【作者】 崔秀辉；

【导师】 程须珍；

【作者基本信息】 中国农业科学院 ， 种植， 2006， 硕士

【摘要】 杂种优势是生物界的一种普遍现象，只要两个遗传性不同的品种进行杂交，其杂种一代在产量、品质、抗性等方面都有超亲现象。植物常规杂种优势育种主要是玉米自交系育种和农作物雄性不育育种，而在农作物雄性不育育种途径中，除了传统的三系法和两系法外，目前还采用化学杂交剂诱导雄性不育方法，这种方法简单、快捷，是作物杂种优势利用的一条捷径。目前，有关黍杂种优势利用方面研究未见报道，至今仍未发现雄性不育系，显然，用遗传方法来实现黍杂种优势利用希望很渺茫。受化学杂交剂在水稻、小麦、油菜等作物上成功应用的启示，本研究借助优秀的小麦化学杂交剂SQ-1诱导黍雄性不育，并对其诱导效果进行分析评价，目的是利用化学杂交剂在黍杂种优势利用方面进行尝试，为今后这方面研究进行探索性试验；另一方面将化学杂交剂作为常规育种去雄的工具，提高去雄工作效率，加大杂交组合，加速新品种选育。本研究采用裂区试验设计方法，分两部分研究了化学杂交剂SQ-1的应用效果。第一部分是药效试验，以喷药时期为主区，喷药剂量为副区，用SQ-1诱导产生的雄性不育率、杂交率及自然授粉结实率3项指标评价应用效果。结果表明：喷药时期、喷药剂量及时期与剂量一级互作显著或极显著地影响不育率和杂交率。在雌雄蕊原基分化期，喷药剂量在4.0kg／hm~2和5.0kg／hm~2时诱导雄性不育率、杂交率都在95％以上；花粉粒形成初期，喷药剂量为5.0kg／hm~2时诱导雄性不育率和杂交率在95％以上。喷药时期对自然授粉结实率影响不显著，剂量及时期与剂量一级互作影响显著，自然授粉结实率随着剂量的增加呈现降低趋势。综合不育率、杂交率和自然授粉结实率三项指标，并考虑制种成本，最终确定SQ-1在黍上应用的最佳时期为雌雄蕊原基分化期，最适剂量为4.0kg／hm~2。第二部分以4.0kg／hm~2和5.0kg／hm~2两个喷药剂量为主区，10个黍品种(系)为副区，进行SQ-1与不同基因型品种(系)互作效应试验。结果表明：4.0kg／hm~2和5.0kg／hm~2两个喷药剂量诱导雄性不育率在95％以上，变化幅度为97.9％～100％，SQ-1与参试不同基因型品种之间无明显的互作效应，诱导黍雄性不育具有广普性，而且在适宜剂量下可诱导产生接近100％的不育率。自然授粉结实率和人工饱和授粉结实率随着喷药剂量增加而降低；不同品种(系)对药剂反映不同，在同一个剂量下自然授粉结实率和人工饱和授粉结实率变化幅度很大。通过田间调查和观察，SQ-1对参试品种生长发育及植株外部形态影响不大，处理区株高、穗长、抽穗期与对照无明显差异，株高平均降低1.33cm，穗长缩短2.08cm，抽穗期平均推迟0.7天，说明SQ-1对黍副作用小。更多还原

【Abstract】 Heterosis is a common phenomenon in nature. The cross between two varieties that have different genetic backgrounds will generate an individual of hyper-parent in yield, quality and resistance. The conventional breeding using heterosis is to use inbred line in maize and male sterility in other crops. Except for the conventional methods by using three-line system or two-line system in male-sterility breeding, the male sterility induced by chemical hybridizing agent is also accepted as a simple and rapid method for heterosis breeding now. There were no reports on the utilization of heterosis in proso and no male sterility line of this crop was found yet. Thus, it is difficult to use heterosis in proso by using conventional genetic method. According to the successful utilization of chemical hybridizing agent in rice, wheat, rape and other crops, we selected the chemical agent SQ-1 that had been used in wheat to induce male sterility of proso and evaluated the induction effect in this study. The main aims are to provide useful information on utilization of male sterility induced by chemical hybridizing agent in common mille, to increase the castration efficiency by using the chemical hybridizing agent, to broaden the cross combination and to accelerate the development of new variety.The split-plot design was used to study the effect of SQ-1 in this study. And the whole experiment was divided into two parts. The first part was to evaluate the effect of SQ-1, in which different growing stages treated by SQ-1 were designed as main plot and different dosages of SQ-1 was as sub plot. The effect of male sterility induced by SQ-1 was evaluated by three indice: male sterile rate, crossing rate and fruit setting rate of natural pollination. The results showed that male sterile rate and crossing rate were both significantly or extremely significantly affected by growing stages, dosages and the interaction between the two factors. These two rates were both over 95% when proso was treated by SQ-1 with dosage of 4.0 kg/hm~2, 5.0 kg/hm~2 during the differentiation of pistil and stamen. And they were also both over 95% when proso was treated by SQ-1 with the dosage of 5.0 kg/hm~2 in the period of primary formation of microspore. The fruit setting rate of natural pollination was not significantly different among varied stages treated by SQ-1, but it was significant affected by dosages and the interaction between stages and dosages. And the fruit setting rate of natural pollination decreased with the dosage being increased. Considering all the three evaluation indices and the cost of production for hybrid seed, the optimal stage treated by SQ-1 in proso was deemed as the differentiation period of pistil and stamen with the optimal dosage was 4.0 kg/hm~2.The second part was to study the effect of interactions between SQ-1 and different genotypes of proso. In this part, different dosages of SQ-1 were designed as main plots and different varieties were as sub plots. The results showed that the male sterility rate was over 95% at dosages of 4.0 kg/hm~2 and 5.0 kg/hm~2, with the variation from 97.9% to 100%. There is no significant effect between SQ-1 and varieties of different genetic background. The male sterility in proso induce by SQ-1 has a wide range of use, and the sterility rate at proper dosage can reach to 100%. The fruit setting rate of natural pollination and artificial saturation pollination both decreased, when the dosage of SQ-1 increased. Different reactions at the same dosage of SQ-1 were found in diverse varieties, and the fruit setting rate of natural pollination fertility and artificial saturation pollination both varied greatly among varieties. According to the observation in the field, SQ-1 has little effect on growth and phenotypes of proso. Although an average of 1.33 cm was decreased in plant height, 2.08 cm was shortened in ear length and 0.7 d was deferred in ear sprouting period, there were no significant differences in plant height, ear length and ear sprouting period between the treated plots and the contrast, this indicated that there was little side effect of SQ-1 on proso.更多还原