發(fā)布時(shí)間：2018-05-19 08:06

  本文選題：紫花苜蓿 + 秋眠性��； 參考：《南京農(nóng)業(yè)大學(xué)》2016年博士論文

【摘要】：南方農(nóng)區(qū)紫花苜蓿(Mecdicago sativa L.)與糧經(jīng)作物復(fù)種的短期栽培模式已取得了很大的發(fā)展。由于是短期栽培,選育能在短時(shí)間內(nèi)獲得高產(chǎn)的速生品種顯得尤為重要。但是,選育優(yōu)良品種和集成高產(chǎn)栽培技術(shù)需要有在這種生態(tài)條件下對(duì)紫花苜蓿產(chǎn)量形成及其生理機(jī)制的研究基礎(chǔ)來支撐。本文主要研究了在南方農(nóng)區(qū)秋播和春播的短期栽培模式下,秋眠型、半秋眠型和非秋眠型紫花苜蓿地上部分枝(根頸分枝和莖分枝)的生長特性對(duì)產(chǎn)量的影響,以及根系碳源和氮源的積累對(duì)刈割后地上部再生能力的影響,以期為選育適合南方短期速生栽培的紫花苜蓿品種及其高產(chǎn)栽培技術(shù)提供理論依據(jù)。主要研究結(jié)果如下:在秋播翌年刈割三茬的短期栽培條件下,對(duì)不同秋眠類型紫花苜蓿產(chǎn)量和地上部分枝生長關(guān)系的研究結(jié)果表明:秋眠級(jí)高的品種無論是在第一茬、第二茬還是第三茬均能獲得較高的單株產(chǎn)量。綜合三茬的結(jié)果,隨著秋眠級(jí)的升高,總的單株產(chǎn)量顯著增加。紫花苜蓿的根頸分枝數(shù)和莖分枝數(shù)在不同秋眠級(jí)品種間差異不大,但根頸分枝單枝重和莖分枝單枝重均隨著秋眠級(jí)的升高而顯著增加。根頸分枝是決定紫花苜蓿春季第一茬單株產(chǎn)量的主要分枝類型;莖分枝的比重在第二、第三茬中大幅上升,并成為決定第三茬單株產(chǎn)量的主要分枝類型;綜合三茬結(jié)果,根頸分枝仍是決定紫花苜蓿產(chǎn)量的主要分枝類型。分枝單枝重對(duì)紫花苜蓿單株產(chǎn)量的影響大于分枝數(shù);根頸分枝單枝重是決定春季第一茬單株產(chǎn)量的主要因子;隨著刈割次數(shù)的增加,莖分枝單枝重逐漸成為決定單株產(chǎn)量的主要因子。在春播僅刈割兩茬的短期栽培條件下,對(duì)不同秋眠類型紫花苜蓿產(chǎn)量和地上部分枝生長關(guān)系的研究結(jié)果表明:第一茬,非秋眠型紫花苜蓿品種的干草產(chǎn)量顯著高于秋眠型品種;第二茬品種間的干草產(chǎn)量無顯著差異;綜合兩茬來看,秋眠級(jí)高的品種的干草產(chǎn)量依然存在優(yōu)勢(shì)。第一茬中,根頸分枝對(duì)產(chǎn)量的貢獻(xiàn)率占絕對(duì)的主導(dǎo)地位,達(dá)到94.41%～96.01%;第二茬中,莖分枝的比重大幅上升至38.47%～44.45%,但仍未能成為決定第二茬產(chǎn)量的主要分枝類型;綜合兩茬結(jié)果,根頸分枝是決定紫花苜蓿產(chǎn)量的主要分枝類型。分枝單枝重對(duì)紫花苜蓿產(chǎn)量的影響大于每株分枝數(shù),且根頸分枝單枝重是決定每一茬草產(chǎn)量的主要因子。在秋播短期栽培條件下,對(duì)不同秋眠類型紫花苜蓿地上部再生和根系養(yǎng)分關(guān)系的研究結(jié)果表明:第一、第二和第三茬刈后12 d的地上部再生量和再生速度均隨著品種秋眠級(jí)的升高而顯著增加。刈割后0、6和12 d的根系C源(可溶性糖、淀粉和總的非結(jié)構(gòu)性碳水化合物)含量在品種間的變化規(guī)律不明顯,N源(總氮和可溶性蛋白)含量隨品種秋眠級(jí)的升高呈增加的趨勢(shì)。刈割時(shí)營養(yǎng)貯藏蛋白(VSPs)的含量在品種間的差異不顯著。而C源和N源總量則隨著品種秋眠級(jí)的升高呈顯著增加的趨勢(shì)。各品種刈割后的0-12d內(nèi),其C源和N源的含量和總量均下降明顯,養(yǎng)分消耗量隨品種秋眠級(jí)的升高顯著增加。刈割后12 d的地上部再生量與刈割時(shí)根系C源和N源的含量并未持續(xù)呈顯著正相關(guān),但與其總量和刈后12 d的養(yǎng)分消耗量均持續(xù)呈顯著正相關(guān)。在春播短期栽培條件下,對(duì)不同秋眠類型紫花苜蓿地上部再生和根系養(yǎng)分關(guān)系的研究結(jié)果表明:第一茬刈后14d的地上部再生量和再生速度在品種間差異不顯著,第二茬刈后14 d半秋眠型和非秋眠型品種的地上部再生量和再生速度高于秋眠型品種。刈割后0、7、14和21 d的根系C源含量在品種間的變化規(guī)律不明顯,N源含量隨品種秋眠級(jí)的升高呈增加的趨勢(shì)。刈割時(shí)VSPs的含量在品種間的差異不顯著。而C源和N源總量則隨著品種秋眠級(jí)的升高呈顯著增加的趨勢(shì)。各品種刈割后的0-14d內(nèi),其C源和N源的含量和總量均下降明顯,養(yǎng)分消耗量隨品種秋眠級(jí)的升高呈顯著增加的趨勢(shì);刈割后的14-21 d,其C源和N源的含量和總量開始上升。刈割后14 d的地上部再生量與刈割時(shí)根系C源含量的相關(guān)性不顯著,與N源含量并未持續(xù)呈顯著正相關(guān),但與C源和N源的總量和刈后14天的養(yǎng)分消耗量均持續(xù)呈顯著正相關(guān)。綜上所述,紫花苜蓿在冬季溫和的南方地區(qū)進(jìn)行短期栽培利用時(shí),選用非秋眠型品種有利于提高產(chǎn)量。根頸分枝是決定紫花苜蓿產(chǎn)量的主要分枝類型,且分枝單枝重對(duì)產(chǎn)量的影響大于分枝數(shù)。因此,在選育適合南方地區(qū)短期栽培利用的品種時(shí),應(yīng)重視根頸分枝的發(fā)生發(fā)育,且應(yīng)以分枝重量作為首要選擇標(biāo)準(zhǔn)。決定紫花苜蓿刈割后早期再生能力的是根系養(yǎng)分的總量而非含量,因此為提高紫花苜蓿地上部的再生量需擴(kuò)大根系的庫容。
[Abstract]:The short-term cultivation model of Mecdicago sativa L. in Southern agricultural region and the replanting of grain crops has made great progress. Because it is short term cultivation, it is very important to select and breed the fast-growing varieties with high yield in a short time. However, the selection of fine varieties and integrated high-yield cultivation techniques need to be purple under this ecological condition. In this paper, the effects of the growth characteristics of the branches of autumn dormant, semi dormant and non dormant Alfalfa on yield, as well as the product of root carbon and nitrogen sources, were studied in the short term cultivation mode of autumn sowing and spring sowing in the Southern agricultural region. In order to provide a theoretical basis for breeding alfalfa varieties and high yield cultivation techniques suitable for short-term and fast-growing cultivation in the south, the main results are as follows: under the short-term cultivation conditions of three stubble cropping in the next year of autumn sowing, the yield of alfalfa and the growth of some branches on the ground of different fall dormancy types are made. The results of the study showed that high fall dormant varieties were able to obtain higher yield per plant in the first, second or third stubble. As the result of the three stubble, the total yield of the single plant increased significantly with the rise of the fall dormancy grade. The branch single branch weight and the single branch weight of the stem branch increased significantly with the rise of the fall dormancy grade. The root neck branch was the main branch type determining the first crop yield of Alfalfa in the spring, and the proportion of the stem branches increased significantly in the second and third stubble, and became the main branch type determining the yield of the third single plant; the comprehensive three stubble results, the root neck. Branch is still the main branch that determines the yield of alfalfa. Branch single branch weight has greater influence on the yield of Alfalfa than the branch number; the single branch weight of root neck branch is the main factor determining the yield of the first crop in spring. Under the short-term cultivation conditions of cutting two stubble, the study on the relationship between the yield of alfalfa and the growth of the branches on the ground with different fall dormancy types showed that the first, the hay yield of the non dormant alfalfa varieties was significantly higher than that of the autumn dormancy type, and the hay yield between the second stubble varieties had no significant difference, and the fall dormant level was high in the two stubble. In the first crop, the contribution rate of the root neck branch to the yield was dominant, reaching 94.41% to 96.01%, and the proportion of the stem branches increased to 38.47% ~ 44.45% in the second stubble, but it still failed to be the main branch to determine the second crop yield; the root and neck branches were determined by the comprehensive two results. The main branch type of alfalfa yield. The effect of branch single branch weight on the yield of alfalfa was greater than the number of branches per plant, and the single branch weight of root neck was the main factor determining the yield of every stubble. In the short term cultivation of autumn sowing, the study on the relationship of root regeneration and root nutrient of Alfalfa with different fall dormancy types showed that: first The regeneration rate and regeneration rate of 12 d after second and third clipping were significantly increased with the increase of autumn dormancy. The content of C source (soluble sugar, starch and total unstructured carbohydrates) in root system of 0,6 and 12 d after mowing was not obvious, and the content of N source (total nitrogen and soluble protein) with autumn dormancy The content of VSPs was not significant when mowing, while the total amount of C source and N source increased with the increase of fall dormancy level. The content and total of C source and N source decreased obviously in 0-12d after mowing, and the nutrient consumption was increased with the fall dormancy grade of varieties. There was no significant positive correlation between the shoot regeneration of 12 d after mowing and the content of root C source and N source during mowing, but it had a significant positive correlation with the total amount and the 12 d nutrient consumption after mowing. The results showed that there was no significant difference in the regeneration rate and regeneration rate of 14d after the first clipping. The growth and regeneration rate of the 14 d and half fall dormant and non fall dormant types after the second clipping were higher than those of the autumn dormancy type. The C source content of the root of 0,7,14 and 21 d after mowing was not obvious, and the content of N source was with the content of the root. The increase of autumn dormancy level was increasing. The difference of VSPs content was not significant when mowing, but the total amount of C source and N source increased with the increase of fall dormancy level. The content and total of C source and N source decreased obviously in 0-14d after mowing, and the nutrient consumption was increased with the increase of autumn dormancy grade. The tendency to increase significantly; the content and total amount of C source and N source began to rise at 14-21 d after mowing. The correlation of the root regeneration of 14 d after mowing was not significantly correlated with the C source content of the mowing, and did not have a significant positive correlation with the content of N source, but the total amount of the source of C and the source of N and the nutrient consumption of the 14 days after mowing were in a significant positive phase. In summary, the selection of non fall dormant varieties is beneficial to the increase of yield when the alfalfa is used for short-term cultivation in the mild southern region in winter. The root neck branch is the main branch that determines the yield of alfalfa, and the effect of branching single branch weight on yield is greater than the number of branches. The occurrence and development of the root and neck branch should be paid attention to, and the branch weight should be taken as the primary choice. The total root nutrient content is not the content of the early regenerative capacity of alfalfa. Therefore, the capacity of root system should be expanded to increase the regeneration of alfalfa.
【學(xué)位授予單位】：南京農(nóng)業(yè)大學(xué)
【學(xué)位級(jí)別】：博士
【學(xué)位授予年份】：2016
【分類號(hào)】：S541.9

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1 陸曉燕;南方農(nóng)區(qū)短期栽培紫花苜蓿分枝生長特性和根系碳氮養(yǎng)分的研究[D];南京農(nóng)業(yè)大學(xué);2016年

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本文編號(hào)：1909345