In order to control the spawning quality and improve the economic benefit of Apostichopus japonicus Selenka, the indoor temperature and light control methods were employed for artificial maturation, spawning and hatch...In order to control the spawning quality and improve the economic benefit of Apostichopus japonicus Selenka, the indoor temperature and light control methods were employed for artificial maturation, spawning and hatching of A. japonicus, and the larval survival rate, disease incidence rate and economic benefit were analyzed. The results showed that compared with those of conventional temperature-reared larvae, the survival rate of raised temperature-reared larvae was increased by 15.8%, the disease incidence rate was reduced by 10.2%, and the economic benefit was improved by 21.6%. These results will provide theoretical basis and technical support for the artificial breeding of A. japonicus.展开更多
A study was conducted to evaluate the effects of sludge （industrial and residential） on seed germination and growth performance of Acacia auriculiformis seedlings at the nursery of Institute of Forestry and Environm...A study was conducted to evaluate the effects of sludge （industrial and residential） on seed germination and growth performance of Acacia auriculiformis seedlings at the nursery of Institute of Forestry and Environmental Sciences, Chittagong University （IFESCU）, Bangladesh. Before sowing of the seeds, different combinations of sludge were incorporated with the nutrient-deficient natural forest soils. Seed germination and growth parameters of the seedlings （shoot and root length, collar diameter, fresh and dry weight of shoot, and root and total dry biomass） were recorded after one, two and three months of seed sowing. Physio-chemical parameters （pH, organic carbon, nitrogen, phosphorus, and potassium） and heavy metals （chromium, nickel, manganese, cadmium and zinc） of each treatment were also analyzed before sowing of seeds and after harvesting of seedlings. Results show that the seed germination percentage and the seedling growth parameters varied significantly in the soil added with sludge in comparison to control. The highest germination percentage （90%） was observed in the treatment of soil with residential sludge of 2：1 compared to control. The highest growth and biomass of the seedlings as well as the maximum percentage of organic carbon and nutrients （N, P and K） were also recorded in the same combination. Soil added with industrial sludge had a higher concentration of heavy metal than that of residential sludge. The highest concentrations of heavy metals were found in soil added with industrial sludge of 1：1. It is recommended that soil added with residential sludge of 2：1 provide good condition for better seed germination and growth ofA. auriculiformis seedlings in degraded forest soil.展开更多
The investigation was conducted to know the effect of 2, 4-Dichlorophenoxy acetic acid and inoculation on Para-nodule formation and growth parameters in wheat. Formation of nodular outgrowth on the roots of wheat seed...The investigation was conducted to know the effect of 2, 4-Dichlorophenoxy acetic acid and inoculation on Para-nodule formation and growth parameters in wheat. Formation of nodular outgrowth on the roots of wheat seedlings treated with 2, 4-D commenced in 8-10 days. The maximum Para-nodule formation was found in 1 ppm of 2, 4-D when incubated with bradyrhizobium P-132. Inoculation of the same has helped to increase the number of Para-nodule, but not essential for Para-nodulation. Histological study shows that, these induced Para-nodules originated from the pericycle and these are appeared to be modified lateral roots and Para-nodule structure formations however, it enhanced by bradyrhizobial inoculation.展开更多
A large portion of irrigation farmers make use of subjective （intuition） irrigation scheduling methods as supposed to objective or scientific irrigation scheduling methods, which need to be changed. The BEsproeiings...A large portion of irrigation farmers make use of subjective （intuition） irrigation scheduling methods as supposed to objective or scientific irrigation scheduling methods, which need to be changed. The BEsproeiingsWAterbestuursprogram （BEWAB＋） irrigation scheduling programme is based on the water balance equation and needs： （1） a crop production function; （2） a relative consumptive water demand curve and （3） an allowable depletion subroutine. The objective of this paper was to describe research aimed at obtaining information on （1） and （2） for pea and also to describe the effect of water application on yield and water use of pea. BEWAB＋ uses this information to estimate the daily irrigation water requirements for a particular soil-crop-atmosphere system under irrigation. A field experiment, based on published line-source irrigation methodology, was conducted on a 3 m deep loamy fine sand Bainsvlei or Ustic Quartzipsamment soil near Bloemfontein （26°08′S; 29°01′E） in South Africa. Results showed that there is a linear relationship of the form Ys = 8.07ET - 249 （r2 = 0.91）, where Ys is the seed yield of pea （kg/ha） and ET is evapotranspiration for the growing season （mm）. The relative consumptive water demand curve is represented by the following third order polynomial function that describes the relationship between time and relative ET for a pea growing season of 120 days： ETrelx = 0.09419646 - 0.01302413x ＋ 0.00059008x2 - 0.00000371x3. ETrelz denotes relative ET and x denotes time in days. A workable balance between practical problem solving and advanced irrigation science has been established with BEWAB＋. Pre-plant irrigation schedules can be made for semi-arid areas with the BEWAB＋ programme using easily obtainable inputs, like target yield, soil depth and soil particle size distribution information.展开更多
文摘In order to control the spawning quality and improve the economic benefit of Apostichopus japonicus Selenka, the indoor temperature and light control methods were employed for artificial maturation, spawning and hatching of A. japonicus, and the larval survival rate, disease incidence rate and economic benefit were analyzed. The results showed that compared with those of conventional temperature-reared larvae, the survival rate of raised temperature-reared larvae was increased by 15.8%, the disease incidence rate was reduced by 10.2%, and the economic benefit was improved by 21.6%. These results will provide theoretical basis and technical support for the artificial breeding of A. japonicus.
文摘A study was conducted to evaluate the effects of sludge （industrial and residential） on seed germination and growth performance of Acacia auriculiformis seedlings at the nursery of Institute of Forestry and Environmental Sciences, Chittagong University （IFESCU）, Bangladesh. Before sowing of the seeds, different combinations of sludge were incorporated with the nutrient-deficient natural forest soils. Seed germination and growth parameters of the seedlings （shoot and root length, collar diameter, fresh and dry weight of shoot, and root and total dry biomass） were recorded after one, two and three months of seed sowing. Physio-chemical parameters （pH, organic carbon, nitrogen, phosphorus, and potassium） and heavy metals （chromium, nickel, manganese, cadmium and zinc） of each treatment were also analyzed before sowing of seeds and after harvesting of seedlings. Results show that the seed germination percentage and the seedling growth parameters varied significantly in the soil added with sludge in comparison to control. The highest germination percentage （90%） was observed in the treatment of soil with residential sludge of 2：1 compared to control. The highest growth and biomass of the seedlings as well as the maximum percentage of organic carbon and nutrients （N, P and K） were also recorded in the same combination. Soil added with industrial sludge had a higher concentration of heavy metal than that of residential sludge. The highest concentrations of heavy metals were found in soil added with industrial sludge of 1：1. It is recommended that soil added with residential sludge of 2：1 provide good condition for better seed germination and growth ofA. auriculiformis seedlings in degraded forest soil.
文摘The investigation was conducted to know the effect of 2, 4-Dichlorophenoxy acetic acid and inoculation on Para-nodule formation and growth parameters in wheat. Formation of nodular outgrowth on the roots of wheat seedlings treated with 2, 4-D commenced in 8-10 days. The maximum Para-nodule formation was found in 1 ppm of 2, 4-D when incubated with bradyrhizobium P-132. Inoculation of the same has helped to increase the number of Para-nodule, but not essential for Para-nodulation. Histological study shows that, these induced Para-nodules originated from the pericycle and these are appeared to be modified lateral roots and Para-nodule structure formations however, it enhanced by bradyrhizobial inoculation.
文摘A large portion of irrigation farmers make use of subjective （intuition） irrigation scheduling methods as supposed to objective or scientific irrigation scheduling methods, which need to be changed. The BEsproeiingsWAterbestuursprogram （BEWAB＋） irrigation scheduling programme is based on the water balance equation and needs： （1） a crop production function; （2） a relative consumptive water demand curve and （3） an allowable depletion subroutine. The objective of this paper was to describe research aimed at obtaining information on （1） and （2） for pea and also to describe the effect of water application on yield and water use of pea. BEWAB＋ uses this information to estimate the daily irrigation water requirements for a particular soil-crop-atmosphere system under irrigation. A field experiment, based on published line-source irrigation methodology, was conducted on a 3 m deep loamy fine sand Bainsvlei or Ustic Quartzipsamment soil near Bloemfontein （26°08′S; 29°01′E） in South Africa. Results showed that there is a linear relationship of the form Ys = 8.07ET - 249 （r2 = 0.91）, where Ys is the seed yield of pea （kg/ha） and ET is evapotranspiration for the growing season （mm）. The relative consumptive water demand curve is represented by the following third order polynomial function that describes the relationship between time and relative ET for a pea growing season of 120 days： ETrelx = 0.09419646 - 0.01302413x ＋ 0.00059008x2 - 0.00000371x3. ETrelz denotes relative ET and x denotes time in days. A workable balance between practical problem solving and advanced irrigation science has been established with BEWAB＋. Pre-plant irrigation schedules can be made for semi-arid areas with the BEWAB＋ programme using easily obtainable inputs, like target yield, soil depth and soil particle size distribution information.
