增施钾肥、磷肥及稀土微肥对马铃薯抗旱性的影响及机制研究

发布时间：2019-06-27 20:59

【摘要】：钾肥、磷肥是作物生长发育必不可少、但在旱区土壤中含量较少的矿质肥料,其对作物的作用除了供应直接营养外,合理施用还能大大增强作物的抗旱性。稀土微肥作为一种新型肥料,对增强植物的抗旱性有一定的作用。在我国北方特别是西北地区的主要耕作地以旱地为主,因此,水分条件成为制约农业生产和发展过程中不可忽略的问题。关于施肥前人的研究主要集中在氮磷钾混合肥料对马铃薯产量和品质的影响,但关于不同钾肥、磷肥及稀土微肥的供给量是如何调控马铃薯抗旱的生理机制,特别是单一肥料对马铃薯抗旱增产所需最佳施肥水平方面研究显著不足,值得系统深入开展相关研究。本文以“大西洋”马铃薯为材料,控制土壤含水量及钾肥、磷肥及稀土微肥的不同增施量,通过对其苗期抗性生理指标、成熟期农艺性状指标的测定,旨在探究不同增施量的钾肥、磷肥及稀土微肥对马铃薯生长发育和抗旱生理的影响,揭示增施适量钾肥、磷肥及稀土微肥提高马铃薯抗旱性的生理机制,为马铃薯在干旱区种植和推广提供理论指导。主要结论如下:1.水分亏缺是造成马铃薯生长发育迟缓的主要因素之一。本文通过设定Water-CK,Water-1,Water-2三个土壤水分含量,通过测定马铃薯幼苗叶片光合色素含量、渗透调节物质含量以及抗氧化酶活性等生理指标,研究发现随着干旱胁迫程度的增加,马铃薯幼苗叶片含水量和叶绿素含量逐渐下降,可溶性糖、脯氨酸等渗透调节物质以及丙二醛(MDA)含量、相对电导率(REC)及超氧阴离子(O_2~-.)产生速率逐渐升高,抗氧化酶活性增强,株高、茎粗、根长、匍匐茎数、地上部分干重等生物量逐渐降低,马铃薯单株薯重及块茎中淀粉含量、蛋白质含量和维生素含量下降明显,其中变化最显著的是Water-2下的马铃薯单株薯重,与Water-CK相比较,由最初的623 g降低为423 g,降低了43.6%。说明干旱胁迫对马铃薯最直接的影响是导致其产量的降低。2.叶面增施钾肥后,较未增施的马铃薯幼苗叶片的叶绿素和类胡萝卜素含量显著增加,渗透调节物质大量积累,抗氧化酶活性增强,MDA含量下降,马铃薯株高、基径、地上部分重、根重、根长和块茎重量显著增加;通过叶面喷施不同量的硫酸钾,结果显示每株以3.5g硫酸钾的增施量对促进干旱胁迫下马铃薯生长发育和抗旱性的作用最为显著。说明通过叶面喷施方式增施适宜浓度的硫酸钾可以增强马铃薯植株对干旱胁迫的抗性,增加光合产物的积累,缓解干旱胁迫对马铃薯植株造成的伤害,为马铃薯植株的正常生长提供一个相对良好的环境,从而达到增产增收的经济效益并改善其块茎的营养品质。3.不同水分条件下增施适量磷肥后,显著增加了马铃薯叶片含水量、叶绿素含量,相对增强了抗氧化酶活性,降低了相对电导率、MDA含量和活性氧水平,且马铃薯块茎重量及块茎淀粉、蛋白质和Vc含量显著增加。通过比较包括对照在内的6种磷肥增施量,以每亩增施10.2 kg磷肥对马铃薯幼苗抗旱性及生长发育的促进效果最佳。综上所述,干旱胁迫显著抑制了马铃薯幼苗生长发育,而增施适量磷肥可通过提高渗透调节物质含量和抗氧化酶活性,有效缓解干旱胁迫下马铃薯幼苗叶片的脂质过氧化程度及细胞膜损伤,减轻干旱对生长发育的抑制,从而整体上增强了马铃薯植株耐旱能力。4.通过不同程度干旱胁迫下分别浇灌0、30、60、90、120和150 mg/L PrCl3水溶液发现,增施不同浓度PrCl3后,有效提高了不同水分条件下马铃薯幼苗叶片叶绿素及渗透调节物质含量,降低活性氧代谢物质产生速率,大大增强了抗氧化酶的活性。在Water-2处理下,增施浓度为90 mg/L的PrCl_3溶液时,马铃薯叶片叶绿素、可溶性糖及脯氨酸含量分别较未增施处理提高了162.35%、59.59%、154.45%,MDA含量、O_2~-.产生速率及相对电导率分别降低了67.70%、25.29%、37.70%,抗氧化酶活性提高了38.35%、28.08%、66.00%,成熟期马铃薯株高、茎粗、地上及地下部分干重、地上分枝数、单株薯重分别增加了67.87%、21.68%、32.81%、49.05%、187.50%和63.91%。说明干旱胁迫下增施适量氯化镨可提高幼苗植株细胞内渗透调节物质,增强抗氧化酶活性,减少自由基的积累,缓解干旱胁迫对马铃薯幼苗生长发育造成的损伤,提高马铃薯植株的耐旱能力,为马铃薯在干旱胁迫下的稳产提供保障。综上所述,合理有效的施肥措施及施肥量不仅保证了马铃薯生长发育所需的养分供应,还增加了马铃薯幼苗叶片对碳素的同化累积,显著提高了渗透调节物质含量及抗氧化酶活性,减轻了干旱对马铃薯植株造成胁迫危害,确保植株正常生长发育,从而增强干旱胁迫下马铃薯植株的抗性,提高马铃薯块茎的产量并改善块茎的营养与品质。
[Abstract]:The potash fertilizer and the phosphate fertilizer are essential for the growth and development of the crops, but the mineral fertilizer with less content in the soil of the dry area, the effect of the fertilizer on the crops can greatly enhance the drought resistance of the crops in addition to the direct nutrition supply. As a new type of fertilizer, the rare-earth micro-fertilizer has a certain effect on the drought resistance of the plant. In the northern part of China, especially in the northwest area, the main cultivation is mainly dry land, so the water condition becomes a problem that is not negligible in the process of agricultural production and development. The research on the application of nitrogen and phosphorus was mainly focused on the effect of the mixed fertilizer on the yield and quality of the potato, but the supply amount of the fertilizer, the phosphate fertilizer and the rare-earth micro-fertilizer was the physiological mechanism for controlling the drought resistance of the potato. In particular, that research on the optimal application level of the single-fertilizer to the drought-resistant and yield-increasing yield of the potato is obviously insufficient, and the relevant research is worthy of being carried out in the system. In this paper, by using the "Atlantic" potato as the material, the water content of the soil and the different increasing amounts of the potassium fertilizer, the phosphate fertilizer and the rare earth micro-fertilizer are controlled, the physiological indexes of the resistance to the seedling stage of the soil and the determination of the agronomic characters of the mature period are determined, and the purpose of the invention is to explore the different application amount of the potassium fertilizer, The effect of phosphate fertilizer and rare-earth micro-fertilizer on the growth and drought-resistance of the potato was studied. The physiological mechanism of increasing the drought resistance of the potato was revealed by the application of a proper amount of potassium fertilizer, phosphate fertilizer and rare-earth micro-fertilizer, which provided the theoretical guidance for the planting and promotion of the potato in the arid area. The main conclusions are as follows:1. Water deficit is one of the main factors in the growth retardation of potato. In this paper, by setting the water content of water-CK, Water-1 and Water-2, the content of photosynthetic pigment, the content of osmotic regulating substance and the activity of antioxidant enzymes were determined by the determination of the content of photosynthetic pigment, the content of osmotic regulating substance and the activity of antioxidant enzymes, and the results showed that with the increase of drought stress, The water content and the content of chlorophyll, soluble sugar and proline, and the content of malondialdehyde (MDA), relative conductivity (REC) and superoxide anion (O _ 2 ~-) of potato seedling leaves were decreased. ) the production rate is gradually increased, the activity of the anti-oxidation enzyme is enhanced, the plant height, the stem length, the root length, the number of the stolon, the dry weight of the ground part and the like are gradually reduced, the content of the starch, the protein content and the vitamin content in the potato weight and the tuber of the potato are obviously reduced, The most significant variation is the potato weight of the potato under the Water-2, compared with the Water-CK, reduced to 423 g by the original 623 g and a decrease of 43.6%. The most direct effect of drought stress on potato is the reduction of its yield. after the application of the potassium fertilizer on the leaves, the content of the chlorophyll and the carotenoid in the leaves of the unincreased potato seedlings is obviously increased, the osmotic adjustment substances are accumulated in a large amount, the activity of the anti-oxidation enzyme is enhanced, the content of the MDA is reduced, the potato strain is high, the base diameter, the ground part is heavy and the root is heavy, The root length and the weight of tuber were significantly increased; by spraying different amounts of potassium sulfate on the leaves, the results showed that the effect of increasing the amount of potassium sulfate on the growth and drought resistance of the potato under drought stress was the most significant. The method can enhance the resistance of the potato plants to the drought stress, increase the accumulation of the tomato products, relieve the damage caused by the drought stress on the potato plants, and provide a relatively good environment for the normal growth of the potato plants, So as to achieve the economic benefit of increasing the income and improve the nutrition quality of the tuber. after the appropriate amount of phosphate fertilizer is added under different water conditions, the water content and the chlorophyll content of the potato leaves are obviously increased, the anti-oxidation enzyme activity is relatively enhanced, the relative conductivity, the MDA content and the active oxygen level are reduced, the weight of the potato tubers and the tuber starch are reduced, The protein and the vitamin c content are significantly increased. The drought resistance and the growth and development of the potato seedlings were optimized by comparing the application amount of 6 kinds of phosphate fertilizer, including the control, with the increase of 10.2 kg of phosphate fertilizer per mu. in conclusion, that drought stress obviously inhibit the growth and development of the potato seedling, and the application of the appropriate amount of the phosphate fertilizer can effectively relieve the lipid peroxidation degree and the cell membrane damage of the potato seedling leaf under the drought stress by increasing the content of the osmotic adjustment substance and the antioxidant enzyme activity, The inhibition of the drought on the growth and development is reduced, and the drought resistance of the potato plants is greatly enhanced. in that method,0,30,60,90,120 and 150 mg/ L PrCl3 aqueous solution are separately cast under different degree of drought stress, and after different concentration of PrCl3 are added, the content of the chlorophyll and the osmotic adjustment substance of the potato seedling leaves under different water conditions is effectively improved, the generation rate of the active oxygen metabolic substance is reduced, And the activity of the antioxidant enzyme is greatly enhanced. Under the treatment of water-2, the content of chlorophyll, soluble sugar and proline in potato leaves increased by 162.35%, 59.59%, 154.45%, MDA content, O _ 2 ~-. The production rate and relative conductivity decreased by 67.70%, 25.29%, 37.70% respectively, the anti-oxidation enzyme activity increased by 38.35%, 28.08%, 66.00%, and the dry weight of the potato in the mature period, the number of the ground branches, the weight of the ground and the underground part, the number of the above-ground branches, the weight of the sweet potato increased by 67.87%, 21.68% and 32.81%, respectively. 49.05%, 187.50% and 63.91%. An appropriate amount of chlorinating agent is added under the drought stress, so that the osmotic adjustment substances in the seedling plant cells can be improved, the activity of the antioxidant enzymes is enhanced, the accumulation of free radicals is reduced, the damage to the growth and development of the potato seedlings is relieved by the drought stress, the drought tolerance of the potato plants is improved, And provides the guarantee for the stable and stable production of the potato under the drought stress. In conclusion, the reasonable and effective fertilizer application measures and the fertilizer application amount not only ensure the nutrient supply required by the growth and development of the potatoes, but also increase the assimilation and accumulation of the potato seedling leaves on the carbon, The stress damage to the potato plants is reduced, the normal growth and development of the plants is ensured, the resistance of the potato plants under the drought stress is enhanced, the yield of the potato tubers is improved, and the nutrition and the quality of the tubers are improved.
【学位授予单位】：甘肃农业大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：S532

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