In this study,in order to analyze the multiple factors affecting grain production in Sichuan Province,grain production data and its related variables from 1982 to 2022 were selected as the object of the study and empi...In this study,in order to analyze the multiple factors affecting grain production in Sichuan Province,grain production data and its related variables from 1982 to 2022 were selected as the object of the study and empirical research was conducted.The unit root test and cointegration test were applied to ensure the smoothness of the data,heteroskedasticity and autocorrelation tests were performed,and the model was adjusted to finally select a feasible generalized least squares model.The results show that all the examined influencing factors have a significant impact on grain yield in Sichuan Province,especially the sown area of grain crops,which has the most significant effect.Based on these findings,this study proposes the following recommendations:ensure sufficient sown area and high-quality arable land resources,accelerate the process of agricultural mechanization and intelligence,and use chemical fertilizers rationally,in order to enhance the grain production capacity of Sichuan Province and guarantee food security.展开更多
Decision Support Tool(DST)enables farmers to make site-specific crop management decisions;however,comprehensive calibration can be both costly and time-consuming.This study assessed the production and economic benefit...Decision Support Tool(DST)enables farmers to make site-specific crop management decisions;however,comprehensive calibration can be both costly and time-consuming.This study assessed the production and economic benefits of two calibrations of the Nutrient Expert(NE)tool for rice in Sri Lanka’s Alfisols:the basic calibration(Nutrient Expert Sri Lanka 1,NESL1)and the comprehensive calibration(Nutrient Expert Sri Lanka 2,NESL2).NESL1 was developed by adapting the South Indian version of NE to local conditions,while NESL2 was an updated version,using three years of data from 71 farmer fields.展开更多
[Objective] This paper aimed to understand the area change and distribu- tion of medium-low yield farmland, and offered basis to the improvement of mediumlow farmland and its increase of grain production in Tianjin. [...[Objective] This paper aimed to understand the area change and distribu- tion of medium-low yield farmland, and offered basis to the improvement of mediumlow farmland and its increase of grain production in Tianjin. [Method] Based on the statistical date of Tianjin and its relevant counties and districts, the yield standard was set up to classify high-yield, medium-yield and low-yield farmland in Tianjin. The author analyzed area change of medium-low yield farmland in six agricultural counties and districts （including Jixian County, Wuqing District, Baodi District, Ninghe County, Jinghai County and Dagang district of Binghai New Area） from 1980 to 2010. [Result] The results showed that the average yield of grain rose from 2 445 kg/hm^2 in 1980 to 5 130 kg/hm^2 in 2010, increasing 109.82%. The area of mediumlow yield farmland was reduced from 291 250.13 hm^2 in 1985 to 76 489.87 hm^2 in 2010, coming down 74%. In Tianjin, the area of medium-low yield farmland of 2010 accounted for 19% of the total farmland, of which the ratios of medium-low yield farmland of Jinghai County, Jixian County, Dagang district of Binghai New Area, Wuqing District, Baodi District and Ninghe County were 43.12%, 18.59%, 17.23%, 14.01%, 7.05% and 0, respectively. Low soil nutrient content, drought and water shortage, as well as soil salinization were the main yield limiting factors to mediumlow yield farmland in Tianjin in 2010. [Conclusion] The countermeasures to improve the medium-low yield farmland were proposed, involving enhancing the investment of the government, strengthening the construction of water conservancy infrastructure, further improving the soil fertility, as well as saline and alkaline land, optimizing the farming system and planting drought and salt tolerance crops, etc.展开更多
[Objective] This study aimed to analyze the influence of six cultivation fac- tors： sowing date, plant density, nitrogen fertilizer amount, phosphate fertilizer amount, potash fertilizer amount and boron fertilizer a...[Objective] This study aimed to analyze the influence of six cultivation fac- tors： sowing date, plant density, nitrogen fertilizer amount, phosphate fertilizer amount, potash fertilizer amount and boron fertilizer amount on seed oil yield of Brassica napus. [Method] Statistical analysis was carried out based on the data from previous studies and our work. [Result] Oil yield shared a negative correlation with sowing date, a parabolic relationship with plant density mostly, parabolic rela- tionships with amount of applied nitrogen fertilizer and amount of applied boron fer- tilizer, straight-line relationships with amount of applied phosphate fertilizer and amount of applied potash fertilizer. The average amount of applied nitrogen fertilizer required to obtain the highest oil yield was 185.18 kg/hm2 for high-oil rape varieties （with oil content above 44.00%）, and under this condition, the average oil yield of low-oil rape varieties （with oil content below 42.00%） was 1 247.84 kg/hm2, while that of high-oil rape varieties was 1 442.60 kg/hm2, which was 15.61% more than the former. The average amount of applied nitrogen fertilizer required to obtain the highest oil yield for lower-oil rape varieties was 286.28 kg/hm2, and under this con- dition, the average oil yield of the low-oil rape varieties was 1 350.57 kg/hm2, while that of the high-oil varieties was 6.81% higher than it. There was a significant neg- ative correlation between rapeseed oil yield and the amount of applied nitrogen fer- tilizer to obtain the highest oil yield （0.980 0）. The optimum amount of applied ni- trogen, phosphate, potash and boron fertilizer were 187.5-195, 187.5-195, 105-120, 135-150 and 15-22.5 kg/hm2 for high-oil B. napus varieties. [Conclusion] This study determined the influence of sowing date, plant density and amount of applied nitro- gen fertilizer on oil yield of B. napus, and proposed an optimum cultivation pattern for high-oil varieties.展开更多
[Objective] The aim was to research relationship of meteorological factors with rapeseed yield and yield components. [Method] A field test was carried out, with meteorological information collected from local Meteorol...[Objective] The aim was to research relationship of meteorological factors with rapeseed yield and yield components. [Method] A field test was carried out, with meteorological information collected from local Meteorological Administration. The data were then through statistical work and regression analysis was made on correlation of meteorological factors with yield and yield components supported by DPS. [Result] The number of pod per plant is closely related to meteorological fac- tors in seedling stage. Specifically, the number is of positive correlation with precipi- tation in seedling stage and of negative correlation with average temperature and sunshine hour. The number of grain per pod is of positive correlation with precipita- tion in seedling stage and negative correlation with temperature in seedling stage and sunshine hour in anthesis. Thousand-seed weight is of positive correlation with sunshine hour in seedling stage and negative correlation with precipitation in seedling stage. [Conclusion] Moisture of soils should be guaranteed by surface cov- erage in order to promote seedling growth, maintain ventilation in fields and reduce effects of rainfall on rapeseed flowering.展开更多
North China Plain(NCP) is the primary winter wheat production region in China, characterized by smallholder farming systems. Whereas the winter wheat average yield of smallholder farmers is currently low, the yield po...North China Plain(NCP) is the primary winter wheat production region in China, characterized by smallholder farming systems. Whereas the winter wheat average yield of smallholder farmers is currently low, the yield potential and limiting factors driving the current yield gap remain unclear. Therefore, increasing the wheat yield in NCP is essential for the national food security. This study monitored wheat yield, management practices and soil nutrient data in 132 farmers’ fields of Xushui County, Baoding City, Hebei Province during 2014–2016. These data were analyzed using variance and path analysis to determine the yield gap and the contribution of yield components(i.e., spikes per hectare, grain number per spike and 1 000-grain weight) to wheat yield. Then, the limiting factors of yield components and the optimizing strategies were identified by a boundary line approach. The results showed that the attainable potential yield for winter wheat was 10 514 kg ha^–1. The yield gaps varied strongly between three yield groups(i.e., high, middle and low), which were divided by yield level and contained 44 farmers in each group, and amounted to 2 493, 1 636 and 814 kg ha^–1, respectively. For the three yield components, only spikes per hectare was significantly different(P<0.01) among the three yield groups. For all 132 farmers’ fields, correlation between yield and spikes per hectare(r=0.51, P<0.01), was significantly positive, while correlations with grain number per spike(r=–0.16) and 1 000-grain weight(r=–0.10) were not significant. The path analysis also showed that the spikes per hectare of winter wheat were the most important component to the wheat yield. Boundary line analysis showed that seeding date was the most limiting factor of spikes per hectare with the highest contribution rate(26.7%), followed by basal N input(22.1%) and seeding rate(14.5%), which indicated that management factors in the seeding step were the most important for affecting spikes per hectare. For desired spikes per hectare(>6.598×10^6 ha^–1),the seeding rate should range from 210–300 kg ha^–1, seeding date should range from 3th to 8th October, and basal N input should range from 90–180 kg ha^–1. Compared to these reasonable ranges of management measures, most of the farmers’ practices were not suitable, and both lower and higher levels of management existed. It is concluded that the strategies for optimizing yield components could be achieved by improving wheat seeding quality and optimizing farmers’ nutrient management practices in the NCP.展开更多
The mechanism of action of ecological factors affecting crop growth and development was complicated. In order to study the relationships between ecological factors and the indexes of yield property equation and determ...The mechanism of action of ecological factors affecting crop growth and development was complicated. In order to study the relationships between ecological factors and the indexes of yield property equation and determine the main ecological factors affecting yield, using 3-yr field experimental results for different yielding spring maize （Zea mays L.） populations and the relative meteorological observation data in Huadian of Jilin Province in China, and analyzing on the base of the yield property equation （MLAI × D × MNAR × HI = EN × GN × GW）, the main ecological factors were screened, and further mechanisms of action affecting yield were analyzed. Stepwise regression analysis showed that yield was affected mainly by effective accumulated temperature, daily mean minimum temperature, daily mean maximum temperature in July, the ratios of growth days, and the sunshine hour before and after silking. In yield property equation, four indexes of MLAI, growth days, ear number and grain number （total grain number） affected principally yield, the ecological factors affecting predominantly yield were effective accumulated temperature, daily mean temperature, daily mean minimum temperature, daily mean maximum temperature in July, the ratios of growth days, rainfall, accumulated temperature, and sunshine hours before and after silking. Combined with the two analytical methods, it could be deduced that the temperature and the allocated ratios before and after silking of ecological factors were the key factors to achieve high yield. Therefore, appropriate sowing data should be adjusted to achieve the suitable temperature indexes during the whole growth stage and the rational allocated ratios of ecological factors before and after silking.展开更多
In recent years, the role of human activities in changing sediment yield has become more apparent for the construction of hydraulic engineering and water conservation projections in the Upper Yangtze River, but it has...In recent years, the role of human activities in changing sediment yield has become more apparent for the construction of hydraulic engineering and water conservation projections in the Upper Yangtze River, but it has not been evaluated at the macro scale. Taking Sichuan Province and Chongqing City as an example, this paper studies the relationship between socio-economic factors and sediment yield in the Upper Yangtze River based on section data in 1989 and 2007. The results show that sediment yield is significantly correlated with population density and cultivated area, in which the former appears to be more closely related to sediment yield. Moreover, in the relation of sediment yield vs. population density, a critical value of population density exists, below which the sediment yield increases with the increase of population density and over which the sediment yield increases with the decrease of population density. The phenomenon essentially reflects the influence of natural factors, such as topography, precipitation and soil property, and some human activities on sediment yield. The region with a higher population density than critical value is located in the east of the study area and is characterized by plains, hills and low mountains, whereas the opposite is located in the west and characterized by middle and high mountains. In the eastern region, more people live on the lands with a low slope where regional soil erosion is slight; therefore, sediment yield is negatively related with population density. In contrast, in the western region, the population tends to aggregate in the areas with abundant soil and water resources which usually lead to a higher intensity of natural erosion, and in turn, high-intensity agricultural practices in these areas may further strengthen local soil erosion. It is also found that population tends to move from the areas with bad environment and high sediment yield to the areas with more comfortable environment and less sediment yield. The natural factors have greater influence on sediment yield of western region than that of eastern region. Generally, the natural factors play a dominant role on sediment yield in the Upper Yangtze River.展开更多
A systematic approach was adopted to investigate the nutrient limiting factors in gray-brown purple soils and yellow soils derived from limestone in Chongqing, China, to study balanced fertilization for corn, sweet po...A systematic approach was adopted to investigate the nutrient limiting factors in gray-brown purple soils and yellow soils derived from limestone in Chongqing, China, to study balanced fertilization for corn, sweet potato and wheat in rotation. The results showed that N, P and K were deficient in both soils, Cu, Mn, S andZn in the gray-brown purple soils and Ca, Mg, Mo and Zn for the yellow soils. Balanced fertilizer application increased yields of corn, sweet potato and wheat by 28.4%, 28.7% and 4.4%, respectively, as compared to the local farmers' practice. The systematic approach can be considered as one of the most efficient and reliable methods in fertility study.展开更多
In order to investigate the effect of meteorological factors on the yield and quality of special rice during the filling stage, an experiment was conducted with 10 special rice varieties which were planted in three di...In order to investigate the effect of meteorological factors on the yield and quality of special rice during the filling stage, an experiment was conducted with 10 special rice varieties which were planted in three different regions during spring 2017. The results showed that the quality traits and yields from different regions of the same variety were different, which reached up to a significant level in most varieties. Among the quality traits, the grain chalkiness rate and chalkiness degree were the most sensitive to different climatic factors, and changes were found among them in different regions, while minor variation was found between brown rice rate and white rice rate. The parameters that were severely affected by temperature were gel consistency, gelatinization temperature, brown rice rate and yield during the filling stage. The critically affected factors by heat were brown rice rate, protein content, essential amino acid and amylose content while brown rice rate, chalkiness rate and gelatinization temperature were substantially affected by water factors. Grain yield and quality were closely related to meteorological factors on different stages after heading. Our results revealed that yield and quality of special rice were significantly influenced by meteorological factors during the grain filling stage.展开更多
The changes of meteorological factors such as average temperature, pre- cipitation and sunshine duration in the whole growth period and at various growth stages of spring peanut in Dengzhou City during 2001-2016 were ...The changes of meteorological factors such as average temperature, pre- cipitation and sunshine duration in the whole growth period and at various growth stages of spring peanut in Dengzhou City during 2001-2016 were analyzed, and their effects on the growth and development of spring peanut were discussed. The results show that from 2001 to 2016, average temperature tended to increase in the growth period of spring peanut in Dengzhou City, but the increasing trend was slow; precipitation showed a decreasing trend on the whole （it increased at the sowing and flowering stage）; sunshine duration reduced year by year （the decreasing trend was different at various growth stages）, but the decrease of sunshine duration was more obvious than that of precipitation. Based on the analysis of meteorological conditions and the growth rules of spring peanut, it is needed to scientifically choose varieties of spring peanut, plan suitable sowing patterns, apply and manage- fertilizer and water to reasonably realize sustainable high-yield of spring peanut based on its safe stable yield.展开更多
Understanding yield potential, yield gap and the priority of management factors for reducing the yield gap in current intensive maize production is essential for meeting future food demand with the limited resources. ...Understanding yield potential, yield gap and the priority of management factors for reducing the yield gap in current intensive maize production is essential for meeting future food demand with the limited resources. In this study, we conducted field experiments using different planting modes, which were basic productivity(CK), farmer practice(FP), high yield and high efficiency(HH), and super high yield(SH), to estimate the yield gap. Different factorial experiments(fertilizer, planting density, hybrids, and irrigation) were also conducted to evaluate the priority of individual management factors for reducing the yield gap between the different planting modes. We found significant differences between the maize yields of different planting modes. The treatments of CK, FP, HH, and SH achieved 54.26, 58.76, 65.77, and 71.99% of the yield potential, respectively. The yield gaps between three pairs: CK and FP, FP and HH, and HH and SH, were 0.76, 1.23 and 0.85 t ha^(–1), respectively. By further analyzing the priority of management factors for reducing the yield gap between FP and HH, as well as HH and SH, we found that the priorities of the management factors(contribution rates) were plant density(13.29%)>fertilizer(11.95%)>hybrids(8.19%)>irrigation(4%) for FP to HH, and hybrids(8.94%)>plant density(4.84%)>fertilizer(1.91%) for HH to SH. Therefore, increasing the planting density of FP was the key factor for decreasing the yield gap between FP and HH, while choosing hybrids with density and lodging tolerance was the key factor for decreasing the yield gap between HH and SH.展开更多
Abiotic stresses like salinity and drought directly affect plant growth and water availability, resulting in lower yield in rice. So, a combination of stress tolerance along with enhanced grain yield is a major focus ...Abiotic stresses like salinity and drought directly affect plant growth and water availability, resulting in lower yield in rice. So, a combination of stress tolerance along with enhanced grain yield is a major focus of rice breeding. It was reported earlier that loss in function of the drought and salt tolerance (DST) gene results in increase in grain production through downregulating Gn1a/OsCKX2 expression. Moreover, dst mutants also showed enhanced drought and salt tolerance in rice by regulating genes involved in ROS homeostasis. In the present study, we proceeded to test these reports by downregulating DST using artificial microRNA technology in the commercial but salt sensitive, high-yielding, BRRIdhan 28 (BR28). This cultivar was transformed with DST_artificial microRNA (DST_amiRNA) driven by the constitutive CaMV35S promoter using tissue culture independent Agrobacterium mediated in planta transformation. DST_amiRNA transgenic plants were confirmed by artificial microRNA specific PCR. Transformed plants at T0 generation showed vigorous growth with significantly longer panicle length and higher primary branching resulting in higher yield, compared to the wild type (WT) BR28. Semi-quantitative RT PCR confirmed the decrease in DST expression in the BR28 transgenic plants compared to WT. T1 transgenic plants also showed improvement in a number of physiological parameters and greater growth compared to WT after 14 days of 120 mM salt (NaCl) stress at seedling stage. Therefore, DST downregulated transgenic plants showed both higher stress tolerance as well as better yields. Furthermore, stable inheritance of the improved phenotype of the DST_amiRNA transgenics will be tested in advanced generations.展开更多
The aim was to research effects of meteorological factors on yield of ryegrass in fal ow field in winter. [Method] With grass yield as a dependent variable, effects of meteorological factors on ryegrass yield were exp...The aim was to research effects of meteorological factors on yield of ryegrass in fal ow field in winter. [Method] With grass yield as a dependent variable, effects of meteorological factors on ryegrass yield were explored by differ-ent planting methods. [Result] The yield of Zuanshi T was higher than that of Tegao; strip sowing performed better compared with dispersedly sowing and plough-ing better than no-til age; extremely high and low temperatures showed negative correlation with grass yield; higher daily average temperature, rainfal and sunshine hour improved grass yield; relative humidity and frost-free period had insignificant effects on yield. [Conclusion] The region with less extreme temperatures should be chosen as the site for growing ryegrass.展开更多
There are numerous factors which can affect the lymph node(LN) yield in colon cancer specimens.The aim of this paper was to identify both modifiable and nonmodifiable factors that have been demonstrated toaffect colon...There are numerous factors which can affect the lymph node(LN) yield in colon cancer specimens.The aim of this paper was to identify both modifiable and nonmodifiable factors that have been demonstrated toaffect colonic resection specimen LN yield and to summarise the pertinent literature on these topics.A literature review of Pub Med was performed to identify the potential factors which may influence the LN yield in colon cancer resection specimens.The terms used for the search were:LN,lymphadenectomy,LN yield,LN harvest,LN number,colon cancer and colorectal cancer.Both nonmodifiable and modifiable factors were identified.The review identified fifteen non-surgical factors:(13 nonmodifiable,2 modifiable) which may influence LN yield.LN yield is frequently reduced in older,obese patients and those with male sex and increased in patients with right sided,large,and poorly differentiated tumours.Patient ethnicity and lower socioeconomic class may negatively influence LN yield.Pre-operative tumour tattooing appears to increase LN yield.There are many factors that potentially influence the LN yield,although the strength of the association between the two varies greatly.Perfecting oncological resection and pathological analysis remain the cornerstones to achieving good quality and quantity LN yields in patients with colon cancer.展开更多
Climate change is one of the most important challenges threatening agricultural grain yield and food security. Determining the factors influencing grain yield in Jilin Province and the weights of their contribution ar...Climate change is one of the most important challenges threatening agricultural grain yield and food security. Determining the factors influencing grain yield in Jilin Province and the weights of their contribution are a very important task, because Jilin Province is an important agriculture base in China. In this study, the accumulation factor sequence evaluating data method was used to analyze the climate and economic-technical factor contribution weights to grain yield and grain yield changes in each city of Jilin Province. Climate yield was also estimated to study the climate effect on the grain yield, and it was calculated in two ways： an improved algorithm and a traditional quadratic method. The results show that the climate and economicechnical factors have different contribution weights to grain yield in different cities in Jilin Province. The contribution weight of the climate factor to grain yield was 0.212-0.349, while that the economic-technical factor was 0.651-0.788. Furthermore, the changes of the climate factor contributing to grain yield changes accounted for 0.296-0.546, and the changes of the economic-technical factor accounted for 0.454-0.704. The weights of climate and economic-technical factor contributing to grain yield are very different between the eastern and western cities in Jilin Province, but their weights contributing to the grain yield change are similar in these cities. In general, the amount of fertilizer used per hectare （FUPH） is the main factor affecting grain yields and yield changes from 1980 to 2008. It is noted that when the FUPH growth rate stabilized after 1995, the effects of the climate factor on the grain yield become more obvious than before. The improved algorithm is effective for esti- mating climate yield in Jilin Province, and the climate yields were mostly between -500 kg/ha and 500 kg/ha, and showed a slightly rising trend in most cities.展开更多
Effects of environmental factors such as climate,topography,vegetation and soil in shelter forests in Three Gorges Reservoir Region on runoff and sediment yields were monitored to identify dominant environmental facto...Effects of environmental factors such as climate,topography,vegetation and soil in shelter forests in Three Gorges Reservoir Region on runoff and sediment yields were monitored to identify dominant environmental factors controlling runoff and sediment yields in 15 runoff plots in study area by soil sampling,laboratory analysis,stepwise regression analysis and path analysis,and to establish the main control environmental factors that affect runoff and sediment yields. The results showed that soil bulk density,herbaceous cover,slope,and canopy density were the significant factors controlling runoff,and the direct path coefficient of each factor was ranked as canopy closure(-0. 628) > litter thickness(-0. 547) > bulk density( 0. 509) > altitude( 0. 289). The indirect path coefficient was ranked as soil bulk density( 0. 354) >litter thickness(-0. 169) > altitude( 0. 126) > canopy closure(-0. 104). Therefore,canopy closure and litter thickness mainly had direct effects on runoff,while soil bulk density mainly had indirect effects through their contributions to other factors. Herbaceous cover,litter thickness,slope,canopy density,and altitude were the significant factors controlling sediment yields. The direct path coefficient of each factor was ranked as herbaceous cover(-0. 815) > litter thickness(-0. 777) > canopy closure(-0. 624) > slope( 0. 620). The indirect path coefficient was ranked as slope( 0. 272) > litter thickness(-0. 131) > canopy closure(-0. 097) > herbaceous cover(-0. 084). Therefore,herbaceous cover and litter thickness mainly had direct effects on sediment yields,while slope mainly had indirect effects through their contributions to other factors. All the selected environmental factors jointly explained 85. 5% and 78. 3% of runoff and sediment yield variability,respectively. However,there were large values of remaining path coefficients of other factors influencing runoff and sediment yields,which indicated that some important factors are not included and should be taken into account.展开更多
The experiment was did in Liaocheng of west Shandong Province from^2009 to 2013 with ‘Lumianyan 28＇ which widely popularized and applied in production as test materials. The author discussed the influence of meteoro...The experiment was did in Liaocheng of west Shandong Province from^2009 to 2013 with ‘Lumianyan 28＇ which widely popularized and applied in production as test materials. The author discussed the influence of meteorological factors change on cotton yield characteristic in different years. The results were as follow：firstly, the accumulated temperature change was not significant in growth period, the coefficient of variation of sunshine hour was up to 7.4%, the coefficient of variation of precipitation was up to 18.4%; secondly, sunshine hour and, seed cotton yield,seed cotton yield before frost, lint yield were positively correlated; last, precipitation and seed cotton yield, seed cotton yield before frost, lint yield were negatively correlated, all reached significant level. It was showed that precipitation was the key meteorological conditions affecting cotton production.展开更多
In order to investigate the effects of meteorological factors on rape overwintering ability,forage yield and quality of rape in the North China plain,Brassia campestris L.and Brassica napus L.were used in this study.T...In order to investigate the effects of meteorological factors on rape overwintering ability,forage yield and quality of rape in the North China plain,Brassia campestris L.and Brassica napus L.were used in this study.The results showed that compared with the B.napus L.varieties,the growth period of B.campestris L.was shortened by 10-15 d,the overwintering rate(WR)increased by 50.6%,and the density after winter(PD)increased by 41.5%.The fresh forage yield(FFY)and dry forage yield(DFY)of the B.campestris L.type significantly increased by 40.9%and 38.1%compared with the B.napus L.type.,respectively,while the forage quality of the B.napus L.type rape was significantly better than that of the B.campestris L.type.Compared with the B.campestris L.type,the crude protein(CP),fat,ash and total fatty acid(TFA)contents of the B.napus L.type of rape increased by 27.6%,42.9%,23.9%and 52.3%,respectively,and the milk productivity(HM),relative forage value(RFV)and relative forage quality(RFQ)increased by 14.0%,16.2%and 42.1%,respectively.The light and heat resources before wintering increased the WR and PD(P<0.05),and were positively correlated with FFY and DFY(P>0.05),and lower temperature during the wintering period led to lower WR(P<0.01).The light and heat resources during the overwintering period and after regreening were negatively correlated with FFY and DFY(P>0.05).The contents of CP,fat and TFA of rape had an extremely significant negative correlation with the temperature and sunshine hours before wintering,but an extremely significant positive correlation with the temperature during the wintering period and after regreening,as well as the sunshine hours and rainfall during the wintering period;and HM had an extremely significant positive correlation with the temperature,sunshine hours and rainfall during the wintering period,while RFV and RFQ were only extremely significantly positively correlated with the maximum temperature and rainfall.In summary,in the North China Plain,for autumn sowing rape,the B.campestris L.type can be selected to improve the wintering rate,and the B.napus L.type should be the main choice to improve the forage quality of rape.Therefore,the B.napus L.variety HYZ62 can be selected for autumn sowing in the North China Plain.展开更多
Middle-season rice is an important food crop in southern rice areas of China,especially in Yunnan,the main rice-producing region.However,due to the impact of low temperature at the seedling stage and high or low tempe...Middle-season rice is an important food crop in southern rice areas of China,especially in Yunnan,the main rice-producing region.However,due to the impact of low temperature at the seedling stage and high or low temperature at the booting and heading stage of middle-season rice,the yield is not stable.Based on the data of yield factors of different middle-season rice varieties planted in the same ecological site in Jingdong County from 2009 to 2016,average development period was calculated using the data of development period measured in field during 2009-2016,and the average of meteorological factors(daily average temperature,daily maximum temperature,daily minimum temperature,and sunshine hours)and total precipitation were calculated.The correlation between meteorological factors in different development periods of each year and corresponding per unit area yield was analyzed.The results show that temperature is the most important factor affecting rice yield.Sufficient light is beneficial to the increase in the number of grains per spike and thousand seed weight at the sowing-seedling emergence stage and milk maturity-maturity stage.Excessive precipitation will reduce the number of grains per spike at the booting-heading stage.Excessive precipitation decreases the number of filled grains per spike at the jointing-booting stage,and proper drainage helps increase the formation rate of ears.This study provides scientific reference for rice production and management in this county in future.展开更多
文摘In this study,in order to analyze the multiple factors affecting grain production in Sichuan Province,grain production data and its related variables from 1982 to 2022 were selected as the object of the study and empirical research was conducted.The unit root test and cointegration test were applied to ensure the smoothness of the data,heteroskedasticity and autocorrelation tests were performed,and the model was adjusted to finally select a feasible generalized least squares model.The results show that all the examined influencing factors have a significant impact on grain yield in Sichuan Province,especially the sown area of grain crops,which has the most significant effect.Based on these findings,this study proposes the following recommendations:ensure sufficient sown area and high-quality arable land resources,accelerate the process of agricultural mechanization and intelligence,and use chemical fertilizers rationally,in order to enhance the grain production capacity of Sichuan Province and guarantee food security.
基金supported by the National Research Council of Sri Lanka(Grant No.NRC TO 16-07).
文摘Decision Support Tool(DST)enables farmers to make site-specific crop management decisions;however,comprehensive calibration can be both costly and time-consuming.This study assessed the production and economic benefits of two calibrations of the Nutrient Expert(NE)tool for rice in Sri Lanka’s Alfisols:the basic calibration(Nutrient Expert Sri Lanka 1,NESL1)and the comprehensive calibration(Nutrient Expert Sri Lanka 2,NESL2).NESL1 was developed by adapting the South Indian version of NE to local conditions,while NESL2 was an updated version,using three years of data from 71 farmer fields.
文摘[Objective] This paper aimed to understand the area change and distribu- tion of medium-low yield farmland, and offered basis to the improvement of mediumlow farmland and its increase of grain production in Tianjin. [Method] Based on the statistical date of Tianjin and its relevant counties and districts, the yield standard was set up to classify high-yield, medium-yield and low-yield farmland in Tianjin. The author analyzed area change of medium-low yield farmland in six agricultural counties and districts （including Jixian County, Wuqing District, Baodi District, Ninghe County, Jinghai County and Dagang district of Binghai New Area） from 1980 to 2010. [Result] The results showed that the average yield of grain rose from 2 445 kg/hm^2 in 1980 to 5 130 kg/hm^2 in 2010, increasing 109.82%. The area of mediumlow yield farmland was reduced from 291 250.13 hm^2 in 1985 to 76 489.87 hm^2 in 2010, coming down 74%. In Tianjin, the area of medium-low yield farmland of 2010 accounted for 19% of the total farmland, of which the ratios of medium-low yield farmland of Jinghai County, Jixian County, Dagang district of Binghai New Area, Wuqing District, Baodi District and Ninghe County were 43.12%, 18.59%, 17.23%, 14.01%, 7.05% and 0, respectively. Low soil nutrient content, drought and water shortage, as well as soil salinization were the main yield limiting factors to mediumlow yield farmland in Tianjin in 2010. [Conclusion] The countermeasures to improve the medium-low yield farmland were proposed, involving enhancing the investment of the government, strengthening the construction of water conservancy infrastructure, further improving the soil fertility, as well as saline and alkaline land, optimizing the farming system and planting drought and salt tolerance crops, etc.
基金Supported by Earmarked Fund for Modern Rapeseed Research System of China(nycytx-00563)High-oil Hybrid Brassica napus Rapeseed Cultivation Technology Research Program of Guizhou Academy of Agricultural Sciences[ZX(2007)015]+3 种基金Hybrid Rapeseed Cultivar Yoyan 599 Promotion Program of Guizhou Academy of Agricultural Sciences[(2009)030]New High-yield Rapeseed Cultivar Yoyan 599 Cultivation and Promotion Program of Agriculture department of Guizhou Province[(2009)007]New High-oil Rapeseed Cultivar Sanbei 98 Cultivation and Promotion Program of Agriculture Department of Guizhou Province[(2010)3087]Earmarked Fund for Modern Rapeseed Research System of Guizhou Province(GZCYTX2013-0802)~~
文摘[Objective] This study aimed to analyze the influence of six cultivation fac- tors： sowing date, plant density, nitrogen fertilizer amount, phosphate fertilizer amount, potash fertilizer amount and boron fertilizer amount on seed oil yield of Brassica napus. [Method] Statistical analysis was carried out based on the data from previous studies and our work. [Result] Oil yield shared a negative correlation with sowing date, a parabolic relationship with plant density mostly, parabolic rela- tionships with amount of applied nitrogen fertilizer and amount of applied boron fer- tilizer, straight-line relationships with amount of applied phosphate fertilizer and amount of applied potash fertilizer. The average amount of applied nitrogen fertilizer required to obtain the highest oil yield was 185.18 kg/hm2 for high-oil rape varieties （with oil content above 44.00%）, and under this condition, the average oil yield of low-oil rape varieties （with oil content below 42.00%） was 1 247.84 kg/hm2, while that of high-oil rape varieties was 1 442.60 kg/hm2, which was 15.61% more than the former. The average amount of applied nitrogen fertilizer required to obtain the highest oil yield for lower-oil rape varieties was 286.28 kg/hm2, and under this con- dition, the average oil yield of the low-oil rape varieties was 1 350.57 kg/hm2, while that of the high-oil varieties was 6.81% higher than it. There was a significant neg- ative correlation between rapeseed oil yield and the amount of applied nitrogen fer- tilizer to obtain the highest oil yield （0.980 0）. The optimum amount of applied ni- trogen, phosphate, potash and boron fertilizer were 187.5-195, 187.5-195, 105-120, 135-150 and 15-22.5 kg/hm2 for high-oil B. napus varieties. [Conclusion] This study determined the influence of sowing date, plant density and amount of applied nitro- gen fertilizer on oil yield of B. napus, and proposed an optimum cultivation pattern for high-oil varieties.
基金Supported by National Natural Science Foundation of China(31360346)Yunnan Modern Agricultural Rapeseed-industry Technology System~~
文摘[Objective] The aim was to research relationship of meteorological factors with rapeseed yield and yield components. [Method] A field test was carried out, with meteorological information collected from local Meteorological Administration. The data were then through statistical work and regression analysis was made on correlation of meteorological factors with yield and yield components supported by DPS. [Result] The number of pod per plant is closely related to meteorological fac- tors in seedling stage. Specifically, the number is of positive correlation with precipi- tation in seedling stage and of negative correlation with average temperature and sunshine hour. The number of grain per pod is of positive correlation with precipita- tion in seedling stage and negative correlation with temperature in seedling stage and sunshine hour in anthesis. Thousand-seed weight is of positive correlation with sunshine hour in seedling stage and negative correlation with precipitation in seedling stage. [Conclusion] Moisture of soils should be guaranteed by surface cov- erage in order to promote seedling growth, maintain ventilation in fields and reduce effects of rainfall on rapeseed flowering.
基金supported by the National Basic Research Program of China (2015CB150405)the Special Fund for Agro-scientific Research in the Public Interest, China (201103003)
文摘North China Plain(NCP) is the primary winter wheat production region in China, characterized by smallholder farming systems. Whereas the winter wheat average yield of smallholder farmers is currently low, the yield potential and limiting factors driving the current yield gap remain unclear. Therefore, increasing the wheat yield in NCP is essential for the national food security. This study monitored wheat yield, management practices and soil nutrient data in 132 farmers’ fields of Xushui County, Baoding City, Hebei Province during 2014–2016. These data were analyzed using variance and path analysis to determine the yield gap and the contribution of yield components(i.e., spikes per hectare, grain number per spike and 1 000-grain weight) to wheat yield. Then, the limiting factors of yield components and the optimizing strategies were identified by a boundary line approach. The results showed that the attainable potential yield for winter wheat was 10 514 kg ha^–1. The yield gaps varied strongly between three yield groups(i.e., high, middle and low), which were divided by yield level and contained 44 farmers in each group, and amounted to 2 493, 1 636 and 814 kg ha^–1, respectively. For the three yield components, only spikes per hectare was significantly different(P<0.01) among the three yield groups. For all 132 farmers’ fields, correlation between yield and spikes per hectare(r=0.51, P<0.01), was significantly positive, while correlations with grain number per spike(r=–0.16) and 1 000-grain weight(r=–0.10) were not significant. The path analysis also showed that the spikes per hectare of winter wheat were the most important component to the wheat yield. Boundary line analysis showed that seeding date was the most limiting factor of spikes per hectare with the highest contribution rate(26.7%), followed by basal N input(22.1%) and seeding rate(14.5%), which indicated that management factors in the seeding step were the most important for affecting spikes per hectare. For desired spikes per hectare(>6.598×10^6 ha^–1),the seeding rate should range from 210–300 kg ha^–1, seeding date should range from 3th to 8th October, and basal N input should range from 90–180 kg ha^–1. Compared to these reasonable ranges of management measures, most of the farmers’ practices were not suitable, and both lower and higher levels of management existed. It is concluded that the strategies for optimizing yield components could be achieved by improving wheat seeding quality and optimizing farmers’ nutrient management practices in the NCP.
基金supported by the National High-Tech Research and Development Program of China(2006AA10Z272)the National Basic Research Program of China (2006BAD02A13)
文摘The mechanism of action of ecological factors affecting crop growth and development was complicated. In order to study the relationships between ecological factors and the indexes of yield property equation and determine the main ecological factors affecting yield, using 3-yr field experimental results for different yielding spring maize （Zea mays L.） populations and the relative meteorological observation data in Huadian of Jilin Province in China, and analyzing on the base of the yield property equation （MLAI × D × MNAR × HI = EN × GN × GW）, the main ecological factors were screened, and further mechanisms of action affecting yield were analyzed. Stepwise regression analysis showed that yield was affected mainly by effective accumulated temperature, daily mean minimum temperature, daily mean maximum temperature in July, the ratios of growth days, and the sunshine hour before and after silking. In yield property equation, four indexes of MLAI, growth days, ear number and grain number （total grain number） affected principally yield, the ecological factors affecting predominantly yield were effective accumulated temperature, daily mean temperature, daily mean minimum temperature, daily mean maximum temperature in July, the ratios of growth days, rainfall, accumulated temperature, and sunshine hours before and after silking. Combined with the two analytical methods, it could be deduced that the temperature and the allocated ratios before and after silking of ecological factors were the key factors to achieve high yield. Therefore, appropriate sowing data should be adjusted to achieve the suitable temperature indexes during the whole growth stage and the rational allocated ratios of ecological factors before and after silking.
基金Commonweal Special Project of the Minislry of Water Resources of China, No.2007SHZ0901034 National Natural Science Foundation of China, No.40971012 Acknowledgements We are grateful to Data Center for Resources and Environmental Sciences of Chinese Academy of Sciences for providing the data of soil and to China Meteorological Administration for providing the data of precipitation.
文摘In recent years, the role of human activities in changing sediment yield has become more apparent for the construction of hydraulic engineering and water conservation projections in the Upper Yangtze River, but it has not been evaluated at the macro scale. Taking Sichuan Province and Chongqing City as an example, this paper studies the relationship between socio-economic factors and sediment yield in the Upper Yangtze River based on section data in 1989 and 2007. The results show that sediment yield is significantly correlated with population density and cultivated area, in which the former appears to be more closely related to sediment yield. Moreover, in the relation of sediment yield vs. population density, a critical value of population density exists, below which the sediment yield increases with the increase of population density and over which the sediment yield increases with the decrease of population density. The phenomenon essentially reflects the influence of natural factors, such as topography, precipitation and soil property, and some human activities on sediment yield. The region with a higher population density than critical value is located in the east of the study area and is characterized by plains, hills and low mountains, whereas the opposite is located in the west and characterized by middle and high mountains. In the eastern region, more people live on the lands with a low slope where regional soil erosion is slight; therefore, sediment yield is negatively related with population density. In contrast, in the western region, the population tends to aggregate in the areas with abundant soil and water resources which usually lead to a higher intensity of natural erosion, and in turn, high-intensity agricultural practices in these areas may further strengthen local soil erosion. It is also found that population tends to move from the areas with bad environment and high sediment yield to the areas with more comfortable environment and less sediment yield. The natural factors have greater influence on sediment yield of western region than that of eastern region. Generally, the natural factors play a dominant role on sediment yield in the Upper Yangtze River.
文摘A systematic approach was adopted to investigate the nutrient limiting factors in gray-brown purple soils and yellow soils derived from limestone in Chongqing, China, to study balanced fertilization for corn, sweet potato and wheat in rotation. The results showed that N, P and K were deficient in both soils, Cu, Mn, S andZn in the gray-brown purple soils and Ca, Mg, Mo and Zn for the yellow soils. Balanced fertilizer application increased yields of corn, sweet potato and wheat by 28.4%, 28.7% and 4.4%, respectively, as compared to the local farmers' practice. The systematic approach can be considered as one of the most efficient and reliable methods in fertility study.
文摘In order to investigate the effect of meteorological factors on the yield and quality of special rice during the filling stage, an experiment was conducted with 10 special rice varieties which were planted in three different regions during spring 2017. The results showed that the quality traits and yields from different regions of the same variety were different, which reached up to a significant level in most varieties. Among the quality traits, the grain chalkiness rate and chalkiness degree were the most sensitive to different climatic factors, and changes were found among them in different regions, while minor variation was found between brown rice rate and white rice rate. The parameters that were severely affected by temperature were gel consistency, gelatinization temperature, brown rice rate and yield during the filling stage. The critically affected factors by heat were brown rice rate, protein content, essential amino acid and amylose content while brown rice rate, chalkiness rate and gelatinization temperature were substantially affected by water factors. Grain yield and quality were closely related to meteorological factors on different stages after heading. Our results revealed that yield and quality of special rice were significantly influenced by meteorological factors during the grain filling stage.
文摘The changes of meteorological factors such as average temperature, pre- cipitation and sunshine duration in the whole growth period and at various growth stages of spring peanut in Dengzhou City during 2001-2016 were analyzed, and their effects on the growth and development of spring peanut were discussed. The results show that from 2001 to 2016, average temperature tended to increase in the growth period of spring peanut in Dengzhou City, but the increasing trend was slow; precipitation showed a decreasing trend on the whole （it increased at the sowing and flowering stage）; sunshine duration reduced year by year （the decreasing trend was different at various growth stages）, but the decrease of sunshine duration was more obvious than that of precipitation. Based on the analysis of meteorological conditions and the growth rules of spring peanut, it is needed to scientifically choose varieties of spring peanut, plan suitable sowing patterns, apply and manage- fertilizer and water to reasonably realize sustainable high-yield of spring peanut based on its safe stable yield.
基金the National Key Research and Development Program of China(2016YFD0300106)the National Natural Science Foundation of China(31601247)for their financial support。
文摘Understanding yield potential, yield gap and the priority of management factors for reducing the yield gap in current intensive maize production is essential for meeting future food demand with the limited resources. In this study, we conducted field experiments using different planting modes, which were basic productivity(CK), farmer practice(FP), high yield and high efficiency(HH), and super high yield(SH), to estimate the yield gap. Different factorial experiments(fertilizer, planting density, hybrids, and irrigation) were also conducted to evaluate the priority of individual management factors for reducing the yield gap between the different planting modes. We found significant differences between the maize yields of different planting modes. The treatments of CK, FP, HH, and SH achieved 54.26, 58.76, 65.77, and 71.99% of the yield potential, respectively. The yield gaps between three pairs: CK and FP, FP and HH, and HH and SH, were 0.76, 1.23 and 0.85 t ha^(–1), respectively. By further analyzing the priority of management factors for reducing the yield gap between FP and HH, as well as HH and SH, we found that the priorities of the management factors(contribution rates) were plant density(13.29%)>fertilizer(11.95%)>hybrids(8.19%)>irrigation(4%) for FP to HH, and hybrids(8.94%)>plant density(4.84%)>fertilizer(1.91%) for HH to SH. Therefore, increasing the planting density of FP was the key factor for decreasing the yield gap between FP and HH, while choosing hybrids with density and lodging tolerance was the key factor for decreasing the yield gap between HH and SH.
文摘Abiotic stresses like salinity and drought directly affect plant growth and water availability, resulting in lower yield in rice. So, a combination of stress tolerance along with enhanced grain yield is a major focus of rice breeding. It was reported earlier that loss in function of the drought and salt tolerance (DST) gene results in increase in grain production through downregulating Gn1a/OsCKX2 expression. Moreover, dst mutants also showed enhanced drought and salt tolerance in rice by regulating genes involved in ROS homeostasis. In the present study, we proceeded to test these reports by downregulating DST using artificial microRNA technology in the commercial but salt sensitive, high-yielding, BRRIdhan 28 (BR28). This cultivar was transformed with DST_artificial microRNA (DST_amiRNA) driven by the constitutive CaMV35S promoter using tissue culture independent Agrobacterium mediated in planta transformation. DST_amiRNA transgenic plants were confirmed by artificial microRNA specific PCR. Transformed plants at T0 generation showed vigorous growth with significantly longer panicle length and higher primary branching resulting in higher yield, compared to the wild type (WT) BR28. Semi-quantitative RT PCR confirmed the decrease in DST expression in the BR28 transgenic plants compared to WT. T1 transgenic plants also showed improvement in a number of physiological parameters and greater growth compared to WT after 14 days of 120 mM salt (NaCl) stress at seedling stage. Therefore, DST downregulated transgenic plants showed both higher stress tolerance as well as better yields. Furthermore, stable inheritance of the improved phenotype of the DST_amiRNA transgenics will be tested in advanced generations.
基金Supported by Guizhou Science&Technology Department Project([2006]2054)~~
文摘The aim was to research effects of meteorological factors on yield of ryegrass in fal ow field in winter. [Method] With grass yield as a dependent variable, effects of meteorological factors on ryegrass yield were explored by differ-ent planting methods. [Result] The yield of Zuanshi T was higher than that of Tegao; strip sowing performed better compared with dispersedly sowing and plough-ing better than no-til age; extremely high and low temperatures showed negative correlation with grass yield; higher daily average temperature, rainfal and sunshine hour improved grass yield; relative humidity and frost-free period had insignificant effects on yield. [Conclusion] The region with less extreme temperatures should be chosen as the site for growing ryegrass.
文摘There are numerous factors which can affect the lymph node(LN) yield in colon cancer specimens.The aim of this paper was to identify both modifiable and nonmodifiable factors that have been demonstrated toaffect colonic resection specimen LN yield and to summarise the pertinent literature on these topics.A literature review of Pub Med was performed to identify the potential factors which may influence the LN yield in colon cancer resection specimens.The terms used for the search were:LN,lymphadenectomy,LN yield,LN harvest,LN number,colon cancer and colorectal cancer.Both nonmodifiable and modifiable factors were identified.The review identified fifteen non-surgical factors:(13 nonmodifiable,2 modifiable) which may influence LN yield.LN yield is frequently reduced in older,obese patients and those with male sex and increased in patients with right sided,large,and poorly differentiated tumours.Patient ethnicity and lower socioeconomic class may negatively influence LN yield.Pre-operative tumour tattooing appears to increase LN yield.There are many factors that potentially influence the LN yield,although the strength of the association between the two varies greatly.Perfecting oncological resection and pathological analysis remain the cornerstones to achieving good quality and quantity LN yields in patients with colon cancer.
基金Under the auspices of Knowledge Innovation Programs of Chinese Academy of Sciences(No.KSCX1-YW-09-13)China Postdoctoral Science Foundation(No.07Z7601MZ1)
文摘Climate change is one of the most important challenges threatening agricultural grain yield and food security. Determining the factors influencing grain yield in Jilin Province and the weights of their contribution are a very important task, because Jilin Province is an important agriculture base in China. In this study, the accumulation factor sequence evaluating data method was used to analyze the climate and economic-technical factor contribution weights to grain yield and grain yield changes in each city of Jilin Province. Climate yield was also estimated to study the climate effect on the grain yield, and it was calculated in two ways： an improved algorithm and a traditional quadratic method. The results show that the climate and economicechnical factors have different contribution weights to grain yield in different cities in Jilin Province. The contribution weight of the climate factor to grain yield was 0.212-0.349, while that the economic-technical factor was 0.651-0.788. Furthermore, the changes of the climate factor contributing to grain yield changes accounted for 0.296-0.546, and the changes of the economic-technical factor accounted for 0.454-0.704. The weights of climate and economic-technical factor contributing to grain yield are very different between the eastern and western cities in Jilin Province, but their weights contributing to the grain yield change are similar in these cities. In general, the amount of fertilizer used per hectare （FUPH） is the main factor affecting grain yields and yield changes from 1980 to 2008. It is noted that when the FUPH growth rate stabilized after 1995, the effects of the climate factor on the grain yield become more obvious than before. The improved algorithm is effective for esti- mating climate yield in Jilin Province, and the climate yields were mostly between -500 kg/ha and 500 kg/ha, and showed a slightly rising trend in most cities.
基金Supported by National Key Technology Research and Development Program of the Ministry of Science and Technology of China(2015BAD07B04)Key Science and Technology Program of Henan Province,China(152102110059)
文摘Effects of environmental factors such as climate,topography,vegetation and soil in shelter forests in Three Gorges Reservoir Region on runoff and sediment yields were monitored to identify dominant environmental factors controlling runoff and sediment yields in 15 runoff plots in study area by soil sampling,laboratory analysis,stepwise regression analysis and path analysis,and to establish the main control environmental factors that affect runoff and sediment yields. The results showed that soil bulk density,herbaceous cover,slope,and canopy density were the significant factors controlling runoff,and the direct path coefficient of each factor was ranked as canopy closure(-0. 628) > litter thickness(-0. 547) > bulk density( 0. 509) > altitude( 0. 289). The indirect path coefficient was ranked as soil bulk density( 0. 354) >litter thickness(-0. 169) > altitude( 0. 126) > canopy closure(-0. 104). Therefore,canopy closure and litter thickness mainly had direct effects on runoff,while soil bulk density mainly had indirect effects through their contributions to other factors. Herbaceous cover,litter thickness,slope,canopy density,and altitude were the significant factors controlling sediment yields. The direct path coefficient of each factor was ranked as herbaceous cover(-0. 815) > litter thickness(-0. 777) > canopy closure(-0. 624) > slope( 0. 620). The indirect path coefficient was ranked as slope( 0. 272) > litter thickness(-0. 131) > canopy closure(-0. 097) > herbaceous cover(-0. 084). Therefore,herbaceous cover and litter thickness mainly had direct effects on sediment yields,while slope mainly had indirect effects through their contributions to other factors. All the selected environmental factors jointly explained 85. 5% and 78. 3% of runoff and sediment yield variability,respectively. However,there were large values of remaining path coefficients of other factors influencing runoff and sediment yields,which indicated that some important factors are not included and should be taken into account.
基金Supported by Special Funds for the System Construction of Modern Agricultural Industry Technology(CARS-18-37)~~
文摘The experiment was did in Liaocheng of west Shandong Province from^2009 to 2013 with ‘Lumianyan 28＇ which widely popularized and applied in production as test materials. The author discussed the influence of meteorological factors change on cotton yield characteristic in different years. The results were as follow：firstly, the accumulated temperature change was not significant in growth period, the coefficient of variation of sunshine hour was up to 7.4%, the coefficient of variation of precipitation was up to 18.4%; secondly, sunshine hour and, seed cotton yield,seed cotton yield before frost, lint yield were positively correlated; last, precipitation and seed cotton yield, seed cotton yield before frost, lint yield were negatively correlated, all reached significant level. It was showed that precipitation was the key meteorological conditions affecting cotton production.
基金National Key Research and Development Program of China(2017YFD0200808)Seed Science and Technology Major Special Program of Tianjin(18ZXZYNC00100)+1 种基金Scientific Research Program(Natural Science)of Tianjin Education Committee(2019KJ039)Graduate Research Innovation Program of Tianjin(2020YJSS128).
文摘In order to investigate the effects of meteorological factors on rape overwintering ability,forage yield and quality of rape in the North China plain,Brassia campestris L.and Brassica napus L.were used in this study.The results showed that compared with the B.napus L.varieties,the growth period of B.campestris L.was shortened by 10-15 d,the overwintering rate(WR)increased by 50.6%,and the density after winter(PD)increased by 41.5%.The fresh forage yield(FFY)and dry forage yield(DFY)of the B.campestris L.type significantly increased by 40.9%and 38.1%compared with the B.napus L.type.,respectively,while the forage quality of the B.napus L.type rape was significantly better than that of the B.campestris L.type.Compared with the B.campestris L.type,the crude protein(CP),fat,ash and total fatty acid(TFA)contents of the B.napus L.type of rape increased by 27.6%,42.9%,23.9%and 52.3%,respectively,and the milk productivity(HM),relative forage value(RFV)and relative forage quality(RFQ)increased by 14.0%,16.2%and 42.1%,respectively.The light and heat resources before wintering increased the WR and PD(P<0.05),and were positively correlated with FFY and DFY(P>0.05),and lower temperature during the wintering period led to lower WR(P<0.01).The light and heat resources during the overwintering period and after regreening were negatively correlated with FFY and DFY(P>0.05).The contents of CP,fat and TFA of rape had an extremely significant negative correlation with the temperature and sunshine hours before wintering,but an extremely significant positive correlation with the temperature during the wintering period and after regreening,as well as the sunshine hours and rainfall during the wintering period;and HM had an extremely significant positive correlation with the temperature,sunshine hours and rainfall during the wintering period,while RFV and RFQ were only extremely significantly positively correlated with the maximum temperature and rainfall.In summary,in the North China Plain,for autumn sowing rape,the B.campestris L.type can be selected to improve the wintering rate,and the B.napus L.type should be the main choice to improve the forage quality of rape.Therefore,the B.napus L.variety HYZ62 can be selected for autumn sowing in the North China Plain.
文摘Middle-season rice is an important food crop in southern rice areas of China,especially in Yunnan,the main rice-producing region.However,due to the impact of low temperature at the seedling stage and high or low temperature at the booting and heading stage of middle-season rice,the yield is not stable.Based on the data of yield factors of different middle-season rice varieties planted in the same ecological site in Jingdong County from 2009 to 2016,average development period was calculated using the data of development period measured in field during 2009-2016,and the average of meteorological factors(daily average temperature,daily maximum temperature,daily minimum temperature,and sunshine hours)and total precipitation were calculated.The correlation between meteorological factors in different development periods of each year and corresponding per unit area yield was analyzed.The results show that temperature is the most important factor affecting rice yield.Sufficient light is beneficial to the increase in the number of grains per spike and thousand seed weight at the sowing-seedling emergence stage and milk maturity-maturity stage.Excessive precipitation will reduce the number of grains per spike at the booting-heading stage.Excessive precipitation decreases the number of filled grains per spike at the jointing-booting stage,and proper drainage helps increase the formation rate of ears.This study provides scientific reference for rice production and management in this county in future.
