【作者】 冯宝；

【导师】 朱自均；

【作者基本信息】 西南农业大学 ， 作物栽培学与耕作学， 2004， 硕士

【摘要】 以D优527为材料，采用旱育秧、湿润育秧两种育秧方式及旱育秧抛(栽)与湿润育秧抛(栽)，观察采用定距播种技术在不同规格下形成的秧苗群体在滞增叶龄期、滞增后1个叶龄期和滞增后2个叶龄期的秧苗素质、本田初期分蘖早发及对产量的影响。试验结果如下： 1．密度合理、播种均匀是多蘖的前提，滞增叶龄期内秧苗素质最好，且秧龄弹性大，生产适应性广 因播种密度的不同，秧苗群体进入滞增叶龄期的时间不同，随密度的减小而延长，从而使秧龄弹性增大。滞增叶龄期后的旱育秧苗比滞增叶龄期内的秧苗叶龄大1～2个叶龄，单株带蘖下降0.3％～75％，发根力弱3.3％～94.3％；同样滞增叶龄期后的湿润育秧秧苗比滞增叶龄期的秧苗叶龄大1～2个叶龄，单株带蘖下降4.8％～100％，发根力在-4.5％～89.9％浮动，总体呈下降趋势。 不同秧苗素质对本田初期新发分蘖的影响也是不一样的，滞增叶龄期的旱育秧苗与滞增叶龄期后的秧苗相比，本田初期新发分蘖多7.9～70.3％；滞增叶龄期的湿润育秧秧苗与滞增叶龄期后的秧苗相比，本田初期新发分蘖多1.5～42.9％。 滞增叶龄期移植的秧苗抗植伤的能力比滞增后1、2个叶龄期移植的秧苗强。滞增叶龄期移植的秧苗出叶速度比滞增后1、2个叶龄期移植的秧苗快，叶片伸长和叶枕距的影响比滞增后1、2个叶龄期移植的秧苗小，本田期前四个分蘖发生的时间比滞增后1、2个叶龄期移植的秧苗早，且分蘖缺位叶位低、少。 颖花分化期各生理指标的比较认为滞增叶龄期的秧苗有利于植株体内积累更多的贮藏物质，形成了较好的“源”，为水稻的高产创造了更有利的条件。 2．秧苗素质的下降随密度的减小而放慢 从秧苗素质的调查比较可以看出，旱育密播处理当进入滞增叶龄期后秧苗素质快速下降，其在滞增后2个叶龄期时新根条数、新根总长比在滞增叶龄期分别下降72.4％、94.3％，而旱育稀播处理当进入滞增叶龄期后秧苗素质下降缓慢，在滞增后2个叶龄期时新根条数、新根总长较在滞增叶龄期分别下降8.3％和26.1％。其它如一叶蘖、单株带蘖数等指标均是密播处理下降最快。湿润育秧的秧苗表现为中等密度的秧苗素质下降比较慢，其在滞增后2个叶龄期时新根条数、新根总长较在滞增叶龄期分别下降7.3％、84％，而密播、稀播处理在滞增后2个叶龄期时新根条数、新根总长分别比在滞增叶龄期下降77.5％、89.8％和66％、81.1％。 3．秧苗素质对立苗及本田初期的影响西南衣业大学硕上学位论文-一—......-一一—一一—生一魁哑丝 同一播量处理不同时期抛植以滞增叶龄期的立苗需时最短，同一时期抛植不同播量处理以密播的立苗需时最短，稀播的需时最长;有盘的立苗速度快于同一时期不同播量的其它处理，这主要是密播的秧苗进入滞增叶龄期时的叶龄小，植株个体较小，抛植前儿小时在苗床上浇透水，能实现根部带土抛植，因而抛植立苗速度明显加快。秧苗素质对本田初期分桑早发有显著的影响。同一播量处理不同时期抛植以滞增叶龄期的秧苗3Od内新发分孽最多;同一时期抛植不同播量处理以稀播的秧苗30d内新发分禁最多。4.秧苗素质对产量的影响: 早育秧同一时期移植不同播量处理，其产量随密度的增加而减小。这主要是因为同一时期移植不同播量处理的秧苗的素质以稀播处理最好，中密播次之，密播相对最差，抛植后稀播处理的发根力强，分孽能力旺盛(移植30d内新增茎孽数以稀播处理最多)，最终有效分孽最多，而垫壳又比中密不垫壳处理好，这一点在结论2已有说明。同一播量处理不同时期移植，其产量随移植时间的延后而下降，即以滞增叶龄期移植的秧苗产量最高。主要因为滞增叶龄期秧苗的素质比其后两个时期好，这在结论1已有表述。另外随着移植时间的延后，播种密度越稀，栽植的产量比抛植的越高。在本试验中以稀播处理的最明显，即稀播处理的秧苗在滞增叶龄期后不宜抛植，只宜栽植。湿润育秧秧苗也以秧苗素质最好的稀播处理在滞增叶龄期的产量最高。更多还原

【Abstract】 D-you-527 as material, two seeding-raised ways of dryland seeding-raised with scattering (transplanting) and wetland seeding-raised with scattering (transplanting) were tested to find how population of seedlings from different fixed density sowing at the leaf age of stagnating increase, 1-leaf after stagnating increase and 2-leaf stagnating increase influence seedling quality, early tiller at initial stage of field and yield. The main results were as follows:1.Appropriate density and even sowing are precondition of enough tillers. At the leaf age of stagnating increase, seedling quality is the best and seedling age is more flexible, which could adapt wide time in produce.The date of the leaf age of stagnating increase that seedling population stepped into varied with different sowing density. The time would decrease with sowing density decreasing, which increase flexibility of seedling age. The leaf age of dryland seeding-raised seedling after stagnating increase is 1-2 leaves age older than that in the leafage of stagnating increase. Tillers per plant deceased 0.3%-75%, and potential of growing roots decreased 3.3%-94.3%. Meanwhile the leaf age of wetland seeding-raised seedling after stagnating increase is 1-2 leaves age older than that in the leaf age of stagnating increase. Tillers per plant deceased 4.8%-100%, and potential of growing roots remained about -4.5%~89.9%, but the tendency was decreasing as a whole.The effects different seedling quality on new tillers at initial stage of field was not same either. The new tillers of dryland seeding-raised seedling after stagnating increase was higher 7.9-70.3% than that in the leaf age of stagnating increase, while the new tillers of wetland seeding-raised seedling after stagnating increase is higher 1.5-42.9% than that in the leaf age of stagnating increase.The ability of anti-injury of seedlings transplanted during the leaf age of stagnating increase were stronger than that after stagnating increase and 1-2 leaves stagnating increase. The speed of growing new leaves of seedlings transplanted during the leaf age of stagnating increase was faster than that after stagnating increase and 1-2 leaves stagnating increase. The effect of injury on leaf elongation and distance between leaf-pillows were smaller. The time of forming first 4-tiller was earlier and leaf location of no tiller was low and little.During time of spikelets differentiation, leaf age of stagnating increase was beneficial to accumulate more dry matter, which formed better source to create advantageous conditions for high yield of rice.2. Speed of seedling quality decreasing became slower with lower sowing densityWhen seedlings from dryland seeding-raised and high sowing density stepped into leaf age of stagnating increase, seedling quality began to decrease quickly. And amount and length of total new roots of seedlings from 2-leaf age after stagnating increase were lower 72.4% and 94.3% than that of leaf age of stagnating increase respectively. While when seedlings from dryland seeding-raised and low sowingamount and length of total new roots of seedlings from 2-leaf age after stagnating increase were lower 8.3% and 26.1% than that of leaf age of stagnating increase respectively. Other traits such as one-leaf tiller and tillers per plant decreased fastest by the transaction of high sowing density. Seedling quality from wet-land seeding-raised with middle sowing density decreased relatively slow, in which amount and length of total new roots of seedlings from 2-leaf age after stagnating increase were lower 7.3% and 84% than that of leaf age of stagnating increase respectively. While by the transaction of high and low sowing density amount and length of total new roots of seedlings from 2-leaf age after stagnating increase were lower 77.5%, 89.8% and 66%, 81.1%h than that of leaf age of stagnating increase respectively.3. Effect of seedling quality on the upright of seedling and tillers during initial stage of fieldAt same sowing density and different scattering date, ne更多还原