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
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...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 fl uorescence parameters(Fo, Fm, 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 mg · L-1 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 fl uorescence parameters, our fi ndings 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
The plant-made seedling-growing tray cultivation technique is an effective way to improve maize yield and quality in China’s cold northern area.However,the corn seedling nursery carrier and tray cultivation technique...The plant-made seedling-growing tray cultivation technique is an effective way to improve maize yield and quality in China’s cold northern area.However,the corn seedling nursery carrier and tray cultivation technique has been proved poor in adaptability.After comparing several nursery carriers,a design for a plant-made seedling-growing tray that is suitable for maize transplantation was proposed in which rice straw was used as the primary raw material.The preparation method,processing and structural dimensions of the tray were investigated and designed,five types of plant-made seedling-growing trays with different formulations were proposed.The shear mechanical properties and the shear strength of the plant-made seedling-growing trays were tested to determine the shear force needed for cutting through trays prepared with increasing mass ratios of rice straw and the effect of the shearing rate on the shear strength.The results showed that at a shearing rate of 100 mm/min,the maximum shear force decreased gradually as the mass ratio of straw was increased and that the hardness of the tray decreased as its shear strength decreased.Under three shearing rates(100 mm/min,200 mm/min and 500 mm/min)and a blade displacement of 10 mm,the shear force was the highest at the point at which the tray was cut through;the required shear force to cut through the tray then gradually decreased.Trays with the same straw composition showed no significant influence of shearing rate on the tray’s shear strength at shearing rates of 100 mm/min,200 mm/min or 500 mm/min.This study describes a multi-tray,single-strip nursery carrier for use in plant-made seedling-growing tray cultivation and proposes a theoretical basis for the design of a rotary transplanting device,the key part of a maize plant-made seedling-growing tray transplanter.展开更多
De-etiolation consists of a series of developmental and physiological changes that a plant undergoes in response to light.During this process light,an important environmental signal,triggers the inhibition of mesocoty...De-etiolation consists of a series of developmental and physiological changes that a plant undergoes in response to light.During this process light,an important environmental signal,triggers the inhibition of mesocotyl elongation and the production of photosynthetically active chloroplasts,and etiolated leaves transition from the"sink"stage to the"source"stage.De-etiolation has been extensively studied in maize(Zea mays L.).However,little is known about how this transition is regulated.In this study,we described a quantitative proteomic and phosphoproteomic atlas of the de-etiolation process in maize.We identified 16,420 proteins in proteome,among which 14,168 proteins were quantified.In addition,8746 phosphorylation sites within 3110 proteins were identified.From the combined proteomic and phosphoproteomic data,we identified a total of 17,436 proteins.Only 7.0%(998/14,168)of proteins significantly changed in abundance during de-etiolation.In contrast,26.6%of phosphorylated proteins exhibited significant changes in phosphorylation level;these included proteins involved in gene expression and homeostatic pathways and rate-limiting enzymes involved in photosynthetic light and carbon reactions.Based on phosphoproteomic analysis,34.0%(1057/3110)of phosphorylated proteins identified in this study contained more than 2 phosphorylation sites,and 37 proteins contained more than 16 phosphorylation sites,indicating that multi-phosphorylation is ubiquitous during the de-etiolation process.Our results suggest that plants might preferentially regulate the level of posttranslational modifications(PTMs)rather than protein abundance for adapting to changing environments.The study of PTMs could thus better reveal the regulation of de-etiolation.展开更多
Accurate crop detection is the prerequisite for the operation of intelligent agricultural machinery.Image recognition usually lacks accurate orientation information,and Lidar point clouds are not easy to distinguish d...Accurate crop detection is the prerequisite for the operation of intelligent agricultural machinery.Image recognition usually lacks accurate orientation information,and Lidar point clouds are not easy to distinguish different objects.Fortunately,the fusion of images and Lidar points can complement each other.This research aimed to detect maize(Zea mays L.)seedlings by fusing Lidar data with images.By applying coordinate transformation and time stamps,the images and Lidar points were realized homogeneous in spatial as well as temporal dimensions.Deep learning was used to develop a maize seedling recognition model,then the model recognized maize seedlings by labeling them with bounding boxes.Meanwhile,Lidar points were mapped to the bounding boxes.Only one-third of points that fell into the right middle of bounding boxes were selected for clustering operation,the calculated center of the cluster provided spatial information for target maize seedlings.This study modified the classical single shot multi-box detector(SSD)by merely linking the last feature map to the final output layer,owing to the higher feature maps having the unique advantages of detecting relatively larger objects.In images,maize seedlings were just the largest objects owing to be shot on purpose.This modification enabled the recognition model to finish recognizing an image by only consuming around 60 ms,which saved about 10 ms/image compared with the classical SSD model.The experiment was conducted in a maize field,and the maize was during the elongation stage.Experimental results demonstrated that the standard deviations for maximum distance error and maximum angle error were 1.4 cm and 1.1°,respectively,which can be tolerated under current technical requirements.Since agricultural fields are subject to staple crop-orientated and changeable ambient environment,the fusion of images and Lidar points can derive more precision information,and make agricultural machinery smarter.This study can act as an upstream technology for other researches on intelligent agricultural machinery.展开更多
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 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 fl uorescence parameters(Fo, Fm, 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 mg · L-1 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 fl uorescence parameters, our fi ndings 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the financially support from the Education Department Heilongjiang Province(No.2014TD010)project of the Heilongjiang Provincial Land Reclamation Bureau(No.HNK125B-07-17)Project of the Education Department Heilongjiang Province(No.12531450)。
文摘The plant-made seedling-growing tray cultivation technique is an effective way to improve maize yield and quality in China’s cold northern area.However,the corn seedling nursery carrier and tray cultivation technique has been proved poor in adaptability.After comparing several nursery carriers,a design for a plant-made seedling-growing tray that is suitable for maize transplantation was proposed in which rice straw was used as the primary raw material.The preparation method,processing and structural dimensions of the tray were investigated and designed,five types of plant-made seedling-growing trays with different formulations were proposed.The shear mechanical properties and the shear strength of the plant-made seedling-growing trays were tested to determine the shear force needed for cutting through trays prepared with increasing mass ratios of rice straw and the effect of the shearing rate on the shear strength.The results showed that at a shearing rate of 100 mm/min,the maximum shear force decreased gradually as the mass ratio of straw was increased and that the hardness of the tray decreased as its shear strength decreased.Under three shearing rates(100 mm/min,200 mm/min and 500 mm/min)and a blade displacement of 10 mm,the shear force was the highest at the point at which the tray was cut through;the required shear force to cut through the tray then gradually decreased.Trays with the same straw composition showed no significant influence of shearing rate on the tray’s shear strength at shearing rates of 100 mm/min,200 mm/min or 500 mm/min.This study describes a multi-tray,single-strip nursery carrier for use in plant-made seedling-growing tray cultivation and proposes a theoretical basis for the design of a rotary transplanting device,the key part of a maize plant-made seedling-growing tray transplanter.
基金supported by the National Key R&D Program of China(Grant No.2016YFD0101003)the Heilongjiang Provincial Outstanding Youth Science Foundation,China(Grant No.JC2017008)
文摘De-etiolation consists of a series of developmental and physiological changes that a plant undergoes in response to light.During this process light,an important environmental signal,triggers the inhibition of mesocotyl elongation and the production of photosynthetically active chloroplasts,and etiolated leaves transition from the"sink"stage to the"source"stage.De-etiolation has been extensively studied in maize(Zea mays L.).However,little is known about how this transition is regulated.In this study,we described a quantitative proteomic and phosphoproteomic atlas of the de-etiolation process in maize.We identified 16,420 proteins in proteome,among which 14,168 proteins were quantified.In addition,8746 phosphorylation sites within 3110 proteins were identified.From the combined proteomic and phosphoproteomic data,we identified a total of 17,436 proteins.Only 7.0%(998/14,168)of proteins significantly changed in abundance during de-etiolation.In contrast,26.6%of phosphorylated proteins exhibited significant changes in phosphorylation level;these included proteins involved in gene expression and homeostatic pathways and rate-limiting enzymes involved in photosynthetic light and carbon reactions.Based on phosphoproteomic analysis,34.0%(1057/3110)of phosphorylated proteins identified in this study contained more than 2 phosphorylation sites,and 37 proteins contained more than 16 phosphorylation sites,indicating that multi-phosphorylation is ubiquitous during the de-etiolation process.Our results suggest that plants might preferentially regulate the level of posttranslational modifications(PTMs)rather than protein abundance for adapting to changing environments.The study of PTMs could thus better reveal the regulation of de-etiolation.
基金financially supported by the National Natural Science Foundation of China(Grant No.31901408)the Science and Technology Development Plan of Jilin Province(Grant No.20200201206JC).
文摘Accurate crop detection is the prerequisite for the operation of intelligent agricultural machinery.Image recognition usually lacks accurate orientation information,and Lidar point clouds are not easy to distinguish different objects.Fortunately,the fusion of images and Lidar points can complement each other.This research aimed to detect maize(Zea mays L.)seedlings by fusing Lidar data with images.By applying coordinate transformation and time stamps,the images and Lidar points were realized homogeneous in spatial as well as temporal dimensions.Deep learning was used to develop a maize seedling recognition model,then the model recognized maize seedlings by labeling them with bounding boxes.Meanwhile,Lidar points were mapped to the bounding boxes.Only one-third of points that fell into the right middle of bounding boxes were selected for clustering operation,the calculated center of the cluster provided spatial information for target maize seedlings.This study modified the classical single shot multi-box detector(SSD)by merely linking the last feature map to the final output layer,owing to the higher feature maps having the unique advantages of detecting relatively larger objects.In images,maize seedlings were just the largest objects owing to be shot on purpose.This modification enabled the recognition model to finish recognizing an image by only consuming around 60 ms,which saved about 10 ms/image compared with the classical SSD model.The experiment was conducted in a maize field,and the maize was during the elongation stage.Experimental results demonstrated that the standard deviations for maximum distance error and maximum angle error were 1.4 cm and 1.1°,respectively,which can be tolerated under current technical requirements.Since agricultural fields are subject to staple crop-orientated and changeable ambient environment,the fusion of images and Lidar points can derive more precision information,and make agricultural machinery smarter.This study can act as an upstream technology for other researches on intelligent agricultural machinery.
