Due to the global expansion of irrigated areas and the limited availability of irrigation water, it is necessary to optimize water use in order to maximize crop yields under water deficit conditions. To evaluate the y...Due to the global expansion of irrigated areas and the limited availability of irrigation water, it is necessary to optimize water use in order to maximize crop yields under water deficit conditions. To evaluate the yield response of two processing tomato hybrids (Ercole and Genius) grown under different irrigation treatments, a field trial was conducted during the 2008 growing season in Southern Italy. Three irrigation treatments were used: the restitution of 70% of maximum evapotranspiration (ETc) both under "Deficit Irrigation" (70DI) and "Partial Root-zone Drying" (70PRD) strategies; full irrigated (FI: 100% ETc). The two water deficit irrigation treatments (DI and PRD) showed stomatal conductance values lower than FI treatment and saved a substantial amount of water maintaining reasonable marketable yield. Moreover, PRD strategy showed slightly higher "Water Use Efficiency" (WUE) values than DI. Finally, "yield response factor" (Ky) showed always values less than unity, indicating the possibility to adopt, within certain limited condition, both DI and PRD in field-grown processing tomato cultivated in Southern Italy. In conclusion, in our experimental conditions, deficit irrigation practices seem to be acceptable relatively to processing tomato yield aspects and Ky could be promoted as a useful indicator for irrigation in water deficit conditions.展开更多
An industrialized technique of preparation for oxidized com starch using oxygen as oxidant was investigated in this paper. The industrialized preparation parameters were optimized as follows: reaction temperature 85-...An industrialized technique of preparation for oxidized com starch using oxygen as oxidant was investigated in this paper. The industrialized preparation parameters were optimized as follows: reaction temperature 85-95 ℃, oxygen flow rate 8-12 L/min, reaction time 210 min, the ratio of starch to water 1:5, 3.5 wt% of NaOH and 0.1 wt% of catalyst. The experimental results show that the concentration of hydrolysate-oxidaton product is 16-18 wt%. The powdered products were gained through dehydrated and powdered process using quadruple-effect evaporator, spray drying tower and guide shell mixer. The composting test indicates that the degradability of the oxidized corn starch can reach 76.4%. The complexation capacity of calcium ions reaches 108.5 mg per gram oxidized starch, and the detergency ratio (P) reaches 1.30 as builder.展开更多
Knowledge of plant responses to soil water availability is essential for the development of effcient irrigation strategies.However,notably different results have been obtained in the past on the responses of various p...Knowledge of plant responses to soil water availability is essential for the development of effcient irrigation strategies.However,notably different results have been obtained in the past on the responses of various physiological indices for different plants to soil water availability.In this study,the responses of various plant processes to soil water availability were compared with data from pot and field plot experiments conducted on maize(Zea mays L.).Consistent results were obtained between pot and field plot experiments for the responses of various relative plant indices to changes in the fraction of available soil water(FASW).A threshold value,where the relative plant indices began to decrease with soil drying,and a lower water limit,where the decline of relative plant indices changed to a very slow rate,were found.Evaporative demand not only influenced the transpiration rate over a daily scale but also determined the difference in transpirational response to soil water availability among the transient,daily and seasonal time scales.At the seasonal scale,cumulative transpiration decreased linearly with soil drying,but the decrease of transpiration from FASW = 1 in response to water deficits did not affect dry weight until FASW = 0.75.On the other hand,the decrease in dry weight was comparable with plant height and leaf area.Therefore,the plant responses to soil water availability were notably different among various plant indices of maize and were influenced by the weather conditions.展开更多
文摘Due to the global expansion of irrigated areas and the limited availability of irrigation water, it is necessary to optimize water use in order to maximize crop yields under water deficit conditions. To evaluate the yield response of two processing tomato hybrids (Ercole and Genius) grown under different irrigation treatments, a field trial was conducted during the 2008 growing season in Southern Italy. Three irrigation treatments were used: the restitution of 70% of maximum evapotranspiration (ETc) both under "Deficit Irrigation" (70DI) and "Partial Root-zone Drying" (70PRD) strategies; full irrigated (FI: 100% ETc). The two water deficit irrigation treatments (DI and PRD) showed stomatal conductance values lower than FI treatment and saved a substantial amount of water maintaining reasonable marketable yield. Moreover, PRD strategy showed slightly higher "Water Use Efficiency" (WUE) values than DI. Finally, "yield response factor" (Ky) showed always values less than unity, indicating the possibility to adopt, within certain limited condition, both DI and PRD in field-grown processing tomato cultivated in Southern Italy. In conclusion, in our experimental conditions, deficit irrigation practices seem to be acceptable relatively to processing tomato yield aspects and Ky could be promoted as a useful indicator for irrigation in water deficit conditions.
文摘An industrialized technique of preparation for oxidized com starch using oxygen as oxidant was investigated in this paper. The industrialized preparation parameters were optimized as follows: reaction temperature 85-95 ℃, oxygen flow rate 8-12 L/min, reaction time 210 min, the ratio of starch to water 1:5, 3.5 wt% of NaOH and 0.1 wt% of catalyst. The experimental results show that the concentration of hydrolysate-oxidaton product is 16-18 wt%. The powdered products were gained through dehydrated and powdered process using quadruple-effect evaporator, spray drying tower and guide shell mixer. The composting test indicates that the degradability of the oxidized corn starch can reach 76.4%. The complexation capacity of calcium ions reaches 108.5 mg per gram oxidized starch, and the detergency ratio (P) reaches 1.30 as builder.
基金Supported by the CAS/SAFEA International Partnership Program for Creative Research Teamsthe Knowledge Innovation Program of the Chinese Academy of Sciences (No.KSCX1-YW-09-07)the National Natural Science Foundationof China (No.40671083)
文摘Knowledge of plant responses to soil water availability is essential for the development of effcient irrigation strategies.However,notably different results have been obtained in the past on the responses of various physiological indices for different plants to soil water availability.In this study,the responses of various plant processes to soil water availability were compared with data from pot and field plot experiments conducted on maize(Zea mays L.).Consistent results were obtained between pot and field plot experiments for the responses of various relative plant indices to changes in the fraction of available soil water(FASW).A threshold value,where the relative plant indices began to decrease with soil drying,and a lower water limit,where the decline of relative plant indices changed to a very slow rate,were found.Evaporative demand not only influenced the transpiration rate over a daily scale but also determined the difference in transpirational response to soil water availability among the transient,daily and seasonal time scales.At the seasonal scale,cumulative transpiration decreased linearly with soil drying,but the decrease of transpiration from FASW = 1 in response to water deficits did not affect dry weight until FASW = 0.75.On the other hand,the decrease in dry weight was comparable with plant height and leaf area.Therefore,the plant responses to soil water availability were notably different among various plant indices of maize and were influenced by the weather conditions.