[Objective] A field experiment was conducted to illustrate the relationship of milk hne percentage with water content,grain weight and hormone of spring maize to provide a scientific and experimental information for the spring maize maturity selection of different accumulated temperature zone in Heilongjiang province.[Method] ‘ Xianyu335’ and ‘ Xinxin2’ (late maturity varieties),‘ Suiyu’ and ‘ Jidan27 ’ (mid-late maturity varieties) which had different maturities were used as experiment materials,and their milk line percentage,water content,grain weight and hormones were determined.[Result]Compared with late maturity varieties,mid-late maturity varieties could safety ripen,grain milk line formed faster,water content declined more quickly,and the transportation and accumulation of starch were more quickly.At 55 days after anthesis,the milk line percentage of mid-late maturity varieties was 29.37 ％-35.20 ％ bigger than that of late maturity varieties,and water content was 18.52 ％-19.63 ％ lower than that of late maturity varieties.Changes of hormones were similar in varieties but differed in diferent maturity varieties,compared with late maturity varieties,IAA,GA,CTK contents were lower in mid-late maturity varieties,and grains were more mature.ABA content of mid-late maturity varieties was higher in the early stage and lower in the late stage than that of late maturity varieties,which inllustrates mid-late maturity varieties were quickly in launch of grain-filling and had short time of grain-falling period and more dry matter accumulation.[Conclusion] In order to ensure mature of maize and decrease grain water content,mid-late maturity varieties are more suitable for planting at Harbin area.

In order to explore the effects of plant growth regulators on the growth of maize under field conditions,hybrid maize Dongnong253 was used as experimental material.Two plant growth regulators,Migao and KP (the main ingredients were DCPTA and ETH) were sprayed on maize leaf on 9-leaf stage,and the water was control.The leaf photosynthetic enzyme activity,mechanical properties of stem and leaf endogenous hormone contents were measured at the five stages,and the yield measurement and correlation analysis were also been conducted.The results showed Migao and KP treatments increased leaf SPAD,Pn,Rubpc and PEPc.Also two plant growth regulators increased leaf IAA,GA and ZR content and reduced ABA content.Simultaneously improved the dry weight per unit length,puncture strength,transverse fold strength,thrust,also reduce the oblateness and grain water content.The yield of Migao content and KP content were higher than those of CK,which was increased by 6.47％ and 9.23％.There is a significant positive correlation between PEPc,RuBPc,SPAD,Pn,IAA,GA,and ZR and yield,and negative correlation between ABA and yield.

The maize cultivar Zhengdan 958 was choosed as experimental material in this research,and it was treated with foliarly spray with the DCPTA [2-(3,4-dichorophenoxy) triethylamine] (40mg/L) and CCC (C5H13C12 N) (20mg/L) mixture at three leaf stage in order to investigate the effects of the compound mixtures on maize seedlings morphogenesis and leaf physiology on the basis of preliminary experiments.The results showed that,①The plant height of maize seedlings increased 24.94％ treated with the compound mixtures for 8d and the leaf area per plant of maize seedlings increased 200.71 cm2 treated with the mixture for 4d than the control respectively,and both reached a significant level.②The root length,root volume and root surface area of maize seedlings after treated with the mixture for 10d were increased by 12.02％,11.37％ and 21.03％ than control respectively.③The dry weight of maize seedlings treated with the compound mixtures was significantly increased and the shoot ratio higher than the control during the former 4d and less than the control in the following days.It illustrated that the promotion of the compound mixtures for shoots was more obviously.④The content of Chlb increased by 42.76％ and 5.70％ respectively after treated with the compound mixtures for 2d and 10d.⑤The compound mixtures improved leaf cell membrane permeability,increased the proline content in leaves and lowered leaf conductivity.The study provided theoretical and experimental evidence for the application of the DCPTA and CCC mixture to the production.

以玉米东农253、先玉335为试验材料,在盆栽条件下,叶面喷施DCPTA,设置浓度为30mg/L、60mg/L、90mg/L,以清水处理作为对照(CK),喷施处理后分别在3d、6d、9d、12d进行取样分析,以明确DCPTA对寒地不同基因型玉米光合特性以及根系发育的影响.结果表明DCPTA可以显著提高两个玉米品种的生物量、叶片的SPAD值、气孔导度、光合速率、蒸腾速率,降低胞间CO2浓度;可显著提高超氧化物歧化酶(SOD)和过氧化物酶(POD)的活性;显著提高了光系统Ⅱ(PS Ⅱ)反应中初始荧光F0值、最大PS Ⅱ的光能转换效率Fv/Fm.经DCPTA处理,2品种的根系活力及根的总长、表面积、体积和总须根数相比对照也有所提高.试验发现60mg/L的DCPTA处理效果好,而在第9天促进作用达到顶峰.两个品种之间对比发现,DCPTA对先玉335品种喷施后的促进作用更为明显.

Two different plant type corn varieties,the Fenghe1(flat type) and Zhengdan958(compact type),were chosen to study yields and the characteristics of grain nutritional quality under different planting densities.The results showed that the 50 000 plants.hm-2 of Fenghe1 and 60 000 plants.hm-2 of Zhengdan958 reaching the highest yield,which were 9 896 and 10 867 kg.hm-2,respectively.The contents of grain crude protein and ether extract of Fenghe1 decreased with the increasing of plant density,the total starch contents changed conversely.The remarkable negative correlation was shown between the contents of grain protein and ether extract with planting densities,while exposing a remarkable negative correlation of total starch contents and planting densities.The grain protein contents of Zhengdan958 decreased with the plant density increasing,while the ether extract contents increased.The trend of the total starch contents decreased firstly and then increased with the plant density increasing,and a positive correlation appeared between the planting densities and total starch contents.

The paper was to test the yield increase potential of different maize hybrids in Heilongjiang Province. The experiment takes the spreading-leaf Fenghe1 and upright-leaf Zhengdan958as materials. Five different intensity levels were set up to analyze chlorophyll fluorescence parameters and yield. The results showed that the Fo, Fv/Fm and Fv/Fo of upright-leaf maize's decreased ranges are lower than those of spreading- leaf maize, which means spreading- leaf maize is sensitive to increasing planting intensity. With the intensity increases to a certain level, PSII reaction center internal light energy conversion efficiency decreased consequently. And also, PSII potential activity decreased conspicuously. Yield component factors showed that with the 100-seed weight decreasing, the decline of grain number per spike was appearing. 50 000 plants· hm-2of Fenghe1 reaches 9 829 kg· hm-2,which reaching highest output. And Zhengdan 958 reached 11 272 kg· hm-2under 60 000 plants· hm-2.

Three varieties were employed as materials.The experiment studied changes of photosynthetic characteristics under low-temperature stress.The results showed that Pn,Gs,Tr,Fv/Fm,Fv/Fo were decreased with low temperature treatment time and the increasement of level.Ci was decreased in 18 ℃/9 ℃,16 ℃/7 ℃,and decreased in earlier stage after increased in 14 ℃/5 ℃ with treatment time.WUE was increased in earlier stage and after stabilizing.This experiment showed that light absorbed by chlorophyll for photosynthesis could be reduced.The PSⅡ active centers of maize leaves were injured under low temperature stress.The plant is proceeding the self-regulation through adjust Gs,Tr,Ci,WUE.

In order to explore the high yield measures to improve quality in spring wheat production,field experiment was conducted with Longmai 26 and Longmai 33 as the experimental materials with five nitrogen treatments of 45,60,75,90 and 105 kg·hm-2.The effects of nitrogen application on the root physiological activity and grain protein quality of spring wheat were studied.The results showed that,along with the increase of nitrogen application amount,the root activity and grain protein content during the whole growing season increased firstly and then decreased;and the enzyme activities of nitrate reductase and glutamine synthetase of root,the contents of albumin and glutenins of grain increased significantly,while the gliadin content of grain reduced.The appropriate amount of increasing nitrogen was helpful to maintain a high level of root physiological activity at later growing stage,which laid a physiological basis for the improvement of grain protein content and yield of wheat.From the characteristics of root physiological activity,yield and quality,nitrogen application of 90 kg·hm-2 was recommended for Longmai 26 and Longmai 33 as the best.

This experiment was carried out under field conditions in Heilongjiang Province.Two different plant type corn varieties,Fenghe1(flat type) and Zhengdan 958(compact type),were chose to study the characteristics of canopy structure in grain filling stage.The correlation analysis between yield and canopy structure factors was analysized as well.The results indicated the 50000 plants/ hm2 of Fenghe 1 and 60000 plants/ hm2 of Zhengdan 958 reaching the highest yield,which was 9896 kg/hm2 and 10867 kg/hm2 respectively.As well as the leaf area index(LAI) were highest in later filling stage.The trend of the mean foliage inclination angle(MFIA) increased first and then reduced gradually during the whole grain filling stage.Accompanied with the increasing densities,the plant height and ear height were increased,and the stem diameters were decreased at the same time.The leaf area index(LAI) showed a remarkable positive correlation with the spike number per hectare in the former and the middle filling stage,while exposing a remarkable negative correlation with 100-kernel weigh.Furthermore,the experiment showed a positive correlation between the stem diameter and kernel number per spike,and a remarkable positive correlation between the stem diameter and 100-kernel weigh in grain filling stage.

Non plumpness grain has becoming a major restricting factor for the application scale and development space of triticale.Triticale varieties Dongnong 8809 and Dongnong 95-6654 were used as materials,the grain dry matter accumulation,grain-filling rate and yield of triticale were investigated under the application of exogenous GA3 in order to understand the effects on grain-filling and yield under the regulation of GA3 at anthesis.The results indicated that appropriate amount of GA3 at anthesis increased the grain-filling rate of triticale,accelerated the grain-filling process and promoted the transportion of dry matter to grain,then increased the grain weight and yield.In this test,the concentration of GA3 20 mg·L-1 was the best.

In order to evaluate effects of planting density on the ear leaf soluble sugar content and the starch accumulation in two plant types maize cultivars,field experiments were carried out in 2010 by using two plant types maize cultivars,Zhengdan958(a compact maize cultivar),and Fenghe1(a flat type maize cultivar).The results indicated that the ear leaf soluble sugar content,the amylose content,the amylopectin content and the starch content in grains of two plant types maize cultivars all increased in grain filling stage.During the later stage,Zhengdan 958 and Fenghe1 were the highest content of soluble sugar in the lowest density(40000 plants/hm2,50000 plants/hm2),respectively;amylose content of Fenghe1 in 60000 plants/hm2,amylopectin content,the starch content and total starch yield in 50000 plants/hm2 treatments were the highest,the amylose content,the amylopectin and the totol starch content of Zhengdan958 were the highest in 60000 plants/hm2 treatments.

Using three maize varieties,through pot experiment to study the change of electric conductivity and fluorescence parameters under low-temperature stress.The results showed that the resistance of three varieties is Jin Yu 5Xing Ken 3Ji Dan 198.Membrane leakage and minimum chlorophyll fluorescence(F0) of the three varieties were increased;the Fv/Fm,Fv/F0,and NPQ were declining with low-temperature treatment time.This experiments show that light absorbed by chlorophyll for photosynthesis can be reduced.The PSⅡactive centers of maize leaves were injured under low-temperature stress.

The experiment with two cultivars and three planting densities in the field was conducted to establish quantitative indicators for high yielding cultivars.The randomized block design was employed with main plot of plant density(low,medium,and high respectively).The result showed that the high-yielding canopy structure and distribution of light radiation internal canopy structure were obtained under medium densities of the two cultivars.Photosynthetically active radiation(PAR),transmission coefficient for radiation penetration decreased with the increase of plant density in canopy.The range distribution of leaves were greater,mean foliage inclination angle(MFIA) were highest under high densities,such as Zhengdan958 were 0.35 and 78.48,and Fenghe1 were 0.33 and 61.25 in silking stage. The later growth stages leaf area index(LAI) was smallest,range distribution of leaves and photosynthetically active radiation( PAR) were the highest under low densities Results confirmed that proper planting density can establish high-yielding canopy structure and improve population light environment and yield in maize.As for Zhengdan958 and Fenghe1,population average extinction coefficient was highest,reaching 0.69-0.74 in silking stage and 0.62-0.67 in mid-filling stage under medium density.From silking stage to maturity,the leaf area index(LAI) of zhengdan958 and Fenghe1declined to the lowest under medium density,reaching 17% and 27% respectively,which giving a good foundation for the photosynthesis production and yield increasing.

In order to provide scientific and theoretical basis for the application of exogenous regulator in the high yield and high quality cultivation of triticale,Dongnong 8809 and Dongnong 95-6654 were used as materials,the effects of spraying GA3 on the photosynthetical system of flag leaf and yield of triticale were investigated.The results indicated that the photosynthetic function of flag leaf was enhanced after spraying GA3 through the increase of Chlorophyll a,Chlorophyll b and Chlorophyll(a+b) contents;the improvement of Fm,Fm/Fv and qP,and the reduction of qN,Finally the thousand seed weight and yield of wheat were increased by spraying GA3.The results also indicated the best concentration for spraying GA3 is 20 mg·L-1.

Investigation on improving the training mechanism for the undergraduate research abilities is vital to accelerating the higher education reform,especially in the area of the cultivation of innovative talents.Based on the definition of undergraduate scientific research and the analysis on the current situation of training scientific research abilities,the paper reasserted the necessity and principles of perfecting the training system of scientific research abilities for the undergraduate students from the aspects of society,university,and students,and offered some counter-measures.