论文标题:伤根对作物生长及其水分利用效率影响的研究
Purity Identification of tomato hybrid by RAPD markers & Searching for RAPD markers linked to the WO and Tm-2 gene in tomato
论文作者 柴世伟
论文导师 刘文兆,论文学位 硕士,论文专业 土壤学
论文单位 西北农林科技大学,点击次数 154,论文页数 60页File Size1116k
2001-06-01论文网 http://www.lw23.com/lunwen_36871082/ 伤根 节水农业 作物生长 光合作用 产量 谷子 玉米
root cutting; water saving farming; crop growth; photosynthesis; yield; millet;maize
本文利用谷子盆栽试验、谷子根系观察盒试验以及玉米小区试验，研究了伤根措施对谷子和玉米生长及其水分利用效率的影响，试验结果表明： 1．苗期适度伤根能够提高作物叶片光合速率，降低谷子叶片蒸腾速率和气孔导度，而苗期伤根量较严重或拔节期和孕穗期的处理则会降低谷子叶片光合速率，提高叶片的蒸腾速率和气孔导度。 2．大多数的伤根处理都降低了作物株高，谷子叶面积在后期的萎缩速度都小于对照，即伤根对谷子叶面积在后期防止早衰、延长活力等方面有一定的作用；伤根后半月时，伤根处理之生物量都没有对照高。 收获时在80%田间持水量条件下，谷子生物量提高在1.5-24.7%之间；50%田间持水量时，生物干重降低幅度在2.9-19.0%之间。而就玉米收获期测定的生物产量看，三种伤根处理的生物产量均较对照为高。3．谷子根系在土壤中的分布以0~50厘米为主，伤根处理的相对根量在土壤0~15厘米的分布少于对照处理，而在15厘米以下的根量多于对照，且总根量也超过了对照处理。伤根后短期内会对根系生长产生抑制作用，到了谷子生长的生育后期，对照处理的根系生长减缓时，伤根处理根系生长还在进行，其根系活力得到了延伸。比较两种水分条件下谷子根量可以看出，高水分条件下易发新根、毛根，根量生长状况明显好于低水分条件。4．80%田间持水量时，随着伤根程度的加剧和伤根时间的后移，谷子子粒产量都在下降；而在50%田间持水量时，前期伤根量适度的处理有助于谷子子粒产量的提高（以fm处理之产量最高），而伤根量较为严重的处理和孕穗期伤根的处理都降低了谷子子粒产量。伤根后玉米籽粒产量各伤根处理均高于对照，且大小顺序依次为I2D >I6S> I2S> CK。同时可以看出，干旱情况下伤根确实能提高作物千粒重。5．苗期伤根处理能够提高谷子叶片WUE，而玉米伤根后仅I2D处理的单叶WUE高于对照；除TM和sl处理外，伤根处理提高了谷子和玉米生物量WUE；在土壤含水量为80%田间持水量时，随着伤根程度的加剧和伤根时间的后移，谷子子粒产量WUE下降，伤根不利于谷子WUE的提高；而在50%田间持水量时，前期伤根量适度的处理在不减产甚至增产的情况下还有助于作物子粒产量WUE的提高，而后期伤根的节水效果并不明显。
The experiments were made to analyse the root cutting influence on the crop growth and the water use efficiency by pots and root observing boxes and plots. The results showed:1. The leaf photosynthetic rate was improved by moderate root cutting in seedling stage, and the leaf transpiration rate and stomatal conductance of millet were depressed. But, the leaf photosynthetic rate was depressed and the transpiration rate and stomatal conductance of millet were improved if the root cutting was serious in seedling stage or the root cutting in elongation stage or boot stage.2. The individual plant hight was decreased in Most of treatments of root cutting, and the shrinking rate of leaf area of millet was slower than the check during the bearing anaphase,that is to say, root cutting has definite function to leaf area of millet in preventing premature senility and prolonging ability during the later stage. 15 days later after root cutting, the aboveground biomass of the treatment of root cutting was lower than the check.At the 80% field capacity,the aboveground biomass of millet improved between 1.5~24.7%,and the biomass degraded between 2.9~19.0% at the 50% field capacity.But, three kinds of treatments of root cutting increased the aboveground biomass in maize experiment. 3. Most of millet roots distributed between 0~50cm in the soil profile, the root quantity in root cutting treatments was less than the check between 0~15cm,however, more than the check below the 15cm depth.The total root quantity in root cutting treatment was more than the check. During the short term after root cutting,the root growth was restrained,but later,the root in root cutting treatment was continuing growing,and its root ablity was stretched. Compared the two kinds of root quantity in different water condition,it is easy to produce the new root and hair root in high water condition,and its root growth better than in low water condition evidently.4. At the 80% field capacity,when the root was cutted more seriously and more later,the seed yield of millet dropped;while at the 50% field capacity,moderate root cutting in prophase increased the seed yield (the treatment of "fm" is the highest),but it reduced the seed yield when the root cutting was serious and in boot stage. The seed yields of maize are all increased when they were root cutted,and the order is I2D >I6S> I2S> CK. In all treatments of root cutting at 50% field capacity, thousand grain weight was increased.5. The leaf WUE of millet was increased when root cutting in seedling stage,and only the treatment of I2D of maize increased the leaf WUE; The biomass WUE of millet and maize were increased excepting the root cutting treatments of "TM" and "sl"; At the 80% field capacity, when the root was cutted more seriously and more later,the seed yield WUE of millet were dropped; While at the 50% field capacity, the seed yield WUE of millet was increased when the root cutting is moderate in prophase,and have no reduction of output or increase the production at the same time ,while the benefit of saving water didn"t evidently at the later stage root cutting.
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