【作者】 罗兴录；

【导师】 林彦铨；

【作者基本信息】 福建农林大学 ， 作物栽培学与耕作学， 2003， 博士

【摘要】 广西是中国木薯生产的主产区，全区年种植面积23～28万hm~2，占全国木薯种植面积的60％。木薯是淀粉作物，收获的产品主要是块根。如何促进块根分化、发育和淀粉积累，一直是木薯栽培要研究解决的关键问题。 本研究以SC124、GR911、GR891三个木薯品种为材料，采用云大—120、芸苔素、多效好、乙烯利、多效唑五种植物生长调节剂，对木薯生长、块根分化发育和淀粉积累的化学调控及其生理基础进行研究。结果表明：(1)木薯用云大-120、芸苔素、多效好浸种能提高种茎吸水速率，增强种茎淀粉酶活性，提高种茎可溶性糖含量；促进种茎根芽萌发，提高种茎发芽势和发芽率；提高幼苗抗坏血酸氧化酶、多酚氧化酶、过氧化氢酶的活性；其中以云大-120浸种效果最好；(2)木薯用云大-120、芸苔素、多效好浸种和喷施植株，能提高木薯叶片硝酸还原酶的活性；促进茎叶生长，增强根系活力，促进叶片叶绿素形成，提高叶片叶绿素含量，增强叶片光合强度；其中以云大—120作用效果最显著；(3)木薯用云大-120、芸苔素、多效好浸种和喷施植株，可以促进块根分化发育，单株块根数比对照明显增加；(4)木薯在生长前期用云大-120浸种和喷施植株，在生长中后期用乙烯利、多效哇喷施叶面，可以促进同化物向地下部转运，促进块根发育和淀粉积累，块根长、块根粗、块根重和块根淀粉含量都比对照显著提高;(5)木薯在生长前期施用云大一120，在生长中后期施用乙烯利、多效哇能增强块根淀粉合成酶、ADPG焦磷酸化酶和UDPG焦磷酸化酶的活性，增强块根淀粉积累能力;(6)木薯在生长中后期施用乙烯利、多效哇能提高过氧化物酶的活性;对促进木薯工艺成熟，提高木薯块根淀粉含量有重要的作用;(7)木薯在生长前期施用云大一120(浸种和喷施植株)，在生长中后期施用乙烯利、多效哇(喷施叶面)能改善木薯主要经济性状，块根产量和淀粉产量比对照显著提高。 本研究从种茎发芽到工艺成熟对木薯生长、块根分化发育和淀粉积累的化学调控进行系统研究，并率先发现木薯用云大一120、芸苔素、多效好浸种不但能增强种茎淀粉酶的活性，提高种茎可溶性糖的含量，促进种茎根芽萌发，提高种茎发芽势和发芽率，增强幼苗抗坏血酸氧化酶、多酚氧化酶、过氧化氢酶的活性，而且能促进块根分化发育，对提高块根产量具有显著的作用;在木薯生长期间用云大一120、芸苔素、多效好喷施植株，能增强叶片硝酸还原酶的活性;增强植株根系活力;促进叶绿素形成，增强叶片的光合机能;在木薯生长中后期施用乙烯利、多效哇能提高块根淀粉合成酶、ADPG焦磷酸化酶、UDPG焦磷酸化酶的活性，增强块根淀粉积累能力，促进块根淀粉积累，提高块根淀粉含量。这些研究成果对木薯高产高粉栽培具有重要的指导意义。更多还原

【Abstract】 Guangxi is main province planting cassava in China , in which the area of cassava is between 230 and 280 thousand hectares each year , which is 60 percent of the area of cassava in all the country. Cassava is a starch crop of which the product harvested is the root tubers. How to promote the root tubers differentiating and developing and the sarch accumulating is a problem that people always try to study and solve.The effects and physical bases of chemical control of plant growth and root tuber differentiation and starch accumulation of cassava were studied in this experiment, of which three varieties of cassava (SCI24, GR911 and GR891 ) and five plant growth regulators(Homobrassinolide,Rapebrassinolide,Multi-Effect-Age-nt, Ethrel and Multi-Effect-Triazole ) were used as material. The results were reported as follows: (1) It was shown that the rates of sucking water, the activities of amylase, ascorbic acid oxidase, polyphenol oxidase and catalase, the soluble sugar contents andthe rates of, germinating of seed-stems which were soaked with Homobrassinolide, Rapebrassinolide and Multi-Effect-Agent were higher than those of with water ; (2) It was also shown that soaking the seed-stem and spraying the leaves of cassava with Homobrassinoli Rapebrassinolide and Multi-Effect-Agent can increase the nitrate reductases activity, root activities , chlorophyll content and photosynthetic intensity of cassava leaves;(3)Soaking the seed-stems and spraying the leaves of cassava with Homobrassinolide Rapebrassinolide and Multi-Effect-Agent can promote root tubers differntating and the root tuber numbers of plant treated with Homobrassinolide, Rapebrassinolide and Multi-Effect-Agent were more than those of with water; (4) It was found that soaking the seed-stems and spraying the leaves of cassava with Homobrassinolide in early stage and spraying the leaves with Ethrel and Multi-Effect-Triazole in the middle and late stage of cassava growth can promote photosynthate transporting from the stems and leaves to the roots so that can promote root tubers growing and increase starch accumulating in the root tubers,and the lengths,diameters and weights of root tuberand the starch contents in the root tuber were higher than those of with water; (5) The results also showed that when the seed-stems and the leaves of cassava were treated with Homobrassinolide in early stage of cassava growth and with Ethrel and Multi-Effect-Triazole in the middle and late stage ,the activities of starch synthetase, ADP glucose pyrophosphorylase and UDP glucose pyrophosphorylase were higher than those of other treats; (6) Soaking the seed-stems and spraying the leaves of cassava with Homobrassinolide in early stage and the leaves with Ethrel and Multi-Effect-Triazole in the middle and late stage can evidently increase the activity of peroxidase; (7) The economic characters of cassava evidently improved and the yield and starch content of root tubers notably increased when the seed-stems and the leaves were treated with Homobrassinolide in early stage of cassava growth and with Ethrel and Multi-Effect-Triazole in the middle and late stage.It was found first in this experiment that not only the amylase activities , the soluble sugar contents and the rates of germination of seed-stems and the activities of ascorbic acidoxidase , polyphenol oxidase and catalase of the seedlings but also the root tuber differentiations evidently increased with soaking the seed-stems of cassava with Homobrassinolide, Rapebrassinolide and Multi-Effect-Agent, and the nitrate reductases activities, the root activities, chlorophyll content and photosynthetic intensity of cassava leaves notably increased with spraying the plant with Homobrassinolide, Rapebrassinolide and Multi-Effect-Agent. It was also found first in this experiment that the activities of starch synthetase, ADP glucose pyrophosphorylase and UDP glucose pyrophosphorylase and the starch contents of root tuber with spraying the leaves with Ethel and Multi-Effect-Triazole in the middle and late s更多还原