【作者】 蒲育林；

【导师】 王蒂；

【作者基本信息】 甘肃农业大学 ， 作物遗传育种， 2008， 博士

【摘要】 马铃薯微型薯活力问题的由来及其研究思路在于马铃薯产业化生产发展实际需要的推动,旨在利用、控制种薯活力,以获得高质量的微型薯,达到增产增收的目的。尽管决定种薯活力的因素和构成活力差异的组分及其机制是一个十分复杂的问题,但同一品种、同一批种薯,其活力的变化则主要依据种薯老化、劣变程度而定。在生产实践中,采用何种测定方法,加强种薯质量检验,确定高活力的种薯,保证种薯质量,已成为目前我国马铃薯种业生产中亟待解决的重要问题。本论文以不同重量大小、不同品种的马铃薯微型薯为实验对象,研究了不同贮藏条件、不同贮藏温度、不同贮藏时间以及用不同药剂处理对马铃薯微型薯活力的作用和调控等多种生理因素的影响,同时还对不同重量大小、不同品种微型薯在不同条件贮藏的GA3、IAA、ABA等内源激素与种薯活力变化的规律和机理进行了探讨。主要研究结果如下:1、贮藏时间不同、品种不同对微型薯活力的影响都达到极显著水平。‘大西洋’及‘夏波蒂’微型薯贮藏91天后,两个品种的活力水平都比较低,随着贮藏时间延长,其活力指数不断提高,在183天左右时达到最高峰,然后,随贮藏时间延长其活力指数呈下降趋势。贮藏183天的‘大西洋’、‘夏波蒂’活力指数分别为0.0633、0.0345,分别比贮藏91天的高69.67%、60.87%,比贮藏275天的高71.3%、52.44%;说明适合微型薯的贮藏时间应该是183天,缩短或延长贮藏时间都会降低微型薯活力,此时播种产量最高,也是最佳的播种时间。2、经不同条件贮藏后,‘大西洋’及‘夏波蒂’微型薯活力发生显著变化,两品种活力指数均呈显著差异。其中以冷藏条件贮藏后的活力指数最高,‘大西洋’活力指数为0.0949,分别比窖藏和室温贮藏高20.44%和33.51%;‘夏波蒂’活力指数为0.0784,分别比窖藏和室温贮藏分别高20.28%、35.46%。表明贮藏方式不同、品种不同对微型薯活力的影响极为显著,适合微型薯贮藏条件的顺序是冷藏＞窖藏＞室温贮藏。低温贮藏是适宜微型薯的贮藏方式。3、微型薯重量大小不同,对种薯活力高低有显著的影响作用,活力指数随种薯重量增加而显著提高,种薯越大、活力越高,不同重量大小种薯的活力指数差异程度达到极显著水平。‘大西洋’及‘夏波蒂’7-8g规格的微型薯活力为0.0436和0.0383,分别较6-7g的高0.91%和10.83%,比5-6g的高26.54%和38.79%,比4-5g的高40.28%4和40.41%,比3-4g的高42.05%和48.8%,比2-3g的高69.72%和55.44%,比1-2g的高74.16%和72.43%,比≤1g的高76.71%和76.76%。所以,在购买或种植马铃薯微型薯时,宜选用重量≥2g以上微型薯,以获得高产量和高效益。4、不同品种的微型薯活力指数差异较大,品种不同、产量不同、活力指数差异也显著不同,芽干重、产量与种薯活力之间的相关性最密切,对种薯活力的影响作用最大,这说明,不同品种的微型薯活力不同,品种对种薯活力有显著影响作用,不同品种的微型薯在一定程度上决定着产量的高低。陇薯3号的微型薯活力最大为0.0531,比新大坪高4.9%,比大西洋高15.82%,比费乌瑞它高41.05%,比夏波蒂高69.49%。5、不同药剂浸种处理2h对微型薯发芽的促进作用最大,处理时间越长对微型薯发芽的促进作用越小,甚至处理12h后反而对发芽有显著的抑制作用。PEG、核黄素处理不仅能显著提高微型薯活力,而且对提高微型薯发芽、出苗和幼苗生长有明显的促进作用。PEG2000高浓度、核黄素低浓度、PEG8000低浓度处理对微型薯发芽和出苗有显著的促进作用,促进率分别为73.03%、68.44%和58.89%;GA₃中浓度、PEG8000低浓度、NaCl低浓度、PEG8000中浓度等处理对提高微型薯活力作用最显著,分别较对照提高微型薯活力水平112.73%、100%、76.36%和72.73%。6、不同品种、不同重量大小的微型薯在不同条件贮藏对内源激素含量和种薯活力有显著的影响作用。微型薯GA₃含量比IAA含量高97.97%,比ABA含量高86.73%,而IAA含量仅比ABA含量略高3.8%,说明微型薯内GA₃含量显著高于IAA含量和ABA含量,微型薯IAA含量和ABA含量基本一致。在冷藏、窖藏、室温藏等3种不同条件贮藏后,两个品种的GA₃含量极显著高于IAA、ABA的含量,ABA含量显著高于IAA的含量;两个品种的活力指数在冷藏条件最高,在窖藏条件中等,在室温藏条件最低。由此说明无论贮藏条件如何改变、品种类型如何变换,微型薯GA₃、IAA、ABA内源激素含量之间的比例关系始终是一致的,但不同贮藏条件、不同品种同一种内源激素含量和种薯活力变化趋势的变化趋势有所不同。更多还原

【Abstract】 The vigor of potato minitubers plays a very important role in seed tuber production. Although the factors of determining and affecting the vigor are complex,the main factors should be seeked out so as to find out the methods for detecting and increasing it.Up to now,the reports on minituber vigor and its mechanism as well as the methods for increasing it are very poor.In order to find out the available methods for determining and increasing the vigor,the systematic researches were carried out.Because the minituber vigor determination and increasing are a very urgent need resolving problem,the study results have important theoretical and practical significance.In the studies,the potato minitubers with different weight from different varieties were taken as the testing material to study effects of minituber vigor under different storage conditions,temperature,periods and also the effects of different chemical treatments.Also,the mechanism between endohormones,such as GA₃,IAA,ABA,and minituber vigor changes under different storage conditions were also studied.The main results were as follows:1.Effects of varying storage periods and different varieties on minituber vigor had extremely significant difference.The minituber vigor of ’Atlantic’ and ’Shepody’ after 91 days storage was lower because of just breaking its dormancy,and then,the vigor increased with the lengthening storage time,and the highest vigor was found after 183 day’s storage.Then the vigor decreased.The vigor index of ’Atlantic’ minituber stored for 183 days was 0.0633,69.67%higher than those stored for 91 days and 71.3%higher than those stored for 275 days.The vigor index of ’Shepody’ minitubers was 0.0345, 60.87%and 52.44%higher than those stored for 91 and 275 days respectively.It was indicated that suitable storage time for minitubers should be 183 days.It was the best time to get best yield in the fields.If longer or shorter,it would reduce minituber vigor.2.The minituber vigor of ’Atlantic’ and ’Shepody’ changed greatly after stored under different storage conditions.The index of vigor under cold storage was highest among them.The vigor of ’Atlantic’ was 0.0949,20.44%and 33.51%higher than those under cellar and room storage respectively and that of ’Shepody’ was 0.0784,20.28%and 35.46%higher than those under cellar and room storage respectively.It showed that the advantage order for storage conditions was cold＞cellar＞room.Therefore,the cold storage is the most suitable condition for potato minitubers.3.The effect of minituber weight on the vigor was very significant.The vigor index rised with the weight increasing,ie.the higher the weight,the stronger the vigor.It was indicated that the differences of vigor index among different weight reached extreme significant level.The minituber vigor of ’Atlantic’ with 7-8g weight was 0.0436,and 0.91%,26.54%,40.28%,42.05%,69.72%,74.16%and 76.71%higher than that of the minitubers with 6-7g,5-6g,4-5g,3-4g,2-3g,1-2g,and≤1g respectively;In’Shepody’,it was 0.0383 in 7-8g weight minitubers,and it was 10.83%,38.79%,40.41%,48.8%, 55.44%,72.43%and 76.76%higher than the same weight minitubers in "Atlantic" respectively.Therefore,when purchasing or planting minitubers,if it is possible the bigger ones should be selected in order to gain high yield.4.The vigor differences of minitubers among different varieties were great.Dry sprout weight and yield were closely related with vigor,so that it affected vigor very much.The minituber vigor of Longshu No.3 was 0.0531,it was 4.9%,15.82%,41.05% and 69.49%higher than that of Xingdaping,Atlantic,Favorite and Shepody respectively.5.Seed soaking treatment with different chemicals for 2 hours could improve minituber sprouting,and increase its length,but it was weaker,and could restrain sprouting after 12 hours.PEG,riboflavin treatment could not only improve minituber vigor,but also promote sprouting,emergence and young seedling growth.Soak treatments with PEG2000 in high concentration,riboflavin in low concentration and PEG8000 in low concentration could promote sprouting and emergence,the rate of promotion was 73.03%,68.44%and 58.89%respectively;Soak treatments with GA₃ in medium concentration,PEG8000 in low concentration,NaCl in low concentration or PEG8000 in medium concentration could improve minitubers vigor greatly,which was 112.73%,100%,76.36%and 72.73%higher than that of control.6.Under different storage conditions the content of endohormone and vigor of minitubers with different weight and varieties varied remarkably.The GA₃ content of minitubers was 97.97%higher than IAA,86.73%higher than ABA,but IAA content was only 3.8%higher than ABA.The results showed that the content of GA₃ was much higher than that of IAA or ABA but IAA content was almost the same as ABA content. Under cold,cellar and room storage conditions,GA₃ content of the two varieties all were much higher than IAA,ABA content,and ABA was much higher than IAA;The vigor index of the two varieties was highest under cold storage condition,medium under cellar condition and low under room condition.Aslo it could be seen that the proportion of GA₃, IAA and ABA was almost unchanged in different varieties and under different storage condition,but in the same endohormone,the content and the changing trend of minituber seed vigor were not alike.更多还原