渭北旱塬红富士苹果需水量与限水灌溉效应研究

Study on Water Requirement and Limited Irrigation Effects of Dwarfing Red Fuji Apple Tree on Weibei of Loess Plateau

应用田测法 ,对渭北旱塬南部高原台塬过渡区 ,矮化红富士苹果需水量、需水规律及限水灌溉效应进行了研究。结果表明 ,该区矮化红富士苹果生育期总需水量为 494.8～ 5 5 2 .7m m ,其中干旱年份高于湿润年份 ;年生育期内以 6月最大 ,7～ 8月次之 ,10月最小。果实膨大和花芽分化盛期需水量最大 ,占总需水量的 41.4%～ 46 .7% ,新梢生长与果实发育前期次之 ,占总需水量的 34 .0 %～ 34 .2 % ;并得出了该区矮化红富士苹果生育期的作物系数KC值。对不同降水年型土壤水分盈亏状况与该区降水特点分析表明 ,该区 5 0 %年份降水能够满足矮化红富士苹果生长需要 ,无需灌水 ;10 %年份降水基本满足需要 ,生育期末土壤贮水基本持平 ,但由于受降雨分配影响 ,需水关键期仍需适量补充灌水 ;40 %年份降水明显不足 ,必须灌水才能维持稳产、高产。干旱年份补充灌水对当年和第二年树体生长。

Based on field experiment, the water requirement and limited irrigation effects of dwarfing red Fuji apple tree was studied. The results showed that total water requirement of the tree in south part of Weibei is from 494.8 mm to 552.7 mm throughout the growing season; and is higher in the dry year than in the normal year. During growth period, monthly water requirement is the highest in the June as well as July and August, and it is the lowest in the October. The water requirement of fruit swelling and the peak of flower bud differentiation phase account for 41.4%～46.7% of the total water requirement; that of new shoot growth and young fruits development phase make up 34.0%～34.2% of the total.Besides,the Kc value is given for calculating the tree's water requirement in similar regions. By means of principle of water equilibrium analysis indicated that there are 50% foliated season in which precipitation can meet the tree's water needs, 10% foliated season in which soil water storage level off, but the fruit tree need irrigation in the critical period, and 40% foliated season in which soil water severe deficiency, the fruit tree must be irrigated to gain high and stable yield. Limited irrigation in dry year can promote the tree's growth, fruit development and yield in the year as well as the next year.