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Growth Dynamics and Optimal Harvesting Stage of Two Forage Maize Varieties
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作者 FU Feng-ling GUO Chang-jun TANG Qi-ling LIU Jian LI Wan-chen 《Agricultural Sciences in China》 CAS CSCD 2011年第2期220-227,共8页
SAUMZ 1 and SAUMZ 2 are two forage maize varieties reproduced by distant hybridization.In a randomized block experiment,their fresh forage yield and dry matter yield were investigated on the basis of growth period,lea... SAUMZ 1 and SAUMZ 2 are two forage maize varieties reproduced by distant hybridization.In a randomized block experiment,their fresh forage yield and dry matter yield were investigated on the basis of growth period,leaf stage,and effective accumulated temperature.The nutritional components were measured in a near infrared diffuse reflectance spectroscopy.Referring to the concept of forage grading index,a formula was constructed to calculate the total digestible energy.The investigated characters and indexes were adapted to suitable models of growth dynamics.The results showed that these two varieties have strong heterosis in fresh forage yield,dry matter yield,and total digestible energy.Their growth dynamics were adapted to Logistic models described by general equation y=k/(1+ae-bx).The forage grading indexes of these two varieties were decreased linearly along with the increasing of their leaf stage.The stopping point of fast growing period of total digestible energy estimated on the basis of leaf stage was suggested to be used as optimal harvesting stage of forage maize.The optimal harvesting stage was estimated to be tasseling stage for SAUMZ 1 and 19.50-leaf stage for SAUMZ 2. 展开更多
关键词 forage maize growth dynamics leaf stage optimal harvest stage total digestible energy
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Effects of Maize Silage Harvest Stage on Growth Performance and Economic Benefits of Beef Cattle
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作者 Shuo YANG Miaoyi ZHANG +7 位作者 Yancheng ZHOU Huihui LIU Yuping LIU Yuqi LIU Boyang LI Yi LI Mingjie YIN Xiaoliang PEI 《Agricultural Biotechnology》 CAS 2023年第2期48-50,共3页
[Objectives]This study aimed to investigate the effects of whole-crop maize silage harvested at different stages on growth and economic benefits of beef cattle.[Methods]A total of 30 Simmental crossbred cattle weighin... [Objectives]This study aimed to investigate the effects of whole-crop maize silage harvested at different stages on growth and economic benefits of beef cattle.[Methods]A total of 30 Simmental crossbred cattle weighing about 378 kg were randomly divided into three groups,respectively fed for 70 days with whole-crop maize silage harvested at milk stage(GroupⅠ),dough stage(GroupⅡ)and physiological maturity stage(GroupⅢ).Moreover,the cattle in all groups were given the same concentrate diet.[Results]There were significant differences in dry matter,crude protein and neutral detergent fiber between whole-crop maize silages harvested at different stages(P<0.05).The dry matter in GroupⅡandⅢwas significantly higher than that in GroupⅠ(P<0.05).The crude protein content peaked in GroupⅡ,up to 6.37%,which was significantly higher than that in GroupⅠ(by 12.74%,P<0.05)and GroupⅢ(by 9.26%,P<0.05).Starch content significantly increased with the postponing of maize harvest(P<0.05).The content of neutral detergent fiber in Group I was significantly higher than that in GroupⅡ(P<0.05)and GroupⅢ(P<0.05).The average daily weight gain in GroupⅡwas 8.53%higher than that in GroupⅠ(P<0.05)and 3.70%higher than that in GroupⅢ(P>0.05).The dry matter intake in GroupⅡwas significantly higher than that in GroupⅠ(P<0.05)and GroupⅢ(P<0.05).There was no significant difference in feed/gain ratio between the groups(P>0.05).The economic benefit in GroupⅡwas the highest,up to 9.99 yuan/day per capita.,followed by that in GroupⅢ,9.79 yuan/day per capita,and that in GroupⅠwas the lowest,only 8.03 yuan/day per capita.[Conclusions]The whole-crop maize silage harvested at dough stage has the best quality and produces the highest economic returns for beef cattle. 展开更多
关键词 Harvest stage Whole-crop maize silage Beef cattle Growth performance Economic benefits
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Optimum harvesting time of herbaceous peony buds for cutting flowers 被引量:2
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作者 YU Xiao-nan GUO Peng-peng LU Guang-pei ZHANG Qi-xiang 《Journal of Forestry Research》 SCIE CAS CSCD 2011年第1期137-140,共4页
The herbaceous peony is one of the cut flowers that has become increasingly popular in the international market in recent years. In the study, 11 cultivars of herbaceous peonies suitable for cutting flowers were selec... The herbaceous peony is one of the cut flowers that has become increasingly popular in the international market in recent years. In the study, 11 cultivars of herbaceous peonies suitable for cutting flowers were selected; different harvesting stages (three or four stages) were identified according to bud development observation (bud firmness, bud diameter, sepal angle, petal angle, and color showing). Moreover, flower development and vase life were also recorded in the experiment of vase. Bud development observation shows that there are great differences in optimum harvesting stage between the culti- vars, especially between the hybrid peony group and lactiflora group. This implies that bud diameter could not be the only indicator for optimum harvesting stage. Bud description, including sepal opening angle, sepal color, petal color showing, and degree of firmness, is necessary for the determination of the harvesting stage. Among the 11 cultivars,‘Pink Hawaiian Coral', ‘Red Charm', ‘Edulis Superba', ‘Red Magic', and ‘Sarah Bernhardt' should be harvested at stage 1. ‘Duchesse de Nemours', ‘Taff', ‘Sorbet' and ‘Monsieur Jules Elie' should be harvested at stage 2. ‘Kansas' should be at stage 3 and ‘Karl Rosenfield' at stage 4. The determination of optimum harvesting stage for each cultivar is an important element in cut flower production. 展开更多
关键词 herbaceous peony cut flower harvesting stage bud maturity
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EFFECTS OF HARVEST STAGE ON THE TOTAL LIPID AND FATTY ACID COMPOSITION OF FOUR CYLINDROTHECA STRAINS 被引量:4
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作者 梁英 麦康森 孙世春 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2002年第2期157-161,共5页
Four strains of Cylindrotheca (B156, B164, B196, and B200) were harvested at three phases in the growth curve and their total lipid and fatty acid composition were determined. Total lipid reached highest values in the... Four strains of Cylindrotheca (B156, B164, B196, and B200) were harvested at three phases in the growth curve and their total lipid and fatty acid composition were determined. Total lipid reached highest values in the late stationary phase in B156 (24.0%), B164 (26.6%) and B200 (17.3%), in the exponential phase in B196 (15.5%). Saturated fatty acids increased with the development of the culture in B156 and B196, and reached their highest values in the late stationary phase in B156 (41.7%) and B196 (45.1%), in the early stationary phase in B164 (45.4%) and B200 (37.6%). Monounsaturated fatty acids increased with the development of the culture in B196 and B200, and reached their highest values in the late stationary phase in B196 (32.4%) and B200 (32.8%), in the early stationary phase in B164 (31.0%) and in the exponential phase in B156 (29.3%). Polyunsaturated fatty acids decreased in the later phases of the culture in B164, B196 and B200, and peaked in the exponential phase in B164 (29.5%), B196 (42.9%) and B200 (37.3%), and in the early stationary phase in B156 (32.0%). 展开更多
关键词 Cylindrotheca harvest stage total lipid fatty acid
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OPTIMAL HARVESTING POLICY AND STABILITY FOR SINGLE-SPECIES GROWTH MODEL WITH STAGE STRUCTURE 被引量:10
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作者 SONGXinyu CHENLansun 《Journal of Systems Science & Complexity》 SCIE EI CSCD 2002年第2期194-201,共8页
Abstract. In this paper, we consider a stage structure population model with two lifestages, immature and mature, with harvesting mature population and stocking immaturepopulation. It is shown that under suitable hypo... Abstract. In this paper, we consider a stage structure population model with two lifestages, immature and mature, with harvesting mature population and stocking immaturepopulation. It is shown that under suitable hypotheses there exists a globally asymptoti-cally stable positive equilibrium. The effect of the delay on the populations at equilibriumand the optimal harvesting policy for mature population are also considered. 展开更多
关键词 Optimal harvesting policy stage structure equilibrium stability
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Effect of Maturity Indices on Growth and Quality of High Value Vegetables
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作者 A. K. M. Quamruzzaman Ferdouse Islam +1 位作者 Limu Akter Sharmilla Rani Mallick 《American Journal of Plant Sciences》 CAS 2022年第7期1042-1062,共21页
The study took place at Bangladesh Agricultural Research Institute’s Olericulture Division’s research farm from March 2021 to February 2022 (BARI). In a protected net house, we investigated the impact of five differ... The study took place at Bangladesh Agricultural Research Institute’s Olericulture Division’s research farm from March 2021 to February 2022 (BARI). In a protected net house, we investigated the impact of five different types of vegetables on various maturation stages, including tomato, broccoli, sweet pepper, cucumber, and netted melon. Vegetables cultivated under protected conditions in a transparent poly-film net house can improve quality, maturity, fruit size, and yield. When fruits and vegetables are picked before they are fully mature, they may stay green for longer, but they may not ripen to a satisfactory color and flavor, resulting in a loss of consumer confidence. Furthermore, because fruit continues to grow until the harvest, immature fruit will be smaller than mature fruit, reducing harvest yield. We tried to determine the right maturation stages in order to avoid product loss during our investigation. The tomato was found to be an appropriate size (6.5 cm length and 6.2 cm diameter), weight (84 g), TSS (4.5 percent), pH (4.3), “turning red”, and “tasty” at the week 5 stage, while the broccoli was found to be an appropriate size (12.0 cm length and 13.0 cm diameter), weight (360 g), and “green” color at the week 5 stage. At the week 6 stage, the nettled melon was found to be of appropriate size (15.2 cm length and 14.5 cm diameter), weight (800 g), TSS (10.8 percent), pH (6.3), “net fully developed” on the fruit skin and “much tasty,” while cucumber was found to be of appropriate size (8.8 - 10.8 cm length and 2.2 - 2.9 cm diameter), weight (61 - 88 g), TSS (3.8 - 4.1 percent), pH (6.3), “less powdery”. As a result, establishing the optimal maturity of our research will benefit both consumers and growers. 展开更多
关键词 Maturity Indices GROWTH QUALITY High Value Vegetables TSS pH Different Harvest stages
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THE OPTIMAL HARVESTING OF A PREDATOR-PREY SYSTEM WITH STAGE-STRUCTURE
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作者 Li Qiuying Zhang Fengqin Jia Jianwen 《Annals of Differential Equations》 2007年第4期440-445,共6页
In this paper, we establish the exploitation of continuous harvest of predator and prey with stage-structures. We investigate the properties of harvesting multispecies systems. With some special methods, we obtain bou... In this paper, we establish the exploitation of continuous harvest of predator and prey with stage-structures. We investigate the properties of harvesting multispecies systems. With some special methods, we obtain boundedness and global attractiveness of all the nonnegative equilibria for proportional harvest. Finally, we solve the problem of optimal harvest policy using Pontragin's maximal principle. 展开更多
关键词 stage structure predator-prey harvesting time-delay
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