本文選題：大豆　切入點：低鉀脅迫　出處：《沈陽農(nóng)業(yè)大學》2017年碩士論文　論文類型：學位論文

【摘要】：本試驗以課題組多年篩選的耐低鉀型大豆T40、T36、WM和低鉀敏感型大豆GD8521為試驗材料,于2015-2016年采用水培試驗與大田試驗相結(jié)合的方式,設HK(對照)和LK(低鉀)兩個處理,對低鉀脅迫下大豆干物質(zhì)積累、營養(yǎng)元素吸收、滲透調(diào)節(jié)物質(zhì)、光合特性、有機酸分泌及代謝、葉片超顯微結(jié)構(gòu)以及大豆產(chǎn)量等方面的差異進行深入研究,明確低鉀脅迫對根系衰老的影響及其內(nèi)在聯(lián)系,揭示低鉀脅迫下大豆根系衰老的生理生化機制,為探索耐低鉀型大豆的分子育種提供理論依據(jù)。本試驗研究結(jié)果如下:1.低鉀處理的大豆總根長、根體積和根平均直徑均小于對照處理,而根表面積卻大于對照處理,說明低鉀脅迫在一定程度上促進了根系的橫向分布,但在縱向分布方面作用較小。低鉀脅迫下,耐低鉀型大豆品種有較高且較穩(wěn)定的根表面積和根體積來保證其從土壤中充分吸收養(yǎng)分,促進植株正常生長,從而延緩植株衰老。2.低鉀脅迫降低了植株的生物量。在低鉀環(huán)境下,耐低鉀型大豆在不同生育時期有更穩(wěn)定的干物質(zhì)積累量。低鉀敏感型大豆GD8521根冠比在不同生育時期變化趨勢較大,成熟期其根冠比的大幅度下降說明是由其根系提前衰老導致的。耐低鉀型大豆有更穩(wěn)定的根冠比來適應土壤中鉀的變化,保證植株自身生長發(fā)育,從而達到延緩根系衰老的效果。3.低鉀脅迫降低了大豆植株的氮、磷、鉀積累量,對根系中磷積累量較不敏感,對各器官鉀積累量影響最顯著。耐低鉀型大豆在低鉀脅迫環(huán)境下能保持更穩(wěn)定的養(yǎng)分吸收為植物生長提供物質(zhì)循環(huán)和能量轉(zhuǎn)化,延緩植株衰老,從而延緩根系衰老。4.低鉀脅迫降低了大豆葉片的蒸騰速率、凈光合速率和氣孔導度,導致了胞間CO2濃度的升高。低鉀處理提高了大豆的光補償點,降低了光飽和點和凈光合速率,其中GD8521的光飽和點降低了 19.64%,T40降低了 12.57%。耐低鉀型大豆在低鉀脅迫中能保持穩(wěn)定的胞間CO2濃度、蒸騰速率、凈光合速率和氣孔導度及光補償點和光飽和點,延長了葉片的功能期,保證植株的能量供給,為延緩植株衰老作出了一定的貢獻。5.低鉀脅迫下大豆根系可溶性糖含量下降,而脯氨酸和游離氨基酸含量升高。在出苗后90 d(R6),T40和WM低鉀處理根系游離氨基酸含量分別比HK(對照)升高54.67%和48.94%,而GD8521為41.02%。耐低鉀型大豆在低鉀環(huán)境下有較低的可溶性糖含量及較高的游離氨基酸含量來保持細胞膨壓以達到滲透調(diào)節(jié)能力。6.GD8521的有機酸含量在不同K+濃度間差異不顯著,而耐低鉀型大豆在不同K+濃度條件下能通過自身調(diào)節(jié)其有機酸含量以保持較強的代謝活動來維持與外界的物質(zhì)交流,從而延緩根系衰老。7.耐低鉀型大豆在低鉀環(huán)境下能維持穩(wěn)定的細胞結(jié)構(gòu),葉綠體內(nèi)基質(zhì)濃厚,基粒片層排列整齊,葉綠體周圍有較多線粒體,線粒體膜完整且嵴清晰。穩(wěn)定的細胞結(jié)構(gòu)能保持細胞功能的正常,有效延長葉片功能期,保證光合作用健康有序進行,從而對延緩根系衰老做出貢獻。8.低鉀處理下,T40和WM產(chǎn)量降低幅度較小,比對照分別下降37.06%和46.34%,差異不顯著(P0.05);而GD8521產(chǎn)量下降幅度較大,為64.77%,差異達顯著水平(P0.05)。說明耐低鉀型大豆通過自身調(diào)節(jié)產(chǎn)量性狀來維持較為穩(wěn)定產(chǎn)量,從而反映出其有更強的適應低鉀環(huán)境能力。
[Abstract]:In this experiment research group screening of Low Potassium Tolerant Soybean T40, T36, WM and low potassium sensitive soybean GD8521 as experimental materials, 2015-2016 years hydroponic experiments and field experiments, HK (control) and LK (low potassium) two treatments on the accumulation of large Dried tofu material potassium stress, nutrient absorption, osmotic adjustment, photosynthetic characteristics, organic acid secretion and metabolism, in-depth study of differences in leaf ultrastructure and the yield of soybean and other aspects of the specific effects of low potassium stress on root senescence and its relation to reveal the physiological and biochemical mechanism under low potassium stress in soybean root senescence, provide in order to explore the theoretical basis for molecular breeding of Low Potassium Tolerant Soybean. The results are as follows: 1. the low potassium of soybean root length, root volume and root average diameter were less than CK, while the root surface area is larger than that of the control treatment, suggesting that low Potassium stress to a certain extent promoted the transverse distribution of the root system, but a smaller role in the vertical distribution. Under low potassium stress, low potassium tolerant soybean varieties have a higher and more stable root surface area and root volume to ensure sufficient nutrient absorption from the soil, promote the normal growth of plants, thus delaying plant senescence.2. low potassium stress reduced plant biomass. In low potassium environment, low Potassium Tolerant Soybean has a more stable dry matter accumulation in different growth periods. Low potassium sensitive soybean root GD8521 is larger than the change in different growth period, mature period trend, the ratio of root to shoot was decreased greatly that is caused by the root of premature aging. Low Potassium Tolerant Soybean has a more stable root shoot ratio to adapt to the change of soil potassium in the plant, ensure their growth and development, so as to achieve the effect of delaying the senescence of root.3. low potassium stress reduced soybean plant The nitrogen, phosphorus, potassium accumulation amount is less sensitive to phosphorus accumulation in roots, the organs of K accumulation. The most significant effect in low potassium stress environment can maintain more stable nutrient absorption material cycle and energy transformation for plant growth in Low Potassium Tolerant Soybean, delay the senescence of plant, thus delaying the root the aging of.4. low potassium stress reduced the transpiration rate of soybean leaves, the net photosynthetic rate and stomatal conductance, leads to increased intercellular CO2 concentration. Low potassium treatment increased the light compensation point of soybean, reduced the light saturation point and photosynthetic rate, which GD8521 the light saturation point decreased by 19.64%, T40 12.57%. decreased in low potassium tolerant soybean CO2 concentration in low potassium stress can maintain the stability of the intercellular transpiration rate, net photosynthetic rate and stomatal conductance and the light compensation point and the light saturation point, prolong the functional period of the leaves, guarantee the supply of energy plants, to retard plant Aging has made an important contribution to.5. under low potassium stress the soluble sugar content in soybean roots decreased, but the proline and free amino acid content increased. In 90 after the emergence of D (R6), T40 and WM in low potassium free amino acid content in root was higher than HK (control) increased by 54.67% and 48.94%, and the organic acid content of free amino acids for GD8521 the content of 41.02%. in low potassium tolerant soybean soluble sugar content and high low in low potassium environment to maintain cell turgor in order to penetrate such.6.GD8521 in different K+ concentrations were not significantly different, while the low Potassium Tolerant Soybean to maintain metabolic activity to maintain strong and material exchanges outside the self adjustment of the organic acid content in different K+ concentration conditions, thereby delaying the senescence of root cell structure of.7. in Low Potassium Tolerant Soybean can remain stable in low potassium environment, the chloroplast stroma strong, grana lamellae In order, there are more mitochondria around the chloroplasts, mitochondria membrane and cristae. Stable cell structure can maintain the normal function of cell, prolong the functional period of leaves photosynthesis, ensure healthy and orderly, so as to make the root of low potassium with.8., T40 and WM production decreased slightly, down 37.06% and 46.34% compared to the control, the difference was not significant (P0.05); while the GD8521 yield decreased greatly, was 64.77%, the difference reached significant level (P0.05). The results showed that low Potassium Tolerant Soybean to maintain stable yield traits by self regulation, which reflects the stronger ability to adapt to low potassium environment.

【學位授予單位】：沈陽農(nóng)業(yè)大學
【學位級別】：碩士
【學位授予年份】：2017
【分類號】：S565.1
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本文編號：1576357