大豆通过框栽试验,证明 NK 营养作底肥或追肥施用,生育期中植株体内NK 营养积累量高峰期为鼓粒期。氮积累量随钾营养的增加而增强,呈显著直线回归关系。所以,在大豆鼓粒期之前,应在施磷肥的基础上,再配合施用氮钾肥作底肥或花期追肥施用...大豆通过框栽试验,证明 NK 营养作底肥或追肥施用,生育期中植株体内NK 营养积累量高峰期为鼓粒期。氮积累量随钾营养的增加而增强,呈显著直线回归关系。所以,在大豆鼓粒期之前,应在施磷肥的基础上,再配合施用氮钾肥作底肥或花期追肥施用,方能促其营养生长和生殖生长,使植株增高,荚数增多,体内干物质积累量增加,从而提高大豆的产量并改善了品质。较对照增产17%～30%,比施磷肥增产10%～17%,蛋白质提高22%～26%,脂肪提高25%～41%.展开更多
An 8 weeks feeding experiment was conducted to determine the effect of dietary potassium on the growth and physio-logical acclimation of Pacific white shrimp （Litopenaeus vannamei） reared in diluted seawater （salin...An 8 weeks feeding experiment was conducted to determine the effect of dietary potassium on the growth and physio-logical acclimation of Pacific white shrimp （Litopenaeus vannamei） reared in diluted seawater （salinity 4）. Six semi-purified practical diets containing 0.59, 0.96, 1.26, 1.48, 1.74, and 2.17 g potassium K＋ per 100 g diet were formulated, respectively. The survival and feed conversion rate did not show significant difference among groups of shrimps given these diets （P〉0.05）. The shrimps fed the diets containing 0.96-1.48 g K＋ per 100g diet gained the highest weight, specific growth rate, and protein efficiency ratio. Their ammonium-N excretion rate as well as hemolymph concentration of Na＋ and C1- were significantly lower than those of the control （P〈0.05）, but a reverse trend was observed for their gill Na＋/K＋-ATPase. Moreover, the shrimps fed with 1.48 g K＋ per 100 g diet were the highest in hemolymph urea level, and the phenoloxidase and lysozyme activities were significantly higher than those of the control （P〈0.05）. The growth and physiological response of the test shrimps suggested that diet containing 1.48 g K＋ per 100 g diet improved the growth of L. vannamei in low-salinity seawater, and enhanced the physiological acclimation of the organism.展开更多
文摘大豆通过框栽试验,证明 NK 营养作底肥或追肥施用,生育期中植株体内NK 营养积累量高峰期为鼓粒期。氮积累量随钾营养的增加而增强,呈显著直线回归关系。所以,在大豆鼓粒期之前,应在施磷肥的基础上,再配合施用氮钾肥作底肥或花期追肥施用,方能促其营养生长和生殖生长,使植株增高,荚数增多,体内干物质积累量增加,从而提高大豆的产量并改善了品质。较对照增产17%～30%,比施磷肥增产10%～17%,蛋白质提高22%～26%,脂肪提高25%～41%.
文摘An 8 weeks feeding experiment was conducted to determine the effect of dietary potassium on the growth and physio-logical acclimation of Pacific white shrimp （Litopenaeus vannamei） reared in diluted seawater （salinity 4）. Six semi-purified practical diets containing 0.59, 0.96, 1.26, 1.48, 1.74, and 2.17 g potassium K＋ per 100 g diet were formulated, respectively. The survival and feed conversion rate did not show significant difference among groups of shrimps given these diets （P〉0.05）. The shrimps fed the diets containing 0.96-1.48 g K＋ per 100g diet gained the highest weight, specific growth rate, and protein efficiency ratio. Their ammonium-N excretion rate as well as hemolymph concentration of Na＋ and C1- were significantly lower than those of the control （P〈0.05）, but a reverse trend was observed for their gill Na＋/K＋-ATPase. Moreover, the shrimps fed with 1.48 g K＋ per 100 g diet were the highest in hemolymph urea level, and the phenoloxidase and lysozyme activities were significantly higher than those of the control （P〈0.05）. The growth and physiological response of the test shrimps suggested that diet containing 1.48 g K＋ per 100 g diet improved the growth of L. vannamei in low-salinity seawater, and enhanced the physiological acclimation of the organism.
