK2）, ＇ Dongkui＇ x Huangyan （DH）, ＇ Dongkui＇ x Zhoushan （DZ）. The fruit weight, size, color, hardness, TSS, total sugars, titratable acids, and vitamin C were tested. Fruit weight was measured using a balance, size with a caliper, color parameters detected with a spectral photometer （HITACHI307）, hardness using a texture analyzer and TSS with a saccharimeter. The contents of total sugars, titratable acids, and vitamin C were determined with alkaline acid solution method, sodium hydroxide solution method, and 2, 6-dichlo- rine indophenol solution, respeetively. Sucrose phosphate synthase （SPS） and sucrose synthase （SS） cata- lyze the synthesis of sucrose in plants. The aetivities of both enzymes on May 19 and Jun 19 were determined to understand sucrose synthesis in bayberry trees. Data collected were analyzed with SPSS 17.0 to do analysis of variation and multiple comparison for significance of difference. [ Results ] The fruit weight, size, appearance, hardness and color had significant differences among different pollination combinations. The fruit weight in BH and BZ was lower than in CK1 by 6.5% and 18.6%, respectively. BZ had the heavi- est fruit mass （7.9 g） among the artificial pollination combinations. The fruit transverse and longitudinal di- ameters in BH were 4.3% and 7.6% smaller than those in CK1, respectively, and those in BZ were shorter by 4.62% and 9.16%, respectively. However, fruit weight, and transverse and longitudinal diameters in pollination combinations with ＇Dongkui＇ had no significant difference compared with CK2. The flesh re- covery had no significant difference among all the pollination combinations with both female parent culti- vars. The hardness of BZ and BH fruit was significantly higher than that of CK1 by 7.81% and 18.47%, re- spectively. The fruit hardness in DH and DZ was also higher than that in CK2. The fruit brightness in BH and BZ was significantly lower than that in CK1 by 5.1% and 16.4%, respectively, and the yellow index in BH and BZ was 6.43% and 20.30% lower, respectively. The red index of BZ fruit was the highest among the six combinations, being 4.8% higher than CK1. The fruit brightness in DH was significantly and 5.75% lower than that in CK2, but that in DZ significantly and 5.87% higher. However, the yellow index of ＇Dongkui＇ fruit produced from different pollen sources was significantly different with that of CK2 fruit, but red index had no difference. The content of soluble solids was different in different pollination combinations. Soluble solids in BH and DZ fruits were 0.17% and 3.24% lower than the controls, respec- tively, but those of BZ and DH fruits were significantly higher than that of the control by 7.14% and 31.95%, respectively. The total soluble sugars in all the cross pollination combinations were lower than in the controls, but the content titratable acids was higher. The vitamin C in the fruits generated from cross pollination combinations with ＇Biqizhong＇ as the female parent was lower than that in CK1, but that in the fruits from the pollination combinations with ＇Dongkui＇ was higher than that in CK2. The contents of soluble sugars in BH and BZ were 14.17% and 16.67% lower than that in CK1, but DH had a significant- ly （3.06%） higher content of soluble sugars than CK2. The titratable acids in BH and BZ fruit were 20.30% and 16.99% higher than that in CK1, respectively. In addition, the titratable acids in DH dramati- cally increased by 25.39% compared with CK2, but those in DZ decreased by 2.73%. The contents of vita- min C in BH and BZ were 10.3% and 6.73% lower than those in CK1, respectively. However, the content of vitamin C in DH and DZ was higher than that in CK2, with that in DZ being 8.63% higher than that in CK2. The SPS activity in the six pollination combinations on May 19 and June 19 were measured. The re- suits indicated that SPS activities in all pollination combinations on June 19 were higher than those on May 19. The enzyme activity in BZ and DZ increased greatly. SPS activity in BH and BZ on May 19 in- creased by 82.55% and 87.06% compared with CK1, respectively, and that on June 19 increased by 28.8% and 37.08%, respectively. SPS activity in BZ was 47.7 mg. g i （expressd by the sucrose content） on May 19 and 57.75 rag. g-~ on June 19. In DH and DZ, the enzyme activity was increased by 28.20% and 35.33% respectively on May 19, and by 31.62% and 44.77% respectively on June 19, compared with CK2. SPS activity in DZ was 41.75 mg·g^-1 and 58.24 mg·g^-1 on May 19 and June 19, respectively, which was higher than that in DH. The SS activity in BH and BZ was higher than in CK1, being 99.81% and 115.89% higher on May 19 and 76.49% and 105.98% higher on June 19, respectively. The enzyme activity in BH was 77.71 mg·g^-1 on May 19 and 66.86 mg·g^-1 on June 19, which was the highest among all the pollination combinations. The SS activity in DH was 52.14 mg·g^-1 and 66.64 mg·g^-1 on May 19 and June 19, respectively, which was higher than that in CK2. However, the enzyme activity in DZ on Mayl9 waslower than that in CK2. [Conclusion] ＇Biqizhong＇ and ＇Dongkui＇ displayed a high pollination compati- bility with the cultivars in Huangyan county and Zhoushan county. The fruit weight, transverse and longitudinal diameters and SS activity in DH were the highest among the six pollination combinations. However, the fruit hardness, TSS and SPS activity in BZ were higher compared with those of the other treatments. It was clear that the quality of DH and BZ fruit had improved greatly and that pollen source significantly influenced the quality of fruit. The results provided information for pollination combination selection to improve fruit quality via artificial pollination. The results showed that the male plants in Zhoushan had a better effect in improving quality of ＇ Biqizhong＇, while those in Huangyan seemed better for ＇ Dongkui＇.