In order to determine the most suitable sowing periods for maize in the cold area of Harbin City,the field test method was adopted.From 2018 to 2019,the main maize variety Xianyu 696 which was planted in Harbin City,H...In order to determine the most suitable sowing periods for maize in the cold area of Harbin City,the field test method was adopted.From 2018 to 2019,the main maize variety Xianyu 696 which was planted in Harbin City,Heilongjiang Province,was used as the test material for the six-sowing-period treatment experiments.The sowing period settings were as the followings:April 20(T1),April 24(T2),April 27(T3),May 4(T4),May 11(T5)and May 18(T6).In the experiment,the effects of different sowing periods on the growth and development,yields and quality of maize were studied.The results showed that the maize through T1 treatment had the longest growth period,the lowest height and the highest ear height,and the highest grain protein content.The maize through T6 treatment had the highest height and ear height,as well as the highest starch and oil content.And the grain crude fat,soluble protein,soluble sugar and the moisture content increased and then decreased with the delay of the sowing period.The maize through T4 treatment had the highest content of soluble protein.However,other quality indicators and the number of rows,the length of the bald tip,the number of grains per spike and the weight of 100 grains first increased and then decreased with the delay of the sowing period.The dry matter accumulation through T4 treatment was significantly higher than the ones through five treatments,and the 100-kernel weight and other ear-grain traits were the highest,the maizes through T4 treatment increased the yield by 21.54%compared with that through T1 treatment.Thus,the most suitable sowing period for the maize in the cold area of Harbin City was from May 4 to May 11.It provided technical supports for guiding maize planting in the cold area of Harbin City.展开更多
This paper analyzed the extreme climatic characteristics of maize in Heilongjiang Province during different growth periods using the climate data and maize yield data from 1961 to 2020,and applied the principal compon...This paper analyzed the extreme climatic characteristics of maize in Heilongjiang Province during different growth periods using the climate data and maize yield data from 1961 to 2020,and applied the principal component analysis to analyze the extent of different extreme climatic events affecting maize yield.The results showed that the extreme cold events showed a decreasing trend,and the extreme warm events showed an increasing trend,and the trend of extreme precipitation change was not obvious.Maize yield was negatively correlated with TN10p(cold nights),TX10p(warm days)and T8(days below the lower temperature limit),and positively correlated with TN90p(warm nights).T34(days above the upper temperature limit)and TX90p(warm days)during the tasseling-milking period were negatively correlated with the maize yield,and this part was concentrated in the southern part of Heilongjiang Province.The maize yield was positively correlated with the extreme precipitation during the seedling period and negatively correlated with the extreme precipitation during the filling-maturity period of maize,but the correlations were not significant.The effects of extreme weather events on maize yield were higher during the seedling and the filling-maturity periods than those during the jointing-tasseling and the tasseling-milking periods.The effects of extreme precipitation on the maize yield were less than those of the extreme temperature during different growth periods in all regions,but the effects of the extreme precipitation on maize yield were significantly higher in the Songnen Plain than those in other regions.There were regional differences in the impact of climate extremes on maize during different growth periods.The area with the greater impact of climate extremes during the seedling period was the Songnen Plain,the areas with the greater impact of climate extremes during the jointing-tasseling period were the northern part of the Sanjiang Plain,and the areas with the greater impact of climate extremes during the filling-maturity period were the Lesser Khingan Mountains and the semi-mountainous areas of Mudanjiang.展开更多
By two years （2007-2008） located fertilizer experiment, the effect of long-term combined application of organic and inorganic fertilizers on black soil fertility and crop yield was investigated in Shuangcheng City, ...By two years （2007-2008） located fertilizer experiment, the effect of long-term combined application of organic and inorganic fertilizers on black soil fertility and crop yield was investigated in Shuangcheng City, Heilongjiang Province. The results showed that the combined application of organic and inorganic fertilizers could increase the organinc matter, alkaline nitrogen, available phosphorus and available potassium. At the same time, the increasing application of organic fertilizer could reduce the soil bulk density and improve the field moisture capacity. Field moisture capacity and organic matter of the combined application of high quantities of organic manure and inorganic fertilizers AtB5 treatment increased the fhstest, organic matter increased by 3.33 g. kg and field moisture capacity increased by 11.25% than the beginning of the experiment. Under the same fertilization, the combined application of organic and inorganic fertilizers＇ increasing production range was higher than the single chemical fertilizers＇ which was from 0.8% to 9.4%. The results showed that the combined application of organic and inorganic fertilizers could increase the nutrient contents of soil and also was the highest productivity contribution to black soil fertility. It was the best fertilization structure of increasing productivity level and improving the soil fertility.展开更多
DCPTA （2-diethylaminoethyl-3, 4-dichlorophenylether） is a new plant regulator which can be used to regulate growth and development for crops. Experiments on maize seedlings were conducted in the growth chamber to st...DCPTA （2-diethylaminoethyl-3, 4-dichlorophenylether） is a new plant regulator which can be used to regulate growth and development for crops. Experiments on maize seedlings were conducted in the growth chamber to study the effects of foliar applied DCPTA. The plant pots were placed in a completely randomized design with three replicates. The maize seedlings were treated with 0 mg·L-1 （control）, 20 mg·L-1 and 40 mg·L-1 DCPTA solution. The effects of DCPTA on the photosynthetic characteristics （photosynthesis, stomata conductance, intercellular CO2, and transpiration rate）, related physiological characteristics （contents of soluble sugar and starch）, chlorophyll fluorescence parameters （Fo, Fro, Fv/Fm, Fv/Fo, qP, and qN） and the weight of dry matter in maize seedling were studied. The results showed that DCPTA enhanced photosynthesis of maize seedling. In general, photosynthetic rate in leaves was significantly promoted through spraying DCPTA solution, and 40 rag＂ L~ DCPTA was found to be the best concentration for maize. The relationship between stomata conductance and transpiration rate in maize leaves could be described as linear. With regard to the chlorophyll fluorescence parameters, our fmdings showed that 40 mg·L-1 DCPTA in maize seedling caused an increase in Fm, Fv/Fm, Fm/Fo, qP and a decrease in Fo and qN at some time points checked. It is suggested that DCPTA increased photosynthetic rate by raising both the content of chlorophyll and activities of PSII and the contents of sugar and starch. Compared with the control, the treated maize seedling caused an increase in plant height, root length, shoot dry mass, root dry mass, or the total （root plus shoot） dry mass.展开更多
At the beginning of silking, maize production began to form, but leaves started senescence and photosynthetic capacity decreased at this time, all of those severely restricted the formation of the production. In order...At the beginning of silking, maize production began to form, but leaves started senescence and photosynthetic capacity decreased at this time, all of those severely restricted the formation of the production. In order to study the effects of exogenous substances on the process of leaf senescence, 40 mg. L-1 DCPTA and 20 mg. L-1 CCC were mixed in the research. When the maize grew to the six expanded leaves stage, 10 mL compound mixtures （TR） were sprayed on both sides of leaves for per plant, and the control was treated with water （CK）. Three plants were selected randomly for determination of physiological index at 10, 20, 30, 40 and 50 days after silking. The results showed that TR could increase the chlorophyll content significantly, FvFm, Fv/F0 and Y（Ⅱ） values of TR were higher than those of CK while F0 values were opposite. Compared with CK, TR increased SOD and POD activities and soluble protein content, and reduced MDA content. Correlation analysis showed that chlorophyll content had negative correlation with F0, and MDA content had negative correlation with other indexes. Compared with CK, TR reduced the negative correlation effect between chlorophyll content and MDA, increased the positive correlation effect between chlorophyll content and Fv/Fm, SOD, PODI and soluble protein. The study provided theoretical and experimental evidence for the application of the compound mixtures of DCPTA and CCC to the production.展开更多
Three varieties were employed as materials to study changes of photosynthetic traits under low-temperature stress. The results showed that Pn, Gs and Tr decreased under low-temperature treatment. Ci decreased under lo...Three varieties were employed as materials to study changes of photosynthetic traits under low-temperature stress. The results showed that Pn, Gs and Tr decreased under low-temperature treatment. Ci decreased under low-temperature treatment 18℃/ 9℃, and 16℃/7℃, and it decreased in earlier stage after increased under 14℃/5℃. WUE was increased in earlier stage and after stabilized. The order of the three varieties of cold resistance were Jinyu 5〉Xingken 3〉Jidan 198. They could make self-regulation through adjusting Gs, Tr, Ci and WUE.展开更多
In order to explore the response of maize phosphorus absorption to the appropriate proportion of organic fertilizer substitution for reduced chemical fertilizer,a field experiment with eight treatments was conducted i...In order to explore the response of maize phosphorus absorption to the appropriate proportion of organic fertilizer substitution for reduced chemical fertilizer,a field experiment with eight treatments was conducted in 2018.The eight treatments in the trial were:(1)CK;(2)M0+F;(3)M1+F1;(4)M1+F2;(5)M2+F1;(6)M2+F2;(7)M3+F1 and(8)M3+F2.In these treatments,M0,M1,M2 and M3 were organic fertilization of 0,15(low),30(medium)and 45(high)m3•hm-2,respectively.F1 and F2 indicated 20%and 40%reduction of conventional chemical fertilization.The soil nutrient content,phosphorus accumulation,dry weight,yield and yield components of maize were analyzed.The results showed that the phosphorus accumulation of maize stalks and leaves were 3.30%-43.17%and 10.98%-84.95%higher in M3+F1 treatment(20%reduction of chemical fertilizer with organic fertilizer of 45 m3•hm-2)than those in the conventional treatment(M0+F)during the maize reproductive period.At R2 stage,stalk and shoot P accumulation of M3+F1 treatment were 24.67%-43.18%and 20.34%-25.19%higher than other treatments,respectively.At V12 stage,leaf P accumulation of M3+F1 increased by 84.95%compared with other treatments.The maize yield of M3+F1 was significantly higher than that of other treatments,even though the partial productivity of the total phosphorus fertilizer of M3+F2 was the highest in the treatments.It could be found that the substitution of organic fertilizer for chemical fertilizer improved crop yield,phosphorus fertilizer efficiency and accumulation.M3+F1 treatment had the most positive effects on improving maize phosphorus accumulation and yield.展开更多
Many reviews and evaluations of contract farming and its importance for small-scale farmers in the developing nations have been conducted. While some scholars opined that contractual terms were unfavourable to farmers...Many reviews and evaluations of contract farming and its importance for small-scale farmers in the developing nations have been conducted. While some scholars opined that contractual terms were unfavourable to farmers, others considerd them as being beneficial to them. These contrasting views were not likely to discourage it since it provided encouragement for farmers＇ involvement in markets. It was therefore worthwhile to investigate previous experiences with the aim of improving on it. This study investigated contract farming entered into by farmers in Delta State of Nigeria and livestock feed companies with the objective of seeking ways to make such contractual agreements beneficial to small-scale farmers. The study utilized convergence of science approach. The study unveiled the constraints experienced by farmers and they included technical and institutional challenges. The technical problem was the planting date, while the institutional problem was the contractual arrangements. It was recommended that all the stakeholders in the contract should converge and negotiate technological adoptions of the improved maize varieties; contract needed to be clearly def＇med and risks and uncertainties should be parts of the contract; scientific investigations should be carded out to determine the best planting date; and there was need for legislation to particularly protect farmers in contract farming.展开更多
In order to make the relevant risk departments and the agricultural producers have a clearer understanding of maize cold damage, the data of daily average temperature of 83 meteorological stations in Heilongjiang Prov...In order to make the relevant risk departments and the agricultural producers have a clearer understanding of maize cold damage, the data of daily average temperature of 83 meteorological stations in Heilongjiang Province from 1986 to 2015, and the risk assessment model of maize cold damage in northeast China were used, and the risk index values of maize cold damage in Heilongjiang Province from 1986 to 2015 were calculated. And according to the risk index values, Heilongjiang Province was divided into five risk areas. The results showed that the high risk areas and the sub-high risk areas of maize cold damage in Heilongjiang Province in recent 30 years were in Daqing and Suihua cities, the medium risk areas were located in the center of the Songnen Plain and other regions, the sub-low risk areas were located in the Songnen Plain, and most of the rest were the low risk areas.展开更多
common maize synthetic rate（ Photosynthetic characteristics were probed by sweet maize, waxy maize, high starch maize and The results revealed that leaf area index （LAI）, chlorophyll a content, chlorophyll b cont...common maize synthetic rate（ Photosynthetic characteristics were probed by sweet maize, waxy maize, high starch maize and The results revealed that leaf area index （LAI）, chlorophyll a content, chlorophyll b content,photo-PR） showed single peak curve at the whole growth stage. The stages of peak were different according to different varieties. NEAUS4 had the lowest peak and while SIDAN 19 had the highest among all stages. Ratio of chlorophyll a to b was low at seedling stage, reached the peak atjointing stage and then declined. SIDAN 19 had the lower level at the last stages.展开更多
The results indicate that high protoplast quality corresponds to high stress tolerance. The damage of cell membrane is one of the important mechanisms of stress. The protective enzyme system(superoxide dismutase.perox...The results indicate that high protoplast quality corresponds to high stress tolerance. The damage of cell membrane is one of the important mechanisms of stress. The protective enzyme system(superoxide dismutase.peroxidase and catalase) plays an important role in stress tolerance. In the research of hormone it is suggested that ABA can induce chilling torlerance, and the mechanism may correlate with the special gene expression.展开更多
The appropriate density of the hybrids with different plant morphotypes and grainyield of main maize hybrids in Henan province under different conditions and in different placeshave been studied for many years.The res...The appropriate density of the hybrids with different plant morphotypes and grainyield of main maize hybrids in Henan province under different conditions and in different placeshave been studied for many years.The results indicalte that all the light intensity in middle andlow part of the plant,the single leaf weight(SLW) and the photosynthetic intensity decrease re-markably with the increase of plant density and leaf area index(LAI),and that all the charactersof the sirgle plant yield becorne inferior with different magnitudes.But the seriousness is slighterfor compact type hybrids than that for spread ones.Under high yield condition,the desirabledensity is 4250 to 5000 plants per mu(666. 67m^2)for compact maize hybrids and 3300 to 3500plants for spread ones.The yield differences between the two kinds of hybrid vary with the yieldlevels.展开更多
Soil erosion induced by inappropriate tillage remains a serious problem on many agricultural fields in the humid tropics. Studies were conducted between 2004 and 2006, on an Alfisol in Ogbomoso in the Southern Guinea ...Soil erosion induced by inappropriate tillage remains a serious problem on many agricultural fields in the humid tropics. Studies were conducted between 2004 and 2006, on an Alfisol in Ogbomoso in the Southern Guinea Savanna of Nigeria to evaluate the effectiveness of Vetiver Grass(Vetiveria nigritana) Strips(VGS) under different tillage systems. The experiment was split-plot laid out in a randomized complete block design with two replications on 6% slope with 18 runoff plots. Main plot treatments were tillage systems; Manual Clearing(MC), Ploughing(P) and Ploughing plus Harrowing(PH). Subplot treatments were VGS spaced at intervals of 5 m(eight strips) and 10 m(four strips) with the control(no-vetiver). Runoffs and soil losses were collected after each major storm. Chemical analyses of eroded sediments and runoff were determined. Data were analyzed using ANOVA at p<0.05. The results showed that tillage had no significant reduction in runoffs and soil losses, but they were reduced with MC compared with P and PH. Mean total runoff on 5 and 10 m VGS plots were significantly(p<0.05) lower than that of the control by 74.4% and 45.0%, respectively. Corresponding soils loss on 5 and 10 m VGS plots were 27.1% and 53.5%, respectively. Mean NO3-N levels in runoff water were lower under PH plots than those under MC plots by 79.0% and 66.5%, respectively in 2004 and 2006 growing seasons. VGS spaced at 5 m significantly(p<0.05) reduced NO3-N loss than the control by 108.8% in 2004. Nutrients loads of eroded sediments were consistently higher for the control(no-vetiver) plots and least for 5 m VGS plot. Carbon, nitrogen and phosphorus contents of eroded sediments were 90%-92.4%, 83%-83.6% and 97%-97.8%, respectively, and were lower on 5 m than other treatments. Maize grain yield was significantly(p<0.05) affected by both tillage and VGS spacing only in 2005 growing season. P plot produced higher grain yield than MC and PH by 79.9% and 99.1%, respectively. Also, grain yield on VGS plot was significantly(p<0.05) higher on 5 and 10 m VGS plots than the control by 82.2% and 85.4%, respectively. The significant beneficial effect of PH in producing higher yields was dwarfed by the potential danger of soil erosion in the absence of a soil erosion control measure. The results showed that a balance needed to be struck between mechanical clearance and protective measure against soil erosion.展开更多
The two maize varieties,Yuanzheng 808(astrictive type) and Sidan 19(explanate type),were cultured in pots.There were six treatments which the proportion of NO 3 - N and NH 4 + N were 1∶0 (treatment 1),2∶1(tr...The two maize varieties,Yuanzheng 808(astrictive type) and Sidan 19(explanate type),were cultured in pots.There were six treatments which the proportion of NO 3 - N and NH 4 + N were 1∶0 (treatment 1),2∶1(treatment 2),1∶1(treatment 3),1∶2(treatment 4),0∶1(treatment 5) and CK(no nitrogen) respectively.After emergence of seedings,the samples were picked up per 20 days in the growth period and measured chlorophyll contents,nitrate reductase(NR) activity,the weight of dry matter and single plant seed yield respectively.The result showed that enhanced ammonium nutrition (EAN) may increase chlorophyll content,dry matter weight and single plant seed yield.But there was a difference between varieties.To Yuanzheng 808,treatment 2 was the highest yield in all treatments;but treatment 4 was the highest yield to Sidan 19.展开更多
Aiming at less and un-uniform distribution rainfall problems, the serious draught in spring, low crop production and water efficiency in sandy soil area of Heilongjiang Province, the experiment of alternative furrow i...Aiming at less and un-uniform distribution rainfall problems, the serious draught in spring, low crop production and water efficiency in sandy soil area of Heilongjiang Province, the experiment of alternative furrow irrigation was conducted in Dumeng County in 2009. The purpose of the experiment was to find the water consumption law and its influence on maize yield. The results showed that the highest water consumption was during the heading stage and the highest daily consumption of water was during the filling stage. The stimulation effect of alternative furrow irrigation on yield was obvious in the appropriate irrigation level. The best irrigation pattern for the highest yield was as follows： the seedling stage was 325 m3. hm^-2; the jointing stage was 400 m3-hm^-2; and the filling stage was 288 m3- hm-2. The water consumption during each growing period was that the seedling was 38.85 mm; the jointing was 108.11 mm; the heading was 124.39 ram; the filling was 88.96 ram; the milk was 60.21 ram; and the harvesting was 47.89 mm.展开更多
Southern corn rust(SCR) caused by Puccinia polysora Underw and maize stalk rot caused by Pythium inflatum Matthews(MSR-2) are two destructive diseases of maize(Zea mays L.) in China.Our previous studies indicated that...Southern corn rust(SCR) caused by Puccinia polysora Underw and maize stalk rot caused by Pythium inflatum Matthews(MSR-2) are two destructive diseases of maize(Zea mays L.) in China.Our previous studies indicated that maize inbred line Qi319 is highly resistant to SCR but susceptible to MSR-2,while inbred line 1145 is highly resistant to MSR-2 but susceptible to SCR.The SCR resistant gene(RppQ) in Qi319 and MSR-2 resistant gene(Rpi1) in 1145 have been mapped on chromosome 10 and 4 respectively.In this research,through marker-assisted selection(MAS) with the molecular markers,bnlg1937 tightly linked to Rpi1 and phi041 tightly linked to RppQ,pyramid breeding of the two kinds of disease resistant genes were carried out from the year of 2003 to 2007.Two homozygotic inbred lines of F5 generation,DR94-1-1-1 and DR36-1-1-1 were identified.MAS result suggested DR94-1-1-1 and DR36-1-1-1 contained the two resistance genes RppQ and Rpi1.Field inoculation tests confirmed their high resistance to the two diseases.In addition,field investigation indicated that the two selected inbred lines,particularly DR94-1-1-1,had excellent agronomic traits such as plant height,ear height and yield-relating traits including ear length,ear diameter,ear weight,kernels per ear,kernels per row and kernel weight per ear.The two selected inbred lines DR94-1-1-1 and DR36-1-1-1 can either be directly developed into commercial variety or used as immediate donors of SCR and MSR resistance breeding programs in maize.展开更多
A pot culture trial was conducted to investigate the changes of the biomass and acid phosphatase （APase） activity in 10 maize lines under low-P stress. P-deficiency significantly decreased the biomass, but induced t...A pot culture trial was conducted to investigate the changes of the biomass and acid phosphatase （APase） activity in 10 maize lines under low-P stress. P-deficiency significantly decreased the biomass, but induced the significant enhancement of the APase activity. Since P-deficiency had smaller effects on the low-P tolerant maize lines compared with P-sensitive lines, it was demonstrated that differences of tolerance to P-deficiency existed among 10 different maize lines. In addition, the relative biomass and APase activity changed during the vegetative stage of development, and there existed a significant correlation between the biomass and APase activity under low-P stress. These results suggest that the biomass and APase activity can be regarded as indicative traits of maize lines for tolerance to low-P stress at seedling stage.展开更多
基金Supported by"Thirteenth Five-Year"Key Research and Development Project Sub-project"Integration and Demonstration of Spring maize Solar and Hot Water Resources Utilization Technology in Humid Areas of Heilongjiang Province"(2018YFD0300103-1)。
文摘In order to determine the most suitable sowing periods for maize in the cold area of Harbin City,the field test method was adopted.From 2018 to 2019,the main maize variety Xianyu 696 which was planted in Harbin City,Heilongjiang Province,was used as the test material for the six-sowing-period treatment experiments.The sowing period settings were as the followings:April 20(T1),April 24(T2),April 27(T3),May 4(T4),May 11(T5)and May 18(T6).In the experiment,the effects of different sowing periods on the growth and development,yields and quality of maize were studied.The results showed that the maize through T1 treatment had the longest growth period,the lowest height and the highest ear height,and the highest grain protein content.The maize through T6 treatment had the highest height and ear height,as well as the highest starch and oil content.And the grain crude fat,soluble protein,soluble sugar and the moisture content increased and then decreased with the delay of the sowing period.The maize through T4 treatment had the highest content of soluble protein.However,other quality indicators and the number of rows,the length of the bald tip,the number of grains per spike and the weight of 100 grains first increased and then decreased with the delay of the sowing period.The dry matter accumulation through T4 treatment was significantly higher than the ones through five treatments,and the 100-kernel weight and other ear-grain traits were the highest,the maizes through T4 treatment increased the yield by 21.54%compared with that through T1 treatment.Thus,the most suitable sowing period for the maize in the cold area of Harbin City was from May 4 to May 11.It provided technical supports for guiding maize planting in the cold area of Harbin City.
基金Supported by the"Thirteenth Five-Year"Key Research and Development Project Sub-project"Integration and Demonstration of Spring Maize Solar and Hot Water Resources Utilization Technology in Humid Areas of Heilongjiang Province"(2018YFD0300103-1)。
文摘This paper analyzed the extreme climatic characteristics of maize in Heilongjiang Province during different growth periods using the climate data and maize yield data from 1961 to 2020,and applied the principal component analysis to analyze the extent of different extreme climatic events affecting maize yield.The results showed that the extreme cold events showed a decreasing trend,and the extreme warm events showed an increasing trend,and the trend of extreme precipitation change was not obvious.Maize yield was negatively correlated with TN10p(cold nights),TX10p(warm days)and T8(days below the lower temperature limit),and positively correlated with TN90p(warm nights).T34(days above the upper temperature limit)and TX90p(warm days)during the tasseling-milking period were negatively correlated with the maize yield,and this part was concentrated in the southern part of Heilongjiang Province.The maize yield was positively correlated with the extreme precipitation during the seedling period and negatively correlated with the extreme precipitation during the filling-maturity period of maize,but the correlations were not significant.The effects of extreme weather events on maize yield were higher during the seedling and the filling-maturity periods than those during the jointing-tasseling and the tasseling-milking periods.The effects of extreme precipitation on the maize yield were less than those of the extreme temperature during different growth periods in all regions,but the effects of the extreme precipitation on maize yield were significantly higher in the Songnen Plain than those in other regions.There were regional differences in the impact of climate extremes on maize during different growth periods.The area with the greater impact of climate extremes during the seedling period was the Songnen Plain,the areas with the greater impact of climate extremes during the jointing-tasseling period were the northern part of the Sanjiang Plain,and the areas with the greater impact of climate extremes during the filling-maturity period were the Lesser Khingan Mountains and the semi-mountainous areas of Mudanjiang.
基金Supported by Black Soil Conservation Tillage and Oriented Cultivation Technology Research (GB06B107-1)Innovation Fund of Northeast Agricultural University (CXP7003-3-3)+1 种基金Northeast Agricultural University and the Scientific Research Fund of Heilongjiang Province to Black CollegesUniversities Cold Key Laboratory of Utilization and Protection of Open-funded Projects (GXS08-5)
文摘By two years （2007-2008） located fertilizer experiment, the effect of long-term combined application of organic and inorganic fertilizers on black soil fertility and crop yield was investigated in Shuangcheng City, Heilongjiang Province. The results showed that the combined application of organic and inorganic fertilizers could increase the organinc matter, alkaline nitrogen, available phosphorus and available potassium. At the same time, the increasing application of organic fertilizer could reduce the soil bulk density and improve the field moisture capacity. Field moisture capacity and organic matter of the combined application of high quantities of organic manure and inorganic fertilizers AtB5 treatment increased the fhstest, organic matter increased by 3.33 g. kg and field moisture capacity increased by 11.25% than the beginning of the experiment. Under the same fertilization, the combined application of organic and inorganic fertilizers＇ increasing production range was higher than the single chemical fertilizers＇ which was from 0.8% to 9.4%. The results showed that the combined application of organic and inorganic fertilizers could increase the nutrient contents of soil and also was the highest productivity contribution to black soil fertility. It was the best fertilization structure of increasing productivity level and improving the soil fertility.
基金Supported by the National Natural Science Foundation of China(31201164)the Program of Science and Technology of Education Department of Heilongjiang Province(12521036)+2 种基金China Postdoctoral Science Foundation(2012M511434)Heilongjiang Province Postdoctoral Science Foundation(LBH-Z12036)the Doctoral Starting Up Foundation of Northeast Agricultural University(2012RCB01)
文摘DCPTA （2-diethylaminoethyl-3, 4-dichlorophenylether） is a new plant regulator which can be used to regulate growth and development for crops. Experiments on maize seedlings were conducted in the growth chamber to study the effects of foliar applied DCPTA. The plant pots were placed in a completely randomized design with three replicates. The maize seedlings were treated with 0 mg·L-1 （control）, 20 mg·L-1 and 40 mg·L-1 DCPTA solution. The effects of DCPTA on the photosynthetic characteristics （photosynthesis, stomata conductance, intercellular CO2, and transpiration rate）, related physiological characteristics （contents of soluble sugar and starch）, chlorophyll fluorescence parameters （Fo, Fro, Fv/Fm, Fv/Fo, qP, and qN） and the weight of dry matter in maize seedling were studied. The results showed that DCPTA enhanced photosynthesis of maize seedling. In general, photosynthetic rate in leaves was significantly promoted through spraying DCPTA solution, and 40 rag＂ L~ DCPTA was found to be the best concentration for maize. The relationship between stomata conductance and transpiration rate in maize leaves could be described as linear. With regard to the chlorophyll fluorescence parameters, our fmdings showed that 40 mg·L-1 DCPTA in maize seedling caused an increase in Fm, Fv/Fm, Fm/Fo, qP and a decrease in Fo and qN at some time points checked. It is suggested that DCPTA increased photosynthetic rate by raising both the content of chlorophyll and activities of PSII and the contents of sugar and starch. Compared with the control, the treated maize seedling caused an increase in plant height, root length, shoot dry mass, root dry mass, or the total （root plus shoot） dry mass.
基金Supported by the National Natural Science Foundation of Youth Science Foundation(31201164)Northeast Agricultural University Doctor Started Foundation(2012RCB01)+1 种基金China Postdoctoral Foundation(2012M511434)Project of National Non-profi t Institute Fund(BSRF201405)
文摘At the beginning of silking, maize production began to form, but leaves started senescence and photosynthetic capacity decreased at this time, all of those severely restricted the formation of the production. In order to study the effects of exogenous substances on the process of leaf senescence, 40 mg. L-1 DCPTA and 20 mg. L-1 CCC were mixed in the research. When the maize grew to the six expanded leaves stage, 10 mL compound mixtures （TR） were sprayed on both sides of leaves for per plant, and the control was treated with water （CK）. Three plants were selected randomly for determination of physiological index at 10, 20, 30, 40 and 50 days after silking. The results showed that TR could increase the chlorophyll content significantly, FvFm, Fv/F0 and Y（Ⅱ） values of TR were higher than those of CK while F0 values were opposite. Compared with CK, TR increased SOD and POD activities and soluble protein content, and reduced MDA content. Correlation analysis showed that chlorophyll content had negative correlation with F0, and MDA content had negative correlation with other indexes. Compared with CK, TR reduced the negative correlation effect between chlorophyll content and MDA, increased the positive correlation effect between chlorophyll content and Fv/Fm, SOD, PODI and soluble protein. The study provided theoretical and experimental evidence for the application of the compound mixtures of DCPTA and CCC to the production.
基金Supported by the Science and Technology Foundation(2008BADB3B09-03)
文摘Three varieties were employed as materials to study changes of photosynthetic traits under low-temperature stress. The results showed that Pn, Gs and Tr decreased under low-temperature treatment. Ci decreased under low-temperature treatment 18℃/ 9℃, and 16℃/7℃, and it decreased in earlier stage after increased under 14℃/5℃. WUE was increased in earlier stage and after stabilized. The order of the three varieties of cold resistance were Jinyu 5〉Xingken 3〉Jidan 198. They could make self-regulation through adjusting Gs, Tr, Ci and WUE.
基金Supported by the National Key Research and Development Plan Project(2017YFD0201803)。
文摘In order to explore the response of maize phosphorus absorption to the appropriate proportion of organic fertilizer substitution for reduced chemical fertilizer,a field experiment with eight treatments was conducted in 2018.The eight treatments in the trial were:(1)CK;(2)M0+F;(3)M1+F1;(4)M1+F2;(5)M2+F1;(6)M2+F2;(7)M3+F1 and(8)M3+F2.In these treatments,M0,M1,M2 and M3 were organic fertilization of 0,15(low),30(medium)and 45(high)m3•hm-2,respectively.F1 and F2 indicated 20%and 40%reduction of conventional chemical fertilization.The soil nutrient content,phosphorus accumulation,dry weight,yield and yield components of maize were analyzed.The results showed that the phosphorus accumulation of maize stalks and leaves were 3.30%-43.17%and 10.98%-84.95%higher in M3+F1 treatment(20%reduction of chemical fertilizer with organic fertilizer of 45 m3•hm-2)than those in the conventional treatment(M0+F)during the maize reproductive period.At R2 stage,stalk and shoot P accumulation of M3+F1 treatment were 24.67%-43.18%and 20.34%-25.19%higher than other treatments,respectively.At V12 stage,leaf P accumulation of M3+F1 increased by 84.95%compared with other treatments.The maize yield of M3+F1 was significantly higher than that of other treatments,even though the partial productivity of the total phosphorus fertilizer of M3+F2 was the highest in the treatments.It could be found that the substitution of organic fertilizer for chemical fertilizer improved crop yield,phosphorus fertilizer efficiency and accumulation.M3+F1 treatment had the most positive effects on improving maize phosphorus accumulation and yield.
文摘Many reviews and evaluations of contract farming and its importance for small-scale farmers in the developing nations have been conducted. While some scholars opined that contractual terms were unfavourable to farmers, others considerd them as being beneficial to them. These contrasting views were not likely to discourage it since it provided encouragement for farmers＇ involvement in markets. It was therefore worthwhile to investigate previous experiences with the aim of improving on it. This study investigated contract farming entered into by farmers in Delta State of Nigeria and livestock feed companies with the objective of seeking ways to make such contractual agreements beneficial to small-scale farmers. The study utilized convergence of science approach. The study unveiled the constraints experienced by farmers and they included technical and institutional challenges. The technical problem was the planting date, while the institutional problem was the contractual arrangements. It was recommended that all the stakeholders in the contract should converge and negotiate technological adoptions of the improved maize varieties; contract needed to be clearly def＇med and risks and uncertainties should be parts of the contract; scientific investigations should be carded out to determine the best planting date; and there was need for legislation to particularly protect farmers in contract farming.
文摘In order to make the relevant risk departments and the agricultural producers have a clearer understanding of maize cold damage, the data of daily average temperature of 83 meteorological stations in Heilongjiang Province from 1986 to 2015, and the risk assessment model of maize cold damage in northeast China were used, and the risk index values of maize cold damage in Heilongjiang Province from 1986 to 2015 were calculated. And according to the risk index values, Heilongjiang Province was divided into five risk areas. The results showed that the high risk areas and the sub-high risk areas of maize cold damage in Heilongjiang Province in recent 30 years were in Daqing and Suihua cities, the medium risk areas were located in the center of the Songnen Plain and other regions, the sub-low risk areas were located in the Songnen Plain, and most of the rest were the low risk areas.
文摘common maize synthetic rate（ Photosynthetic characteristics were probed by sweet maize, waxy maize, high starch maize and The results revealed that leaf area index （LAI）, chlorophyll a content, chlorophyll b content,photo-PR） showed single peak curve at the whole growth stage. The stages of peak were different according to different varieties. NEAUS4 had the lowest peak and while SIDAN 19 had the highest among all stages. Ratio of chlorophyll a to b was low at seedling stage, reached the peak atjointing stage and then declined. SIDAN 19 had the lower level at the last stages.
文摘The results indicate that high protoplast quality corresponds to high stress tolerance. The damage of cell membrane is one of the important mechanisms of stress. The protective enzyme system(superoxide dismutase.peroxidase and catalase) plays an important role in stress tolerance. In the research of hormone it is suggested that ABA can induce chilling torlerance, and the mechanism may correlate with the special gene expression.
文摘The appropriate density of the hybrids with different plant morphotypes and grainyield of main maize hybrids in Henan province under different conditions and in different placeshave been studied for many years.The results indicalte that all the light intensity in middle andlow part of the plant,the single leaf weight(SLW) and the photosynthetic intensity decrease re-markably with the increase of plant density and leaf area index(LAI),and that all the charactersof the sirgle plant yield becorne inferior with different magnitudes.But the seriousness is slighterfor compact type hybrids than that for spread ones.Under high yield condition,the desirabledensity is 4250 to 5000 plants per mu(666. 67m^2)for compact maize hybrids and 3300 to 3500plants for spread ones.The yield differences between the two kinds of hybrid vary with the yieldlevels.
文摘Soil erosion induced by inappropriate tillage remains a serious problem on many agricultural fields in the humid tropics. Studies were conducted between 2004 and 2006, on an Alfisol in Ogbomoso in the Southern Guinea Savanna of Nigeria to evaluate the effectiveness of Vetiver Grass(Vetiveria nigritana) Strips(VGS) under different tillage systems. The experiment was split-plot laid out in a randomized complete block design with two replications on 6% slope with 18 runoff plots. Main plot treatments were tillage systems; Manual Clearing(MC), Ploughing(P) and Ploughing plus Harrowing(PH). Subplot treatments were VGS spaced at intervals of 5 m(eight strips) and 10 m(four strips) with the control(no-vetiver). Runoffs and soil losses were collected after each major storm. Chemical analyses of eroded sediments and runoff were determined. Data were analyzed using ANOVA at p<0.05. The results showed that tillage had no significant reduction in runoffs and soil losses, but they were reduced with MC compared with P and PH. Mean total runoff on 5 and 10 m VGS plots were significantly(p<0.05) lower than that of the control by 74.4% and 45.0%, respectively. Corresponding soils loss on 5 and 10 m VGS plots were 27.1% and 53.5%, respectively. Mean NO3-N levels in runoff water were lower under PH plots than those under MC plots by 79.0% and 66.5%, respectively in 2004 and 2006 growing seasons. VGS spaced at 5 m significantly(p<0.05) reduced NO3-N loss than the control by 108.8% in 2004. Nutrients loads of eroded sediments were consistently higher for the control(no-vetiver) plots and least for 5 m VGS plot. Carbon, nitrogen and phosphorus contents of eroded sediments were 90%-92.4%, 83%-83.6% and 97%-97.8%, respectively, and were lower on 5 m than other treatments. Maize grain yield was significantly(p<0.05) affected by both tillage and VGS spacing only in 2005 growing season. P plot produced higher grain yield than MC and PH by 79.9% and 99.1%, respectively. Also, grain yield on VGS plot was significantly(p<0.05) higher on 5 and 10 m VGS plots than the control by 82.2% and 85.4%, respectively. The significant beneficial effect of PH in producing higher yields was dwarfed by the potential danger of soil erosion in the absence of a soil erosion control measure. The results showed that a balance needed to be struck between mechanical clearance and protective measure against soil erosion.
基金Supported by Northeast Agricultural U niversity Young Science Found
文摘The two maize varieties,Yuanzheng 808(astrictive type) and Sidan 19(explanate type),were cultured in pots.There were six treatments which the proportion of NO 3 - N and NH 4 + N were 1∶0 (treatment 1),2∶1(treatment 2),1∶1(treatment 3),1∶2(treatment 4),0∶1(treatment 5) and CK(no nitrogen) respectively.After emergence of seedings,the samples were picked up per 20 days in the growth period and measured chlorophyll contents,nitrate reductase(NR) activity,the weight of dry matter and single plant seed yield respectively.The result showed that enhanced ammonium nutrition (EAN) may increase chlorophyll content,dry matter weight and single plant seed yield.But there was a difference between varieties.To Yuanzheng 808,treatment 2 was the highest yield in all treatments;but treatment 4 was the highest yield to Sidan 19.
基金Supported by Construction Found of Key Laboratory for Water-saving Agriculture in Universities of Heilongjiang Province (2006BAD29B01)National Science and Technology Program of China (2007BAD88B01)
文摘Aiming at less and un-uniform distribution rainfall problems, the serious draught in spring, low crop production and water efficiency in sandy soil area of Heilongjiang Province, the experiment of alternative furrow irrigation was conducted in Dumeng County in 2009. The purpose of the experiment was to find the water consumption law and its influence on maize yield. The results showed that the highest water consumption was during the heading stage and the highest daily consumption of water was during the filling stage. The stimulation effect of alternative furrow irrigation on yield was obvious in the appropriate irrigation level. The best irrigation pattern for the highest yield was as follows： the seedling stage was 325 m3. hm^-2; the jointing stage was 400 m3-hm^-2; and the filling stage was 288 m3- hm-2. The water consumption during each growing period was that the seedling was 38.85 mm; the jointing was 108.11 mm; the heading was 124.39 ram; the filling was 88.96 ram; the milk was 60.21 ram; and the harvesting was 47.89 mm.
文摘Southern corn rust(SCR) caused by Puccinia polysora Underw and maize stalk rot caused by Pythium inflatum Matthews(MSR-2) are two destructive diseases of maize(Zea mays L.) in China.Our previous studies indicated that maize inbred line Qi319 is highly resistant to SCR but susceptible to MSR-2,while inbred line 1145 is highly resistant to MSR-2 but susceptible to SCR.The SCR resistant gene(RppQ) in Qi319 and MSR-2 resistant gene(Rpi1) in 1145 have been mapped on chromosome 10 and 4 respectively.In this research,through marker-assisted selection(MAS) with the molecular markers,bnlg1937 tightly linked to Rpi1 and phi041 tightly linked to RppQ,pyramid breeding of the two kinds of disease resistant genes were carried out from the year of 2003 to 2007.Two homozygotic inbred lines of F5 generation,DR94-1-1-1 and DR36-1-1-1 were identified.MAS result suggested DR94-1-1-1 and DR36-1-1-1 contained the two resistance genes RppQ and Rpi1.Field inoculation tests confirmed their high resistance to the two diseases.In addition,field investigation indicated that the two selected inbred lines,particularly DR94-1-1-1,had excellent agronomic traits such as plant height,ear height and yield-relating traits including ear length,ear diameter,ear weight,kernels per ear,kernels per row and kernel weight per ear.The two selected inbred lines DR94-1-1-1 and DR36-1-1-1 can either be directly developed into commercial variety or used as immediate donors of SCR and MSR resistance breeding programs in maize.
基金Scientific Research Project of Chongqing Educational Commission (KJ051301)
文摘A pot culture trial was conducted to investigate the changes of the biomass and acid phosphatase （APase） activity in 10 maize lines under low-P stress. P-deficiency significantly decreased the biomass, but induced the significant enhancement of the APase activity. Since P-deficiency had smaller effects on the low-P tolerant maize lines compared with P-sensitive lines, it was demonstrated that differences of tolerance to P-deficiency existed among 10 different maize lines. In addition, the relative biomass and APase activity changed during the vegetative stage of development, and there existed a significant correlation between the biomass and APase activity under low-P stress. These results suggest that the biomass and APase activity can be regarded as indicative traits of maize lines for tolerance to low-P stress at seedling stage.
