自花授粉花柱提取物对澳洲坚果品种间杂交亲和性的影响

Effects of self-pollination style extracts on the crossing-compatibility among Macadamia varieties

【目的】明确澳洲坚果品种间杂交的亲和性,为快速鉴定品种间杂交亲和程度和授粉品种配置提供理论依据和实践支撑。【方法】以澳洲坚果13个品种为母本试材,10个品种为父本试材,设置115个杂交组合,利用母本自交花柱提取液培养基培养父本花粉,测定杂交组合的花粉萌发率及花粉管生长情况,结合花粉萌发受影响程度指数(pollen germination,PG)与花粉管生长受影响程度指数(pollen tube growth,PTG),判定品种间杂交亲和性程度。【结果】明确了115个杂交组合的亲和性程度,筛选出54个强杂交亲和性组合,其中有9对杂交组合可互为亲本;另外筛选出28个中等杂交亲和性组合和33个弱杂交亲和性组合。品种HAES863、O.C、HAES820可以作为杂交育种父本材料,在果园构建中可以作为13个参试母本的授粉树;品种HAES863、D4、HAES951、HAES816、HAES842为极好的杂交育种母本材料。【结论】建立了澳洲坚果品种间杂交亲和性室内鉴定标准,将杂交亲和性划分为强(PG值≤0.5,PTG值≤0.2)、中(0.5<PG值≤0.7;0.2<PTG值≤0.4)和弱(0.7<PG值<1;0.4<PTG值<1)3种类型,用于澳洲坚果杂交亲和性的快速鉴定,为澳洲坚果种植园品种配置提供参考。

【Objective】This study aimed to clarify the crossing-compatibility among Macadamia varieties and provide a theoretical and practical basis for arranging pollination varieties.【Methods】Thirteen and ten Macadamia varieties were respectively used as female and male parent materials for a total of 115 crossing combinations.The male pollenes were cultured the media containing self-pollination style extracts of the female parents,and the pollen germination rate(PGR)and pollen tube length(PTL)were determined for each combination.The strength of crossing-compatibility of the crossing combination was divided into three categories(strong,medium and low)by a combined evaluation with their pollen germination rate,pollen tube length,index of influence degree ofmacadamiapollen germination(PG)and index of influence degree of Macadamia pollen tube growth(PTG).【Results】(1)The crossingcompatibility was low between the variety HY and the 12 tested female parents,indicating that these combinations were not suitable for the field experiments.(2)The crossing-compatibility between the variety A16 and the respective variety of A4,O.C,D,HAES951 and HAES816 was strong,indicating that these combinations could be used for further field hybridization test.(3)Among the 11 crossing combinations with the variety A4,the crossing-compatibility of the 9 combinations was strong,and the cross ing-compatibility of the 2 combinations was medium, indicating that the variety A4 could be used as amale parent in cross breeding. (4) The variety HAES695, having a strong cross-compatibility with thefemale parent HY, and a moderate crossing- compatibility with the varieties of O.C and D4, could beused for cross breeding. It also might be incompatibile with the varieties HAES815 and HAES863. (5)The variety HAES816 had strong crossing-compatibility with the variety D4, O.C and HAES951, indicatingthat such a combination could also be used for cross breeding. (6) In general, the varietyHAES863, which had the highest pollen germination rate and the fastest pollen tube growth under all12 growth media, could be used as a male parent for all of the tested varieties. (7) The varietyHAES820, with strong crossing-compatibility in 11 of the 12 crossing combinations, except for a mediumcrossing- compatibility with the variety HY, could be used as a male parent. (8) The varietyHAES951 could be pollinated with the variety of HAES816, HAES863, D4 and HAES842 respectively,but not with the variety O.C. (9) The variety D could be matched with the variety HAES863 orHAES816 for a pollination test, and would be a good material for studying pollen tube polar growth ofmacadamia as it had a greater pollen germination rate and also a faster pollen tube length than any ofthe other male parents. (10) The variety O.C, with a greater pollen germination rate and a rapid pollentube growth under all the growth media tested, could be used as a pollination tree for the 13 tested femaleparents. (11) Among the 115 crossing combinations, the interval of index of influence degree ofMacadamia pollen germination (PG) was -1.31-0.87, and the interval of index of influence degree ofMacadamia pollen tube growth (PTG) was -0.64-0.62. The larger values of the PG and PTG the varietieshad, the weaker the crossing-compatibility between the varieties they had;the smaller values of thePG and PTG the varieties had, the stronger crossing-compatibility between the varieties they had. Macadamiawas gametophytically self-incompatible, and the pollen germination was lightly affected by theself-pollination style extract from the female parents, so the growth of pollen tube was taken as an importantindicator for determining the crossing-compatibility between the varieties, and the PG was takenas the auxiliary index. The PTG values would be analyzed firstly, when PTG<0, we would not considerthe PG values and the combination would be considered as strong crossing- compatibility;anotherstander was that if PTG>0.4, the PG was also not necessary to consider and the combination was thesame as the weak crossing-compatibility directly. When the PG and PTG were be comprehensively analyzedat the same time, we found that the crossing- compatibility between the macadamia varietieswould be obtained more accurately. At the last, according to the pollen germination rate, pollen tubelength, index of influence degree of the pollen germination and index of influence degree of the pollentube growth, the crossing- compatibility of the 115 crossing combinations were divided into 3 types,that is, strong (PG≤0.5;PTG≤0.2), medium (0.5<PG≤0.7;0.2<PTG<0.4 ), and low (0.7≤PG<1;0.4≤PTG<1).【Conclusion】The crossing-compatibility among macadamia varieties was divided intostrong, medium and low category according to their values in the index of influence degree of the pollengermination (PG) and the index of influence degree of the pollen tube growth (PTG). Among the115 combinations, 54 combinations had a strong crossing- compatibility. The variety HAES863, O.Cand HAES820 could be used as a male parent in cross breeding and also a pollination tree for the 13tested female varieties. The variety HAES863, D4, HAES951, HAES816 and HAES842 could be usedas excellent female parent materials in cross breeding.